6 neurot prezentari

8/17/2019 6 NeuroT prezentari

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CONSTRUCTIA SIASAMBLAREASENSORILOR ELECTROCHIMI

PENTRU DETECTIANEUROTRANSMITATORILOR


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CatecholaminesCatecholamines originate from a wide range of neural pathways by employingbiogenic amines as neurotransmitters (Stoica et al., 2004).The neurotransmitter metabolites released into the cerebrospinal fluid can be a

sensiti e indicator of neuronal functioning in nearby diencephalon structures(!ightman et al., "#$$).

Therefore, it is of great clinical importance to measure neurotransmitters and theirmetabolites le el in the e%tracelluar fluid in order to monitor neurotransmissio

process (&eters et al., 2000).'opamine (' ) is an important neurotransmitter because it in ol ed in motor andcogniti e functionsdeficits in brain may cause &ar*inson+s disease in humanbeings. ' has also been associated with the reward system, the circuitry inthe brain is responsible for the moti ation to see* out stimuli as well as theemotions for feeling satisfied and satiated in one+s en ironment ( inton and!ightman, 200-).

rom the iew of point of physiological importance, it is a challenge to monitor 'and its metabolite of -,4/dihydro%yphenylacetic acid (' & C), because 'le el control is ital in the treatment of &ar*inson+s disease.

Stoica, 1., 1indgren/S 3lander, ., u5gas, T., 6orton, 1., 2004. 7iosensor based on cellobiose dehydrogenase for detection ofcatecholamines. nal. Chem. 89, 49#0:49#9.

!ightman, .;., ;ay, 1.1., ;ichael, .C., "#$$. 'etection of dopamine dynamics in the brain. nal. Chem. 90, 89# :88# .

&eters, ., ;ichael, .C., 2000. ?uantitati e aspects of brain microdialysis. nal. Chim. cta 4"2, ":"2.inton, 7.


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Beurotransmitters


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Beurotransmitters


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Catecholamines


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Catecholamines


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;etabolism of 1/' &

COMT

COMT

AAD

MAOAD

MAOAD

COMT

COMT = Catechol O-methyl transferase

AAD = Aromatic L-aminoacid decarboxylase

MAO = MonoamineOxidase

AD = Aldehydedehydrogenase

NE = NorepinephrineNESelegiline

Carbidopa

Entacapone


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Biological Sensor - Dopamine

' is electrochemically acti e : the de elopment of an electrochemical methodthat is capable of sensing ' is important.

lectrochemcial detection suffers from interference (from scorbic cid ( )and Dric cid (D ). Typical concentrations of is "0/4 to "0/- mol dm/- while '("0/8 to "0/Amol dm/-).


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IL REPREZINTA PROIECTAREA SI REALIZAREA UNOR ELECTROZIcare sa permita detectia simultana a mai multor neurotransmitatori

eliminindu-se totdata si efectele interferentilor posibili e!" acidul ascorbic#

O repre$inta constructia unor sensori amperometrici en$imatici

SCOPULReali$area si %alidarea unor instrumente analitice care sa poata determina in timp real

neurotransmitatorii

O&IECTI'UL (ENERAL

O POSI&ILA CALE )E ATIN(ERE A ACESTUI SCOP


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the Neurotransmitter sensors based on the SWCNT Wmodi!ied mi"roe#e"trodes$

to%ards the neurotransmitter biosensors usin& the Lutamate o'idase en()me but startin& !rom the mode#en()me *usin& !or +O' the u"ose biosensor assemb#),$

"on"#usions and -ers-e"ti.es/


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n the planned !or"n the planned !or"

".". The applicability of CBT modified surfaces withThe applicability of CBT modified surfaces withselected en5ymes (e.g. glucose o%idase orselected en5ymes (e.g. glucose o%idase orcellobise dehydrogenase) andEorcellobise dehydrogenase) andEor

electrocatalists (li*e metallo phtalocyanines)electrocatalists (li*e metallo phtalocyanines)will be in estigated and used for de elopingwill be in estigated and used for de elopingdifferent *ind of microbiosensors fordifferent *ind of microbiosensors forneurotransmitters detectionneurotransmitters detection

2.2. The stability and morphological characteristicsThe stability and morphological characteristicsof these modified surfaces will be studied byof these modified surfaces will be studied bydifferent surface analytical methods.different surface analytical methods.


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S& CT ' STD'F T

G &roiectarea si reali5area unor microbiosensorielectrochimici ba5ati pe BTC pentru e aluareaneurotransmitatorilor

G laborarea unei metodologii adce ate de lucru cumicrobiosensorii pentru detectia neurotransmitatorilor inprobe reale

G alidarea datelor obtinute prin utili5area metodelor clasice(standard)


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ariatii ale concentratiilor de catecolamine@ariatii ale concentratiilor de catecolamine@serotoninserotonin aa ##

norepinenorepine f f rinrin aasisi dopamindopamin aaconduc la instalarea unor boli neuropsihiceconduc la instalarea unor boli neuropsihice

Concentratii mari deConcentratii mari decatecolaminecatecolamine : conduc la : conduc la manie ..Concentratii mici de catecolamine conduc laConcentratii mici de catecolamine conduc ladepresidepresi ee

Catecolaminele fac parte din clasa NE$%OT%AN&M TATO% LO%fiind sinteti5ate la ni elul sistemului ner os central

O*

O* O*

O*

O*

O*

+-

+- +

-

)OPA,INA NOREPINE RINA EPINE RINA

N* .

/ N* .

