research article growth and characterization of agar gel...

Research ArticleGrowth and Characterization of Agar Gel GrownBrushite Crystals

V B Suryawanshi and R T Chaudhari

Physics Research Lab Shri V S Naik Arts Commerce and Science College Raver 425508 India

Correspondence should be addressed to V B Suryawanshi vbsuryawanshi2007rediffmailcom

Received 27 October 2013 Accepted 2 December 2013 Published 8 January 2014

Academic Editors A Cremades and A D Yadav

Copyright copy 2014 V B Suryawanshi and R T Chaudhari This is an open access article distributed under the Creative CommonsAttribution License which permits unrestricted use distribution and reproduction in any medium provided the original work isproperly cited

Brushite [CaHPO4sdot2H2O] or calcium hydrogen phosphate dihydrate (CHPD) also known as urinary crystal is a stable form

of calcium phosphate The brushite crystals were grown by single and double diffusion techniques in agar-agar gel at roomtemperature Effects of different growth parameterswere discussed in single diffusion anddouble diffusion techniques Good qualitystar needle platy rectangular and prismatic shaped crystals in single diffusion and nuclei with dendritic growth were obtainedin double diffusion These grown nuclei were characterized by scanning electron microscopy (SEM) Fourier transform infrared(FTIR) spectroscopy X-ray diffraction (XRD) and thermogravimetric analysis (TGA) SEM has shown the different morphologiesof crystals FTIR has confirmed the presence of functional groups crystalline nature was supported by XRD whereas the TGAindicates total 2468 loss in weight and formation of stable calcium pyrophosphate (Ca

2P2O7) at 500∘C

1 Introduction

Calcium oxalates phosphates and their hydrates are verycommon in calcium renal stones Some of the oxalates arefound in either pure or in mixed form with phosphate andalso reported with uric acid or ammonium urates [1 2]Calcium oxalate monohydrate [3 4] and calcium oxalatedihydrate [5] are common constituents of calcium urinarycrystal while hydroxypatite [6] carbonate apatite [7] andbrushite [8ndash11] are in calcium phosphate crystals Brushite[CaHPO

4sdot2H2O] provides a medium to grow octacalcium

phosphate [12] and hydroxypatite [13ndash16] urinary crystalshowever used as a precursor to form apatite which has animportant application in bone formation [17 18]

Gel method is themost versatile and simple technique forgrowing urinary crystals [19ndash21] In this method gel acts asan inert and viscous medium for the growth of these crystals[22 23]

The growth inhibition study of brushite crystals arereported in silica gel by adding tamarind tartaric acid andcitric acid [24 25] and in the presence of sodium fluoride[26] Lim et al [27] have grown three-dimensional flowerlike brushite crystals from high internal phase emulsion

processing route whereas Kumar and Kalainathan [28] havegrown in the presence of magnetic field and observed theeffect on growth of these crystals Parekh et al [29] have alsoobserved the growth inhibition and dissolution of urinarytype micro-CHPD crystals Most of the brushite crystalsreported are grown in silica hydrogel however the growth ofthese crystals is not reported in agar-agar gel

In the present work the brushite crystals were grown inagar-agar gel at ambient temperature and were characterizedby scanning electron microscopy (SEM) Fourier transforminfrared (FTIR) spectroscopy X-ray diffraction (XRD) andthermogravimetric analysis (TGA)

2 Experimental

In the present study brushite crystals were grown by singleand double diffusion techniques [30] In this method glasstest tubes of size 15 cm in length and 18 cm in diameter andU-tube of size 25 cm in length and 25 cm in diameter wereused as crystallization vessels Agar gel (Himedia) solutionwas prepared by themixing (025 to 10 gm) of agar powder in100mL double distilled water at boiling temperature Potas-sium dihydrogen phosphate (KDP) (Merck) of concentration

Hindawi Publishing CorporationIndian Journal of Materials ScienceVolume 2014 Article ID 189839 6 pageshttpdxdoiorg1011552014189839

2 Indian Journal of Materials Science

Figure 1 Brushite crystals with controlled nucleation in singlediffusion

Table 1 Optimum conditions for the growth of brushite crystals

Condition Single diffusion Double diffusion of gel 05 10Con of calcium chloride 1M 1MCon of KDP 1M 1MGel setting period 24 hrs 24 hrsGel aging 48 hrs 48 hrsPeriod of growth 60 days 80 daysTemperature Room temp Room tempQuality Transparent Opaque

