Biopolymers最新文献

Microbial ocular infections, namely bacterial conjunctivitis (BC), are a major concern in the biomedical field. Nisin (NIS) is an amphiphilic natural antimicrobial peptide. It showed antibacterial potential against Pseudomonas aeruginosa, which is responsible for BC. Despite this, the application of NIS in pharmaceuticals for the treatment of ocular infections is hindered by several limitations that include poor aqueous solubility and stability. The preference for solid lipid nanoparticles (SLN) shows the aptitude to enhance solubility, bioavailability, etc., of therapeutically active molecules. Therefore, the present research work intends to prepare a thermoresponsive poloxamer 407 (P-407)-based in situ ocular gel of NIS-incorporated SLN using Box Behnken Design (BBD) for improved antibacterial application. Herein, NIS-SLN was formulated with glyceryl monostearate (GMS) and Tween 80 using a HSH-probe sonication method. It resulted in the spherical shape NIS-SLN with the particle size (PS) of 158.8 ± 13.56 nm, zeta potential (ZP) of −22.48 ± 1.86 mV, and drug loading (DL) of 12.8% ± 2.84%. The formulated thermo-responsive in situ gel (ISG) pH, gelling temperature, and viscosity were found to be 7.45 ± 0.02, 36.5°C ± 0.5°C, and 465.5 ± 6.5 cps, respectively, with drug release of 68.65% ± 5.1% over 24 h. Moreover, it shows improved permeation of 66.43% ± 2.6%, which might be because of the nanoscale dimensions of SLN and Tween 80. The formulation demonstrates good stability for 3 months and improved antimicrobial potential against P. aeruginosa compared to pure NIS, possibly owing to sustained release and improved penetration of NIS. Moreover, in vivo experiments demonstrated no irritation of the gel formulation, confirming biocompatibility with the ocular region. In conclusion, the SLN incorporated thermo-responsive P-407-based in situ ocular gel provides the improved potential of NIS. In the future, it will reveal a new horizon for the delivery of NIS and other molecules for ocular disease treatment.

Chitosan@Magnetite composites have gained significant attention in the field of water purification due to their high capacity to absorb contaminants and their ease of separation using magnets. In this review, we reviewed the latest methods for preparing this material and explained its key properties, particularly its structural shape and the ways of modifying it to be more efficient. One of its most obvious advantages is the increase of surface area, which helps improve absorption. To this end, we mentioned several analytical techniques, such as morphology and structure, to understand how this material works. We also explained how this material can remove heavy metals and organic pollutants from water. Finally, we evaluated its performance in terms of absorption capacity, reaction rate, and its ability to be regenerated and reused, confirming its excellent suitability for practical and sustainable water purification.

A plastic film made from Gum Arabic and sorbitol (BioFilm-EAp) was developed to enhance the stability of bioactive compounds from Argemone platyceras (EAp) and preserve their antimicrobial properties. The EAp compounds identified through spectrophotometric methods in ethanolic extracts of leaves and stems included alkaloids (3320 and 1260 cm⁻¹), flavonoids (1739 cm⁻¹), and phenols (1260 cm⁻¹). Additionally, the extracts demonstrated the ability to inhibit the growth of Escherichia coli and Staphylococcus aureus. The BioFilm, with and without EAp, was characterized through mechanical tests, revealing that films containing EAp were less resistant (1.07–11.82 N) than those without compounds (23.02 N). Furthermore, these properties depended on the concentration of sorbitol. The presence of alkaloids, flavonoids, and phenols in the BioFilm-EAp was assessed qualitatively using a simple and inexpensive methodology based on UV–Vis spectroscopy. The results indicated that these compounds remained stable within the sorbitol-Gum Arabic biopolymer matrix over 21 days. Finally, a sample of grapes was coated with the BioFilm-EAp films through the solution immersion method. This coating preserved the physical parameters of the grapes stored at room temperature, while the active compounds inhibited the growth of microorganisms on the grapes.

