Fluorescent CdSe/ZnS quantum dots incorporated poly (styrene-co-maleic anhydride) nanospheres for high-sensitive C-reaction protein detection

Abstract

We have reported the formation of fluorescent CdSe/ZnS quantum dots (QDs) incorporated poly (styrene-co-maleic anhydride) spheres in nanoscale range with a simple emulsification solvent evaporation strategy. The influence parameters on the size and internal structure of the composite nanospheres, such as copolmer/QDs mass ratio and volume ratio of water/chloroform were systematically investigated. Our obtained QDs incorporated polymer nanospheres were suitable for some immunoassays which strongly required nano-sized fluorescent labels, such as lateral flow immunoassays (LFIAs), in which “easily flowing chromatographically along the strip” was needed. Finally, carboxyl-functionalized nanospheres were used as fluorescent tags and imported into LFIA system to on-site high-sensitively assess the level of C-reaction protein (CRP). Within the range of high-sensitive detection (from 0.04 to 10.0 mg/L), nanosphere-based LFIA sensor exhibited linear detection of CRP (R2 = 0.9995) and a detection limit of 0.04 mg/L, which may be useful to improve the risk assessment of cardiovascular disease.