Synthesis and structural characterization of elastin-based polypentapeptide/hydroxypropylmethylcellulose blend films: Assessment of miscibility, thermal stability and surface characteristics

Insights into the Physicochemical Characteristics and Miscibility of Chitosan/Polypeptide Blends: Promising Material for Wound Healing in Sprague-Dawley Rats

In this study, the synthesis of poly(AVGVP) [where A-Alanine, V-Valine, G-Glycine, and P-Proline] is executed by the stepwise solution phase method. The interaction between Chitosan and synthetic polypentapeptide in blends was examined in the liquid and solid phases. Viscosity criteria that establish the total miscibility with Chitosan are the Δ[η]m, the intrinsic viscosity [η], Huggins coefficient [KH], by Garcia ΔB, α by Sun, and μ suggested by Chee, ΔK, and β buttressed by Jiang and Han. Besides, the results are corroborated in the solid phase by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Miscibility in the blends led to higher thermal stability than that of pure polymers, according to thermogravimetric analysis (TGA). In vitro, studies offered the absence of cytotoxicity, and in vivo histopathological results advocated that the blend shows less inflammation and is more compact as against cotton gauge, evincing an enhanced healing environment and promising the possibility of use in wound therapeutic applications.

Green synthesis of Fe and Zn-NPs, phytochemistry and pharmacological evaluation of Phlomis cashmeriana Royle ex Benth

This investigation portrays the phytochemical screening, green synthesis, characterization of Fe and Zn nanoparticles, their antibacterial, anti-inflammation, cytotoxicity, and anti-thrombolytic activities. Four dissimilar solvents such as, n-hexane, chloroform, ethyl acetate and n-butanol were used to prepare the extracts of Phlomis cashmeriana Royle ex Benth. This is valued medicinal plant (Family Lamiaceae), native to mountains of Afghanistan and Kashmir. In the GC-MS study of its extract, the identified phytoconstituents have different nature such as terpenoids, alcohol and esters. The synthesized nanoparticles were characterized by SEM, UV, XRD, and FT-IR. The phytochemical analysis showed that the plant contains TPC (total phenolic content) 297.51 mg GAE/g and TFC (total flavonoid content) 467.24 mg CE/g. The cytotoxicity values have shown that the chloroform, n-butanol and aqueous extracts were more toxic than other extracts. The anti-inflammatory potential of n-butanol and aqueous extracts was found higher than all other extracts. Chloroform and n-hexane extracts have low MIC values against both E. coli and S. aureus bacterial strains. Chloroform and aqueous extracts have great anti-thrombolytic potential than all other extracts. Overall, this study successfully synthesized the nanoparticles and provides evidence that P. cashmeriana have promising bioactive compounds that could serve as potential source in the drug formulation.

Investigation of miscibiliy and physicochemical properties of synthetic polypeptide with collagen blends and their wound healing characteristics

A suitable condition is needed to foster a rapid recovery of wounds, which is a dynamic and intricate process. The development and characterization of mats of plastic-like peptide polymer (PLP) with collagen for wound healing applications are reported in this work. Viscosity parameters such as the Huggins coefficient [KH], the intrinsic viscosity [η], α by Sun, ∆[η]m by Garcia ∆B and μ suggested by Chee, ∆K, and β advocated by Jiang and Han, recommend the miscibility of the polypeptide in solution phase. Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray diffraction (XRD) methods in a solid phase. Thermal characteristics using a differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA) showed higher stability for the blends than the pure polymers. The collagen and PLP blends showed exceptional in vitro cytocompatibility, and the in vivo wound-healing studies on the Sprague-Dawley rats demonstrated faster wound healing within two weeks compared to the cotton gauze-treated injuries. Therefore, these membranes can be a possible alternative for treating skin injuries.

Flaxseed mucilage/calcium phosphate composites as bioactive material for bone tissue regeneration

Biocompatible polymers are attractive material for the manufacturing of surgical implants which break down in vivo without the necessity for a consequent operation for removal. Elaboration of composite biomaterials scaffolds as artificial bone graft materials remains a major task in bioengineering. Flaxseed mucilage was used as bioactive polysaccharide for preparing composite scaffolds made of calcium phosphate embedded in mucilage matrix. Calcium chloride was mixed with mucilage followed by the addition of phosphate precursor to stimulate the in situ formation of calcium phosphate. The obtained scaffolds mucilage/calcium phosphate at different pHs (5 and 8) were characterized using FTIR, XRD, TGA, SEM/EDX and TEM. The results showed the formation of two phases: mucilage/dicalcium phosphate dihydrate (MU/brushite) and mucilage/hydroxyapatite (MU/HA). MTT test was applied to evaluate viability of MC3T3-E1 osteoblasts cells, and the formed hybrids at various pH conditions were classified as non-cytotoxic. These findings establish the potential of developed composite to be used as bone graft substitute materials.

Polyesters Incorporating Gallic Acid as Oxygen Scavenger in Biodegradable Packaging

Biodegradable polyesters polybutylene succinate (PBS) and polybutylene adipate-co-terephthalate (PBAT) were blended with gallic acid (GA) via cast extrusion to produce oxygen scavenging polymers. The effects of polyesters and GA contents (5 to 15%) on polymer/package properties were investigated. Increasing GA formed non-homogeneous microstructures and surface roughness due to immiscibility. GA had favorable interaction with PBAT than PBS, giving more homogeneous microstructures, reduced mechanical relaxation temperature, and modified X-ray diffraction and crystalline morphology of PBAT polymers. Non-homogenous dispersion of GA reduced mechanical properties and increased water vapor and oxygen permeability by two and seven folds, respectively. Increasing amounts of GA and higher humidity enhanced oxygen absorption capacity, which also depended on the dispersion characteristics of GA in the matrices. PBAT gave higher oxygen absorption than PBS due to better dispersion and higher reactive surface area. GA blended with PBAT and PBS increased oxygen scavenging activity as sustainable active food packaging using functional biodegradable polymers.