Gas-sensing applications commonly use nanomaterials (NMs) because of their unique physicochemical properties, including a high surface-to-volume ratio, enormous number of active sites, controllable morphology, and potential for miniaturisation.

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N 6 -methyladenine (m 6 A), one of the most common chemical modifications of eukaryotic RNA, participates in many important biological processes. An effective strategy for the quantitative determination of m 6 A is of great significance. Herein, we used methylated microRNA-21 (miRNA21) as the model target to propose a simple and sensitive electrogenerated chemiluminescence (ECL) biosensing platform to detect a specific m 6 A RNA sequence. This strategy is based on the fact that the anti-m 6 A-antibody can specifically recognize and bind to the m 6 A site in the RNA sequence, resulting in a quenching effect between Ru(bpy) 3 2+ -functionalized metal−organic frameworks and ferrocene. Luminescent metal−organic frameworks (Ru@MOFs) not only act as ECL indicators but also serve as nanoreactors for the relative ECL reactions owing to their porous or multichannel structure, which overcomes the fact that Ru(bpy) 3 2+ is easily released when used for aqueous-phase detection, thus enhancing the ECL efficiency. Moreover, the ECL method has fewer modification steps and uses only one antibody to recognize the target RNA sequence, which simplifies the operation process and reduces the detection time, presenting a wide linear range (0.001−10 nM) for m 6 A RNA determination with a low detection limit (0.0003 nM). Additionally, this developed strategy was validated for m 6 A RNA detection in human serum. Thus, the ECL biosensing method provides a new method for m 6 A RNA determination that is simple, highly specific, and sensitive. N 6 -Methyladenosine (m 6 A) has been identified as one of

Surface enhanced Raman scattering (SERS) has great potential in the early diagnosis of diseases by detecting the changes of volatile biomarkers in exhaled breath, because of its high sensitivity, rich chemical molecular fingerprint information, and immunity to humidity. However, two factors limit the application of SERS: 1) specific enrichment of trace target molecules in SERS hotspots; and 2) stability and reproducibility of SERS signals in multiinterference environments. In order to accurately detect biomarkers in the complex exhaled breath and to eliminate the interference of other components, hollow ZIF-8 wrapped on the gold superparticle with a yolk-shell structure is proposed as a SERS substrate. Similar to the solid ZIF layer, the hollow ZIF-8 layer is also enriched with gas molecules, and the enriched molecules reacts with functional molecules on the surface of the superparticle, generating a strong response signal. The difference is that the hollow ZIF layer can effectively exclude interfering molecules that are not bound to the modified molecules, and the detection limit is 5 times lower than the detection limit of core-shell structure substances. A mask-type sensor is prepared, and the obtained spectra are modeled by PC-LDA to determine the probability of illness in the actual population.

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The diffusion of target analytes is a determining factor for the sensitivity of a given gas sensor. Surface adsorption results in a low‐concentration region near the sensor surface, producing a concentration gradient perpendicular to the surface, and drives a net flux of molecules toward solid reactive reagents on the sensor surface, that is, vertical diffusion. Here, organic semiconductor supramolecules were patterned into micromeshed arrays to integrate vertical and horizontal diffusion pathways. When used as a gas sensor, these arrays have an order of magnitude higher sensitivity than traditional film‐based sensors. The sensor sensitivity ramp down with the increase in coverage density of reactive reagents, yielding two linear regions demarcated by 0.3 coverage, which are identified by the experimental results and simulations. The universal nature of template‐assisted patterning allows adjustments in the composition, size, and shape of the constituent material, including nanofibers, nanoparticles, and molecules, and thus serves to improve the sensitivity of gas sensors for detecting various volatile organic compounds.

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