Polysaccharide networks, in the form of hydrogels and dried membranes based on chitosan cross-linker tripolyphosphate (TPP), were developed using a novel approach. TPP was incorporated into by slow diffusion to favor controlled gelation. By varying chitosan, TPP, NaCl concentration, transition from inhomogeneous homogeneous systems achieved. Rheology uniaxial compression tests enabled identify best performing hydrogel composition with respect mechanical properties. FTIR, (31)P NMR,...

In the quest for a bio-based and safer substitute glutaraldehyde, we have investigated 2,5 diformylfuran (DFF) as bifunctional crosslinking agent covalent immobilization of glucoamylase on amino-functionalized methacrylic resins. Immobilization experiments systematic comparison with glutaraldehyde at four different concentrations activation step showed that DFF leads to comparable enzymatic activities all tested concentrations. Continuous flow experiment confirms similar long term stability...

Infrared thermal activation (IRTA) is considered an efficient approach to accelerate reaction rates. We report the first example of application IRTA achieve surface functionalization cellulose nanocrystals (CNCs) in solvent-less conditions with epoxidized linoleic acid (ELA), synthesized by enzymatic using CaLB (lipase B from Candida antarctica) and H2O2. The final goal enhance hydrophobicity cellulosic surfaces bio-based materials, potential coating industry. extended delignified rice husk...

The present contribution aims at testing experimentally the theoretical model previously devised (Donati, I.; Cesàro, A.; Paoletti, S.; Biomacromolecules 2006, 7, 281−287) for description of interaction between alginate and nongelling Mg2+ ions. model, based on an extension counterion condensation theory, introduces a free energy affinity, ΔGaff,0, which depends monomer composition polyuronate. In work, three different alginates separately mimicking mannuronan (polyM), guluronan (polyG),...

Guar gum (GG) and gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) model drug release tests.These three approaches used to estimate the mesh size (!) polymeric network.A comparison with similar Scleroglucan systems is carried out.In case GGb, rheological NMR estimations !lead comparable results, while approach seems underestimate !.Such discrepancy attributed viscous effect some chains that, although bound network one end, can freely...

Abstract Recent evidence has led to the hypothesis that dissipation of energy through viscoelastic extracellular matrix (ECM) can play a cardinal role in directing cell‐fate decisions, but whether and how it correlates with specific cell response is at present unclear. Here, plastic 2D chitosan‐based substrates endowed different dissipative energies are developed behavior studied terms adhesion spreading. While keeping constant stress relaxation systematically decoupling overall stiffness...

The study reports the enzymatic synthesis of bio-based oligoesters and chemo-enzymatic processes for obtaining epoxidized bioplasticizers biolubricants starting from cardoon seed oil. All molecules had MW below 1000 g mol-1 were analyzed in terms marine biodegradation. data shed light on effects chemical structure, bond lability, thermal behavior, water solubility Moreover, analysis biodegradation building blocks that constituted different products allowed us to distinguish between...

Recent experimental studies have shown a preferential interaction of poly(vinylpyrrolidone) (PVP) toward the alkyl sulfate surfactants rather than those belonging to sulfonate series. To gain information on complex formation between PVP and surfactants, we performed 1H 13C NMR NOESY measurements aqueous solutions sodium decyl (C10OS) in presence absence at 1wt %. The results show that C10OS interacts with PVP, forming micelle-like clusters bound onto polymer, furthermore suggest PVP−C10OS...

Isothermal calorimetric titrations of aqueous solutions poly(ethylene glycol) (PEG) with sodium dodecyl sulfate (SDS) are known to exhibit a peculiar trend consisting endothermic and exothermic effects. This behavior was explained the formation two different mixed micellar aggregates, one characterized by hydrophobic interactions second ion−dipole association. Present NMR measurements on 13C, 1H, 23Na nuclei do not support number PEG−SDS aggregates nature. Our data rather in accordance...

Here we focus the attention on physical characteristics of a highly biocompatible hydrogel made up crosslinked alginate and Pluronic F127 (PF127). This is composite polymeric blend propose for artery endoluminal delivery an emerging class molecules named nucleic acid based drugs (NABDs). The characterization our gel, i.e. mesh size distribution PF127–alginate mutual organization after crosslinking, can significantly determine NABDs release kinetics. Thus, to explore these aspects, different...

In this study, we synthesized a new thiosemicarbazide functionalized calix[4]arene, L and its Co2+, Ni2+, Cu2+ Zn2+ transition metal complexes. For characterization several tecniques were employed: FT-IR, 1H-NMR, 13C-NMR, 15N-NMR, COSY, NOESY, ESI-Mass spectroscopy, SEM, EDS, elemental analysis. To explore the capability of function hosted on calix[4]arene scaffold for growth inhibition bacteria, fungi cancerous tumor cells, series biological evaluations performed. L, antimicrobial tests...

Abstract The bulky 1,4‐cyclohexanedimethanol was used as co‐monomer for introducing rigidity in lipase synthetized poly(itaconate)s. Poly(1,4‐cyclohexanedimethanol itaconate) on a 14 g scale at 50 °C, under solvent‐free conditions and 70 mbar using only 135 Units of B from Candida antarctica per gram monomer. mild preserved the labile vinyl group itaconic acid avoided decomposition 1,4‐cyclohexanedimethanol, both observed chemical polycondensations. Experimental computational data show that...

The present manuscript deals with the elucidation of mechanism genipin binding by primary amines at neutral pH. UV-VIS and CD measurements both in presence oxygen oxygen-depleted conditions, combined computational analyses, led to propose a novel for formation derivatives. indications collected chiral achiral allowed interpreting lactose-modified chitosan (CTL or Chitlac), which is soluble all pH values. Two types reaction their kinetics were found oxygen: (i) an interchain reticulation,...

Mixtures containing water, bovine serum albumin (BSA), and sodium taurodeoxycholate (NaTDC), a component of the bile in mammals, have been investigated wide range composition pH. Depending on concentration both solutes pH, solutions, precipitates, gels are formed. Under spontaneous pH conditions, transport properties dilute solutions indicate occurrence significant interactions between BSA surfactant. Conversely, acidic media favor formation nonsoluble protein−surfactant complexes, with...

The cyclohexane-igepal inverse microemulsion, comprehensively established for the synthesis of silica nanoparticles in an ammonia-catalyzed sol-gel process, was alternatively studied with acid-catalyzed process. Tetraethyl orthosilicate (TEOS) used as precursor, while two different aqueous phases containing either HNO(3) or HCl at concentrations, 0.1 and 0.05 M, were examined presence absence NaF, a catalyst condensation step. evolution overall reacting system, specifically hydrolysis...

Rice husk is an underexploited, low density and highly robust composite material, massively available from rice processing. Here we report two new procedures for the formulation of immobilized lipases applicable in fats oils transformations. The enzymes were covalently anchored on aldehyde groups introduced by laccase-catalysed oxidation cellulose component. method avoids use toxic glutaraldehyde while allows application recycling biocatalysts aqueous media. second used a fluidized bed...