*O / N*

0

/*O

&tr'ct'rile chimice ale catecolaminelor


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Beurotransmitatorii sunt molecule chimice care e%ista pe o perioadamica de timp in fluidul e%tra/celular, ele fiin eliberate in mediu in spatiulsinaptic pe perioada transmiterii unui mesa neurochimic

eali5area unei sinapse intre 2 celule ner oase (neuroni)


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Beurotransmitatorii sunt molecule chimice care e%ista pe o perioadamica de timp in fluidul e%tra/celular, ele fiind eliberate in mediu inspatiul sinaptic pe perioada transmiterii unui mesa neurochimic

eali5area unei sinapse intre 2 celule ner oase (neuroni)


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CATECOLAM NELE s'nt & NTET (ATE la ni elul sistemului ner os central in cadrul unei

sec ente de reactii catali5ate en5imatic

Cooper 1R2 &loom E2 and Rot3 R* 4554# )opamine2 in The Biochemical Basis of Pharmacology 2 pp 0678..92 O!ford Uni%ersit: Press2 Ne;


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7rain 'isorders

Beurotransmitters, ddiction and

'epression


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7urden of disease in urope

Original data) *ro+ected ,ears Li ed !ith Disability .,LD/ by selected disorders for the E$ .Olesen 0 Leonardi# 1223/


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The Need7rain disorders e.g. :'epression : n%iety :&ain : pilepsy :Schi5ophrenia :'ementias : ddiction

ccount for about4AL5 of all theburden of disease in urope andgrowing

6rain disorders and their ne'rotransmitter targets

&chi7ophrenia 8 DopamineG eleased by stimulant drugs Hcocaine,amphetamineI :;ore dopamine Jmore pleasureJaddiction (dependenta) :!here in brainKGncreased release in schi7ophrenia G%ed'ced in*ar"inson9s disease :can be restored by brain implantsG;ay be red'ced in depression

Depression - &erotonine ntidepressants designed to increase A>T/but we still do not *now". if A>Tis lo! in depression2. if antidepressants increase this- and if so whereK;icrobiosensors could be a solution toanswer these and other importantLuestions by using them for Luantitati edetermination of neurotransmitters


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Dregarile ale sistem'l'i ner os sine'rotransmitatorii implicati

GDepresia) serotonine (A>T), noradrenalineGAnxietatea ) :A6A# noradrenaline, A>T

G*ain) endorphins, noradrenalineGEpilepsy) 6 7 , glutamateG&chi7ophrenia) dopamina, A>T, noradrenalineGDementia; cetylcholine, glutamateGAddiction) 6 7 , glutamate, endorphins

Dopamina - schi7ofrenieG liberata de droguridrugs stimulatorii(cocaina, amfetamina) :;ai multa dopamina Jmai multa

placereJ dependenta :Dnde in creerKGCresterea secretiei / inschi7ophrenieGScaderea secretiei / in*ar"insonG&oate fi redusa indepresie

&erotonina / depresie ntidepressants designed to increase A>T/but we still do not *now". if A>T is low in depression2. if antidepressants increase this- and if so whereK;icrobiosensors could be a solution toanswer these and other importantLuestions by using them for Luantitati edetermination of neurotransmitters


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PROBLEME legate de DETECTIAneurotransmitatorilor @

in sit'

1imitari (constringeri) temporale si spatiale impuse de insasi mediul de determinare

Timpul de e%istenta a neurotransmitatorilor in fluidul e%tracelular este limitat (citesute de milisecunde

proba de anali5at se afla intr/un olum e%trem de mic (tpic citi a picolitrii)

in fl'id'l extra-cel'lar

cesta este un mediu e%trem de comple%@toate moleculele care intra si ies dintr/o celula trebie sa treaca prin acest spatiu(e%. metaboliti, hormoni, neurotransmitatori)

;atrice ostilaContine surfactanti (e%. lipide), proteins, electrocatali5atori (e%. glutation si ascorbat)


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care pre5inta caracteristicile legate de

sensibilitate,

selecti itate,dimensiune a probei

si mai important re5olutie temporala

si care conduce la reali5area unor masuratori rele ante ale dinamiciineurotransmitatorilor in i o

&roblema interferentele datorate acidului ascorbic in raspunsul oltametric

R" ," >i?3tman et" al"2 Nature 0@0 459@# 4 7"

Fn literatura de specialitate sunt descrise un numar relati restrins de tehnici care permonitori5area in i o a neurotransmitatoriolr

oltametria ciclica cu baleere rapida ba5ata pe microelectro5i


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ELECTRO OREZA CAPILARA

SI

CRO,ATO(RA IA )E LIC*I)ECU

)ETECTIE ELECTROC*I,ICA

METODE ANAL T CE

folosite pentru determinarea neurotransmitatorilor


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SCOPUL

)e$%oltatrea si %alidarea sensorilor bio#c3imici pentru determinarea in timp real aneurotransmitatorilor

%ista un interes ma or in reali5area electro5ilor pentru determinareaelectrochimica a neurotransmitatorilor@ dopamina, norepinefrina,

acetilcolina si serotonina (A/>T).

Neurotransmitatori pot f oxidatiusor si deci,

Au ost realizate o serie de TEHNICI ELECTROCHIMICE pentrudetectia lor a ind la !aza di erite materiale de electrod


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microelectro$i de Pt2 AuCarbon sticlos modificatPasta de carbon,icrofibre de carbon

Nanotuburi de carbon

LISTA MATERIALELOR DE ELECTROD

OLOSITE IN )ETECTIA NEUROTRANS,ITATORILOR in vivo si in vitro selecti%#

F. Valentini, S.Orlanducci, E.Tamburri, M.Terranova, A. Curulli, G. Palleschi, ElectroanF. Valentini, S.Orlanducci, E.Tamburri, M.Terranova, A. Curulli, G. Palleschi, Electroan


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Fn domeniul medical, monitori5area, neurotransmitatorilor la pacientiidepresi i repre5inta o necesitate stringenta care generea5a informatii

legate de starea de sanatate a pacientilor depresi i, aceasta a indimplicatii sociale si economice ma ore.

Fn ultimii ani, in literatura de specialitate au fostreali5ati si caracteri5ati un numar mare debiosensori pentru detectia neurotransmitatorilor.

lectro5ii pe ba5a de nanotuburi de carbonbeneficia5a de o serie de a anta e (e%. dimensiunireduse, etc) si de aceea sunt utili5ati in reali5areamicrobiosensorilor.

Com(atibilitate lor cu tehnolo)ia de micro*abricatie (recum si (retul lCom(atibilitate lor cu tehnolo)ia de micro*abricatie (recum si (retul lacesti electro+i sa re(re+inte un instrument analitic (romitator (entruacesti electro+i sa re(re+inte un instrument analitic (romitator (entruneurotransmitatorilor neurotransmitatorilor in vivoin vivo -.-.


