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In this work, a photocatalytic process was used for removing metformin as a widely prescribed drug to reduce blood sugar in type 2 diabetes. Photocatalytic processes are one of the most common oxidation processes in degrading organic compounds. This study aimed to investigate the efficiency of Fe3+doped TiO2nanoparticles in degrading metformin in synthetic wastewater. Therefore, in the first step, Fe3+doped TiO2nanoparticles were synthesized by the sol–gel method and characterized using X-ray diffraction, energy-dispersive X-ray spectrometry, scanning electron microscopy, and pH(PZC) techniques. Then, the effects of parameters, such as the initial concentration of metformin (10–45 mg/L), catalyst dose (25–75 mg/L), pH (3–11), and time (30–150 min), were studied on the photocatalytic degradation of metformin. Results showed that by increasing the experimental parameters, including pH, catalyst dose, and contact time, the nanoparticle removal efficiency increased. Overall, these findings indicated that under optimum conditions, including pH = 11, nanoparticle dose of 75 mg/L, and contact time of 150 min, photocatalytic degradation can remove 93.8% of metformin with an initial concentration of 35 mg/L. Moreover, Fe3+doped TiO2nanoparticles with UV light (as a photocatalytic treatment system) have good efficiency in degrading metformin.

Research on the solubility of n‐propanol in different solvents is important because of the wide applications of n‐propanol in cosmetics, cleaning, printing, coatings, and chemical industries. The goal of this research was to investigate the structural or empirical properties of different solvents on the Ostwald solubility coefficient of n‐propanol. In this research, two different approaches, that is, linear solvation energy relationship (LSER) and quantitative structure–property relationship (QSPR), have been used to predict and descript the gas‐solvent partition coefficient of n‐propanol, as its solubility index, in 36 different solvents. In the suggested LSER model, the role of solvent–solute interactions on the solubility of n‐propanol as a physicochemical property can be investigated. In addition to structural features, which were used in the QSPR model, the interpretation of the LSER model showed that the donor number of solvents, modified polarity scale of solvents, and entropy of solvation are three important parameters in the Ostwald solubility coefficient of n‐propanol. For the first time, two QSPR and LSER models were suggested to predict and interpret the Ostwald solubility of 1‐pronanol, as solute, in different solvents using structural features and empirical scales of solvents. Very good statistical performance were obtained for both models. Results of LSER model showed that the donor number of solvents, modified polarity scale of solvents, and entropy of solvation are three important parameters in the Ostwald solubility coefficient of 1‐propanol.

In this study, Fe@Fe2O3nanowires were applied in combination with electro Fenton (EF) process to decompose of carbamazepine (CBZ) drug in an electrochemical reactor using a graphite rod cathode and Ti/PbO2anode. Response surface methodology (RSM) based on central composite design was used to optimize various parameters such as pH, current, FeSO4·7H2O, drug and Fe@Fe2O3concentrations, and reaction time. The results of RSM showed a good statistical relationship between experimental values of CBZ removal and their predicted values using the suggested multi-parameter model. The efficacy of CBZ removal significantly enhanced with increasing density, Fe@Fe2O3nanowire dose, and reaction time, while it was reduced with increasing pH, FeSO4·7H2O concentration, and initial concentration of the drug. The results on a percentage of contribution and the F-value (PC% = 42.99 and F = 346.4003) showed that Fe@Fe2O3dose plays an important role in increasing the efficiency of the electro Fenton process. RSM results also revealed that EF process effectively removed 88.55% of CBZ and 65% of total organic carbon from aqueous solutions under optimum conditions; that is pH = 4, current = 0.18 A (current density = 5.14 mA cm–2), FeSO4·7H2O concentration = 3.87 mg L–1, CBZ concentration = 7.49 mg L–1, Fe@Fe2O3dose = 1,050 mg L–1, and reaction time = 50 min. The utilized multi-parameter optimization approach revealed the presence of interactions between pH with FeSO4·7H2O concentration and pH with reaction time. As a conclusion EF process catalyzed by Fe@Fe2O3nanowire can be used for the removal of pharmaceutical compounds such as CBZ from aqueous solutions.

