Question

How do I extract parabens from lotion for HPLC?

Answer 1

Solution:- OH Paraben Required Chemicals and Solutions: 1. Hand lotion sample. 2. Methylparaben stock standard solution. 3. Propylparaben stock standard solution. 4. Methanol 5. HPLC Grade acetonitrile (for mobile phase) 6.18 milliQ Water 7.4 standards with paraben concentrations between 5-50 ppm Sample Preparation: Typical paraben concentrations are 0.05-0.2% in commercial products. Assuming this, determine an appropriate means to disperse the lotion sample into a 70% methanol/water solvent to prepare a solution that has a paraben concentration in the range of 5-50ppm. Realize that the lotion may not dissolve completely, but efficient extraction of the parabens, which are soluble in methanol/water is key. Next, the sample must be filtered to remove particulates using a syringe filter with no larger than 0.45 um pore size. One should prepare 3 replicate samples Extraction:- In order to quantify the amount of paraben present in the lotion, you will need to prepare the appropriate standards and develop a calibration curve. Use the relative sizes of the paraben peaks in the stock solution and in your sample to determine the appropriate dilutions needed to prepare four standards whose concentrations bracket your sample. To save time, it may be advised to prepare a single set of standards that contains both parabens. Once the solutions are prepared, run injections of your standards and sample, as well as a blank to prepare your calibration curve. Run at least three injections of your sample to determine the precision of the method. Prepare a running calibration curve to be sure that things are proceeding as expected. Hernce , Using calibration curves created by both peak areas and peak height, determine the concentration paraben in the lotion sample.