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FOLOSIREA MEDIATORILOR REDOX a imbunatatit semnificati !e"f#"mantele

de dctectie a neurotransmitatorilor este ba$ata pe folosirea

O CALE POSIBILA

Substrate Product

Substrate Produc

Substrate Product

O 2 H2 O 2 Med ox Med red

electrod

"trate#ia actuala in domeniu este aceea de a proiecta electrozi care p a mai multor neurotransmitatori, eliminandu$se e ectul inter erent al

biosensorilor electrochimici

electro5ilor chimic modificati ba5ati pe en5ime


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Structura ?enerala a ,eP3C

A" Ciucu2 R" P" &ald;in2 Electroanl:sis2 $ 4550# 747A" Ciucu2 C" Ne?ulescu2 R" P" &ald;in2 &iosens" &ioelectron"2 46 0BB.# 05.

Complecsii de metalici ai ftalocianinelor ,eP3C# sunt binecunoscutii ca fiind electrocatali$atori pentrumulte reactii

Fn acest sens s/a in estigat posibilitatea utili5arii ftalocianinelor pentru detectia neurotransmita

Proprietatile cele mai importante ale ,eP3Cs2 sunt

solubilitate mica in maDoritatea sol%entilor

Pre$inta un domeniu lar? de potentiale care se modifica odata cu

sc3imbarea metalului central

&otentiale de o%idare s. SC Ni II# P3C /4"B7 '

e II# P3C /B"4@ 'Co II# P3C / B"99 ')eri%ati de studiat

2 F2 FF2 FFF-tetraamino P3C 2 F2 FF2 FFF-tetra=is-0-aminofeno!i P3C


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SE%SORII am!e"#met"ici Beneficia&a de # se"ie de a anta'e pret de cost sca$ut us#" de fab"icat in #"ice f#"mat si dimensiune

Care impreuna fac posibila t3at ma=es possibla fabricarea la un pret sca$ut a unor

O(id#"educta&ele sunt elemente binecunoscute de recunoastere moleculara

6 O&EN&O% ELECT%OC4 M C

DETECT A NE$%OT%AN&M TATO% LO% 6A(ATA *E


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DETECT A NE$%OT%AN&M TATO% LO% 6A(ATA *EELECT%O( C4 M C MOD 5 CAT 6A(AT *E EN( ME

6o% este o en5ima ideal de folosit in constructia biosensorilor 6o% este o en5ima ideal de folosit in constructia biosensorilor datorita@datorita@

Specificitatii fata de gluco5aSpecificitatii fata de gluco5aCapacitatii catalitice mariCapacitatii catalitice mari

StabilitatiiStabilitatii

Dn biosensor pentru gluco5a ba5at pe un electrod modificat cu 6o% si pe cuplul redo% ?E>? poate fi folositpentru detectia compusilor dihidro%i fenolici (hidrochinona, dopamina, epinefrina, norepinefrina etc.)

;ecanismul de acMiune al gluco/o%ida5ei


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Di)*d"#(*!)en#ls a"e c#nsumed at t)e elect"#de su"face+ but "egene"ated b* ,#( in !"esence #fgluc#se -)ic) gene"ate a signal am!lificati#n .

7ioelectrocatalytic reaction of glucose o%idation at the surface

of an amperometric carbon paste electrode modified with 6o%.

This 6o% based sensory system is applicable for detection of dihydro%yphenols(>?, catechol, dopamine,epinephrine and norepinephrine) with increased sensiti itydue to the response amplification.

" ,i$utani2 et" al"" &iosens" &ioelectron"2 @ 4554# .B7 . Ciucu, C. &Ntroescu, nal. 1ett.,>? , ("#$4) "4"8

A" Ciucu2 '" ,a?earu2 C" Luca2 Anal" Lett"2 ./+ 4567# 055

/ Another strategy is to 'se the clasical gl'cose biosensor


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&ioelectrocatal:tic reaction of ?lucose o!idation at t3e surface of anamperometric carbon paste electrode modified ;it3 (o! .

Di)*d"#(*!)en#ls a"e c#nsumed at t)e elect"#desu"face+ but "egene"ated b* ,#( in !"esence #f gluc#se

-)ic) gene"ate a signal am!lificati#n .

. ;i5utani, et. al.. 7iosens. 7ioelectron., 9 ("##") -0A . Ciucu, C. &Ntroescu, nal. 1ett.,>? , ("#$4) "4"8

. Ciucu, . ;agearu, C. 1uca, nal. 1ett.,>@# ("#$A) 2##

. / Another strategy is to se the clasical gl cose biosensor

6o% is ideally suited for use in biosensor6o% is ideally suited for use in biosensordesign due to its@design due to its@

high specificity for glucosehigh specificity for glucosehigh turno er ratehigh turno er rate

high stabilityhigh stability

glucose sensor could be prepared by using an electrode coatedwith a layer containing immobili5ed 6o% and ?E>? redo% couple.

T3is (o! based sensor: s:stem is used for detection of di3:dro!:p3enols*G2 catec3ol2 dopamine2epinep3rine and norepinep3rine#

;it3 increased sensiti%it: due to t3e response amplification"


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. III0 O !#sibila alte"nati a in c#nst"ucttia bi#sens#"il#" !ent"u detectianeu"#t"ansmitat#"il#" este utili&a"ea cel#bi#& de)id"#gena&ei 1 C%H& # en&ima

cu c#fact#"i micsti

CDH a fost descoperita de 'lla (estermar) si *arl$Eri) Eri)sson in Stoc holm

C%H este produsa extracelular de un#i precum+ Phanerochaete chrysosporium

"tructura C%H+ este o /avoen+ima care

contineun co*actor /avinic,si un al 001lea co*actor de hem

2. A. Gre)) and A 3eller, Anal. Chem. , - " 44$& #%'1#56.


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;ecanismul bioelectrocatalitic de functionare al biosensorului pe ba5a de C'>

Transferul direct sus# si mediat Dos# de electronidintre C)* si suprafata unui electrod de ?rafite

T" Larsson2 et al"2 Anal" C3im" Acta ..4 455@# 0B9"A" Lind?ren2 L" Stoica2 T" Ru$?as2 A" Ciucu + L" (orton2 T3e Anal:st2 .2$ 2 4555#709-7.0"C" Nistor2 1 Emneus2 L" (orton2 A" Ciucu2 Anal" C3im" Acta2 3/4+ 4555# .B5-.0@"