This paper describes the synthesis of some new β-lactam derivatives containing the 1,2,3-triazole moiety. All the compounds were evaluated for their in vitro antimicrobial and antimalarial activities. Moderate to excellent antimalarial activities were encountered. The results showed that compounds 5a, 5c, 5f, 5iexhibited the most potent antimalarial activity with IC50values of 0.85, < 0.97, < 0.97, 1.81 µM against chloroquine-resistant P. falciparumK1 strain. A QSAR study highlights the structure–activity relationships that correlate the observed antimalarial activities with changes in the compounds’ structural features.

According to the intensive physical and mental risk of methamphetamine (crystal) on human, it is important to focus on the prevention of distribution and decrease of the usage of methamphetamine. In the current study, attempts was on the application of GC–MS analysis combined with chemometrics to present a classification model for methamphetamine samples seized in different regions of Iran. In this work, principal component analysis was not able to discriminate samples from different geographic regions. For the discrimination goal, partial least squares discriminant analysis (PLS-DA) and extended canonical variate analysis (ECVA) were utilized and a classification model was constructed to differentiate methamphetamine samples seized in three regions of Iran, i.e., south, west and central. PLS-DA showed good performance in calibration step; however, ECVA indicated better prediction ability. The difference of the classified samples can be because of difference in the synthetic root used in each of three investigated regions. Class sensitivity and selectivity for all three regions were excellent in ECVA model with nonsignificant misclassifications. Cross-validation and external validation using a test set confirmed the obtained classification model. Statistical results indicated a regional production/distribution pattern in the country.

The vast majority of studies investigating the relationship between dairy working and respiratory impairments are cross-sectional and longitudinal studies are scarce. The present study aimed to assess respiratory impairments and risk factors in a group of dairy workers in a modern livestock complex. Ninety-six male dairy workers and 87 sex-matched referent workers were studied. Pulmonary function parameters were derived from the workers’ medical records. Respiratory symptoms were assessed using the European community respiratory health survey questionnaire. The workers’ exposure to bioaerosols was also assessed. The majority of dairy workers (93.8%) were never smokers. The means of all pulmonary parameters were significantly lower in the dairy workers than in the referent group. A significantly higher prevalence of shortness of breath (17.7%), wheezing (15.6%), and chest tightness (13.2%) was observed in the diary workers than in the referent group. Exposure to dairy pollutants, duration of exposure, smoking, overweight, and obesity were significant predictors of impaired pulmonary function. Dairy farming was associated with reductions in pulmonary parameters with a pattern consistent with obstructive ventilatory disorders. Significant reductions in VC (–0.98; P<0.001), FVC (–0.38; P<0.001), FEV1 (–1.28; P<0.001), FEV1/FVC (–1.10; P<0.001), and PEF (–0.49; P<0.001) by one-year increment in the duration of exposure were observed.

Edible oils are used in the preparation of foods as a part of their recipe or for frying. So to ensure of food safety, checking the quality of the oils before and after usage is an important subject in food control laboratories. In this study, edible oils from four different sources (canola, corn, sunflower and frying) were heated for 36 h at 170 °C and sampling was done every 6 h. The free fatty acid, peroxide value and the content of some fatty acids (C16:0, C18:0, C18:1, C18:2, C18:3) of the oil samples were determined by standard methods. Then, the ATR-FTIR spectra of the samples were collected. The partial least squares (PLS) regression combined with genetic algorithm was performed on the spectroscopic data to obtain the appropriate predictive models for the simultaneous estimation of acid value, peroxide value and the percentage of five kinds of fatty acids. The effect of some preprocessing methods on these models was also investigated. Preprocessing of data by orthogonal signal correction (OSC) resulted in the best predictive models for all oil properties. The correlation coefficients of calibration set (>0.99) and validation set (>0.86 and in most case >0.94) of the OSC–PLS model suggested suitable predictive modeling for all studied parameters in the oil samples. This method could be suggested as a rapid, economical and environmental friendly technique for simultaneous determination of seven noted parameters in the edible oils.

