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Background: The fabrication of sensors capable of achieving rapid, sensitive, and highly selective detection of target molecules in complex fluids is key to realizing their real-world applications. For example, there is an urgent need in drugged driving roadside screening scenarios to develop a method that can be used for rapid drug detection and that avoids interference from the matrix in the sample. How to minimize the interference of complex matrices in biofluids at the electrode interface is the key to improve the sensitivity of the sensor., Results: This work develops a facile and green method to prepare rough electrodes with a porous structure for constructing electrochemical aptamer-based (EAB) sensors for rapid, sensitive and accurate detection of Δ 9 -tetrahydrocannabinol (THC) in biofluids. The electroactive area of the rough electrode was 21 times of smooth electrode. And the antifouling performance of the rough electrode was much better than that of smooth electrode. Based on the unique advantages of the rough electrode, the developed EAB sensor achieves rapid nanomolar detection of THC in undiluted serum, undiluted urine and 50 % saliva with the detection limit of 5.0 nM, 10 nM and 10 nM, respectively. Moreover, our method possesses good reproducibility, accuracy and specificity., Significance: The porous structure can effectively reduce the non-specific adsorption and enhance the stability of the signal, while the larger active area can modify more aptamers, thus improving the sensitivity. The detection limits of the EAB sensor were lower than the cutoff concentration of THC in drugged driving and the measuring process was completed within 60 s after target addition, which makes the present sensors capable for real-world applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

To investigate the potential application of nitrocellulose membrane (NCM) in water treatment, this study examined the photolysis of p -nitrophenol, with NCM as the source of reactive oxygen species. Effects of solution pH, light conditions, and water dissolved substances on p -nitrophenol photolysis were investigated, and possible mechanisms were discussed. The results demonstrated that the quantum yield for hydroxyl radicals from the NCM was 1.30×10 -4 , which is approximately 1.86 times higher than that from TiO 2 . The photolysis rate of p -nitrophenol in the presence of NCM was 0.0055 min -1 , which is much higher than that in pure water (9.52×10 -4 min -1 ). This promotion was mainly caused by photo-induced generation of ·OH on NCM surface under light, in which UVA plays an important role in photolysis. The photolysis rate of p -nitrophenol increased with the increase of light intensity and membrane area. Acidic solution (pH=2.0) was preferred for the degradation of p -nitrophenol, with a photolysis rate of 0.0165 min -1 ; the corresponding degradation of p -nitrophenol exceeded 90% in 120 min. The effects of dissolved substances on photolysis were significantly different. NO 3 - promoted photolysis by generation of ·OH, and dissolved organic matter decreased photolysis through light attenuation. The intermediate products of gas chromatography-mass spectrometry analysis mainly included phenol, hydroquinone, malonic acid, and oxalic acid, and the possible photolysis pathway was given accordingly.