Shapestar needle platyrectangular andprismatic shaped

Dendritic shaped

05ndash10M and calcium chloride (Qualigens) of concentration05ndash10M were used as reactants

For single diffusion techniques the agar solution wasmixed with the desired concentration and appropriate vol-ume of calcium chloride After setting and aging of gel anaqueous solution of KDP was poured over the gel No precip-itation was observed however after 1ndash8 days nucleation wasseen at the interstitial and inside the gel

The samemethodwas repeated by reversing the reactantsBut no nucleation was observed in this method

In double diffusion agar solution was poured in U tubeup to appropriate height After setting and aging of gel anaqueous solution of KDP was poured in one limb whilein other limb an aqueous solution of calcium chloride waspoured over the gel As both the solutions diffused in thegel nucleation was observed after 10 days This nucleationwas further increased and took two months for its completegrowth After twomonths well-shaped brushite crystals weregrown inside the gel as shown in Figure 2

(a)

(b)

(c)

Figure 2 Harvested star needle platy rectangular and prismaticshape brushite crystals

These grown crystals were harvested from test tubes andwere characterized by SEM FTIR XRD and TGA

3 Result and Discussion

31 Growth In single diffusion technique many researchers[9 17 31] have observed Liesegang ring phenomena in silicagel however no Liesegang ring phenomena is observed inthe present study After diffusion of supernatant in the gelheavy nucleationwas observed To control nucleation variousparameters such as concentration of gel concentration ofreactant aging of gel and volume of reactants were changedwhich can be seen in Figure 1 and thus optimum conditionsare established as shown in Table 1 Figure 2 shows some goodquality star needle and transparent prismatic platy shapedcrystals grown in single diffusion

In double diffusion technique nucleation was startedafter diffusion of both reactants in gel This growth canbe seen in Figure 3 and their optimum conditions are

Indian Journal of Materials Science 3

Figure 3 Growth of brushite crystal in double diffusion

(a)

(b)

Figure 4 20X image of brushite crystals grown in double diffusion(a) dendratic shaped (b) edge growth

shown in Table 1 Interesting phenomenon was observed incase of crystals grown in double diffusion After formationof crystals the growth was again started from edges andfound in dendratic shape Figure 4(a) shows the 20X imageof dendratic shaped brushite crystals in double diffusionFigure 4(b) shows that a bulk nucleus is surrounded by severaltiny nuclei at the interstitial but not at the centre This onecan be easily understood by considering free energy changesassociated with the formation of nuclei and association ofseveral tiny nuclei at the edges may be due to the reason thatthe surface molecules are less well bound to their neighborsthan are those in bulk [32]

(a)

(b)

Figure 5 SEM images of brushite crystals (a) plate shaped and (b)crowded rod shaped morphology

32 Characterization

321 Scanning Electron Microscopy The morphology of thecrystals can be observed by SEM as shown in Figures 5(a)and 5(b) These figures show that the crystals are platyshaped and crowded by making some angles with c-axis InFigure 5(a) microrectangular plate shape placed over theother morphology can be seen Whereas Figure 5(b) showsthat rods are inclined and crowded The reason of formationof platy shape may be due to the growth of crystals in twodimensions

322 Fourier Transform Infrared Spectroscopy Figure 6shows the recorded FTIR spectrum of brushite crystal

The absorption peaks at 354142 cmminus1 [33 34] and315179 cmminus1 [9] are attributed to OndashH stretchingThe peak at164919 cmminus1 [35] is assigned to that ofOndashHbending whereasthe weak absorptions at 239567 and 176685 are associatedto HPO

4

2minus [9] while stretching vibrations associated withP=O were observed at 121519 112647 and 106281 cmminus1 [17]The PndashOndashP asymmetric stretching vibrations give rise toabsorptions at 98759 86221 and 80820 cmminus1 [17] Twobands at 58059 and 52080 cmminus1 are due to acid phosphate(HndashOndash) P=O bond vibration [17 36] FTIR spectroscopyconfirmed the growth of brushite crystals due to the presenceof water of crystallization P=O bond andOndashHbond [9]Theassigned vibrations with observed wave numbers are given inTable 2


