title: Selective determination of homocysteine levels in human plasma using a silver nanoparticle-based colorimetric assay.
abstract: The first use of silver nanoparticles (AgNPs) for the rapid, simple, and selective determination of homocysteine (Hcy) levels in human plasma was studied. Hcy and five other amino acids, including cysteine (Cys), could be distinguished by their different aggregation kinetics, which caused a change in the visible color and a shift in the UV-vis absorption spectra. The difference in the cross-linking (aggregation) rate between Hcy and Cys was used as the basis for developing a selective probe for Hcy and allowed the detection of Hcy in the linear range of 2-12 μM (R(2)=0.9936). The limits of detection and quantification were found to be 0.5 μM and 1.7 μM, respectively. To investigate its selectivity and potential applicability, this AgNP-based method was successfully applied for the determination of Hcy levels in actual biological (human plasma) samples, where the determined levels of Hcy were within the error range of the measured level using the traditional chemiluminescence microparticle immunoassay (CMIA). Thus, the use of AgNPs is a feasible and potentially reliable method for the determination of Hcy levels in biological samples.
authors: Program in Biotechnology, Faculty of Science, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand.
authors: Wiphawee
authors: W
authors: Leesutthiphonchai
authors: Wijitar
authors: W
authors: Dungchai
authors: Weena
authors: W
authors: Siangproh
authors: Nattaya
authors: N
authors: Ngamrojnavanich
authors: Orawon
authors: O
authors: Chailapakul
mesh_terms: D001774:Blood Chemical Analysis / Q000379:methods*; D003124:Colorimetry / Q000379:methods*; D003545:Cysteine / Q000737:chemistry; D006710:Homocysteine / Q000097:blood* / Q000737:chemistry; D006801:Humans; D007700:Kinetics; D053768:Metal Nanoparticles / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013997:Time Factors
chemical_list: D006710:Homocysteine; D012834:Silver; D003545:Cysteine