'ite$a de transfer de electroni intramolecular estemica

Solutie folosirea unui mediator in scopul cresteriiite5ei de transfer de electroni dintre en5im

electrod

olosindu/se aceasta schema de detectie s/a detectat dopamina limita de detectie fiind

1 B nM

&ELECT E %E&*ON&E O5 DO*AM NE N T4E *%E&ENCE


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&ELECT E %E& ON&E O5 DO AM NE N T4E %E&ENCEO5 A&CO%6 C AC D AT CA%6ON NANOT$6E& *A&TE MOD 5 ED ELECT%ODE

A Ci'c'#A Ci'c'# A Cioban'A Cioban'Dni ersity of 7ucharest, aculty of Chemistry, omania,

ODni ersity of ;edicine and &harmacy Carol 'a ila, 7ucharest, omania

There is considerable interest in de eloping electrodes for electrochemicaldetermination of neurotransmitters such as dopamine (' ) and serotonin (A/>T). 1ole els of ' ha e been found in patients with &ar*inson+s disease. Serotonin A/>T

widely distributed in the brain, and together with other neurotransmitters, plays aimportant role in brain functions. 7oth ' and A/>T are readily o%idi5ed hence

electrochemical techniLues ha e been e%plored for their analysis H"/4I ascorbic ( ) represent a ma or interferent in the determination.

NT%OD$CT ON

Selecti e electrochemical detection of ' and A/>T in thepresence of at multi/wall carbon nanotube paste electrodemodified with cobalt(FF) phthalocyanine (;!CBT/Co&C).

7< CTF


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Metallophthalocyanines .M*hc/ complexes are coordinationcompo'nds !here a transition metal is coordinated !ith a

phthalocyanine ring

5ig're > The structure of metallophthalocyanines MPhc

acts as electrocatalysts for many reactions H4,"2:"4I,the electrochemical properties of ;&hc can be modulated by@

changing the central metal atom or introducing substituents in the phthalocyanine ring,

ery low solubility in nearly all sol ents, both aLueous and orga

&roperties@

The 'se of M*hc complexes as electrocatalysts for the determination ofne'rotransmitters has not recei ed m'ch attention .

Fn this wor*, oltammetric electrodes based on ;&hc compounds (5ig >) ha e been used as the wor*ing electrode in

cyclic oltammetry e%periments, for e aluating neurotransmitters.

The oltammetric sensors ha e shown an additional interest due to their@high sensiti ity,

ersatilityand simplicity,

with a choice of potential range, wa eform and electrode material.


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ELECT%ODE& $&ED 5O% T4E DETECT ON O5ELECT%ODE& $&ED 5O% T4E DETECT ON O5

NE$%OT%AN&M TTE%& 5%OM T &&$E# N O AND N T%ONE$%OT%AN&M TTE%& 5%OM T &&$E# N O AND N T%O

G modified glassy carbon electrodes (6C ),G carbon nanotube electrodes,G carbon/based ring dis* electrodes,G carbon paste electrodes (C& ),G &t microelectrodes,G carbon micro fiber electrodes,G single wall carbon nanotubes

The strategy now is to design electrodes that can allow for simultaneous detection of se eral neurotransmitters, while eliminating the interfering effects of ascorbic a

A**%OAC4E& 5O% T4E DETE%M NAT ON O5 NE$%OT%AN&M TTE%&)

capillary electrophoresis with electrochemical detectionliLuid chromatography with electrochemical detection

fast/scan cyclic oltammetry ( SC ) using microelectrodes (for in i o studie

T> '


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; T> 'lectrochemical approachG Cyclic oltammetryG 'iferential pulse oltammetry

< E . P ;!CBT&/Co&C

A$ E P &t

%E5 E P gQ gCl (-;)

%es'lts

Cyclic voltammograms for a 10 mM K !"e#C$%& ' solution at a unmo(ifie(M)C$TP electro(e # * % an( at a M)C$TP-CoPC electro(e # ---- %.

Con(itions+ 1,0 M K$ , v /0 m sec


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Electrocatalytic mechanism)

n the basis of these obser ations, it would appear that the most reasonable mechanism for thedopamine o%idation is then a catalytic C seLuence@

Co(FFF)&C R ' Co(FF)&hc R ' o%idation productCo(FF)&C / e/ Co(FFF)&C

similar mechanism would be e%pected for A/>T.

Fnterference of ascorbic acid in the ;!CBT& modified electrodes response

a obser ed at R 0."2 s gE gCl

Ascorbic acid ,# )opamine ,# I p2a µ A

4"B ! 4B-@ 7"0 ! 4B -@ .@"B

4"B ! 4B-@ 0"4B ! 4B-@ .."B

4"B ! 4B-@ 4"4 ! 4B -@ .B"

4"B ! 4B-@ 7"0 ! 4B -@ .0".

4"B ! 4B-@ 0"B ! 4B-@ 05"9

mean .0".


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Concl'sionlectrochemical approach is used to detect dopamine at low

applied potential.The present study proposes an easy/to/ma*e and low/cost

sensor construction for the selecti e determination ofdopamine.

The chemically/modified multi walled carbon nanotube pasteelectrode is capable of enhanced electrochemical monitoringof dopamine due to the properties of the electrode material

and metalo/phthalocyanines used as mediators.Fnterference of ascorbic acid in the multi walled carbon

nanotube paste modified electrodes response was eliminated.


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.. aa za .za . iolo#icaiolo#ica aa

%%epresepres ieiiei


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7olile mentale repre5inta o arie enorma si comple%a de cercetare in care se simtene oia de5 oltarii unor noi directii de abordare a problematicii din acest domeniu

6olile mentale dist'rbagandirea, afecti itatea, starea psihica si capacitatea de integrare a persoanelorsuferind de aceste maladii.


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Depresia

este o boala a mintii si corpului

are cea mai mare incidenta in lume afectand milioane de oameni

depresia apare de doua ori mai frec ent la femei decat la barbati, dinmoti e care nu sunt total intelese

netratata, depresia conduce la suicid

ata de sinucidere in tarile est europene este de 4 pana la 9 ori maimare comparati cu cea din SD .