75

70

65

60

55

50

45

40

4000 3500 3000 2500 2000 1750 1500 1250 1000 750 500

354142

315179

282195

239567

228572

212755

176685

164919

121519

112647

106281

98759

86221

80820

65196

58059

52080

42435

T(

)

1(cm)

Figure 6 FTIR spectrum of brushite crystals

Table 2 FTIR wave numbers and vibrations assignment of brushitecrystal

Sr no Observed wavenumber in cmminus1 Bondsvibrational assignments

1 354142 OndashH stretching of water2 315179 OndashH stretching of water3 239567 Weak absorption HPO4

2minus

4 176685 Weak absorption HPO42minus

5 164919 HndashOndashH symmetric bending vibrations

6 121519 PO4 P=O associated stretchingvibrations

7 112647 PO4 bond P=O stretching vibrations8 106281 PO4 bond P=O stretching vibrations9 98759 PndashOndashP asymmetric stretching bond10 86221 PndashOndashP asymmetric stretching bond11 80820 PndashOndashP asymmetric stretching bond12 58059 (HndashOndash) P=O bond acid phosphate13 52080 (HndashOndash) P=O bond acid phosphate

323 X-Ray Diffraction The X-ray diffractogram of the gelgrown brushite crystal is shown in Figure 7 The crystallinephases and 119889-values obtained from the XRD pattern havebeen compared with those in the JCPDS data The XRDpattern of Figure 7 matched with the JCPDS files [37 38]indicating that the sample consisted of brushite crystallineTable 3 gives the position 119889-values and matching peaks ofthe brushite crystals Figure 8 shows plot identified phases ofbrushite crystal

324 Thermogravimetry Figure 9 shows the thermogram ofbrushite crystals recorded in the temperature range 50ndash710∘Cat the rate of 1000∘Cmin The curve shows weight loss intwo stages First stage is dehydration of brushite crystals Ithas been observed that 35 of hydration of brushite is lostbetween 75∘C to 125∘C and 59 and is lost from 125∘C to200∘C whereas 6 is lost from 200∘C to 300∘C The totaldehydration is done between 100∘C and 300∘C Based upon

Cou

nts

40

20

0

10 20 30 40 50 60 70 80 90

Search unit cell result 1Search unit cell result 2

2103 BR-3

020

112

21

-111

-220

-2

02

-232

-1

32

-3

Position (2120579) (deg)

Figure 7 Powder diffractogram of brushite crystals

Peak list

00-009-0077

00-001-0395

20 30 40 50 60 70 80 90


Figure 8 Plot of identified phases of brushite crystals

90

80

70

60

50

40

30

20

10

0

50 100 150 200 250 300 350 400 450 500 550 600 650 700

Temperature (∘C)

Weight ()Weight ()

Wei

ght (

)

100169850000

∘C

100000∘C

973414

999766

200000∘C

812805300000

∘C800531

1231172

400000∘C

773426

475

500000∘C

753003

600000∘C

700000∘C

750858

751747

Figure 9 Thermogram of brushite crystals


Table 3 The XRD data of brushite crystal

Pos (2120579) (deg) Height (cts) FWHM (2120579) (deg) 119889-spacing (A) Rel int () Matched by117472 791 02952 752726 1548 001-0395 [37] 009-0077 [38]209844 413 02952 423006 807 001-0395 [37] 009-0077 [38]235421 955 02952 377594 1869 009-0077 [38]293470 1526 03444 304092 2985 001-0395 [37] 009-0077 [38]304833 703 03936 293012 1375 001-0395 [37] 009-0077 [38]342373 1161 02952 261693 2272 001-0395 [37] 009-0077 [38]356589 496 05904 251580 970 009-0077 [38]418101 315 05904 215879 617 001-0395 [37] 009-0077 [38]479518 1964 02952 189564 3843 009-0077 [38]503254 1482 02952 181166 2899 001-0395 [37] 009-0077 [38]508203 5111 02952 179517 10000 009-0077 [38]639728 874 02952 145417 1710 001-0395 [37]

the formula of brushite the theoretical mass loss for thedehydration of brushite is 2093 [39] The observed massloss for the dehydration of brushite crystals due to the firstthree steps is 1993 The following reaction is expectedduring the complete dehydration of brushite crystals andformation of monocite [17 39]

