Three-Dimensional Tungsten Disulfide Raman Biosensor for Dopamine Detection

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) are promising materials for detection of biomolecules due to their large surface-to-volume ratio. However, their poor response to the cellular environment hinders the realization of high-performance 2D TMDC sensors. Here, we present a hierarchical Raman scattering sensor consisting of the WS₂ directly grown on an array of three-dimensional (3D) WO₃ nanohelixes (NHs) by sulfurization. Both the adsorption of biomolecules and the proliferation of cells are significantly promoted for the 3D WS₂/WO₃ NH sensor compared to the control sensor with sulfurized WS₂ on 2D WO₃ film, leading to much enhanced sensitivity to dopamine. In addition, according to the in vitro test using PC12 cells, the 3D WS₂/WO₃ NH sensor shows a significant increase in hydrophobicity and Raman frequency shift, indicating that both the attachment of cells and the detection of biomolecules are improved.