Quick Detection of Contaminants Leaching from Polypropylene Centrifuge Tube with Surface Enhanced Raman Spectroscopy and Ultra Violet Absorption Spectroscopy

摘要

Anomalous surface enhanced Raman scattering (SERS) peaks are identified forliquid sample stored in polypropylene centrifuge tubes (PP tube) for months. Weobserved the unexpected Raman peaks during experiments for ThiamineHydrochloride aqueous solution stored in PP tube for two months. In order toidentify the contaminants we have performed SERS experiments for de-ionizedwater (DI water) stored in polypropylene centrifuge tube for two months andcompared them with fresh DI water sample. We have also carried out Ultra Violet(UV) absorption spectra for both fresh and contaminated water. We believe thatthe water is contaminated because of chemicals leaching from the PP tube. Fromthe GC-MS data the main contaminant was found to be Phthalic acid and itsderivatives. Further SERS and UV absorption experiment for Phthalic acidcorrelates well with the anomalous peaks identified earlier. We qualitativelyconfirmed the identification and quantitatively estimated the concentration ofsuspect contaminants as between 1uM and 10uM with both SERS and UV absorptionspectroscopy. With UV absorption spectroscopy, we precisely estimate theconcentration as 2.1uM. We have shown that sample in PP tube can becontaminated due to leaching chemicals upon long term storage and suggestedSERS and UV-absorption spectroscopy as two quick and simple techniques todetect the contamination