Griess reaction-based paper strip for colorimetric/fluorescent/SERS triple sensing of nitrite

Nitric Oxide Detection Using Electrochemical Third‐generation Biosensors – Based on Heme Proteins and Porphyrins

“…NO research has been increasing in the last years and this boost demands the development of analytical techniques capable of precisely and accurately quantify NO levels and rates of production. Moreover, several methodologies have been developed to measure NO: (i) indirect detection, quantifying cyclic guanosine monophosphate ( c GMP), a biologically active second messenger , or by the NO oxidation products, using fluorescent probes or the Griess reaction ; (ii) direct detection, exploring different properties of NO, such as its radical nature, using electron paramagnetic resonance spectroscopy , its reactivity towards some metalloproteins (e. g., reaction with reduced hemoglobin and methemoglobin formation) or its ability to react with ozone to produce light, using chemiluminescence detection . While most of these approaches display high sensitivity and selectivity for NO, all present specific limitations, with one main issue being the spatial resolution in vivo , which cannot be obtained with a “bulk” method.…”

The synthesis of a chemically reactive and polymeric luminescent gel

“…In the recent past, different nanomaterials, including carbon dots, [76][77][78][79] dye-doped silica nanoparticles, 60 polyethyleneiminecapped CdS quantum dots, 75 4-aminothiophenol modified gold nanorods, 80 graphite-like carbon nitride nanomaterial, 81 ophenylenediamine-BODIPY probe, 82 inorganic complexes like iron and manganese pyridoxal-based complexes, 83 polymeric matrices, [84][85] metal-organic frameworks, 86 functionalized gold and silver nanoparticles etc. [87][88][89][90][91] were developed for colorimetric and fluorescence-based detection of NO2ions. However, over the time, the aggregation of nanomaterials in the solution phase is likely to lead to ambiguity in the measurement of the respective optical signals at practically relevant diverse settings.…”

Surface‐enhanced Raman spectroscopy for on‐site analysis: A review of recent developments

“…This substrate was applied to on-site detection of nitrite in human urine and meat products, and the LOD for nitrite by SERS was 0.8 nM, which is superior to colorimetric and fluorescence methods. [98] It was proved that the gold layer was deposited onto a thin polymer film T A B L E 1 Summary of technical information on some commercial portable Raman spectrometers Based on the advantages of self-adhesive analytes and high sensitivity, combined with a portable Raman spectrometer, this flexible substrate has been demonstrated to achieve outdoor (on-site) rapid analysis. [70] 3.2 | Three-dimensional (3D) flexible SERS substrate…”