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 WS 2 directly grown on an array of three-dimensional (3D) WO 3 nanohelixes (NHs) by sulfurization. Both the adsorption of biomolecules and the proliferation of cells are significantly promoted for the 3D WS 2 /WO 3 NH sensor compared to the control sensor with sulfurized WS 2 on 2D WO 3 film, leading to much enhanced sensitivity to dopamine. In addition, according to the in vitro test using PC12 cells, the 3D WS 2 /WO 3 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.