IR-Driven Multisignal Conditioning for Multiplex Detection: Thermal-Responsive Triple DNA-Mediated Reconfigurable Photoelectrochemical/Photothermal Dual-Mode Strategy.

Superior to traditional multiplex photoelectrochemical (PEC) sensors, integrated multitarget assay on a single reconstructive electrode interface is promising in real-time detection through eliminating the need of specialized instrumentation and cumbersome interfacial modifications. Current interface reconstruction approaches including pH modulation and bioenzyme cleavage involve biohazardous and time-consuming operations, which cannot meet the demand for rapid, eco-friendly, and portable detection, which are detrimental to the development of multiplex PEC sensors toward portability. Herein, we report a pioneer work on IR-driven "four-to-one" multisignal conditioning to facile reconfigure electrode interface for multitarget detection via photoelectrochemical/photothermal dual mode. The copper sulfide quantum dot (CuS QD) with excellent photoelectrochemical properties and a photothermal effect is first labeled on DNA S2. Once the CuS QD-S2 complementarily pairs with the DNA S3 on the photocathode surface, thermal-responsive triple DNA is formed, and the photocurrent and photothermal dual-mode signals for one target assay are produced. Upon the dissociation of the triple DNA by IR irradiation, the electrode interface is reconfigured for the self-calibrating dual-mode detection of another target. The feasibility of the IR-driven multisignal conditioning sensor is confirmed by detecting coexistent antibiotics kanamycin (KANA) and neomycin (NEO) in complex real samples. The low-loss interface reconfiguration and rapid "four-to-one" multisignal modulation highlight a broad prospect for self-calibrating multiplex assay in the fields of environment, medicine, and food safety.