The oxygen-containing free radical species form upon interaction of amphiphilic substances such as sodium dodecyl sulfate and hemoglobin. Under these conditions, hemoglobin is converted to methemoglobin and simultaneously results in heme degradation. Since heme is located in a hydrophobic moiety of hemoglobin, we hypothesized that other hydrophobic substances or amphiphilic xenobiotics can dispose hemoglobin to oxidative stress. Here this hypothesis was tested by investigating heme degradation of hemoglobin during interaction with n-alkyl sulfates. This was accomplished using UV–Vis and fluorescence spectroscopy, chemometric analysis, and chemiluminescence methods. We determined whether a relationship exists between the alkyl tail length (surfactant hydrophobicity) of n-alkyl sulfate homologues, reactive oxygen species (ROS) production, and heme degradation pattern of hemoglobin. We also proposed a mechanism for these types of interactions and induction of heme degradation. Our results indicated that hemoglobin structural–functional changes including globin denaturation are the key factors in starting the heme degradation process, and heme degradation product patterns were dependent on each alkyl sulfate. However, the number of fluorescent components (heme degradation products) was independent of the alkyl sulfate type. The reason for this phenomenon was the mechanism of reaction in which the amount of hydrogen peroxide was changed with each homologue, but the mechanism of degradation remained the same. Thus, an increase in hydrophobic chain length of the surfactants correlated with the enhanced ROS production and heme degradation of hemoglobin.

Abstract: The first evidence of a green, single-step, and additive-free process for the fabrication of silver/silver chloride nanoparticles (Ag/AgCl NPs) by fruit extract of Syzygium cumini(S. cumini) without the usage of any stabilizer and halide source was provided. The formation of nanoparticles was optimized to control the shape, size, and stability via various pHs of the reaction mixture, the quantity of fruit extract, temperature, concentrations of silver ion, and reaction time. The optimal conditions were determined: pH = 7.0, the quantity of the leaf extract = 3.0 mL, silver ion concentration = 1.0 mM, temperature = 60 °C, and incubation time = 40 min. As an application in colorimetric sensing, the ability of the prepared Ag/AgCl NPs to sense clindamycin and Fe3+ion in an aqueous medium was investigated. The SPR band and color of the solution of Ag/AgCl NPs undergo dramatic changes in exposure to clindamycin with new SPR peaks appearing at 500 nm, accompanied by a color change from yellow to pink due to the aggregation of NPs. Under the optimized pH of 3.0, this sensor was shown a linear dynamic range from 10.0 to 100.0 µM with a LOD of 1.2 µM and good linear relationships (R2= 0.99) for clindamycin. On the other hand, the quenching of the SPR peak at 412 nm was used to monitor the Fe3+ions with wide linear ranges of 10.0–350.0 µM under the optimized pH (pH = 9) with a LOD of 5.6 µM. In addition, the proposed sensor displayed applicability in the real sample containing clindamycin (in capsules and injection ampoules) and Fe3+ions (in water samples) detection. Graphical Abstract:

Interactions of camel serum albumin (CSA) and human serum albumin (HSA) with sodium dodecyl sulphate (SDS) were studied via fluorescence and circular dichroism (CD) spectroscopy and tensiometry. There was a good correlation between fluorescence intensity and surface tension changes of CSA and HSA versus SDS concentration in which both showed two main transitions. However, the CD signals of CSA at 222 nm versus SDS concentration showed only one transition. According to the obtained results, interaction of SDS with the proteins can be divided into four distinct regions; in the initial region, SDS binds specifically to high-affinity binding sites, in the second region, SDS binds to the lower affinity binding sites on the protein surface, in the third region, cooperative binding of SDS triggers the protein to unfold. Finally after saturation of protein with SDS, at the final stage, normal SDS micelles start to form. Our results indicated that the partial unfolding of HSA started at higher concentrations of SDS and proceeded with higher cooperativity compared to that of CSA. This may be attributed to a higher inner hydrophobicity and higher stability of HSA compared to CSA.

An optical sensor was developed for measuring the concentration of l-cysteine (Cys) based on the immobilization of an ARS–Cu complex to a transparent triacetylcellulose film. The spectrophotometric studies of the sensing films clearly indicate that the absorption enhances at 438 nm and decreases at 535 nm in acetate buffer solution pH 5.0 as a result of the interaction of Cys with Cu2+of the copper–ARS complex and the reduction of Cu2+to Cu+which cause the release of ARS. With the optode membrane described, Cys in a sample solution can be determined with the linear range of 47.8 to 637.0 μM which was improved to 18.9–672.0 μM by applying the PC-ANN algorithm. The proposed optode obtained a limit of detection equal to 7.32 μM and its response time was about 16 min, depending on the concentration of Cys. The measurements of Cys in a real sample viathe new optical sensor have shown an excellent correlation with values obtained for the same samples using HPLC as a standard method.