1. Biochemistry lab. MEDI 2130 INTRODUCTION Islamic University_ Gaza
Faculty of Health Sciences.
Medical Technology Department.
Biochemistry lab.
MEDI 2130
INTRODUCTION

2. Biochemistry Biochemistry is the application of chemistry to
study biological processes at the cellular and molecular level.
Biochemistry is also concerned with the study of the structure and function of cellular components, such as proteins, carbohydrates and lipids.
Biochemistry is both a life science and a chemical science; it has provided explanations for the causes of many diseases in humans.

3. Biochemistry is the study of molecular structures and interactions in living organisms.
Biochemists seek to understand living organisms in terms of chemical reactions.

4. Biochemistry The objective of this course:
To learn fundamental techniques used in biochemistry.
To learn some biochemical procedures and experiments commonly used in biochemistry laboratories.
To provide a basis for understanding how biochemical data is obtained, analyzed and presented.

5. Attendance and activity15 HW 10
Reports
Quizzes 25
Final 40

6. Safety rules
1. Listen to or read instructions carefully before attempting to do anything.
2. Clean up your lab area at the conclusion of the laboratory period.
Wear lab coat

7. After handling chemicals, remove gloves and always wash your hands with soap and water.

8. Never taste any chemicals (you should never taste anything in the lab).

9. Sign for cautions
1. Corrosive: destructive to living tissue or to organic material (strong acid, strong base).
2. Irritant: only causes irritation to skin (mild acid, mild base).
3. Explosive: you have to know the kind of chemical materials.
4. Flammable: any petroleum derivative materials (ether, ethanol).
5. Radioactive substances: used in hormonal assays, isotopes.
6. Toxic: like toxicity caused by heavy metals (lead, mercury).
Please read the warning signs and symbols placed on the reagents.

10. Flammable liquids should be used on premises without ignited burners or other sources of open flames. They should be stored in tightly sealed vessels.

11. Chemical hazards
Never mix chemicals together unless you are told to do so (and then only in the manner specified).
Never pour water into a concentrated acid. Acid should be poured slowly into water.
Check labels on containers twice to make sure you use the right chemical and of the correct concentration. Dispose of chemicals in proper receptacle.

12. If you need to smell the odor of a
If you need to smell the odor of a chemical, waft the fumes toward your nose with one hand. Do not put your nose over the container and inhale the fumes.

13. Before leaving the lab, the workplace, reagents and equipment should be put in order.
Wash the lab glass. Close the gas valves. Turn off the taps.
Team work

14. Instruments

15. The only type of glassware that may safely be heated is either Kimax or Pyrex.
When heating a test tube, move it around slowly over the flame to distribute the heat evenly. Keep burners in the middle of the lab table, not on the edge. When heating liquids in test tubes, never point the tube toward yourself or anyone else.
Never heat the test tube directly at the bottom but tilt the tube and heat it gently between the bottom of the tube and the top of the liquid. Use boiling chips when boiling liquids in a flask or beaker to prevent bumping.

16. Droppers
Balance
cylinder
Filter paper

17. Test tube brush
Clamps
Rack

18. Centrifuge - separates materials of varying density.
Test tube - used as holder of small amount of solution.
Thermometer - measures temperature.
Wire gauze - used to spread heat of a burner flame.

19. burette - measures volume of solution.

20. Certainty vs. Uncertainty
The smallest division of this graduated cylinder is 1 mL. These values are CERTAIN. Note: There are no graduation lines between 36 and 37 mL. This value must be ESTIMATED.
The error in reading the measurement will be ± 0.1 mL or 1/10 of the smallest division.
A reading of the volume is: 36.5 ± 0.1 mL One person may read this as: 36.6 mL One person may read this as: 36.4 mL
NOTE: The value of 36 is CERTAIN The value of .5, .6 or .4 is ESTIMATED OR UNCERTAIN
The certainty of a measurement depends on the precision of the instrument.

21. Accuracy vs. Precision Accuracy
Accuracy is defined as the degree of conformity to the truth and expressed as absolute error.
Absolute error = experimentally measured value – true value
Precision is defined as the degree of agreement between replicate experiments and expressed as standard deviation.
Precision does not mean accuracy, since measurements may be highly precise but inaccurate due to a faulty instrument or technique.
(Most accurate) burettes > volumetric flasks > pipettes > graduated cylinders > graduated beakers (least accurate)

22. Solutions
Solutions are mixture of two or more substances in a single phase. One constituent is usually regarded as the SOLVENT (material that dissolves another substance) and the others as SOLUTES (substance being dissolved).
Solute + Solvent = Solution
One of the most common types of solutions involves a solid dissolved in a liquid.
There are several factors that affect the rate of solubility, or how quickly a solute dissolves (dissolution).
Ex: NaCl aqueous solution
NaCl is the solute Water ( H2O ) is the solvent
NaCl and water make up the solution
Solute: The solid, liquid or gas dissolved to make a solution.
Solvent: The solid, liquid or gas used to dissolve a solute to make a solution
Solution: Any combination of solute & solvent.

