Label-Free, Real-Time Multiplexed DNA Detection Using Fluorescent Conjugated Polymers

A label-free, multiplexed DNA assay using fluorescent conjugated polymers as a detection probe to illustrate hybridization on metallic striped nanorods is demonstrated. Different DNA capture probes were encoded by the different reflectivities of Au and Ag stripe patterns. Successful DNA hybridization induced an optically detectable conformational change in conjugated polythiophene derivatives from forming single-stranded DNA-polymer complexes to forming double-stranded DNA-polymer ones. The results show attomole detection sensitivity and single-mutation specificity comparable to those of single-element assays but with much improved throughput.