PubMed Health⌕ Search

Biomedical subjects

Vinod Topiwala

Publications and source records attributed to Vinod Topiwala.

2 recordsLinked to original sources

Quantitative determination of formaldehyde in cosmetics using a combined solid-phase microextraction-isotope dilution mass spectrometry method.

Solid-phase microextraction (SPME) in conjunction with isotope dilution mass spectrometry (ID-MS) was employed for the analysis of formaldehyde in cosmetic products. The formaldehyde is derivatized in situ with pentafluorophenyl hydrazine. The formed hydrazone is adsorbed over a poly(dimethylsiloxane)-divinylbenzene-coated fiber and analyzed using gas chromatography-mass spectrometry. The adsorption-time profiles and salting effect were studied. The quantitation was performed by using a stable isotope labeled analogue as an internal standard. The precision, recovery and detection limits were determined with spiked samples. The relative standard deviations from different spiked cosmetic samples were all less than 10% and the recoveries were between 89.00 and 101.23%. The limit of detection was of 0.39 microg/l. Compared with other techniques, the study shown here provides a simple, fast and reliable method for the analysis of formaldehyde in cosmetic products.

Calibration↗

Quantitative determination of formaldehyde in cosmetics using combined headspace-solid-phase microextraction-gas chromatography.

The objective of this research was the application of headspace (HS)-solid-phase microextraction (SPME) for the quantitation of formaldehyde present in raw materials and cosmetic formulations. The formaldehyde was derivatized in situ first with pentafluorophenylhydrazine (PFPH), to form a derivative hydrazone. The formed hydrozone was adsorbed on a SPME fiber during headspace extraction under controlled conditions (time, temperature, volume, etc.). After the adsorption step, the SPME fiber was directly transferred into the gas chromatography (GC) injection port in which the analytes were thermally desorbed. Deuterated acetone was used as an internal standard (IS) in order to quantitate the formaldehyde content. For the experiment, a gas chromatograph equipped with a flame ionization detector (GC/FID) was employed. A gas chromatograph/mass spectrometer (GC/MS) was used for the qualitative confirmation of results in this work.

Chromatography, Gas↗