Dimethyl dibenzylidene sorbitol (DMDBS) is one of the most commonly used nucleating agent in polypropylene formulations. In present study, a simple and robust reversed phase liquid chromatography (RP-LC) based analytical method was developed for the quantitative low-level determination of DMDBS. The best separation was achieved on a RP-HPLC column TSK gel G2000 SW, 7.5mm x 30cm, Particle Size 10 µm from TOSOH Bioscience. A 0.05 M NH4AC (pH = 6.6) + 10% ACN solution was used as mobile phase at a flow rate of 1.2 ml/min. UV detection was performed at 216 nm. Retention time was found to be 13.056 min. for DMDBS. The response was a linear function of concentration over the range of 2.00 to 8.00 µg/ml with correlation coefficient of 0.9996 for DMDBS. The LOD and LOQ for DMDBS were found to be 1.00 µg/mL and 2.00 µg/mL respectively. The method is simple, rapid and robust, which is suitable for application in quality control and can also be used for the estimation of DMDBS as a leachable/ extractable from polypropylene (PP) resin and resin products like medical device containers.

Abdus Salam