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/%epresia este cancerul

emotiilor/ 0Le1is (olpert&


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'epression is diagnosed on thebasis of a patient s beha iour, not

on the basis of laboratory test.


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Depresia) Dimensi'nea*roblemei

G A / "2 of men and "0 / 20 of women in the D.S. willsuffer from ama or depressi e episode at some time intheir life.

G "A of depressi es commit suicide each yearG Fn "##9 the Centers for 'isease Control and &re ention

listeds'icide as the ninth leading ca'se of death inthe $ & (slightly behind infection with the F'S irus),

ta*ing the li es of -0.$92 peopleG Fn "##2 the estimatedcosts of depression totalled U4-billion, mostly from reduced or lost wor*er producti ity.

(Source+ $emeroff, 1223 )


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'epresia'epresie primarN

unipolarNbipolarN

mi%tN

'epresie secundarNboalN &ar*inson

depresia din schi5ofreniedepresia din bolile cardio asculareafecMiuni neurologice degenerati e


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Dnipolar depressi e disorders

Dnipolar depressi e disorders arecharacteri5ed by depressi e symptomsonly, without any history of a manic,mi%ed or hypomanic episode.

This criterion distinguishes them from thegroup of bipolar (affecti e) disorders.


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Criteria of ma or depressi e disorder A O er the last 1 !ee"s# B of the follo!ing

feat'res sho'ld be present most of the day#or nearly e ery day .m'st incl'de > or 1/ )

G". depressed mood

G2. loss of interest or pleasure in almost allacti itiesG-. significant weight loss or gain (more than

A change in " month) or increase ordecrease in appetite nearly e ery dayG4. insomnia or hypersomniaGA. psychomotor agitation or retardation


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G9. fatigue or loss of energyG8. feelings of worthlessness or

e%cessi e or inappropriate guiltG$. diminished ability to thin* or

concentrate, or indecisi enessG#. recurrent thoughts of death , or

recurrent suicidal ideation, or asuicide attempt, or a specific plan forcommitting suicide.


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G6 The symptoms ca'se clinically significantdistress or impairment in social# occ'pational#

or other important areas of f'nctioningGC The symptoms are not d'e to a

physicalForganic factor or illness .e g # a dr'gab'se# a medication# a general medicalcondition/

GD The symptoms are not better explained byberea ement .altho'gh this can becomplicated by ma+or depression/

4th 5evision of the 6merican Psychiatric 6ssociation7s Diagnostic an(Statistics Manual #6merican Psychiatric 6ssociation 1224%

& FBCF& 1FF B D T BS;FVWT


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&tare psihica# emotii#f'nctia cogniti a

Moti atie

Apetitsex'al

Agresi itate

Anxietateritabilitate

Energienteres

mp'lsi itate

Motilitate

Norepinefrina &erotonina

Dopamina

& FBCF& 1FF B D T BS;FVWTF;&1FC VF FB TD17D ' & SF

& M &tahlEssential Psychopharmacology, in Neuroscientific Basis and Practical Applications 1nd ed Cambridge# $G# Cambridge $ni ersity *ress# 1222# p >B1

; FB B D T BS;FTT S F;&1F ' FB


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Mood# emotion#cogniti e f'nction

Moti ation

&exAppetite

Aggression

Anxietyrritability

Energynterest

mp'lsi ity

Dri e

Norepinephrine &erotonin

Dopamine

; FB B D T BS;FTT S F;&1F FB' & SF B TD17D

& M &tahlEssential Psychopharmacology, in Neuroscientific Basis and Practical Applications 1nd ed Cambridge# $G# Cambridge $ni ersity *ress# 1222# p >B1


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Th l t h f


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There are se eral reasons to search forbiological mar*ers for depression.

'epression is diagnosed on the basis of apatient s beha iour, not on the basis oflaboratory test.

The biological mar*ers for depression couldbe used for @G a better diagnostic toolG to track improvement under drug treatment

G to better understand the biological basis of depressionG to develop more effective drug treatments

H i h th i f


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H;onoamine hypothesis ofdepressionX

Ghas been the theory e%plaining biologicalbasis of depression (Stahl, "##$).

G This theory states that depression isessentially due to adeficiency in one ofthree catecholamines ) serotonin#norepinephrine# or dopamine ( notablynorepinephrine / B and serotonin Ahydro%ytryptamine / A>T ).

&ermissi e 7iogenic mine


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&ermissi e 7iogenic mineTheory

GFf catecholamine acti ity isincreased then thepatient will e%hibitmania .

GFf catecholamine acti ity isdecreased then thepatient will e%hibitdepression .

GConseLuently depression could be treated byeither treating the underlying serotoninabnormality, or by restoring B acti ity tonormal.


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B metabolism and depression

". depression is associated with afunctional deficiency of noradrenalin(B ) and Y -/4 ;>&6 (specially inurine )

2. mania is associated with an e%cess of Band -/4 ;>&6.

(Schild*rant


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G;>&6 (-/metho%y/4/hydro%y/phenyl/

glycol) is produced when B isbro*en down by en5ymes.G;>&6 (-/metho%y

4hydro%yphenylglycol) is the principaB metabolite found in the humancerebrospinal fluid (CS ) which

suggests that it may pro ide a goodestimate of B acti ity.


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'epresia Zi serotonina (A/>T)


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epresia Zi serotonina (A/>T)G 'eficitul transmisiei serotoninergice este anomalia de

neurotransmisie cel mai frec ent implicatN [n etiopatogeniadepresiei ( sberg Zi an &raag : "#$4)@

GnumNr crescut de receptori A/>T2 [n corte%ul frontal lasinucigaZi (Stanley / "##0)

GcurbN A/>F mult scN5utN la sinucigaZi ( sberg / "#$4)GcurbN scN5utN de A/>F [n 1C la cei cu tentati e de

suicid iolent (Cocarro / "#$#)G alori scN5ute ale triptofanului liber la depresi i.