CaHPO4sdot 2H2O 997888rarr CaHPO

4sdotH2O +H

2O

CaHPO4sdotH2O 997888rarr CaHPO

4+H2O

(1)

In the second stage at higher temperature between300∘C to 500∘C two molecules of CaHPO

4combine and

result in the decomposition that occurs with the eliminationof water molecules leading to the formation of calciumpyrophosphate (Ca

2P2O7) [9 17 39] and then the sample

remains stable up to 75 The theoretical mass loss for thisstep is 52 [39] where as the observed mass loss is 475A possible reaction for the decomposition and formation ofcalcium pyrophosphate is

2CaHPO4997888rarr Ca

2P2O7+H2O (2)

4 Conclusions

The brushite crystals were grown by single and double diffu-sion techniques using agar-agar gel as a medium of growthDifferent morphologies namely star platy rectangular andprismatic shapes in single diffusion and dendratic growthin double diffusion were obtained The presence of variousfunctional groups is confirmed by FTIR spectroscopy X-ray diffraction spectra have confirmed the crystalline natureThe proposed chemical formula and crystal structure forthe grown sample are in good agreement with the resultsobtained from TGA studies

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgments

The authors are thankful to the Principal of Shri V S NaikArts Commerce and Science College Raver (M S) forproviding laboratory facilities thankful to Dr P V DalalShri V S Naik College Raver for fruitful discussion andthankful to the Director of SICART (Gujarat) for providingcharacterization facilities

References

[1] A Trinchieri C Castelnuovo R Lizzano and G Zanetti ldquoCal-cium stone disease a multiform realityrdquo Urological Researchvol 33 no 3 pp 194ndash198 2005

[2] R B Doddametikurke S B Chandra J Anthony and C JJ Browning ldquoThe role of Urinary Kidney Stone inhibitorsand promoters in the pathogenesis of calcium containing renalstonesrdquo European Association Urology vol 5 pp 126ndash136 2007

[3] D Valarmathi L Abraham and S Gunasekaran ldquoGrowth ofcalcium oxalate monohydrate crystal by gel method and itsspectroscopic analysisrdquo Indian Journal of Pure and AppliedPhysics vol 48 no 1 pp 36ndash38 2010

[4] E K Girija G R Sivakumar S Narayana Kalkura P Ramas-amy D R Joshi and P B Sivaraman ldquoKnoop microhardnessstudies of urinary calculi and pure calcium oxalate monohy-drate crystalsrdquo Materials Chemistry and Physics vol 63 no 1pp 50ndash54 2000

[5] M S Ansari N P Gupta A K Hemal et al ldquoSpectrum of stonecomposition structural analysis of 1050 upper urinary tractcalculi from northern Indiardquo International Journal of Urologyvol 12 no 1 pp 12ndash16 2005

[6] B Parekh M Joshi and A Vaidya ldquoCharacterization andinhibitive study of gel-grown hydroxyapatite crystals at phys-iological temperaturerdquo Journal of Crystal Growth vol 310 no7ndash9 pp 1749ndash1753 2008

[7] M Menon B G Parulkar and G W Drach ldquoUrinary lithiasisetiology diagnosis and managementrdquo Campbellrsquos Urology vol3 pp 2661ndash2733 1998

[8] K C Joseph and M J Joshi ldquoThe study of different param-eters affecting Liesegang ring formation during the growth ofcalcium hydrogen phosphate dihydrate crystalsrdquo Indian Journalof Physics vol 76 pp 159ndash163 2002


[9] V S Joshi and M J Joshi ldquoFTIR spectroscopic thermal andgrowth morphological studies of calcium hydrogen phosphatedihydrate crystalsrdquo Crystal Research and Technology vol 38 no9 pp 817ndash821 2003

[10] C Y C Pak K Rodgers J R Poindexter and K Sakhaee ldquoNewmethods of assessing crystal growth and saturation of brushitein whole urine effect of pH calcium and citraterdquo Journal ofUrology vol 180 no 4 pp 1532ndash1537 2008

