120 likes | 222 Views
C o l o r i m e t r i c o f a s p i r i n determination. Acetyl salicylic acid. antiplatelet effect by inhibiting the production of thromboxane. purposes. d etermine the amount of aspirin in a commercial aspirin product.
E N D
Acetyl salicylic acid antiplatelet effect by inhibiting the production of thromboxane
purposes • 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.
principle ExxNaOH ∆ + Na acetate Na salicylate Neutralize Why? By what ? Conc.HCL FeCL3 To prevent form Fe(OH)3 Colored complex (violet) Intensity of color direct relationship with substance concentration
procedure Part I: making standard • 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 5mL 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