A novel facile method of fabricating disposable and highly reproducible surface-enhanced Raman spectroscopy (SERS) arrays using screen printing was explored. The screen printing ink containing silver nanoparticles was prepared and printed on supporting materials by a screen printing process to fabricate SERS arrays (6 × 10 printed spots) in large batches. The fabrication conditions, SERS performance and application of these arrays were systematically investigated, and a detection limit of 1.6 × 10(-13) M for rhodamine 6G could be achieved. Moreover, the screen printed SERS arrays exhibited high reproducibility and stability, the spot-to-spot SERS signals showed that the intensity variation was less than 10% and SERS performance could be maintained over 12 weeks. Portable high-throughput analysis of biological samples was accomplished using these disposable screen printed SERS arrays.

A novel facile method for on-site detection of substituted aromatic pollutants in water using thin layer chromatography (TLC) combined with surface-enhanced Raman spectroscopy (SERS) was explored. Various substituted aromatics in polluted water were separated by a convenient TLC protocol and then detected using a portable Raman spectrometer with the prepared silver colloids serving as SERS-active substrates. The effects of operating conditions on detection efficacy were evaluated, and the application of TLC-SERS to on-site detection of artificial and real-life samples of aromatics/polluted water was systematically investigated. It was shown that commercially available Si 60-F(254) TLC plates were suitable for separation and displayed low SERS background and good separation efficiency, 2 mM silver colloids, 20 mM NaCl (working as aggregating agent), 40 mW laser power, and 50 s intergration time were appropriate for the detection regime. Furthermore, qualitative and quantitative detection of most of substituted aromatic pollutants was found to be readily accomplished using the developed TLC-SERS technique, which compared well with GC-MS in terms of identification ability and detection accuracy, and a limit of detection (LOD) less than 0.2 ppm (even at ppb level for some analytes) could be achieved under optimal conditions. The results reveal that the presented convenient method could be used for the effective separation and detection of the substituted aromatic pollutants of water on site, thus reducing possible influences of sample transportation and contamination while shortening the overall analysis time for emergency and routine monitoring of the substituted aromatics/polluted water.

Hydrogen sulfide (H2 S) has emerged as an important gasotransmitter in diverse physiological processes, although many aspects of its roles remain unclear, partly owing to a lack of robust analytical methods. Herein we report a novel surface-enhanced Raman scattering (SERS) nanosensor, 4-acetamidobenzenesulfonyl azide-functionalized gold nanoparticles (AuNPs/4-AA), for detecting the endogenous H2 S in living cells. The detection is accomplished with SERS spectrum changes of AuNPs/4-AA resulting from the reaction of H2 S with 4-AA on AuNPs. The SERS nanosensor exhibits high selectivity toward H2 S. Furthermore, AuNPs/4-AA responds to H2 S within 1 min with a 0.1 μM level of sensitivity. In particular, our SERS method can be utilized to monitor the endogenous H2 S generated in living glioma cells, demonstrating its great promise in studies of pathophysiological pathways involving H2 S.

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Toxic organic pollutants in the aquatic environment cause severe threats to both humans and the global environment. Thus, the development of robust strategies for detection and removal of these organic pollutants is essential. For this purpose, a multifunctional and recyclable membrane by intercalating gold nanoparticles and graphitic carbon nitride into graphene oxide (GNPs/g-C 3 N 4 / GO) is fabricated. The membranes exhibit not only superior surface enhanced Raman scattering (SERS) activity attributed to high preconcentration ability to analytes through π-π and electrostatic interactions, but also excellent catalytic activity due to the enhanced electron-hole separation efficiency. These outstanding properties allow the membrane to be used for highly sensitive detection of rhodamine 6G with a limit of detection of 5.0 × 10 −14 m and self-cleaning by photocatalytic degradation of the adsorbed analytes into inorganic small molecules, thus achieving recyclable SERS application. Furthermore, the excellent SERS activity of the membrane is demonstrated by detection of 4-chlorophenol at less than nanomolar level and no significant SERS or catalytic activity loss was observed when reusability is tested. These results suggest that the GNPs/g-C 3 N 4 /GO membrane provides a new strategy for eliminating traditional, single-use SERS substrates, and expands practical SERS application to simultaneous detection and removal of environmental pollutants.