T/AHEMA 24-2022 Active

Scope: This document specifies the terms and definitions, technical requirements, test methods, inspection rules, and markings related to surface-enhanced Raman scattering (SERS) substrates applied to water body environmental monitoring. This document is applicable to SERS substrates with gold, silver, and semiconductor metal oxides as the core sensitive units, primarily used for on-site rapid monitoring of pollutants such as dyes, organochlorine pesticides, organophosphorus pesticides, herbicides, polychlorinated biphenyls (PCBs), heavy metals, and Escherichia coli in surface and underground water bodies. Main technical content: 5. Technical requirements: - Working environment of the substrate: a) Environmental temperature: -10°C to 40°C. b) Environmental humidity: <90%. - Appearance requirements: The substrate must be solid, with a surface effective area of no less than 2 mm2, and free from obvious scratches, cracks, or other defects that may affect monitoring quality. It should have a regular shape and uniform size. - Functional requirements: 5.3.1 Enhancement factor: The SERS enhancement factor of the substrate should be greater than 103. 5.3.2 Signal uniformity: The relative standard deviation of the Raman characteristic vibration peak intensity should be less than 20%. 5.3.3 Cleanliness: For non-functionalized substrates, the maximum intensity of the baseline of the native Raman spectrum should not exceed 5000, and the Raman vibration peak intensity after baseline subtraction should not exceed 2000; for functionalized substrates, there is no need to evaluate their cleanliness. 5.3.4 Stability: During the validity period, the SERS enhancement factor of the substrate should not decrease by more than one order of magnitude. 6. Test methods: - Test conditions comply with the normal working conditions specified in 5.1. - Morphology and size: Visually inspect the morphology and regularity of the substrate, and test the surface effective area according to the meth