Effective Adsorption and Removal of Doxorubicin from Aqueous Solutions Using Mesostructured Silica Nanospheres: Box-Behnken Design Optimization and Adsorption Performance Evaluation.

The aim of this study is to evaluate the efficacy of mesoporous silica nanospheres as an adsorbent to remove doxorubicin (DOX) from aqueous solution. The surface and structural properties of mesoporous silica nanospheres were investigated using BET, SEM, XRD, TEM, ζ potential, and point of zero charge analysis. To optimize DOX removal from aqueous solution, a Box-Behnken surface statistical design (BBD) with four times factors, four levels, and response surface modeling (RSM) was used. A high amount of adsorptivity from DOX (804.84 mg/g) was successfully done under the following conditions: mesoporous silica nanospheres dose = 0.02 g/25 mL; pH = 6; shaking speed = 200 rpm; and adsorption time = 100 min. The study of isotherms demonstrated how well the Langmuir equation and the experimental data matched. According to thermodynamic characteristics, the adsorption of DOX on mesoporous silica nanospheres was endothermic and spontaneous. The increase in solution temperature also aided in the removal of DOX. The kinetic study showed that the model suited the pseudo-second-order. The suggested adsorption method could recycle mesoporous silica nanospheres five times, with a modest reduction in its ability for adsorption. The most important feature of our adsorbent is that it can be recycled five times without losing its efficiency.

Enhanced Adsorption and Evaluation of Tetracycline Removal in an Aquatic System by Modified Silica Nanotubes.

In the present study, a nanocomposite adsorbent based on mesoporous silica nanotubes (MSNTs) loaded with 3-aminopropyltriethoxysilane (3-APTES@MSNTs) was synthesized. The nanocomposite was employed as an effective adsorbent for the adsorption of tetracycline (TC) antibiotics from aqueous media. It has an 848.80 mg/g maximal TC adsorption capability. The structure and properties of 3-APTES@MSNT nanoadsorbent were detected by TEM, XRD, SEM, FTIR, and N2 adsorption-desorption isotherms. The later analysis suggested that the 3-APTES@MSNT nanoadsorbent has abundant surface functional groups, effective pore size distribution, a larger pore volume, and a relatively higher surface area. Furthermore, the influence of key adsorption parameters, including ambient temperature, ionic strength, initial TC concentration, contact time, initial pH, coexisting ions, and adsorbent dosage, had also been investigated. The 3-APTES@MSNT nanoadsorbent's ability to adsorb the TC molecules was found to be more compatible with Langmuir isothermal and pseudo-second-order kinetic models. Moreover, research on temperature profiles pointed to the process' endothermic character. In combination with the characterization findings, it was logically concluded that the 3-APTES@MSNT nanoadsorbent's primary adsorption processes involved interaction, electrostatic interaction, hydrogen bonding interaction, and the pore-fling effect. The synthesized 3-APTES@MSNT nanoadsorbent has an interestingly high recyclability of >84.6 percent up to the fifth cycle. The 3-APTES@MSNT nanoadsorbent, therefore, showed promise for TC removal and environmental cleanup.

Synthesis and Molecular Docking of New 1,2,3-triazole Carbohydrates with COVID-19 Proteins.

AIMS: We have established this paper to recommend a novel way for the preparation of carbohydrates encompassing a 1,2,3-triazole motif that was prepared using an efficient click chemistry synthesis. BACKGROUND: The SARS-CoV-2 coronavirus epidemic continues to spread at a fast rate worldwide. The main protease (Mpro) is useful target for anti-COVID-19 agents. Triazoles are frequently found in many bioactive products, such as coronavirus inhibitors. OBJECTIVE: Click reactions are facilitated via the activation of copper nanoparticles, different substrates have been tested using this adopted procedure given in all cases, in high yields and purity. Other interesting comparative docking analyses will be the focus of this article. Calculations of quantitative structure-activity relationships will be studied. METHODS: Copper nanoparticles were produced by the reaction of cupric acetate monohydrate with oleylamine and oleic acid. To a solution, 5-(azidomethyl)-2,2,7,7-tetramethyltetrahydro-5Hbis([ 1,3]dioxolo)[4,5-b:4',5'-d]pyran 2 (200 mg, 0.72 mmol, 1 eq.) in toluene (15 mL) was added into a mixture of N-(prop-2-yn-1-yl)benzamide derivatives 1a-d (1.5 eq.) and copper nanoparticles (0.57 mg, 0.036 mmol, 0.05 eq.). RESULTS: A novel series of 1,2,3-triazole carbohydrate skeletons were modeled and efficiently synthesized. Based on the observations, virtual screening using molecular docking was performed to identify novel compounds that can bind with the protein structures of COVID-19 (PDB ID: 6LU7 and 6W41). We believed that the 1,2,3-triazole carbohydrate derivatives could aid in COVID-19 drug discovery. CONCLUSION: The formations of targeted triazoles were confirmed by different spectroscopic techniques (FT-IR, 1H NMR, 13C NMR, and CHN analyses). The docking scores of the newly synthesized triazole are attributed to the presence of hydrogen bonds together with many interactions between the ligands and the active amino acid residue of the receptor. The comparison of the interactions of the drugs, remdesivir and triazole, in the largest pocket of 6W41 and 6LU7 is also presented.

