title: Spectrophotometric determination of L-cysteine by using polyvinylpyrrolidone-stabilized silver nanoparticles in the presence of barium ions.
abstract: In this article a simple and selective colorimetric probe for cysteine determination using silver nano particles (AgNPS) is described. The determination process was based upon the surface plasmon resonance properties of polyvinylpyrrolidone-stabilized AgNPS. Interaction of AgNPS with cysteine molecules in the presence of barium ions induced a red shift in the surface plasmon resonance (SPR) maximum of AgNPs, as a result of nanoparticle aggregation. Consequently, yellow color of AgNP solution was changed to pink. The linear range for the determination of cysteine was 3.2-8.2 μM (R=0.9965) with a limit of detection equal to 2.8 μM (3σ). The proposed method was successfully applied to the determination of cysteine in human plasma samples. Acceptable recovery results of the spiked samples confirmed the validity of the proposed method.
authors.affiliation: Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8-8349, Iran. Electronic address: F-Bamdad@araku.ac.ir.
authors.forename: Farzad
authors.initials: F
authors.lastname: Bamdad
authors.affiliation: Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8-8349, Iran.
authors.forename: Fateme
authors.initials: F
authors.lastname: Khorram
authors.affiliation: Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8-8349, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Samet
authors.affiliation: Department of Biology, Faculty of Science, Payame Noor University (PNU), PO Box 19395-3697, Iran.
authors.forename: Kourosh
authors.initials: K
authors.lastname: Bamdad
authors.affiliation: Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8-8349, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Sangi
authors.affiliation: Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8-8349, Iran.
authors.forename: Fateme
authors.initials: F
authors.lastname: Allahbakhshi
mesh_terms: D001464:Barium / Q000737:chemistry*; D003545:Cysteine / Q000032:analysis / Q000097:blood*; D006801:Humans; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011205:Povidone / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013053:Spectrophotometry; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D001464:Barium; D012834:Silver; D011205:Povidone; D003545:Cysteine
keywords: Aggregation; Cysteine; Human plasma; Silver nanoparticles; Surface plasmon