Machine learning-enhanced drug testing for simultaneous morphine and methadone detection in urinary biofluids.

The simultaneous identification of drugs has considerable difficulties due to the intricate interplay of analytes and the interference present in biological matrices. In this study, we introduce an innovative electrochemical sensor that overcomes these hurdles, enabling the precise and simultaneous determination of morphine (MOR), methadone (MET), and uric acid (UA) in urine samples. The sensor harnesses the strategically adapted carbon nanotubes (CNT) modified with graphitic carbon nitride (g-C3N4) nanosheets to ensure exceptional precision and sensitivity for the targeted analytes. Through systematic optimization of pivotal parameters, we attained accurate and quantitative measurements of the analytes within intricate matrices employing the fast Fourier transform (FFT) voltammetry technique. The sensor's performance was validated using 17 training and 12 test solutions, employing the widely acclaimed machine learning method, partial least squares (PLS), for predictive modeling. The root mean square error of cross-validation (RMSECV) values for morphine, methadone, and uric acid were significantly low, measuring 0.1827 µM, 0.1951 µM, and 0.1584 µM, respectively, with corresponding root mean square error of prediction (RMSEP) values of 0.1925 µM, 0.2035 µM, and 0.1659 µM. These results showcased the robust resiliency and reliability of our predictive model. Our sensor's efficacy in real urine samples was demonstrated by the narrow range of relative standard deviation (RSD) values, ranging from 3.71 to 5.26%, and recovery percentages from 96 to 106%. This performance underscores the potential of the sensor for practical and clinical applications, offering precise measurements even in complex and variable biological matrices. The successful integration of g-C3N4-CNT nanocomposites and the robust PLS method has driven the evolution of sophisticated electrochemical sensors, initiating a transformative era in drug analysis.

In situ preparation of g-C3N4 nanosheet/FeOCl: Achievement and promoted photocatalytic nitrogen fixation activity.

Climate change, global warming, and population growth have led researchers to use eco-sociable procedures for the N2 reduction reaction. It has discovered that N2 molecule can be transformed into NH3 in ambient circumstances with nanocomposites upon visible irradiation. In this research paper, a new visible-light-driven photocatalyst was constructed, with various weight percents of FeOCl particles (10, 20, 30, and 40%) that have adhered on NS-CN. Subsequently, multiple features of the nanocomposites were assayed in detail. The results illustrated that the NS-CN/FeOCl (20%) system has remarkable photoactivity in the NH4+ production reaction in comparison with the NS-CN and CN, which showed 2.5 and 8.6 higher activity, respectively. The durability of NS-CN/FeOCl (20%) system, as a substantial factor, was assayed for 5 recycles. Moreover, the effect of electron quenchers, pH of media, and solvent was studied. At last, a feasible Z-scheme mechanism for the remarkable improvement of N2 fixation efficiency was offered.

Fabrication of novel magnetically separable nanocomposites using graphitic carbon nitride, silver phosphate and silver chloride and their applications in photocatalytic removal of different pollutants using visible-light irradiation.

In the present study, g-C3N4/Fe3O4/Ag3PO4/AgCl nanocomposites endowed with efficient photocatalytic activity under visible-light irradiation have been successfully prepared by a facile ultrasonic-irradiation method. The prepared samples were characterized by XRD, EDX, AAS, SEM, TEM, UV-vis DRS, FT-IR, TG, PL, and VSM techniques. Rhodamine B, methyl orange, fuchsine, and phenol were selected as pollutants to evaluate photocatalytic activity of the as-prepared samples. Among the samples, the g-C3N4/Fe3O4/Ag3PO4/AgCl (30%) nanocomposite displayed the highest photocatalytic activity. It was found that activity of this nanocomposite in degradation of rhodamine B is nearly 22, 6, and 7.5-times higher than those of the g-C3N4, g-C3N4/Fe3O4/Ag3PO4 (20%), and g-C3N4/Fe3O4/AgCl (30%) samples, respectively. The significant amount of saturation magnetization (8.78emug(-1)) for this nanocomposite indicated that the photocatalyst can be easily separated from the treated solution using a magnetic field. According to the trapping experiments, it was found that holes are main active species, driving the degradation reaction. This work suggests that the quaternary nanocomposite is promising photocatalyst for degradation of organic pollutants under visible-light illumination.

Magnetically separable ternary g-C3N4/Fe3O4/BiOI nanocomposites: Novel visible-light-driven photocatalysts based on graphitic carbon nitride.

The present work demonstrates preparation of magnetically separable ternary g-C3N4/Fe3O4/BiOI nanocomposites as novel visible-light-driven photocatalysts. The resultant samples were characterized using XRD, EDX, SEM, TEM, UV-Vis DRS, FT-IR, PL, BET, and VSM techniques. The results revealed that weight percent of BiOI has considerable effect on photodegradation of rhodamine B under visible-light irradiation. Among the prepared samples, the g-C3N4/Fe3O4/BiOI (20%) nanocomposite has the best photocatalytic activity. The activity of this nanocomposite is about 10, 22, and 21-fold higher than that of the g-C3N4 sample in degradation of rhodamine B, methylene blue, and methyl orange under the visible-light irradiation. The excellent activity of the magnetic nanocomposite was attributed to more harvesting of the visible-light irradiation and efficiently separation of the electron-hole pairs. More importantly, the nanocomposite was magnetically separated after five successive cycles.