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Background and Purpose: Designing and manufacturing controlled drug release systems can be highly beneficial in improving drug treatment methods. The aim of this study is to synthesize SBA-16 nanosilica and evaluate its use as a drug carrier for carbamazepine. Additionally, this research aims to assess the effects of pH, contact time, temperature, initial drug concentration, and adsorbent amount on the performance efficiency of the drug carrier. Materials and Methods: In this study, carbamazepine (obtained from the Food and Drug Organization of Iran), double-distilled water, 1-butanol, hydrochloric acid, pluronic copolymer F127, tetraethyl orthosilicate, and sodium hydroxide were used. All chemicals were sourced from Sigma-Aldrich and Merck. A dialysis bag manufactured by Sigma-Aldrich (14000 MWCO, 99.99% retention) was used for drug release experiments. The equipment used in this research includes a digital scale (EJ 303), pH meter (ST 2100), oven (Memmert), magnetic stirrer (HOTPLATE STIRRER 81), electric furnace (Shimaz), FT-IR device (Magna-IR Spectrometer 550 Nicolet), X-ray diffraction device (STADIP), scanning electron microscope (MIRA3-LMU), UV-Vis spectrophotometer (DB20-UV), and BET analyzer (NanoSORD92). SBA-16 was synthesized using the sol-gel method. XRD, FTIR, SEM, and EDX analyses were employed to identify and characterize the synthesized adsorbent. The effects of pH, adsorbent amount (nanocarrier), drug concentration, temperature, and contact time were evaluated using the response surface method (RSM) with the central composite design (CCD) in the Design of Experiments software (DOE) to determine optimal conditions and maximum drug loading capacity. Langmuir, Freundlich, and Temkin adsorption isotherms were used for adsorption studies, and thermodynamic and kinetic studies were also conducted. The dialysis method was applied for drug release experiments, providing physical separation and allowing easy sampling at different time intervals. Results: In this study, SBA-16 nanosilica was successfully synthesized, and scanning electron microscope (SEM) images of the SBA-16 surface demonstrated that it had a spherical and homogeneous morphology with particle sizes ranging from 2 to 50 nm. Additionally, the XRD spectrum showed that SBA-16 had a regular structure. Experiment design was used to investigate the effects of key parameters. After conducting the tests, the results were input into the software to generate the best model for evaluating and describing the data. Of the four models (linear, interaction, quadratic, and cubic), the software proposed the quadratic model as the most consistent with the responses. According to the software output, the nanocarrier was able to adsorb 99.87% of carbamazepine under optimal conditions (pH=2, initial drug concentration=20 ppm, drug carrier amount=0.05 g, temperature = 30°C, and contact time=12 minutes). The adsorption data fit the Langmuir isotherm most closely (R²=0.9996). Thermodynamic studies revealed that the adsorption process is spontaneous, exothermic, and physical, following first-order kinetics. The drug release data corresponded with the theoretical kinetic model presented by Zeng et al. (2012) for drug release from mesoporous silica nanoparticles, which assumes an initial burst release in the early hours followed by a slow and steady release. Conclusion: The nanocarrier introduced in this research is a water-insoluble, non-toxic, and highly effective adsorbent for loading the drug carbamazepine. The results demonstrated that, under optimal conditions, the drug loading efficiency reached 99.87%. Additionally, the study showed controlled drug release. The adsorption process followed the Langmuir isotherm with a regression coefficient of 0.9991, while drug release followed the first-order kinetic model with a regression coefficient of 0.9996. Thermodynamic results indicated that the drug loading process is exothermic and spontaneous

In this work, nanomesopose SBA-16 was prepared from reed plant stem by green method and used to remove Phenolphthalein pollutant. The effect of different parameters (pH, initial concentration of phenolphthalein, amount of SBA-16 adsorbent, temperature and contact time) on the amount of phenolphthalein absorption by the prepared adsorbent was investigated with the help of experiment design software. The results of the predicted experiments showed that the highest absorption of phenolphthalein was in the conditions of pH=4.01, temperature 44°C, contact time 20 min, initial concentration of adsorbent 13 mg/L and amount of adsorbent 0.05 g. can be seen. In optimal conditions, the prediction of the software was 100% removal of phenolphthalein from the water environment, which actually achieved a removal of 99.46%. Considering the high potential of nanomesopore SBA-16 in removing phenolphthalein pigment, it can be considered as a suitable candidate for removing colored pollutants and treating wastewater from textile factories.

