water, ph and buffer specific properties of water hydrogen binding, acidity, h +, ph and buffer
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Water, PH and buffer
Specific properties of water
Hydrogen binding,
Acidity, H+, PH and buffer
مبحث این آموزشی اهداف
: کلی آن اهداف مبحث این ارائه از هدف : دانشجو که است
•. نماید درک را بیوشیمی علم اصول
مفهوم • و آن حیاتی نقش آب، ویژه خواص
PH. بفهمد را
•. نماید درک را آن نقش و بافر ماهیت
: ویژه این اهداف آموزش از پس دانشجو رود می انتظارباشد قادر :مبحث
. نماید بندی تقسیم و تعریف را بیوشیمی علم. نماید فهرست را آن اجزاء اصلی نقش و بندی تقسیم را سلولها. نماید بندی تقسیم و تعریف را بیوملکولها. دهد توضیح را آن علل و آب معمول غیر خواص. نماید مقایسه را قطبی غیر و قطبی ترکیبات. دهد توضیح را هیدروفوبیک و هیدروژنی پیوندهای و هیدروژن یون غلظت محلول، یک اسیدیته .PHارتباط دهد شرح را. نماید مشخص را آن حیاتی اهمیت و نموده تعریف را بافر. نماید مشخص را آنها اهمیت و تعریف را ضعیف باز و اسید تفسیر را بافر تهیه با را آن ارتباط و ضعیف اسید تیتراسیون منحنی
نماید.. ببرد نام را بیولوژیک بافرهای
Biochemistry Biochemistry is the Chemistry of life(Gk ,bios “life” Area for study: cell biology, molecular biology and molecular
genetics Aim of Biochemistry: Describe and explain ,in molecular
terms ,all chemical process of living cells( exm. contractibility in muscle cells)
How life began Scope of biochemistry
Classification Medical biochemistry
• General biochemistry
• Clinical biochemistry
Interrelationship of biochemistry and medicine Two – way street(structure and function:
normal and sickle cell Hb,PKU,alkaptonuria,….)
Health All disease has a biochemical basis Treatment of disease Inborn error of disease
Water, PH and buffer
Example of the two-way street connecting bioch. And medicine
MEDICINE
LIPID
ATHERO-SCLEROSIS Diabetes mellitus
Carbohydrates
Biochemistry
proteins
Sickle cell anemia
Nucleic acids
Genetic disease
Normal biochemical processes are the basis of health
WHO and define of health Biochemical research has impact on
nutrition and preventive medicine
Water, PH and buffer
A knowledge of Biochemistry is essential to all life sciences
Genetic, Physiology Immunology Pharmacology& pharmacy Toxicology Pathology, Microbiology, Zoology, Botany RESUT; Biochemistry as common language
Human genome project(HGP)
Sequencing of human genome(1990,2000)
International human genome sequencing consortium and Celera Genomics
This project completed in 2003 (after 50ys discovery of ds DNA)
HGP had many effects on research Human genome project
HGP
PROTEOMICS
BIOTECNOLOGY
BIOETHICS
Synthetic biology
Molecular diagnosis
Stem cell biology
bioengineering
metabolomics
Cell as unit of life
Prokaryote Eukaryote Cell organelle
• Cell membrane
• Cytosol
• Nucleus
• Mitochondria
• Endoplasmic reticulum
• Golgi
Prokaryotic cell
Eukaryotic cell
Cell fractionation
Cell suspension (Blender) Cell homogenization (Poter) Cell extract Centrifugation
• Density gradient
• Sequential sedimentation
• Sequential floatation
Cell fractionation
Purification techniques
Simple centrifugation Salting out Ultracentrifugation Dialysis Electrophoresis Chromatography
• Gel filtration
• Ion exchange chromatography
• Affinity chromatography
Centrifugation
Column chromatography
Column chromatography
Paper chromatography
Paper Electrophoresis
Gel Electrophoresis
Dialysis
Water and pH TWO- THIRD OF TOTAL BODY WEIGHT(55-65%) IN MEN AND 10%
LESS IN WOMEN It is distributed in intracellular and extracellular fluid Regulation of water balance depends on hypothalamic
mechanism ADH(2% increase in extracellular fluid osmolarity) Kidney And others Non osmotic mechanism(10% decrease in extracellular volume Physiologic pH and buffer systems( bicarbonate, phosphate and
proteins)
Special properties of water
Water, the most vital molecule
• High melting point
• High boiling point
• High thermal content
• High dielectric constant
• …………………………..
Polar nature
Water
Hydrogen bonds
H-bonding of water molecules
Polar compounds
Polar (hydrophilic) molecules
Urea
Ionic (hydrophilic) molecules
Non-polar (hydrophobic) molecules
Water ionization
Ionization of water
H2O ↔ H+ + OH-
K= [H+] [OH-] / [H2O] = 1.8 × 10-16
K= [10-7][10-7]/[55.56]=1.8x10-16 mol/L
Kw =(K)[H2O]= [H+] [OH-] = 1 × 10-14
(1.8x10-16 mol/L)(55.56)=1X10-14(mol/l)2
PH = -log [H+]
PH + POH = 14
What is a Buffer?
introduction: Definition of acid or base Strong acid H2SO4 2H+ +SO4-2 Strong base NaOH Na+ +OH- Weak acid and base
What is a Buffer?
A buffer consists of a mixture of a weak acid and conjugated base.
An acid is a proton donor and base is a proton acceptor.
AH ↔ A- + H+
Proton donor ↔ proton acceptor
Weak acid ↔ conjugated base
HA A- + H+ Ka =[A-][H+]/[HA] [H+]=Ka[HA]/[A-] Log[H+]=log(ka [HA]/[A-]) Log[H+]=logka+log[HA]/[A-] -Log[H+]=-logka-log[HA]/[A-] pH=pKa+log[A-]/[HA]
Henderson – Haselbach equation
Henderson – Haselbach equation
Relation between PH and base to acid ratio described by Henderson – Haselbach equation.
Buffer capacity
Buffer systems tends to be most effective when the PH is equal to their weak acid PKa. (a range PKa±1)
More concentrated buffers are more effective.
Titration curve for weak acid
CH3COOH
CH3COOH
CH3COO-
CH3COO-
PK
Titration curve of weak acids
Titration curve of Glycine(amino acid)