)in punct de %edere clinic2 depresia cu deficit de serotoninH se)in punct de %edere clinic2 depresia cu deficit de serotoninH secaracteri$ea$H princaracteri$ea$H prin

pre$en a an!ietH ii pre$en a an!ietH iicomportament de tip ostilcomportament de tip ostilrisc suicidar crescutrisc suicidar crescut

l * il d i i d li b[ d


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aluarea mar*erilor de tip indolic sub[mparte depresprin deficit de serotoninN [n douN categorii

Gcu ni el scN5ut de indoli : potenMial suicidar ridicat ( reland : "#$A), pentru care

acti itatea ; plachetarN este un mar*er biologic controlat

genetic, ni elele scN5ute ale acti itNMii ; plachetare suntcorelate cu hiperacti itatea ; neuronalN Zi deficienMaserotoninicN.

Gcu ni el normal sau crescut al indolilor : sugerea5N o altN subformN biochimicN de depresie Zi riscul

instalNrii sindromului serotoninergic [n situaMia utili5Nrii medantidepresi e de tip inhibitori de recaptare a serotoninei

A/>T metabolism and depression


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A/>T metabolism and depression

&erotonin .B-4T/# and a possibleinteraction bet!een B-4T andNAdrenaline# may play an importantrole in mood# s'ch as interactionbet!een B-4T and hypothalam's

pit'itary adrenal system


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G Studies suggest that le els of serotonin .B4T/and serotonin metabolites . B4 AA 8 Bhydroxy -

indole acetic acid / are red'ced in brain tiss'eand the le els of serotonin metabolites aredecreased in cerebrospinal fl'id (CS ) ofdepressed patients.

G&atients with low CS A>F tend to be thepatients with impulsi e beha iors, such as suicide.G1ow le els A/>F may be a biological mar*er for

s'icidal beha io'r eference@ 6s8erg # Science , 121, 493- 430, 129&%


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' i Zi d i


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'epresia Zi dopamina'in punct de edere clinic, depresia prin deficit de

dopaminN se caracteri5ea5N prin@GinhibiMie psihomotorieGtensiune intrapsihicN marcatN

GtendinMe abuliceGrisc suicidar ;ar*eri biochimici@

GprolactinaGacidul homo anilmandelic (> )

: ni ele scN5ute : depresie inhibatN cu risc suicidar crescut : ni ele crescute : tendinMN la depresie delirantN sau ira

dispo5iMional.

' metabolism and depression


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metabolism and depression

GClinical data has clearly shown acorrelation between dopamine deficiencyand depression.

G The strongest e idence implicatingdopaminergic in ol ement in depressionhas come from studies of thedopaminemetabolite# homo anillic acid .4 A/ incerebrospinal fl'id


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GDepressed patients !ho had attempteds'icide had significantly lo!er 'rinaryconcentrations of 4 A and lo!er total bodyconcentrations of dopamine than patients!ith depression !ho did not attempt

s'icide .6o!den et al >II?/

'epresia Zi noradrenalina


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epresia Zi noradrenalina

7unney / "#9A considerN deficitul noradrenergic ni el limbic ca mecanismul de ba5N [n depresi

'in punct de edere clinic, deficitul denoradrenalinN determinN o formN particularN depresiei, caracteri5atN prin@

GinhibiMie psihomotorieGtendinMe apato/abuliceGpseudo/deficit cogniti


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Tot noradrenalina

B t b li d d i


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B metabolism and depression

". depression is associated with afunctional deficiency of noradrenalin(B ) and Y -/4 ;>&6 (specially inurine )

2. mania is associated with an e%cess of Band -/4 ;>&6.

(Schild*rant


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G;>&6 (-/metho%y/4/hydro%y/phenyl/glycol) is produced when B isbro*en down by en5ymes.

G;>&6 (-/metho%y

4hydro%yphenylglycol) is the principaB metabolite found in the humancerebrospinal fluid (CS ) which

suggests that it may pro ide a goodestimate of B acti ity.

alorile indicatorilor biochimici ai deficitului B


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alorile indicatorilor biochimici ai deficitului BG;>&6 (;etilhidro%ifenilglicol) plasmatic sau

urinar G alori normale indicN depresie cu acti itatepredominent serotoninergicN sau dopaminergicN.

Gni elul crescut constituie un argument pentru ipote5ahipercolinergicN a depresiei (1eong / "#$8)

G alori scN5ute indicN depresie prin deficit B .

G' & 6 ('ihidro%ifeniletilenglicol) plasmaticGmar*er fidel al metabolismului B , la depresi i

' & 6 a \nd un ni el scN5ut (1oo / "#$-, Scatton /"#$9).

Fndicatorii en5imatici ai depresiei B


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Fndicatorii en5imatici ai depresiei B

GscNderea acti itNMii dopaminbetahidro%ila('7>) nu are aloare de mar*er la depresi iibipolari ( isemman / "#$-, ihmer / "#$#),la unipolari atribuindu/i/se rolul unui inde% drisc pentru depresie ma orN (;elt5er / "##A)

G; are alori ariabile, ni elul scN5ut alacestei en5ime fiind e%presia unui stigmatgenetic al depresiei bipolare.


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Fn ciuda identificarii mar*erilor neurobiologici implicati in bolile neuropsihice(e%. depresia ma ora si dereglarile bipolare) diagnosticarea acestor boli se facepe ba5a simptomelor caracteristice asociate dereglarilor starilor psihice carepot include episoade alternante de cresteri e%treme ale starii de spirit (mania)si depresie se era. Fn mod e ident, in domeniul neurostiintelor se impunede5 oltarea unor metode de laborator pentru detectia si monitori5areaneurotransmitatorilor in scopul diagnosticarii clinice a dereglarilor ner oase.


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Dna dintre solutiile de perspecti a este repre5entata de posibilitatea utili5ariimicro/(bio)sensorilor pentru e aluarea neurotransmitatorilor, a caror proiectarepresupune un efort interdisciplinar ba5at pe de5 oltarea si proiectarea unor

nanotehnologii aferente micro/nanosistemelor integrate. &otentialul utili5ariimicro/(bio)sensorilor re5ulta din capacitatea acestora de a masura interactiiledintre sistemele nanosensorile si neurotransmitatori. ;icro/(bio)sensorii aucapacitatea de a detecta intr/un mod simplu, rapid, selecti si specificsubstantele de interes a and posibilitatea de a genera o informatie continua.


