#Peripheriam circuli portable#

Thus, an intrinsically connected SERS substrate with fine structural entirety is chosen and independently embedded in the well-defined vessel of microfluidics for in situ and continuous SERS sensing. In our microfluidic system, the used SERS substrate does not need to play the role of sweat sampling. 1, the polydimethylsiloxane (PDMS) microfluidics achieves sweat collection with programmable flowing routing and eliminates contamination and evaporation.

#Peripheriam circuli portable#

In this paper, we propose a wearable plasmonic sensor, bridging the gap between wearable sweat microfluidics with the SERS signal output technique using a portable Raman analyzer. The conventional heavy Raman instrument limits wearable SERS analysis in standardized laboratory settings, which dramatically weakens the practicality and applicable circumstances. Another significant issue of the previously-proposed wearable sweat SERS platforms is the readout system. Additionally, dynamical sweat transporting enabled by microfluidics can minimize the mixing and carry-over effect of the new and old sweat 40, ensuring the SERS analysis is performed in a refreshable and high temporal resolution manner. By comparison, microfluidics can spatially control the localization of SERS substrates, and the SERS substrates can be flexibly chosen and configured. However, the cost is that these permeable SERS substrates are usually structurally unstable and vulnerable to epidermal deformation when touching the skin. However, these non-microfluidic sweat systems rely on sweat-permeable (porous) SERS substrates that allow sweat to wick and occupy the hotspots. At the present, only few wearable SERS sweat sensors have been demonstrated 35, 38, 39. Flexible plasmonic devices by integration of SERS with wearable techniques have attracted tremendous attention for diverse wearable biomedical applications 32, 33, 34, 35, 36, 37. SERS is a commonly used analytical technique capable of achieving high enhancement of Raman signals through localized plasmon-enhanced excitation and scattering 29, 30, 31. Continuous innovations towards developing new signal reading techniques are necessary to furnish our options for designing wearable sweat sensors. Each sensing strategy has its own merits and shortcomings (Supplementary Table 1). Electrochemical techniques are featured with high sensitivity and selectivity, where the electrodes can also be flexibly designed into different shapes and sizes. Electrochemical sensors are widely adopted for sweat analysis by transducing target contents into currents or potential signals at miniature and specific electrode surfaces 23, 24, 25, 26, 27, 28. Wearable colorimetric 17, 18, 19 and fluorescent 20, 21, 22 sweat sensors have offered visual sensing access via observation of color/absorbance/fluorescence depth related to the chromogenic/luminous reaction between indicator and analytes. Remarkable progress has been made in these wearable sweat sensors by combining molecular recognition methods, micro-nano device manufactures, integrated hardware/software systems, and various analytical techniques 14, 15, 16. More specifically, wearable sweat sensors that enable cognition of molecular-level signatures related to physiological information in epidermally available sweat are regarded as an extremely competitive device 10, 11, 12, 13. This study integrates epidermal microfluidics with portable SERS molecular recognition, presenting a controllable, handy, and dynamical biofluid sensing system for personalized medicine.įlexible smart electronics have revolutionized our cognition, methodology, and techniques in electronic skin, human-machine interaction, personalized healthcare 1, 2, 3, 4, 5, 6, 7, 8, 9. We use a portable and customized Raman analyzer with a friendly human-machine interface for portable recognition of the spectroscopic signatures of sweat biomarkers. Compared to conventional wearable SERS platforms with the risk of mixed effect between new and old sweat, the microfluidic SERS system allows sweat administration in a controllable and high temporal-resolution fashion, providing refreshable SERS analysis. A miniature, thin plasmonic metasurface with homogeneous mushroom-shaped hot spots and high surface-enhanced Raman scattering (SERS) activity is designed and integrated into a microfluidics platform. Here, we demonstrate a wearable microfluidic nanoplasmonic sensor capable of refreshable and portable recognition fingerprint information of targeted biomarkers including urea, lactate, and pH in sweat. Wearable sweat sensors with various sensing systems can provide noninvasive medical diagnostics and healthcare monitoring.