laponite and Hemolysis

In recent years, inorganic nanoparticles such as Laponite have frequently been incorporated into polymer matrixes to obtain nanocomposite hydrogels with hierarchical structures, ultrastrong tensibilities, and high transparencies. Despite their unique physical and chemical properties, only a few reports have evaluated Laponite-based nanocomposite hydrogels for biomedical applications. This article presents the synthesis and characterization of a novel, hemocompatible nanocomposite hydrogels by in situ polymerization of acrylamide (AAm) in a mixed suspension containing Laponite and gelatin. The compatibility, structure, thermal stability, and mechanical properties of the resulting NC gels with varied gel compositions were investigated. Our results show that the prepared nanocomposite hydrogels exhibit good thermal stability and mechanical properties. The introduction of a biocompatible polymer, gelatin, into the polymer matrix did not change the transparency and homogeneity of the resulting nanocomposite hydrogels, but it significantly decreased the hydrogel's pH-responsive properties. More importantly, gelatins that were incorporated into the PAAm network resisted nonspecific protein adsorption, improved the degree of hemolysis, and eventually prolonged the clotting time, indicating that the in vitro hemocompatibility of the resulting nanocomposite hydrogels had been substantially enhanced. Therefore, these nanocomposite hydrogels provide opportunities for potential use in various biomedical applications.

Topics: Acrylic Resins; Adsorption; Animals; Cattle; Erythrocytes; Gelatin; Hemolysis; Hydrogels; Hydrogen-Ion Concentration; Microscopy, Confocal; Nanocomposites; Serum Albumin, Bovine; Silicates; Spectroscopy, Fourier Transform Infrared; Temperature; Tensile Strength

We report a facile approach to preparing laponite (LAP) bioceramics via sintering LAP powder compacts for bone tissue engineering applications. The sintering behavior and mechanical properties of LAP compacts under different temperatures, heating rates, and soaking times were investigated. We show that LAP bioceramic with a smooth and porous surface can be formed at 800°C with a heating rate of 5°C/h for 6 h under air. The formed LAP bioceramic was systematically characterized via different methods. Our results reveal that the LAP bioceramic possesses an excellent surface hydrophilicity and serum absorption capacity, and good cytocompatibility and hemocompatibility as demonstrated by resazurin reduction assay of rat mesenchymal stem cells (rMSCs) and hemolytic assay of pig red blood cells, respectively. The potential bone tissue engineering applicability of LAP bioceramic was explored by studying the surface mineralization behavior via soaking in simulated body fluid (SBF), as well as the surface cellular response of rMSCs. Our results suggest that LAP bioceramic is able to induce hydroxyapatite deposition on its surface when soaked in SBF and rMSCs can proliferate well on the LAP bioceramic surface. Most strikingly, alkaline phosphatase activity together with alizarin red staining results reveal that the produced LAP bioceramic is able to induce osteoblast differentiation of rMSCs in growth medium without any inducing factors. Finally, in vivo animal implantation, acute systemic toxicity test and hematoxylin and eosin (H&E)-staining data demonstrate that the prepared LAP bioceramic displays an excellent biosafety and is able to heal the bone defect. Findings from this study suggest that the developed LAP bioceramic holds a great promise for treating bone defects in bone tissue engineering.

Topics: Adsorption; Animals; Biocompatible Materials; Bone and Bones; Calcification, Physiologic; Cell Differentiation; Ceramics; Female; Hemolysis; Male; Materials Testing; Mesenchymal Stem Cells; Microscopy, Electron, Scanning; Osteogenesis; Rats, Sprague-Dawley; Serum; Silicates; Sus scrofa; Tissue Engineering; X-Ray Diffraction