Fabrication and characterization of hybrid eco-friendly high methoxyl pectin/gelatin/TiO2/curcumin (PGTC) nanocomposite biofilms for salmon fillet packaging.

Hybrid eco-friendly nanocomposite films were fabricated by blending high-methoxyl pectin, gelatin, TiO2, and curcumin through the solution casting method. Various concentrations (0-5 wt%) of TiO2 nanoparticles (TNPs) and curcumin as an organic filler were added to the blend solutions. A high TNP concentration affected the surface morphology, roughness, and compactness of the films. Additionally, 3D mapping revealed the nanoparticle distribution in the film layers. Moisture content, water solubility, and light transmittance reduced dramatically with increasing TNP content, in accordance with the water vapor and oxygen permeabilities. X-ray diffraction revealed that the films were semicrystalline nanocomposites, and the thermal properties of the films increased when 5 wt% of TNPs was incorporated into the blend solution. Fourier-transform infrared and Raman analyses revealed interactions among biopolymers, nanoparticles, and organic fillers through hydrogen bonding. The shelf life of fresh salmon fillets was prolonged to six days for all groups, revealed by total viable counts and psychrotrophic bacteria counts, and the pH of the salmon fillets could be extended until the sixth day for all groups. Biodegradation assays demonstrated a significant weight loss in the nanocomposite films. Therefore, a nanocomposite film with 5 wt% TNPs could potentially be cytotoxic to NIH 3T3 cells.

Biodegradable polymer-nanoclay composites as intestinal sleeve implants installed in digestive tract for obesity and type 2 diabetes treatment.

Obesity and type 2 diabetes have become serious health problems in 21st century. Development of non-invasive treatment to treat obesity and type-2 diabetes is still unmet needs. For targeting on this, one of the promising treatments is to implant an intestine sleeve in the gastrointestinal tract for limitation of food absorption. In this context, biodegradable polymer intestine sleeve was composed of polycaprolactone (PCL), poly-DL-lactic acid (PDLLA) and disk-shape nano-clay (Laponite®), and fabricated as an implantable device. Here, Laponite® as a rheological additive to improve the compatibility of PCL and PDLLA, and the polymers/clay composites were also evaluated by scanning electron microscopy SEM analysis and mechanical measurements. The mass ratio 90/10/1 of PCL/PDLLA/Laponite® composite was selected for fabrication of intestine sleeve, because of the highest toughness and flexibility, which are tensile strength of 91.9 N/mm2 and tensile strain of 448% at the failure point. The prepared intestine sleeve was implanted and deployed at the duodenum in type2 diabetic rats, providing significant benefits in control of the body weight and blood glucose, while compared with the non-implanted type 2 diabetic rats. More importantly, the food intake records and histopathological section reports presented that the implanted rats still have normal appetites and no noticeable acute symptoms of inflammation in the end of the test. These appreciable performances suggested the implantation of biocompatible polymer composites has a highly potential treatment for obesity and type 2 diabetes.

Entrapment of an adenine derivative by a photo-irradiated uracil-functionalized micelle confers controlled self-assembly behavior.

HYPOTHESIS: Invoking cooperative assembly of the uracil-functionalized supramolecular polymer BU-PPG [uracil end-capped poly(propylene glycol)] upon association with the nucleobase adenine derivative A-MA [methyl 3-(6-amino-9H-purin-9-yl)propanoate] as a model drug provides a new concept to control and tune the properties of supramolecular complexes and holds significant potential for the development of safer, more effective drug delivery systems. EXPERIMENTS: BU-PPG and A-MA were successfully developed and exhibited specific recognition and high affinity, which enabled reversible complementary adenine-uracil (A-U) hydrogen bonding-induced formation of spherical micelles in aqueous solution. The self-assembly and controllable A-MA release behavior of BU-PPG/A-MA micelles were studied using morphological analysis and optical and light scattering techniques to investigate the effect of photoirradiation and temperature on the complementary hydrogen bond interactions between BU-PPG and A-MA. FINDINGS: The resulting micelles possess unusual physical properties, including controlled photoreactivity kinetics, controllable self-assembled morphology and low cytotoxicity in vitro, as well as reversible temperature-responsive behavior. Importantly, irradiated micelles exhibited excellent long-term structural stability under normal physiological conditions and serum disturbance. Increasing the temperature triggered rapid release of A-MA by disrupting A-U complexes. These findings represent an entirely new, promising strategy for the development of multi-controlled release drug delivery nanocarriers based on complementary hydrogen bonding interactions.

Supplementing multi-functional groups to polysulfone membranes using Azadirachta indica leaves powder for effective and highly selective acid recovery.

Moderate and eco-pleasing ion-exchange trade membranes are in need to recover acid from industrial waste. Present study is focused on incorporation of plant waste (Azadirachta indica, neem leaves powder (NP)) of different composition as filler to polysulfone (PSf) membrane matrix to achieve acid recovery. Membranes were characterized, their chemical, mechanical and thermal stabilities and effectiveness in acid recovery via diffusion has been inspected. Multi-functional groups (-COOH, -NH2, -OH, -OAc, -C = O) present in different components of NP contributes in their own means in H+ ion transportation through membrane in acid recovery. They assisted formation of hydrogen bond and provided channels for ion permeation, and facilitated selective transportation of H+ ion over Fe2+ ions and explained mechanism is in accordance with Grotthuss-type and vehicle mechanism. Membrane with 15% of NP showed better performance in terms of ion exchange capacity (IEC) and acid recovery, at optimum concentration of NP, composite the membrane showed highest IEC values of 3.9771 mmol/g, UH+ value of ≈46.499 × 10-3 m/h and greater separation factor ≈154, which is higher than commercially available DF-120 membrane. An original thought of utilizing NP in membrane matrix opens up promising opportunities for extremely straightforward, easy, cost-effective and greener methods of recovery acid.

Forward osmosis membrane bioreactor for wastewater treatment with phosphorus recovery.

A forward osmosis membrane bioreactor (OMBR) with a thin film composite membrane was seeded with flocculated sludge and aerobic granules to treat a synthetic wastewater with 1M NaCl as draw solution. The tested OMBR showed 96%, 43% and 100% removal of PO4(3-)-P, NH4(+)-N, and total organic carbon. Salinity was accumulated in OMBR principally owing to membrane rejection and salt leakage from draw solution. At high salinity level membrane fouling could be induced. Intermittent withdrawal and replenishment of supernatant from OMBR maintained its operation stability, while phosphorus in withdrawn supernatant was recovered by pH adjustment. The OMBR enriched phosphorus concentration from 156 mg/L in feed solution to 890-990 mg/L. At pH 8.5 with 2.65-2.71 g 3 M NaOH/g-P, 814-817 mg-P/L was recovered in the form of sodium hydrogen phosphite hydrate. The OMBR is a volatile wastewater treatment unit with capability for enrichment and recovery of phosphorus at reduced chemical costs.