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Contact lenses have become a popular health‐monitoring wearable device due to their direct contact with the eyes. By integrating biosensors into contact lenses, real‐time and noninvasive diagnoses of various diseases can be realized. However, current contact lens sensors often require complex electronics, which may obstruct the user's vision or even damage the cornea. Moreover, most of the reported contact lens sensors can only detect one analyte. Therefore, an optical‐based dual‐functional smart contact lens sensor has been introduced to monitor intraocular pressure (IOP) and detect matrix metalloproteinase‐9 (MMP‐9), both of which are key biomarkers in many eye‐related diseases such as glaucoma. Specifically, the elevated IOP is continuously monitored by applying an antiopal structure through color changes, without any complex electronics. Together with the peptide modified gold nanobowls (AuNBs) surface‐enhanced Raman scattering (SERS) substrate, the quantitative analysis of MMP‐9 at a low nanomolar range is achieved in real tear samples. The dual‐sensing functions are thus demonstrated, providing a convenient, noninvasive, and potentially multifunctional sensing platform for monitoring health and diagnostic biomarkers in human tears. [ABSTRACT FROM AUTHOR]

Facile, rapid, and sensitive detection of pathogens is very crucial to control pathogen infection at its early stage. In this work, an ultrasensitive surface-enhanced Raman scattering (SERS) determination of ocular bacterial pathogens on vertically aligned gold nanowires (v-AuNWs) was proposed. The v-AuNWs substrate for the optimal SERS enhancement was obtained via optimizations of three experimental conditions, including the size and the spacing distances of seed nanoparticles, and the length of v-AuNWs, which was capable of non-labeled molecular detection and quantification, as well as bacterial analysis in clinical fluids. Furthermore, a high bacterial enrichment efficiency of up to 67% has been achieved by using a herringbone microchannel on the v-AuNWs substrate. As a result, the most common ocular bacterial pathogens, S. aureus, E. coli, P. aeruginosa, and S. epidermidis , have been discriminated on the v-AuNWs SERS platform facilitated by the partial least-squares discriminant analysis (PLS-DA) with an accuracy of 97.5%. This fast, non-labeled, and accurate bacterial sensing platform offers new possibilities for screening and control of microbial infection, especially in remote areas. [Display omitted] • Label-free SERS detection for ocular bacterial pathogens without culturing. • Vertically aligned gold nanowires (v-AuNWs) as the SERS substrate. • Bacterial classification by partial least-squares discriminant analysis method. • Spiked tears measured in a microfluidics channel with herringbone structures. [ABSTRACT FROM AUTHOR]