In this study, amoxicillin from aqueous solutions was adsorbed by activated carbons from eucalyptus leave and wheat straw through adsorption process. The effects of varying parameters such as initial pH of amoxicillin solution, initial concentration of amoxicillin solution, adsorbent dosage, contact time and temperature on the adsorption process were examined. Under optimum conditions containing pH 11, amoxicillin initial concentration 10 mgL-1, adsorbent dosage 0.07 g, contact time 30 and 60 min for eucalyptus leave and wheat straw, respectively, and temperature 25±1oC, maximum adsorption percentages for amoxicillin on eucalyptus leave and wheat straw were obtained 72.4% and 79.2% respectively. In addition, comparison of the experimental results with Langmuir, Freundlich and Temkin adsorption isotherms, showed that the Langmuir isotherm have better fitting with the equilibrium data than the Freundlich isotherm but the fitting with Temkin isotherm is weaker for both adsorbents. Also, thermodynamic parameters of the adsorption such as 〖∆H〗^0 and 〖∆S〗^0 were calculated that theirs negative values showed that the amoxicillin adsorption on eucalyptus leave and wheat straw is an exothermic process and along with decrease of randomness, respectively. Meanwhile, the more negative value of 〖∆G〗^0 at 25oC compared to higher temperatures is a sign of more spontaneous adsorption process at this temperature. In addition, the study of adsorption kinetics showed that the amoxicillin adsorption on both adsorbents is pseudo-second order.

Background and Objective: Due to the water shortages and the presence of industrial pollutants in water resources, wastewater treatment, especially colored wastewater, is essential. The aim of this study was to treat wastewater containing Methylene Blue dye using activated carbon nanocomposite/zinc oxide nanoparticles (ZnO/AC) obtained from canola oil waste by green method. Materials and Methods: In the present study, the effect of different parameters (pH, Methylene Blue concentration, adsorbent amount, temperature and contact time) on the adsorption of Methylene Blue was investigated. Design of Experiment 7 software (Response Surface Method (RSM)) was used to evaluate the influence of various parameters on Methylene Blue removal. Results: The results of the predicted experiments showed that the highest adsorption of Methylene Blue is at pH = 10, temperature 70 °C, contact time of 50 min, initial adsorption concentration of 10 mg/ L and adsorbent amount of 0.05 g. Under optimal conditions, ZnO/AC adsorbent was able to remove 98.22% of Methylene Blue from the aqueous medium. Conclusion: Appropriate to the high potential of ZnO/AC nanocomposite in the removal of Methylene Blue pigment, it can be a good candidate for the removal of dye contaminants and wastewater treatment of textile factories.

In this study, the effects of solvent on the electrode potentials of menthol and carvacrol species were investigated experimentally and computationally and their antioxidant properties were compared in different solvents by calculating the half-wave potential E1/2 of species, Vand Dissociative Energy (BDE), Ionization Energy (IE), and Electron Affinity (EA). Electrochemical behavior of menthol and carvacrol species in four solvents (MeOH, EtOH, DMSO, and Heptane) were studied using cyclovoltametric technique in a glass electrode as a working electrode and the calculations for obtaining the electrode potential were performed using DFT functional including B3LYP with 6-311+G(d,p)basis set and PCM and IEFPCM models for calculation of solvent energy. Finally, the results were compared and confirmed by experimental methods. Where in the compound carvacrol represent more properties antioxidant than menthol due to lower values E1/2 in gas and solution phases. Also, the lower BDE in the gas phase is 80.19 kcal/mol compared with menthol (98.91 kcal/mol). Moreover, compound carvacrol has the IE value of 1.12 eV smaller than menthol and has the EA value of 0.35 eV higher than menthol. Calculations show that the model had no effect on computational results. Also, according to the results, the antioxidant properties of carvacrol in non-polar solvents were higher due to the smaller amount of E1/2.