A chemo-drug such as cisplatin is effective for cancer treatment but remains non-specific, is susceptible to drug resistance, and induces several side effects on organ systems. Zeolitic imidazolate framework-8, a type of MOF, has gained attention, including as a drug delivery method for targeted cancer therapeutics. In this study, ZIF-8/Silica nanocomposite was synthesized using a one-pot hydrothermal technique using the Stober technique.
View Article and Find Full Text PDFThe peels of Trapa natans (TRA) and Citrullus lanatus (CIT), were modified with a variety of chemicals to boost their surface for the optimization of adsorption performance by providing a greater number of additional active binding sites. Citric acid-processed peels (TRAC and CITC) had shown more favorable adsorption performance to eradicate acid violet 7 dye (AVS). Extra and additional active sites generated after chemical processing, including hydroxyl (OH), carboxyl (COOH), amines NH, carbonyl, and ester (-O-CO-) groups, as evidenced from FTIR and SEM characterizations, may boost the potential of physicochemical integration of adsorbent surface activity in order to promote and encourage the retention of hazardous and risky AVS molecules from the water.
View Article and Find Full Text PDFMaleic anhydride-diethylenetriamine grafted on starch (st-g-(MA-DETA)) was synthesized through graft copolymerization, and the different parameters (copolymerization temperature, reaction time, concentration of initiator and monomer concentration) affecting starch graft percentage were studied to achieve the maximum grafting percentage. The maximum grafting percentage was found to be 29.17%.
View Article and Find Full Text PDFThe substrate specificity of beef heart phosphodiesterase activity and of the phosphodiesterase activity at the cell surface of the cellular slime mold Dictyostelium discoideum has been investigated by measuring the apparent Km and maximal velocity (V) of 24 derivatives of adenosine 3',5'-monophosphate (cAMP). Several analogs have increased Km values, but unaltered V values if compared to cAMP; also the contrary (unaltered Km and reduced V) has been observed, indicating that binding of the substrate to the enzyme and ring opening are two separate steps in the hydrolysis of cAMP. cAMP is bound to the beef heart phosphodiesterase by dipole-induced dipole interactions between the adenine moiety and an aromatic amino acid, and possibly by a hydrogen bond between the enzyme and one of the exocyclic oxygen atoms; a cyclic phosphate ring is not required to obtain binding.
View Article and Find Full Text PDFCyclic nucleotide derivatives have been used as a tool to investigate the existence of distinctive activating and hydrolytic sites on the phosphodiesterase from rat liver activated by cGMP (guanosine 3',5'-monophosphate). This positively cooperative enzyme was stimulated up to 30-fold by 3 microM cGMP when 3 microM cAMP (adenosine 3',5'-monophosphate) was used as substrate. All analogues were less potent activators than cGMP.
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