7/30/2019 Task4 Vitaminc Hplc New
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TASK 4: HPLC Analysis of Vitamin C in Tablets
Introduction
In the pharmaceutical industry, HPLC is routinely employed to
analyze drug products. The manufacturer MUSTensure that each
product meets the label claim for amount of drug present and each
dosage unit (tablets, capsules,
etc.) MUST have a consistent amount of drug present. As the
quality control analyst, you will be analyzing some
Vitamin C (ascorbic acid) tablets to ensure they meet the label
claim and that we have a consistent amount ofVitamin C in each
tablet.
Instrument Set-Up
Use the SpectraPhysics High Performance Liquid Chromatograph
(HPLC 3) system equipped with a C-18 reversephase column, a 20 ul
sample loop and a UV-Vis Detector connected to the Varian Star
Chromatography data
system.
Mobile Phase Preparation
Prepare 500 ml of a solution of 95 % water: 5 % methanol and add
6 drops of 6 M H2SO4.
Filter mobile phase and degas using vacuum filtration.
Press Run on pump module to pump mobile phase through HPLC at a
flow rate of 1 ml/min.
Wavelength Max for Vitamin C
Fill a cuvet with the 0.05 mg/ml Vitamin C standard and
determine the wavelength of maximum absorbance
for Vitamin C using one of the scanning UV/Vis
spectrophotometers. Use this wavelength for your absorbance
readings for your detector.
Press Status and scroll down arrow and press + or to select
range of 3.0 on detector module
Vitamin C (Ascorbic Acid) Standard Preparation
Prepare a 0.20 mg/ml Vitamin C standard diluted with water.
Prepare a 0.15 mg/ml Vitamin C standard diluted with water
Prepare a 0.10 mg/ml Vitamin C standard diluted with water.
Prepare a 0.05 mg/ml Vitamin C standard diluted with water.
Sample Preparation Five tablets have been pulverized and labeled
A, B, C, D, and E and record masses for each tablet
Dissolve 300 mg (mass to nearest 0.1 mg) in water and dilute to
100.0 ml of water. Do NOT heat solution.
Take a 10.00 ml aliquot of above solution and dilute to 100.0 ml
with water
Repeat for the other four additional tablets.
Analysis of Vitamin C
NOTE: Filter each solution prior to injecting with a syringe
filter.
Enter your name for Operator Name under instrument configuration
for Instrument 1.
Open method SpectraPhysics_start and copy to your own method
name and then modify your method as
necessary. Select Inject Single Sample on Star WorkStation and
enter Sample Name then select Inject
Flush sample loop with 1 ml of standard solutions and inject
into the HPLC.
Flush sample loop with 1 ml of filtered samples of Vitamin C and
inject into the HPLC. (Use syringe filter)
Result Calculations
Prepare a calibration curve and determine concentration of
Vitamin C in each sample solution
Calculate mass of Vitamin C in each of the five tablets as
follows:
= concentration (mg/mL) x100 mL x100 mL x tablet mass (mg)
10 mL x sample mass (mg)
Calculate the relative standard deviation and average for the
five sample results.
