colorimetric of aspirin determination. antiplatelet effect by inhibiting the production of...

Colorimetric of aspirin determination

antiplatelet effect by inhibiting the production of thromboxane

Acetyl salicylic acid

determine the amount of aspirin in a commercial aspirin product.

used to determine the purity of the aspirin produced in the Microscale Synthesis of Acetylsalicylic Acid lab.

purposes

principle

Exx NaOH

∆

+

FeCL3

Neutralize Why?

Colored complex (violet)Intensity of color direct relationship

with substance concentration

To prevent form

Fe(OH)3

By what? Conc.HCL

Na acetate

Na salicylate

Part I: making standard

procedure

Weight 0.4 g of acetyl salicylic acid (authentic powder)

and put in 100 ml beaker then Add 20 ml distilled water

then add 10 mL of a 0.5N NaOH then heat it on hot plate until

boiling then add 2 drops Ph.ph togive pink

color then add Conc. HCL to neutrlize

Quantitatively transfer the solution to a 250 mL volumetric

flask, and dilute with distilled water to the mark..

Pipet a 5 mL of standard solution to a 100 mL volumetric flask.

then add 5 ml of FeCL3 solution then complete to market with

distilled water.

Label the flask .

Part II: making sample

put one tablet in 100 ml beaker then add 20 ml distilled water by measure then add 5 ml of 0.5 N NaOH .

Heat it on hot plate until boiling the add 2 drops Ph.Ph. To give pink Color then add Conc. HCL to neutralize it .

Filtrate it onto volumetric flask 250 ml by using fitter paper and

Funnel then complete with distilled water (mix well)

Pipette 5ml of sample solution to 100 ml volumetric flask .

Add 5 ml of 5% FeCL3 solution then complete with distilled water To the market. ( mix well).

Label the flask.

Part III: making blank

Put 5 ml of FeCL3 to 100ml volumetric flask then complete

the volume by distilled water

Measure the absorbance at λ max 510 nm

Standard sample blank

Calculation

for standard

concentration of standard is 8 mg/100 ml (mg%)

ᶜᶬ A 1%

For sample

Calculated Conc. Practical Conc.

= 2 mg /100ml (mg%)

1-beers law.

2-matching point.

% recovery

(95-105)

Practicale calculated

According to the result we can say the tablet accepted or rejected

X100