Engineering of biomaterials for advanced skin tissue regeneration requires optimization of critical parameters including interconnected porous structure, biomaterial stability, hydrophilicity, biocompatibility, and bioactivity. These features enable the mimicry of the skin tissue microenvironment and support the key phases of the regeneration process, which are crucial for effective tissue repair. Another important requirement for successful skin tissue regeneration is the modulation of oxidative stress, as excessive accumulation of reactive oxygen species (ROS) at the site of the skin lesion can hinder healing and cause chronic inflammation and scarring. To address these challenges, we propose a reductionist therapeutic approach to skin tissue regeneration by developing bio-sourced scaffolds that replicate the native extracellular matrix (ECM), neutralize ROS levels, and actively promote tissue regeneration at both structural and molecular levels. These nano ZnO-embedded gelatin/alginate bioscaffolds were prepared via a simple crosslinking reaction and loaded with carefully selected active agents with antioxidant and skin tissue regenerative potential. Characterization studies of the bioscaffolds confirmed their porous interconnected morphology with tunable porosity (92%–94%), mechanical strength (1.95–3.22 MPa), hydrophilicity, stable adhesion to skin tissue, and ROS-scavenging activity. Additionally, the bioscaffolds demonstrated simultaneous release of quercetin, allantoin, and caffeic acid, and both biocompatibility—in vitro on human fibroblasts (MRC5) and in vivo on Caenorhabditis elegans. Overall, these findings provide valuable insight into the design of multifunctional bioscaffolds as a promising therapeutic platform for skin tissue regeneration application, which simultaneously modulates oxidative stress, replicates ECM architecture, and stimulates the healing cascade, ultimately enhancing skin tissue repair and reducing scarring.

Herein, alginate films doped with cerium(III) carbonate were prepared via the casting method. An acid treatment process was applied to the films for cross-linking by free Ce³⁺ ions. The incorporation of poly(vinyl) alcohol into the alginate matrix enhanced the film properties. Fourier transform infrared spectroscopy and differential scanning calorimetry analyses confirmed that PVA did not alter the chemical structure of the Ce/Alg films. Analysis of the morphological characteristics of Ce/Alg films using a scanning electron microscope revealed that porosity existed in the films. Cerium-alginate films rapidly swell in PBS (pH = 7.4) and water within 10 min, demonstrating their potential for effective fluid absorption in wound environments. The water vapor permeability test exhibited that the films have the ability to transmit moisture. This present work reports the formulation of cerium(III) cross-linked alginate films and characterization studies of the films. The films are regarded as subject to efficient wound coverage dressings in future studies with their favorable biomaterial properties.

Nowadays, the use of 3D printing method in the construction of scaffolds is significantly common for bone tissue engineering applications. Moreover, the addition of nanoparticles and additives can significantly improve the mechanical and biological properties of polymeric scaffolds as polymers alone are not able to show enough performances. In this study, composite scaffolds based on polycaprolactone (PCL) containing different amounts of zinc oxide (ZnO) and Baghdadite (B) nanoparticles were fabricated by 3D printing method as novel combinations for bone tissue engineering. Then, their physical, mechanical, and biological properties were investigated. The scanning electron microscopy (SEM) of the composite showed uniform and porous structures with open porosity. Fourier-transform infrared spectroscopy (FTIR) of the scaffolds confirmed that no reaction occurred between PCL, B, and ZnO nanoparticles during the fabrication of composite scaffolds. The PCL/B/ZnO composite scaffolds showed high compressive strength. They also showed weight loss during 4 weeks, which was related to PCL degradation. The high bioactivity of the composite scaffolds was confirmed by dispersive X-ray analysis (EDS). SEM images showed the formation of calcium phosphate (CaP) layer on scaffolds in simulated body fluid (SBF). Inductively coupled plasma (ICP) analysis confirmed the formation of apatite layer on their surfaces. Based on the results of the (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) (MTT) test, cell proliferation on the scaffolds increased after 72 h, which shows that the scaffolds are biocompatible and non-toxic. SEM images showed that the cells on the surface of PCL-based nanocomposite scaffolds prepared had a suitable density. The results of alizarin red staining showed a significant amount of calcium deposition on the scaffolds. It has been shown that PCL-based nanocomposite scaffolds containing B and ZnO nanoparticles are suitable candidates for use in bone tissue engineering applications as they have suitable mechanical, biological, and physical properties.