Porous Hydrogel Encapsulated Photonic Barcodes for Multiplex MicroRNA Quantification

The development of a highly sensitive platform for multiplex circulating microRNAs (miRNAs) detection is important for clinical diagnosis. Here, a new type of porous hydrogel encapsulated photonic crystal (PhC) barcodes is presented with integrated rolling circle amplification (RCA) strategy for multiplex miRNA quantification. As the surrounding porous hydrogel shells of the PhC barcodes are interconnected inverse opal structure with hydrophilic scaffolds, they can provide homogeneous water surrounding for the miRNA targets reaction and RCA. The encapsulated PhC cores of the barcodes can offer stable diffraction peaks for encoding different miRNAs and their RCAs during the detection. By integrating the advantages of PhC barcodes and RCA, it is demonstrated that the technology shows acceptable accuracy and detection reproducibility for the rapid quantification of low-abundance miRNAs, with the limits of detection of 20 fM. Thus, the proposed porous hydrogel encapsulated PhC barcodes provide a new platform for the multiplex quantification of low-abundance targets for practical applications.