[11] A E Krambeck S E Handa A P Evan and J E LingemanldquoBrushite stone disease as a consequence of lithotripsyrdquo Uro-logical Research vol 38 no 4 pp 293ndash299 2010

[12] S Mandel and A C Tas ldquoBrushite (CaHPO4 sdot 2H2O) to octa-calcium phosphate (Ca8(HPO4)2(PO4)4 sdot 5H2O transformationin DMEM solution at 365∘CrdquoMaterial Science and EngineeringC vol 30 no 2 pp 245ndash254 2010

[13] W F Neuman T Y Toribara and B J Mulryan ldquoSynthetichydroxyapatite crystals I Sodium and potassium fixationrdquoArchives of Biochemistry and Biophysics vol 98 no 3 pp 384ndash390 1962

[14] C Y Pak E D Eanes and B Ruskin ldquoSpontaneous precipita-tion of brushite in urine evidence that brushite is the nidus ofrenal stones originating as calcium phosphaterdquo Proceedings ofthe National Academy of Sciences of the United States of Americavol 68 no 7 pp 1456ndash1460 1971

[15] T K Anee M Palanichamy M Ashok N Meenakshi Sun-daram and S N Kalkura ldquoInfluence of iron and temperatureon the crystallization of calcium phosphates at the physiologicalpHrdquoMaterials Letters vol 58 no 3-4 pp 478ndash482 2004

[16] N Temizel G Girisken and A C Tas ldquoAccelerated transfor-mation of brushite to octacalcium phosphate in new biomin-eralization media between 365∘C and 80∘Crdquo Materials Scienceand Engineering C vol 31 no 5 pp 1136ndash1143 2011

[17] K Rajendran and C Dale Keefe ldquoGrowth and characterizationof calcium hydrogen phosphate dihydrate crystals from singlediffusion gel techniquerdquo Crystal Research and Technology vol45 no 9 pp 939ndash945 2010

[18] M P Binitha and P P Pradyumnan ldquoDielectric property studiesof biologically compatible brushite single crystals used as bonegraft substituterdquo Journal of Biomaterials andNanobiotechnologyvol 4 pp 119ndash122 2013

[19] A R Patel and A Venkateswara Rao ldquoCrystal growth in gelmediardquo Bulletin of Materials Science vol 4 no 5 pp 527ndash5481982

[20] N Srinivasan and S Natarajan ldquoGrowth of some urinarycrystals and studies on inhibitors and promoters I Standard-isation of parameters for crystal growth and characterization ofcrystalsrdquo Indian Journal of Physics vol 70 pp 563ndash568 1996

[21] G R Sivkumar E K Girija S Narayana Kalkura and CSubramanian ldquoCrystallization and characterization of calciumphosphates brushite and monetiterdquo Crystal Research and Tech-nology vol 33 no 2 pp 197ndash205 1997

[22] J Ouyang S Deng X Li Y Tan and B Tieke ldquoEffects of tem-perature and sodium carboxylate additives onmineralization ofcalcium oxalate in silica gel systemsrdquo Science in China B vol 47no 4 pp 311ndash319 2004

[23] T Bretherton and A Rodgers ldquoCrystallization of calciumoxalate in minimally diluted urinerdquo Journal of Crystal Growthvol 192 no 3-4 pp 448ndash455 1998

[24] K C Joseph B B Parekh andM J Joshi ldquoInhibition of growthof urinary type calcium hydrogen phosphate dihydrate crystalsby tartaric acid and tamarindrdquo Current Science vol 88 no 8pp 1232ndash1238 2005

[25] B B Parekh and M J Joshi ldquoCrystal growth and dissolutionof brushite crystals by different concentration of citric acidsolutionsrdquo Indian Journal of Pure and Applied Physics vol 43no 9 pp 675ndash678 2005

[26] C Sekar and K Suguna ldquoEffect of H3PO4reactant and NaF

additive on the crystallization and properties of brushiterdquoAdvanced Material Letters vol 2 no 3 pp 227ndash232 2011

[27] H Lim A Kassim N Huang P Khiewc and W Chiu ldquoThree-dimensional flower-like brushite crystals prepared from highinternal phase emulsion for drug delivery applicationrdquo Colloidsand Surfaces A vol 345 no 1ndash3 pp 211ndash218 2009

