Sensitive and selective detection of glutathione based on resonance light scattering using sensitive gold nanoparticles as colorimetric probes

Abstract

In this paper, we reported the development of a highly sensitive and selective resonance light scattering (RLS) technique for glutathione using gold nanoparticle probes. The assay relies upon the distance-dependent optical properties of gold nanoparticles, the self-assembly of glutathione on gold nanoparticles, and the interaction of a 2 : 1 glutathione-Cu(2+) complex. In the presence of Cu(2+), glutathione could rapidly induce the aggregation of gold nanoparticles, thereby resulting in greatly enhanced RLS intensity and red-to-blue (or purple) color change. The concentration of glutathione can be determined by the naked eye or a fluorescence spectrometer. Under the optical conditions, the detection of glutathione can be finished within 20 min, and the detection limit of 10 nM can be reached. The concentration range of the probe is 40-280 nM. The proposed method holds a specific selectivity toward glutathione and it is applied to the detection of glutathione in human serum with satisfactory results. In addition, the assay shows great potential application for disease-associated biomarkers, and it will meet the great demand for amino acid determination in fields such as food processing, biochemistry, pharmaceutical, and clinical analysis.

Comparative study of alkylthiols and alkylamines for the phase transfer of gold nanoparticles from an aqueous phase to n-hexane

“…S1b), implying the potential aggregation or coagulation of Au-NPs in the n-hexane phase after the ODT-assisted phase transfer. Similar color changes from red to purple to blue were observed during the coalescence of Au-NPs [35][36][37].…”

Strategies for enhancing the sensitivity of plasmonic nanosensors

“…Thus, the detection of resonance light scattering (RLS) could be a very sensitive approach for aggregation-based plasmonic L. Guo et al nanosensors. In fact, this detection mechanism has been extensively used for the sensitive assay of DNA [228][229][230], proteins [231][232][233], small molecules [234][235][236][237] and metal ions [238][239][240]. The hyper-Rayleigh scattering (HRS) technique can determine the microscopic nonlinear optical properties of species in solution.…”

Chitosan-capped gold nanoparticles for selective and colorimetric sensing of heparin

“…The light scattering signals can be easily detected by synchronously scanning both the excitation and emission monochromators with a conventional spectrofluorometer (Pasternack et al 1993; Pasternack et al 1995; Brar and Verma 2011; Ling et al 2009; Ling et al 2007). To date, RLS has been applied to the study and determination of nucleic acids (Huang et al 1997), adenine (Xu et al 2012), amino acid (Chen et al 2012), and screening of anticancer drugs (Chen et al 2010; Chen et al 2011). With the development of nanoscience and nanotechnology, gold nanoparticles (AuNPs) based on RLS methods have been attracting enormous attention in biomolecule detection, since the light scattering ability of AuNPs is about four orders of magnitude stronger than that of a fluorescent dye (Li and Li 2009).…”