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&roiectarea micro(bio)sensorilor este unul din e%emplele eloc ente din domeniulcercetarilor interdisciplinare. bordarea stiintifica propusa pentru determinareaneurotransmitatorilor este una ino ati a care pleaca de la metodele clasice de analichimica. &roiectarea unor instumente miniaturi5ate care retin sensibilitatea ridicataselecti itatea metodelor instrumentale de laborator sofisticate repre5inta o pro ocaranalitica ma ora. Fn cadrul tehnologiei propuse pentru detectia neurotransmitatorilofost folositi (bio)sensori rele anti din punt de edere clinic care au condus laidentificarea si detectia neurotransmitatorilor intr/un timp mult redus comparati cuorice alte metode clasice.


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e5ultatele obtinute au permis e aluarea unor neurotransmitatori din probereale si prin aceasta fac posibila corelarea acestora cu diagnosticarea unor bolineuropsihice (precum dereglari uni/ si bipolare). cestea au condus la o maibuna intelegere a noilor cerinte analitice, inclu5and noi parametri (biomar*erii)

care descriu si conduc la diagnosticare tulburarilor neuropsihice ele potconduce si la o de5 oltare clinica in domeniul diagnosticarii bolilor neuropsihicprin stabilirea corelatiilor clinice dintre concentratiile de neurotransmitatori dinprobe reale cu bolile neuropsihice. stfel, se pot identifica de5echilibrele inconcentratiile de neurotransmitatori, optimi5a do5area medicamentelor siidentifica rapid pacientii care raspund la medicamentatia prescrisa.


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urther wor* applications on real samples are under study

The al'eG ncreases o'r 'nderstanding of the disease processG Fdentifies transmitter deficits and malfunctions

G *ro ides ne! leads for dr'g disco eryG 5acilitates clinical de elopmentG ptimi5es dose selectionG Fdentifies drug respondersG apid identification of efficacy in small groups


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SWCNT0s diameter123453 6

Biliografie

A TEM ima&e o!SWCNTs

A theoreti"a# mode# o!SWCNTs


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7E SEM1 7ie#d Emission+un S"annin&

E#e"tron Mi"ros"o-)1 The Mi"ros"o-e Instrument1

*S8333,Ha.in& an a""e#eratin& .o#ta&e1

53 9:

7/ :a#entini; A/ Curu##i; S/ Or#andu""i; M/ L/ Terrano.a; and +/ Pa##es"hi; E#e"troana#)sis 533/

STM1S"annin& Tunne#in&

Mi"ros"o-)1Instrument

* ?eo# ?SPM 8523 ,I1 3/233 3/@33 nA$

E *:,1 3/233 3/@33 :

The FE-SEM investigationshowed a homogeneous anduniform SWCNT’s coatingon the W microwiresurface. n addition! theSWCNT’s de"osit a""ears"er"endiculalr# allignedand oriented on the Wmicroelectrode surfaces.

sho%s that theSWCNTs are or&ani(edin .er) %e## orientedand a##i&ned bund#es/


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SWCNT W modi!ied mi"roe#e"trodes !or theneurotransmitter dete"tion/

A!ter the .arious de-osition -ro"esses; the "entra# -ortion *about 5 "m #en&th, o! ea"h W %ire %a"oated %ith insu#atin& .arnish; %hereas the t%o ti-s *about 3/< "m #en&th, remainin& un"ser.ed; res-e"ti.e#); as the %or9in& e#e"trode sur!a"e and the e#e"tri"a# "onta"t %ith thee#e"tro"hemi"a# "e## s)stem/ The modi!ied e#e"trode ti-s %ere %ashed "are!u##) %ith doub#e dis%ater -rior to use !or measurements/ The e#e"tro"hemi"a# "e## %as assemb#ed as a "on.entiothree e#e"trode s)stem1 a %or9in& e#e"trode made o! W %ires @33 m in diameter "oated b)SWNTs$ an A& A&C# re!eren"e e#e"trode *Mode# >3< CP+ / !rom Ame# Mi#an; Ita#),;

"ounter e#e"trode/ A## e'-eriments %ere "arried out at room tem-erature/ Initia# ")"#i" .o#tammetre'-eriments %ere "arried out o.er the ran&e < 2333 m: s; %hi#e a s"an rate o! 233 m: s %ase.entua##) "hosen to sur.e) the beha.ior o! the .arious e#e"trodes bein& e.a#uated/

A## e'-eriments %ere "arried out at room tem-erature; %or9in& in a -hos-hate bu!!er so#ution*3/2M; -H =/3,/ C)"#i" :o#tammetr) *C:, and Di!!erentia# Pu#se :o#tammetr) *DPe'-eriments %ere -er!ormed under uies"ent "onditions; res-e"ti.e#)/ Initia# ")"#i" .o#tammetr)e'-eriments %ere "arried out o.er the ran&e < 233 m: s; %hi#e a s"an rate o! 233 m: s %ase.entua##) "hosen to sur.e) the beha.ior o! the .arious e#e"trodes bein& e.a#uated/ DP:measurements %ere "arried out %ith a -u#se am-#itude o!


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The sensiti.it) o! the SWCNT Wmodi!ied mi"ro%ires %as si&ni!i"ant#)better than that o! the "on.entiona# +CE*2F=/8< mA mo#2L "m 5,/

A si&na# noise ratio -er unit area o!


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7/ :a#entini; +/ Pa##es"hi; et a#/$E#e"troana#)sis 533/

The #o%er LODs %ere obser.eon#) in the -resen"e o! CarbonNanotubes and Carbon Nano!iberbased sensors/

and a#so to their a##i&nement; orientatioand nanometer s"a#e dimensions ab#e &arantee a dire"t and intime "onta"t%ith the a"ti.e "entre o! the en()mes;bio#o&i"a# mo#e"u#es and the bio"ata#)s

This is -robab#) re#ated to the hi&hernomina# sur!a"e area o! SWCNTs

*≈ @33 m5 &,$

http://www.news.uiuc.edu/WebsandThumbs/Strano,M/01stranogfx_b.jpg


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Figu"e . 1a0 s)#-s a FE5SEM mic"#g"a!) #fS6C%T7s c#ating #btained #n t)e SSE su"faces b*EPD met)#d8 Mec)anicall* induced small sc"atc)es"e ealed t)e inne" nan#st"uctu"e #f t)e de!#sit+c#ntaining bundles #f aligned nan#tubes8 T)eS6C%T7s de!#sit c#ated enti"el* t)e mic"#elect"#desu"face+ in f#"m #f a dense !ac9ed la*e" -it) a )ig)"#ug)ness8