Functionalized MOF as a Sensitive Spectroscopic Probe for Hg2+, Co2+, and Al3+ Ions Detection in Aqueous Media.

A modified metal-organic framework (MOF) named Al-MIL-53-N=SA-Br was synthesized via a Schiff-base reaction between the MOFs (Al-MIL-53-NH2) and 5-bromo salicylaldehyde. The robust functionalized Al-MIL-53-N=SA-Br was used as a novel spectrophotometric sensor for detecting Hg2+, Co2+, and Al3+ ions. In a wide range of concentrations, the absorption spectral intensity of Al-MIL-53-N=SA-Br increased linearly upon increasing the concentration of Hg2+, Co2+, and Al3+ ions. The limit of detection (LOD) of the proposed Al-MIL-53-N=SA-Br sensor reached 1.52 ppm of Hg2+ ion (7.56 × 10-9 M). Therefore, this study introduces a novel ratiometric Hg2+, Co2+, and Al3+ ions chemosensor. Simple treatment using thiourea or ethylenediaminetetraacetic acid can remove the metal ions from the used sensor and use it many times with a high efficiency. In addition, the Al-MIL-53-N=SA-Br sensor has a high adsorption capacity for these metal ions. The design of the robust Al-MIL-53-N=SA-Br sensor provided high stability, reproducibility, selectivity, high sensitivity, and a facile sensing design. Furthermore, the good absorption spectral stability of Al-MIL-53-N=SA-Br in aqueous media, the broad linear in sensing, and the low LOD of the Hg2+, Co2+, and Al3+ ions show its high potential in determining these ions in real water.

Disinfection of corona and myriad viruses in water by non-thermal plasma: a review.

Nowadays, in parallel to the appearance of the COVID-19 virus, the risk of viruses in water increases leading to the necessity of developing novel disinfection methods. This review focuses on the route of virus contamination in water and introduces non-thermal plasma technology as a promising method for the inactivation of viruses. Effects of essential parameters affecting the non-thermal discharge for viral inactivation have been exposed. The review has also illustrated a critical discussion of this technology with other advanced oxidation processes. Additionally, the inactivation mechanisms have also been detailed based on reactive oxygen and nitrogen species.

Mechanochemical Promoted Heterocycles: A Solvent-free Route to Triazole Carbohydrates as Glycogen Phosphorylase Inhibitors.

AIMS: This study aimed to recommend a novel way for the preparation of carbohydrates containing triazole derivatives. BACKGROUND: Triazoles containing derivatives have numerous biological activities. Ball milling is a fast, modest, green process with massive potential. One of the greatest interesting applications of this technique is in the arena of heterocycles. OBJECTIVE: Solvent-free click reactions are facilitated via the activation of copper powder using a ball milling mechanochemical procedure. An optimization study of parameters affecting the reaction rate, such as reaction time, size, and milling ball number, has been conducted. Different substrates have been tested using this adopted procedure considering in all cases, in high yields and purity, the corresponding chiral optically pure five-membered glycoconjugates containing 1,2,3-triazole. METHODS: Three milling balls of 10 mm in diameter were placed in the milling jar (50 mL; stainless steel). 1 mmol of alkyne, 2 mmol of azide, and 1 mmol of Cu powder (63 mg) were added, respectively, in the presented order. Milling was assured for 25 min at 650 rpm deprived of solvent. RESULTS: The cycloaddition results and the deprotection of the cycloadducts were affected by the selection of the protective groups. Cleavage of the acetyl protecting groups provided water-soluble triazoles. The four 1,4-di-substituted 1,2,3-triazoles synthesized via deacetylation were tested against glycogen phosphorylase. The best inhibitor of rabbit muscle glycogen phosphorylase was 2-Amino-3-{2-[1-(3,4,5,6-tetrahydroxytetrahydro- pyran-2-ylmethyl)-1H-[1,2,3]triazol-4-yl]-ethylsulfanyl}-propionic acid b (Ki = 40.8 ± 3.2 µM). This novel procedure affords an eco-friendly reaction profile (catalyst-free) affording high yields and short reaction times. CONCLUSION: In this work, acetyl protective groups were used to the corresponding deprotected watersoluble triazole analogous to recognizing glycogen phosphorylase inhibitors. Triazole 6a was the most effective inhibitor of RMGP b with a Ki value of 40.8 µM.