IPT02
MOISTURE IN HAND CREAM
Last Revised: May 2015 1. PURPOSE This exercise determines the water content in hand cream by GLC. 2. REAGENTS & EQUIPMENT 2.1 Standard (5 g/100 mL water and 15 g/100 mL ethanol in 2‐propanol, masses known exactly) 2.2 Hand cream 2.3 Ethanol 2.4 GLC with suitable column 3. PROCEDURE 3A. Sample preparation 3.1 In triplicate, weigh accurately about 7.5 g of sample into a 400 mL beaker. 3.2 To one of the samples, add 2 g of water, measuring the weight accurately. This is the recovery check. 3.3 Add 20 mL of anhydrous 2‐propanol (by measuring cylinder) and 8 g (weighed accurately) of anhydrous ethanol and blend until smooth. 3.4 Adjust the volume to approximately 100 mL with 2‐propanol. 3.5 Filter the mixture through a fluted #43 (or similar) filter paper. Discard the first 5 mL then retain the next 10 mL for analysis. 3B. Analysis 3.6 Obtain a water/ethanol standard and record the exact mass of the water and ethanol in it. 3.7 Inject 1 uL aliquots of the standard and samples. The elution order is water, ethanol and propanol. 3.8 Measure peak height for the water and ethanol peaks for each run. Reporting 
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Enter the data into the spreadsheet found on the subject website. Transfer the final results – average %w/w, relative precision and %recovery – to your Result Sheet and submit this.