23. FACTORS AFFECTING SOLUBILITY
Solubility of a substance in a solvent can be affected by one or more of the following factors:
1. Nature of the solute 2. Nature of the solvent 3. Temperature 4. Pressure ( Affects gas solutes only.)

24. Nature of the Solute: Nature of the solvent:
Solubility can be affected by the “nature” of the solute.
Solutes can be polar or non-polar, ionic or molecular , soluble or insoluble etc.
For a given solvent, these solute properties can affect the ability of the substance to dissolve. Nature of the Solvent:
Nature of the solvent:
Solvents can be polar or non-polar, ionic or molecular etc.
For a given solute, these solvent properties can affect the ability of the solvent to dissolve the solute.

25. The concentration of a solution
It represents the amount of solute dissolved in a unit amount of solvent or of solution, and can be expressed in a variety of ways (qualitatively and quantitatively).
I. Qualitative Expressions of Concentration
A solution can be qualitatively described as
Diluted: a solution that contains a small proportion of solute relative to solvent, or
Concentrated: a solution that contains a large proportion of solute relative to solvent.

26. II. Quantitative Expressions of Concentration
Units of mass and volume:
The basic international unit of mass is the kilogram (kg) and that of volume is the liter (L). Frequently, fractions of these units are used instead. Mass units:
1 gram (g) = kg
1 milligram (mg) = g
1 microgram (g) = g

27. Volume units:
1 liter (L) = 1 dm3 (cubic decimeter)
1 deciliter (dL) = L = 100 mL
1 milliliter (mL) = L = 1 cm3 (cubic centimeter)
1 microliter (L) = L = 1 mm3 (cubic millimeter)

28. 2) Molar concentrations 3) Normality
Methods:
1) Percentages
2) Molar concentrations
3) Normality
4) Very low concentrations

29. 1) Percentages
Percentages Percent means parts per 100 It is expressed by two ways according to the nature of solvent: A -Percent / volume B. Percent by mass: Indicated % (W/W)

30. A -Percent / volume
It is further divided into 2 types according to the nature of solute:
Volume / Volume [Indicated % (v/v)], when the solute is liquid, = Volume of solute/ Volume of solution x 100. Less commonly used
Weight / Volume [Indicated % (w/v)], When the solute is a solid, = Mass of solute (g) / Volume of solution (mL) x 100. More commonly used.

31. volume/volume
Rubbing alcohol is generally 70% by volume isopropyl alcohol. That means that 100 ml of solution contains 70 ml of isopropyl alcohol.
That also means that a liter (or 1000 ml) of this solution has 700 ml of isopropyl alcohol plus enough water to bring it up a total volume of 1 liter, or 1000 ml.

32. B. Percent by mass: Indicated % (W/W)
Mass of solute (g) / Mass of solution (g) x 100%
What is the weight percent of glucose in a solution made by dissolving 4.6 g of glucose in g of water?
Analysis: To get weight percent we need the weight of the solute and the total weight of the solution.
Determine total weight of solution: 4.6 g g = g  
Calculate percent:
Weight % glucose =   4.6 g glucose  x 100 = 3.1% glucose g solution

33. How much solute is present in 756. 1 mL of a 14
How much solute is present in mL of a 14.7% (mass/volume) HCl solution?
Mass/volume % = (masssolute/volumesolution) 100
14.7 % = (x / mL ) 100
x = (756.1 mL)
x = mass of solute = 111g

34. II- Molarity (M):
- Another way of expressing concentration is called molarity. Molarity is the number of moles of solute dissolved in one liter of solution. The units, therefore are moles per liter, specifically it's moles of solute per liter of solution.
Molarity = moles of solute liter of solution

35. Rather than writing out moles per liter, these units are abbreviated as M or M.
M = wt X 1000
MW X Vml

36. Normality: N = moles of reactive units per liter (equivalents per liter).

37. Dilution:
- Diluted solutions can be prepared from concentrated solutions
M conc X V conc = M dil X V dil

38. Types of analysis
1. Qualitative chemistry provides information about the elemental make-up or a composition analysis of a test sample by identifying individual elements or groupings of elements found in the sample. The qualitative test process can be used for material identification and detection of impurities and contaminants in test samples.

39. Quantitative chemical analysis
2. Quantitative chemical analysis is performed to accurately determine the concentration, amount or percentage of one or more elements in a test sample.
This technique, along with qualitative analysis, provides information on what and how much of each element is present in a sample for a complete elemental analysis.
In chemistry, quantitative analysis is the determination of the absolute or relative abundance (often expressed as a concentration) of one, several or all particular substance(s) present in a sample.

40. chemical reaction
A chemical reaction :change of a substance into a new one that has a different chemical.
signs of chemical reaction:
1-formation of a precipitate
2-color change
3-evolution of gas
4-temperature change
Exothermic reaction :give off energy and generally cause the surroundings to get hotter
Endothermic reactions: require energy and generally cause the surrounding to become cooler

41. Types of biochemical compounds
Carbohydrates
Amino acids and proteins
Nucleotides and nucleic acids
Lipids

42. How to make report Name of test Aim Principle Procedure Results
Comments