Glioma markers detection and assessment based on a photonic suspension array

Abstract

A new multiplex glioma marker immunoassay was developed based on a photonic suspension array. The micro-carriers of this array were silica colloidal crystal beads (SCCBs). As the code of the micro-carriers is the characteristic reflection peak originating from the stop-band of the colloid photonic crystal, they could effectively avoid photo-bleaching, the potential interference of encoding fluorescence with analyte-detection fluorescence and chemical instability. Meanwhile, the fluorescence background of the SCCBs is very low, because no dyes or materials with related fluorescence are included. The proposed suspension array was used for simultaneous multiplex detection of three glioma markers in one test tube by forming a sandwich immunocomplex on the SCCBs. The results showed that the three markers, Bcl-2 protein, cyclinD1 and p21, could be assayed in the ranges of 10–180 ng ml⁻¹, 0.1–13.5 ng ml⁻¹, 0.053–0.9 ng ml⁻¹, with limits of detection of 1 ng, 0.1 ng, 0.053 ng at 3σ, respectively. The proposed array has also shown storage stability and accuracy for sample detection. This technique provides a new strategy for low cost, automated, and simultaneous multiplex immunoassay.