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Updated: Jul 14, 2026

Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
Cantilever-based sensor for the detection of different chromophore isomers
Rosangelly Flores-Perez1, Amit K Gupta, Rashid Bashir
1Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
Abstract:
We report the use of microcantilevers (MCs) for the detection of three retinoid isomers: 9-cis-retinal, 13-cis-retinal and all-trans-retinal. Detection of synthetic and natural retinoids in topical cosmetic products is important, and their presence can be used to predict reactions with the skin surface. In this study the MC surfaces were functionalized in order to promote the formation of covalent bonds with the chromophores. The lowest mass shift we detected with the functionalized MCs was 1.2 ppt, which is in the range needed by the cosmetics industry. Our results indicate that properly designed and functionalized microcantilevers can be used to construct economical, fast, and sensitive sensors for quality control in cosmetics.
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