[28] A R Kumar and S Kalainathan ldquoEffect of magnetic fieldin the microhardness studies on calcium hydrogen phosphatecrystalsrdquo Journal of Physics and Chemistry of Solids vol 71 no10 pp 1411ndash1415 2010

[29] B B Parekh M J Joshi and A D B Vaidya ldquoModification ofgel technique for micro-crystals of biomaterials in situ growthand dissolution studiesrdquo Current Science vol 93 no 3 pp 373ndash378 2007

[30] H K Henisch Crystals in Gels amp Liesegang Rings CambridgeUniversity Press Cambridge UK 1988

[31] G Madhurambal R Subha and S C Mojumdar ldquoCrystal-lization and thermal characterization of calcium hydrogenphosphate dihydrate crystalsrdquo Journal of Thermal Analysis andCalorimetry vol 96 no 1 pp 73ndash76 2009

[32] J J de Yoreo and P Vekilov ldquoPrinciples of crystal nucleation andgrowthrdquo Crystal Growth vol 35 pp 24ndash30 2008

[33] S M Arifuzzaman and S Rohani ldquoExperimental study ofbrushite precipitationrdquo Journal of Crystal Growth vol 267 no3-4 pp 624ndash634 2004

[34] P V Dalal K B Saraf and S Shah ldquoGrowth of barium oxalatecrystals in agar-agar gel and their characterizationrdquo CrystalResearch and Technology vol 44 no 1 pp 36ndash42 2009

[35] P V Dalal and K B Saraf ldquoGrowth and study of barium oxalatesingle crystals in agar gelrdquo Bulletin of Materials Science vol 29no 5 pp 421ndash425 2006

[36] B M Borah H Lakshmi and G Das ldquoBiomimetic modulationof crystal morphology using gel from nano to micron-scalearchitecturesrdquoMaterials Science and Engineering C vol 28 no7 pp 1173ndash1182 2008

[37] Joint Committee for Powder Diffraction Standards (JCPDS)Reference Card Number 001-0395


[39] R L Frost and S J Palmer ldquoThermal stability of the ldquocaverdquomineral brushite CaHPO

4sdot2H2Omdashmechanism of formation

and decompositionrdquo Thermochimica Acta vol 521 no 1-2 pp14ndash17 2011

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of



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CompositesJournal of

NanoparticlesJournal of



International Journal of

Biomaterials


NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014


CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research



MetallurgyJournal of


BioMed Research International

MaterialsJournal of


Nano

materials


Journal ofNanomaterials


Figure 1 Brushite crystals with controlled nucleation in singlediffusion

Table 1 Optimum conditions for the growth of brushite crystals

Condition Single diffusion Double diffusion of gel 05 10Con of calcium chloride 1M 1MCon of KDP 1M 1MGel setting period 24 hrs 24 hrsGel aging 48 hrs 48 hrsPeriod of growth 60 days 80 daysTemperature Room temp Room tempQuality Transparent Opaque

Shapestar needle platyrectangular andprismatic shaped

Dendritic shaped

05ndash10M and calcium chloride (Qualigens) of concentration05ndash10M were used as reactants

For single diffusion techniques the agar solution wasmixed with the desired concentration and appropriate vol-ume of calcium chloride After setting and aging of gel anaqueous solution of KDP was poured over the gel No precip-itation was observed however after 1ndash8 days nucleation wasseen at the interstitial and inside the gel

The samemethodwas repeated by reversing the reactantsBut no nucleation was observed in this method

In double diffusion agar solution was poured in U tubeup to appropriate height After setting and aging of gel anaqueous solution of KDP was poured in one limb whilein other limb an aqueous solution of calcium chloride waspoured over the gel As both the solutions diffused in thegel nucleation was observed after 10 days This nucleationwas further increased and took two months for its completegrowth After twomonths well-shaped brushite crystals weregrown inside the gel as shown in Figure 2

(a)

(b)

(c)

Figure 2 Harvested star needle platy rectangular and prismaticshape brushite crystals

These grown crystals were harvested from test tubes andwere characterized by SEM FTIR XRD and TGA

