In this study, new composite bisphosphonate delivery systems were obtained from polyurethanes (PUs) and nanocrystalline hydroxyapatite (HA). The biodegradable PUs were first synthesized from poly(ε-caprolactone) diols (PCL diols), poly(ethylene adipate) diol, 1,6-hexamethylene diisocyanate, 1,4-butanediol and HA. Moreover, the PCL diols were synthesized by the ring-opening polymerization cataly...

Heterogeneous catalysts have been synthesi zed by the conjugation of Hoveyda-Grubbs second-generation catalyst with a lipase. The catalytic properties of the organometallic compound in solution were firstly optimized, evaluating the activity of Ru in the ring-closing metathesis of diethyldiallymalonate at 25 °C at different solvents and in the presence of different additives. The best result wa...

During crystallization screenings of commercially available hydrolytic enzymes, the new, hexagonal crystal form of CAL-B, has been discovered and hereby reported. The NAG molecules, which were closing the glycosylation site in the orthorhombic form, in hexagonal structure make the glycosylation site open. It is unknown whether the opening and closing of the glycosylation site by the 'lid' NAG m...

Sol-gel entrapment is an efficient immobilization technique that allows preparation of robust and highly stable biocatalysts. Lipase from Candida antarctica B was immobilized by sol-gel entrapment and by sol-gel entrapment combined with adsorption on Celite 545, using a ternary silane precursor system. After optimization of the immobilization protocol, the best enzyme loading was 17.4 mg/g supp...

The immobilization of Candida antarctica lipase type B on activated carbon was studied. Adsorption conditions were investigated in order to improve enzyme activity and stability in organic media. Results showed that biocatalyst activity and recovered activity were improved with increasing concentrations of ammonium sulphate on the supernatant during enzyme adsorption. Hydrophobic interactions w...

Candida antarctica Lipase B (CALB) was covalently immobilized onto epoxy-activated macroporous poly(methyl methacrylate) Amberzyme beads (235 microm particle size, 220 A pore size) and nanoparticles (nanoPSG, diameter 68 nm) with a poly(glycidyl methacrylate) outer region. Amberzyme beads allowed CALB loading up to 0.16 g of enzyme per gram of support. IR microspectroscopy generated images of A...

Lipase catalysis was successfully employed to synthesize high molecular weight poly(butylene succinate) (PBS). Attempts to copolymerize succinic acid with 1,4-butanediol were unsuccessful due to phase separation of the reactants. To circumvent this problem, monophasic reaction mixtures were prepared from diethyl succinate and 1,4-butanediol. The reactions were studied in bulk as well as in solu...

The synthesis of two biocatalysts based on a commercial Candida antarctica lipase B, CALB enzyme (E), physically immobilized silica supports, was carried out. first support periodic mesoporous organosilica (PMO) and the second one modified with octyl groups (octyl-MS3030). maximum load 122 mg enzyme/g PMO 288 octyl-MS3030. In addition, biocatalytic efficiency corroborated by reaction tests hydr...

Chemoenzymatic cascades are an important tool for advanced synthesis in chemistry. However, these often limited due to the incompatibility issue between two distinct catalysts and reactions. To address this issue, we present a simple multistep one-pot platform, which nanoparticle prepared allow chemo- biocatalytic reactions performed sequentially water Pickering emulsions. The preparation of pa...