T)e st"uctu"al c)a"acte"i&ati#n -as !e"f#"medb* Raman s!ect"#sc#!*+ and in Figu"e 2a+ at*!ical Raman s!ect"um -as als# "e!#"ted f#"t)e C%TSSE b* EPD+ t)at s)#-ed t)e t*!ical"adial b"eat)ing m#de 1RBM0 signals+ -)ic)indicate t)e !"esence #f S6C%Ts+ )a ing ana e"age diamete" #f ab#ut .8$ nm :.;8 T)etangential "egi#n #f Raman s!ect"a and IRs!ect"#sc#!* s)#-ed t)e inse"ti#n #f O< g"#u!s#n t)e functi#nalised S6C%T7s+ simila" t# t)#se"e!#"ted in #u" !"e i#us -#"9 :.;+ ia =O< !"e5t"eatment8

F8 >alentini+ ,8 Pallesc)i+ E8 L#!e& M#"ales+ S8 O"landucci+ E8 Tambu""i+ and M8 L8 Te""an# a+ Elect"#anal*sis 2??@+ acce!ted8


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F A

E F 2 1 2 3 2 J 2 B 2 K 2 ? 2 @

-J2 ->B

>2 3B K2

F A

2 1 2 3 2 J 2 B 2 K 2 ? 2 @ -12

->22

>2 12 32

J2 B2 K2

E F

1B

>B >2 B -B

-2 1B 2 2 1B 2 B2 2 ?B > 22

32

12

->2 -12

I

A

E+ >Au mi"roe#e"trode1 G 5 2 -2 1B 2 2 1B 2 B2 2 ?B

-? B -B 2

-1 B 2

1 B B 2

? B >2 2

>1 B

F A

F8 >alentini+ ,8 Pallesc)i+ et al8 Elect"#anal*sis 2??@+ acce!ted8


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0

0,2

0,4

0,9

0,$

"

400 $00 "200 "900 2000 2400 2$00 -200 -900 4000


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-2 32 -2 12 -2 >2 2 2 >2 2 12 2 32 2 J2 2 B2 B

>2 >B

121B

323B

J2J

E F

F

A

b'ffer

BmM AA

:E!ine!)"ine;+ M

Linear Re&ression E uation1) A G2/35 2/@5 ' M$ *R5 G 3/FF>,Linear ran&e o! "on"entration1 5/3 ' 23 2/3 ' 23 8 *M,

L/O/ D/G *@ Kσ ,G 5/3 ' 23 *M,Sensiti.it) *A M 2 "m 5, G 5>/2RSD *n G 8, G =/3Res-onse Time G *s,

F8 >alentini+ ,8 Pallesc)i+ E8 L#!e& M#"ales+ S8 O"landucci+ E8 Tambu""i+ and M8 L8 Te""an# a+ Elect"#anal*sis 2??@+ acce!ted

-er!ormed at SWCNT modi!iedstain#ess stee# mi"roe#e"trodes;b) DP:/

http://www.brooklyn.cuny.edu/bc/ahp/MBG/MBG4/Enzymes.02.GIF


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7un"tiona#isedSWCNTs

En()mes1 the L +#utamate O'idase

http://www.brooklyn.cuny.edu/bc/ahp/MBG/MBG4/Enzymes.02.GIF


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PP) +O'

PP) +O'

PP) +O'

2PP) +O

'

PP) +O'

1

2/ The SWCNT de-osition b) EPD5/ One Ste- e#e"tro"hemi"a#

"o de-osition o! PP) and+O'*the bio"ata#)st,/

WE1 SWCNT Au mi"ro%ires; G 5


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This 7i&ure sho%s ahomo&eneous; uni!orm; anddense -a"9ed "oatin& on theentire Au mi"roe#e"trodesur!a"es/

A hi&her ma&ni!i"ation; the-o#)meri" #a)er a--ears as#ar&e and "om-a"t obu#astru"tures; ran&in& !rom 2<to 3 m/

Th H)d d) i" #t t )


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-122

2

12

J2

K2

@2

>22

>12

-K22 -322 322 K22 I22 >122

E.m /

. A /

A'.&2 12 32 J2 B2 K2 ?2 @2 I2 >22 >>2

F

A

2

>

1

3

J

B

K

?

@I

y F A = 2 >II 2 2?I x F mM

%1 = 2 III

2 > mM Acetaminophen

Linear Ran&e o! Con"entration18 233 mM*=3 2>33 m& d#,$L/O/D/G233 M *2/> m& d#, *L/O/D/ G *@'σ )3, a,$) A G *)3 σ )3, *a σ a,K' mM) G *3/2FF 3/33@, *3/3=F 3/33 ,K'$ R5G3/FFF$Sensiti.it)1 5/3 A mM 2 "m 5$RSD *n G @,1 <Res-onse Time1 23 s


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These nanostru"tured modi!ied mi"rosensorsare suitab#e !or a sensiti.e *usin& a##i&ned anoriented SWCNTs, and se#e"ti.e *usin&!un"tiona#ised SWCNTs, neurotransmittersdete"tion/

%i## be "arried outto immobi#i(e the L +#utama

O'idase en()me on the SWCNT modi!iedmi"roe#e"trodes to assemb#e sensiti.eneurotransmitter biosensors !or the ear#)dete"tion o! "ate"ho#amines in.o#.ed in somet)-i"a# neuro#o&i"a# disorders/

Typical LOD al'es .ngFL/ of ario's techni 'es for


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determination of ne'rotransmitters

Techni 'e 1CR luor microdial

>&1CR C 1accaseelectrode

C R luor microdial

Serotonin A(-0 p;)

"2000

Borepinephrine 2 4000

'opamine 2(20 p;)

2000$ µ ;

pinephrine 2"0 µ ;

6lutamate, spartate 0." µ ;

"c2ematic 3resentation o


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Molecular Imprintin#

R ;onomers

;olecularlyimprintedpolymer

!ashing

&olymer Targetmolecule

7inding

lution6inding)

&ynthesis)


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6 neurot prezentari

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