3D ZnIn2S4 nanosheets decorated ZnCdS dodecahedral cages as multifunctional signal amplification matrix combined with electroactive/photoactive materials for dual mode electrochemical - photoelectrochemical detection of bovine hemoglobin.

The construction of dual mode sensor has gained tremendous attention due to its high accuracy and sensitivity compared with a single-response system. Herein, a novel dual mode sensing platform based on a 3-dimensional (3D) ZnCdS/ZnIn2S4 double-shelled dodecahedral cages (DSDCs) is fabricated as the electrochemical (EC) - photoelectrochemical (PEC) multifunctional signal amplification matrix for the highly selective detection of bovine hemoglobin (BHb). To achieve simple and fast detection of BHb, Au@Cu2O and SnO2/SnS2 are acted as EC - PEC signal indicators, respectively. More interestingly, the electroactive Au@Cu2O and photoactive SnO2/SnS2 are assembled on the 3D ZnCdS/ZnIn2S4 DSDCs, which could effectively increase the electron transfer process, consequently amplifying the readout of the dual mode responses. Besides, polydopamine (PDA) is used as a monomer for protein imprinting. Under the optimized conditions, the dual mode sensor exhibits a wide linear concentration range from 10-19 mg mL-1 to 10-1 mg mL-1 with a low detection limit 6.5 × 10-20 mg mL-1. Furthermore, the excellent selectivity, stability and acceptable reproducibility of the designed sensor will offer an alternation for the detection of other biomacromolecules in clinic diagnosis field.