Flexible SERS wearable sensor based on nanocomposite hydrogel for detection of metabolites and pH in sweat

Flexible Wearable Plasmonic Paper-Based Microfluidics with Expandable Channel and Adjustable Flow Rate for Portable Surface-Enhanced Raman Scattering Sweat Sensing

“…11−13 However, colorimetric and fluorescence techniques exhibit significant limitations in long-term continuous monitoring, 14,15 while electrochemical techniques not only require intricate electrode design and complex circuitry 12,16 but also exhibit less composition information and poor anti-interference ability. 17,18 On the contrary, SERS can provide plentiful compositional information by virtue of the inherent molecular fingerprints of analytes and is basically insusceptible to external factors. 19,20 However, its application in human sensing has been less studied.…”

“…38,39 While abnormal pH value of sweat is closely related to metabolic alkalosis and cystic fibrosis. 17,40 Currently, only a few studies have reported the implementation of wearable in situ sweat SERS sensing using portable Raman spectroscopy techniques. 23,29,41 Here, we designed a flexible wearable plasmonic paper-based microfluidic (FWPPM) device for the noninvasive detection of sweat.…”

Wearable Surface-Enhanced Raman Spectroscopy Sensor Using Inverted Bimetallic Nanopyramids for Biosensing and Sweat Monitoring

“…18,19 Wang et al investigated multiplex detection of three different hepatocellular carcinoma-related microRNA biomarkers using fractal Au nanotags. 20 Further, SERS-based wearable biosensors have attracted enormous attention because of their sensitive, rapid response and noninvasive molecular fingerprint analysis for healthcare monitoring. Recently Wang et.…”

“…However, their complex fabrication process and low selectivity in simultaneously testing multiple biomarkers are some major challenges. − Surface-enhanced Raman scattering (SERS) spectroscopy-based detection is considered to be an excellent label-free analytical method for trace molecules and protein structural characterization and quantification, with sensitivity down to a single molecule. , As per previous reports, the use of the SERS technique significantly improves the applicability of Raman spectroscopy in hematological analysis, such as the detection of anemia, leukemia, nanotoxicity in cells, glucose level monitoring, and cancer screening. − Wearable SERS biosensors hold considerable promise for multiplexed chemical analysis of bioanalytes present in biofluids. Several studies have demonstrated the high sensitivity and specificity of SERS-based sensors. , Wang et al investigated multiplex detection of three different hepatocellular carcinoma-related microRNA biomarkers using fractal Au nanotags . Further, SERS-based wearable biosensors have attracted enormous attention because of their sensitive, rapid response and noninvasive molecular fingerprint analysis for healthcare monitoring.…”

“…Recently Wang et. al reported a flexible sensor based on a sulfonated cellulose silver nanocomposite hydrogel for the analysis of metabolites in sweat, but the performance of the sensor degrades over time due to the instability of silver nanoparticles in the air . Previously reported wearable SERS sensors can provide sensitive detection of various biomarkers (e.g., lactic acid, urea, creatine, and nicotine) in sweat. − .…”