Evaluation of the Mechanical Strength and Cell Adhesion Capacity of POSS Doped PVA/CMC Hernia Patch.

Peritoneal adhesion typically occurs in applications such as abdominal, pelvic, and vascular surgery. It is necessary to develop a mechanical barrier to prevent adhesion. In this study, a novel biomaterial as a mechanical barrier is developed by combining polyvinyl alcohol (PVA) and carboxymethyl cellulose (CMC), doped with polyhedral oligomeric silsesquioxane (POSS) to prevent peritoneal adhesion. Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) methods reveal that POSS nanoparticles in the PVA matrix disrupted the intramolecular hydroxyl groups and structure of the crystal region. Electron microscopy (EM) images reveal that high concentrations of POSS (2 wt.%) cause irregular clustering in the composite matrix. As the concentration of POSS increases in the matrix, the degradation of the membranes increases, and protein adhesion decreases. In vitro cytotoxicity tests show a toxic effect on cells for PVA/CMC composite membranes, while on the other hand, the addition of POSS increases cell viability. According to the MMT test the POSS decreases cell adhesion of membranes. When comparing the POSS doped membrane to the undoped PVA/CMC membrane, an increase in the total antioxidant level and a decrease in the total oxidant level is observed.

Manipulating cell behavior on a bacterial macro-polymer poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) via tuning the S-doped graphene ratio.

Graphene is a material with various application potentials Graphene is a unique material with superiorities and has been applied in various fields for different purposes. Although studies on the utility of graphene oxide in the biomedical field are available, no evaluation has yet been done regarding the utility of sulfur doped (S-doped) graphene. The study focuses on the effect of blending the poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) membrane with sulfur heteroatom doped graphene and the evaluation of biological responses to S-doped graphene/PHBHHx. PHBHHx membranes were blended with 1%, 0.5%, 0.1% (w/v) S-doped graphene. The morphological (SEM and Microscopy), chemical (FTIR and Raman spectroscopy), and surface area (BET) characterizations of S-doped graphene/PHBHHx membranes were performed. The presence of S groups on the surface was determined with the EDS results. Besides, the swelling profile and biodegradation tendency of the membranes were evaluated. The differentiation of protein adhesion, cell viability, cell adhesion, and cell proliferation by the increasing content of S-doped graphene was examined. The contact angle analysis revealed that modification of PHBHHx with S-doped Graphene reduced the free surface energy of PHBHHx membranes. Blending with S-doped Graphene has decreased the polarity of the PHBHHx membrane. The protein adsorption on the PHBHHx membrane was determined as 10.12 ± 0.247 mg/ml. Protein absorption on 1%, 0.5% and 0.1% S-doped graphene/PHBHHx membranes were determined as 11.34 ± 0.551 mg/ml, 9.91 ± 0.294 mg/ml and 9.48 ± 0.093 mg/ml, respectively. The cell attachment to the surface decreased with the increasing amount of S-doped graphene, however, PHBHHx membranes with graphene did not affect cytotoxicity. S-doped graphene blended PHBHHx membrane seems like a suitable patch for biomedical treatments as a hydrophobic membrane where less cell adhesion and proliferation are required like the prevention of peritoneal adhesion.

A study on bone tissue engineering: Injectable chitosan-g-stearic acid putty.

BACKGROUND: Bioengineering products can help bone tissue regeneration. OBJECTIVE: There is an ongoing research for more effective biomaterials in bone regeneration. Chitosan (Ch) grafted stearic acid (Ch-g-Sa) polymer was synthesized and its usability as a putty was evaluated in this study. METHODS: The chemical structure of Ch-g-Sa polymer was investigated using Proton nuclear magnetic resonance (H-NMR) and Fourier-transformed infrared spectroscopy-attenuated total reflectance (FTIR-ATR). Thermal properties of Ch-g-Sa polymer were determined by thermal gravimetric analysis (TGA). Putties containing nano-hydroxyapatite were prepared and in-vitro degradation properties and viscosity of the putties were determined. RESULTS: The cytotoxicity, oxidation effect and osteogenic potential of the putties were investigated on MC3T3 cells while the inflammatory effect of the putties was studied on THP-1 cells. For the determination of the osteogenic effect of the putties, ALP and RUNX2 gene expression of MC3T3 cells were studied. CONCLUSION: Ch-g-Sa/HA putties are promising biomaterials for bone tissue regeneration.

VitD3-loaded solid lipid nanoparticles: stability, cytotoxicity and cytokine levels.

Vitamin D3 (VitD3) has several beneficial effects on many metabolic pathways such as immunity system, bone development. The aim of the study, encapsulation of VitD3 with solid lipids, determine encapsulation efficiency and biocompatibility of nanoparticles. Therefore, VitD3-loaded solid lipid nanoparticles (SLNPs) were developed by optimising ratios of VitD3, stearic acid, beeswax and sodium dodecyl sulphate (SDS). Thermal stability, degradation profile, crystallinity rate, encapsulation efficiency and release profile of SLNPs were determined. Cytotoxicity of SLNPs on HaCaT, L929 and HUVEC cells were investigated. Negatively charged and VitD3-loaded nanoparticles with diameters between 30 and 60 nm were obtained. SLNPs containing up to 5.1 mg VitD3 per 10 mg powder samples were obtained. Cell proliferations were stimulated after exposure with VitD3-loaded SLNPs. Besides, inflammatory response after exposure to VitD3-loaded SLNPs was evaluated via determining IL10 and TNF-alpha levels on THP-1 cells. According to the results, no inflammatory response was observed.