3 Result and Discussion

31 Growth In single diffusion technique many researchers[9 17 31] have observed Liesegang ring phenomena in silicagel however no Liesegang ring phenomena is observed inthe present study After diffusion of supernatant in the gelheavy nucleationwas observed To control nucleation variousparameters such as concentration of gel concentration ofreactant aging of gel and volume of reactants were changedwhich can be seen in Figure 1 and thus optimum conditionsare established as shown in Table 1 Figure 2 shows some goodquality star needle and transparent prismatic platy shapedcrystals grown in single diffusion

In double diffusion technique nucleation was startedafter diffusion of both reactants in gel This growth canbe seen in Figure 3 and their optimum conditions are



(a)

(b)



(a)

(b)


32 Characterization




4



75

70

65

60

55

50

45

40

4000 3500 3000 2500 2000 1750 1500 1250 1000 750 500

354142

315179

282195

239567

228572

212755

176685

164919

121519

112647

106281

98759

86221

80820

65196

58059

52080

42435

T(

)

1(cm)





2minus







Cou

nts

40

20

0

10 20 30 40 50 60 70 80 90


2103 BR-3

020

112

21

-111

-220

-2

02

-232

-1

32

-3



Peak list

00-009-0077

00-001-0395

20 30 40 50 60 70 80 90



90

80

70

60

50

40

30

20

10

0

50 100 150 200 250 300 350 400 450 500 550 600 650 700

Temperature (∘C)

Weight ()Weight ()

Wei

ght (

)

100169850000

∘C

100000∘C

973414

999766

200000∘C

812805300000

∘C800531

1231172

400000∘C

773426

475

500000∘C

753003

600000∘C

700000∘C

750858

751747







4sdotH2O +H

2O


4+H2O

(1)


4combine and





2P2O7+H2O (2)

4 Conclusions




Acknowledgments


References



















































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials





(a)

(b)



(a)

(b)


32 Characterization




4



75

70

65

60

55

50

45

40

4000 3500 3000 2500 2000 1750 1500 1250 1000 750 500

354142

315179

282195

239567

228572

212755

176685

164919

121519

112647

106281

98759

86221

80820

65196

58059

52080

42435

T(

)

1(cm)





2minus







Cou

nts

40

20

0

10 20 30 40 50 60 70 80 90


2103 BR-3

020

112

21

-111

-220

-2

02

-232

-1

32

-3



Peak list

00-009-0077

00-001-0395

20 30 40 50 60 70 80 90



90

80

70

60

50

40

30

20

10

0

50 100 150 200 250 300 350 400 450 500 550 600 650 700

Temperature (∘C)

Weight ()Weight ()

Wei

ght (

)

100169850000

∘C

100000∘C

973414

999766

200000∘C

812805300000

∘C800531

1231172

400000∘C

773426

475

500000∘C

753003

600000∘C

700000∘C

750858

751747







4sdotH2O +H

2O


4+H2O

(1)


4combine and





2P2O7+H2O (2)

4 Conclusions




Acknowledgments


References



















































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




75

70

65

60

55

50

45

40

4000 3500 3000 2500 2000 1750 1500 1250 1000 750 500

354142

315179

282195

239567

228572

212755

176685

164919

121519

112647

106281

98759

86221

80820

65196

58059

52080

42435

T(

)

1(cm)





2minus







Cou

nts

40

20

0

10 20 30 40 50 60 70 80 90


2103 BR-3

020

112

21

-111

-220

-2

02

-232

-1

32

-3



Peak list

00-009-0077

00-001-0395

20 30 40 50 60 70 80 90



90

80

70

60

50

40

30

20

10

0

50 100 150 200 250 300 350 400 450 500 550 600 650 700

Temperature (∘C)

Weight ()Weight ()

Wei

ght (

)

100169850000

∘C

100000∘C

973414

999766

200000∘C

812805300000

∘C800531

1231172

400000∘C

773426

475

500000∘C

753003

600000∘C

700000∘C

750858

751747







4sdotH2O +H

2O


4+H2O

(1)


4combine and





2P2O7+H2O (2)

4 Conclusions




Acknowledgments


References



















































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials








4sdotH2O +H

2O


4+H2O

(1)


4combine and





2P2O7+H2O (2)

4 Conclusions




Acknowledgments


References



















































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials













































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials



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