Supercritical Impregnation of PETG with Leaf Extract: Influence of Operational Parameters on Expansion Degree, Antioxidant and Mechanical Properties.

PETG (poly(ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate)) is an amorphous copolymer, biocompatible, recyclable, and versatile. Nowadays, it is being actively researched for biomedical applications. However, proposals of PETG as a platform for the loading of bioactive compounds from natural extract are scarce, as well as the effect of the supercritical impregnation on this polymer.

Supercritical extraction of betalains from the peel of different pitaya species.

Background: Pitaya is a fruit with high consumer acceptance and health benefits. Pitaya peel is a waste product with potential in the food industry, as an antioxidant enrichment and natural colouring. Therefore, there is an interest in recovering its constituents and searching for pitaya species with greater potential.

Antinociceptive effect of cyclic and linear diterpenoids as new atypical agonists of κ-opioid receptors obtained from four species of the Baccharis genus, and vehiculated in nanometric niosomes.

New natural analgesic compounds that act in KORs are important alternatives for potential therapeutical use in medicine. In this work, we report and compare here the antinociceptive activity displayed by cyclic and linear diterpenes, obtained from the genus Baccharis. The antinociceptive activities determined were relatively strong, in comparison whit morphine.

Screening of the Supercritical Impregnation of Leaves Extract into Filaments of Thermoplastic Polyurethane (TPU) and Polylactic Acid (PLA) Intended for Biomedical Applications.

The leaves of as agricultural waste represent a convenient source of antioxidants. In combination with supercritical CO (scCO), assisted impregnation is an interesting strategy for the preparation of biomedical devices with specific bioactivity. For this purpose, 3D-printable filaments of thermoplastic polyurethane (TPU) and polylactic acid (PLA) were employed for the supercritical impregnation of ethanolic olive leaves extract (OLE) for biomedical application.

Preservation of the Antioxidant Capacity of Resveratrol via Encapsulation in Niosomes.

Resveratrol (RSV) is a natural polyphenol which produces several benefits to human health, being the isomer the most bioactive. However, its systemic absorption is limited due to its low water solubility, that reduces the oral bioavailability, and its chemical instability (owing to the - RSV isomer conversion upon light irradiation). Thus, encapsulation of this bioactive compound is required to protect it from destructive environmental conditions.

Fluorescence quenching of p-tert-buthylthiacalix[4]arene by 1-ethyl-3-methylimidazolium bromide.

The interaction between the ionic liquid 1-ethyl-3-methylimidazolium bromide (EMIMBr) and the macrocyclic compound p-tert-buthylthiacalix[4]arene (TC4) in solution ethanol/water 3/1 V/V was investigated by spectrophotometry and spectrofluorimetry. The UV-Vis spectra of the system (EMIMBr + TC4) were completely additive. The addition of EMIMBr decreases the fluorescence of the TC4 significantly, excited at 325.

Recent Strategies in Resveratrol Delivery Systems.

Resveratrol, a natural polyphenolic stilbenoid widely found in grapes and wines, displays beneficial properties such as cardio-protective, antioxidant and anti-inflammatory activities. Trans-resveratrol (RSV) is the most bioactive and more abundant stereoisomer found in nature. Despite the positive properties of RSV, there are various factors that limit its effectiveness, including low aqueous solubility, low oral bioavailability and chemical instability.

Effect of drug molecular weight on niosomes size and encapsulation efficiency.

Encapsulation into nanocarriers, such as niosomes, is a promising way to protect them from degradation, and allow controll and target delivery of bioactive compounds. For biotechnological applications, a tight control of particle size with acceptable encapsulation efficiencies (EE) is a technological challenge, especially for hydrophilic compounds due to its capability to diffuse across biological barriers. Niosomes formulated with mixture of surfactants represent promising nanocarriers due to the advantages of non-ionic surfactants, such as low cost, versatility and enhanced physico-chemical properties.

Niosomes encapsulated in biohydrogels for tunable delivery of phytoalexin resveratrol.

A series of biohydrogels based on mixtures of kappa-carrageenan (κ-carrageenan, κ-C) and gelatin were evaluated as potential soft delivery vehicles for the encapsulation and subsequent release of non-ionic surfactant vesicles (niosomes) loaded with resveratrol (RSV). The niosomes were prepared using a mixture of amphiphilic lipids Tween 80 and Span 80 in water. The results showed that RSV-niosomes did not significantly affect the hydrogelation properties of the biopolymer mixture.

Cyclodextrin modified niosomes to encapsulate hydrophilic compounds.

Niosomes were prepared from equimolar mixtures of two non-ionic surfactants, Span 80 and Tween 80. The capability of the vesicular systems was studied through the encapsulation of two azo dyes as molecular probes of different hydrophobicity (methyl orange (MO) and methyl yellow (MY)). To improve the efficiency of the niosomes to encapsulate the dyes, we employed an additional modification of the vesicular system, adding β-cyclodextrin (β-CD) or a modified amphiphilic β-CD (Mod-β-CD) to the niosomes.