Crucial Chemical Revelations in 45S5 Bioactive Glass via Sequential Precursor Integration Order.

Among the wet chemical nanoparticle fabrication techniques, the sol-gel process happens through hydrolysis and subsequent polycondensation reactions. The bioactive glass known as the 45S5 SiO2-Na2O-CaO-P2O5 quaternary system has intricate chemistry, yet its advantages benefit the biomedical field on an enormous scale. The order in which the ethanol and TEOS inclusions are exchanged was investigated in this work because it has a direct impact on the early hydrolysis process. Another strategy involves adding phosphate species to the sol before gelation, modifying the network chemistry, and interpreting the findings. Adding phosphate species before gelation in the biomaterial (E-Si-P) resulted in the formation of hydroxyapatite and other calcium silicate phases at 800 °C. Swapping ethanol and TEOS biomaterials (E-Si and Si-E) resulted in the sodium-calcium silicate phase only. Si-E with strong Si-O-Si siloxane rings demonstrated superior mechanical stability, hemocompatibility, and bioactivity. This compact Si-O-Si decreased the surface area of Si-E. XPS spectra revealed that E-Si-P has the lowest Na 1s binding energy (BE) and the highest BE for Si 2p. More Si-O-/Si-OH groups formed by E-Si make the network weak and decrease the surface area and protein adsorption. These differences significantly influenced the morphology, surface properties, mechanical studies, and compatibility test. This study has further unraveled the protocol to design a biomaterial with mechanical stability and load-bearing ability. In addition, the appropriate protocol to yield the desired property-rich biomaterial with preserved bioactivity, mechanical stability, cytocompatibility, as well and surface porosity has been elaborated in detail.

Rapidly derived equimolar Ca: P phasic bioactive glass infused flexible gelatin multi-functional scaffolds - A promising tissue engineering.

The study aims to design and fabricate an ultra-easier multi-functional biomedical polymeric scaffold loaded with unique equimolar Ca:P phasic bioactive glass material (BG). Gelatin (G) - 45S5 bioactive glass (BG) scaffolds were synthesized via a simple laboratory refrigerator with higher biocompatibility and cytocompatibility. The results proved that BG has enhanced bio-mineralization of the scaffolds and results support that the G: BG (1:2) ratio is the more appropriate composition. Brunauer-Emmett-Teller (BET) study confirms the higher surface area for pure Gelatin and G: BG (1:2). Scanning Electron Microscopic images display the precipitation of hydroxycarbonate apatite layer over the scaffolds on immersing it in simulated body fluid. Alkaline phosphate activity proved that G: BG (1:2) scaffold could induce mitogenesis in MG-63 osteoblast cells, thus helping in hard tissue regeneration. Sirius red collagen deposition showed that higher content bioactive glass incorporated Gelatin polymeric scaffold G: BG (1:2) could induce rapid collagen secretion of NIH 3T3 fibroblast cell line that could help in soft tissue regeneration and earlier wound healing. The scaffolds were also tested for cell viability using NIH 3T3 fibroblast cell lines and MG 63 osteoblastic cell lines through methyl thiazolyl tetrazolium (MTT) assay. Thus, the study shows a scaffold of appropriate composition G: BG (1:2) can be a multifunctional material to regenerate hard and soft tissues.

Encapsulation of Lidocaine nanoparticles in Gadus morhua derived lipoic acid.

Local Anesthetics are used clinically for anesthesia and analgesia either following surgery or for management of acute and chronic pain conditions. Liposomal Encapsulation aids in improved delivery at the tissue level. This paper deals with formulation and characterization of Gadus morhua derived liposome encapsulated Lidocaine nanoparticles. Materials and methods: Water Soluble liposomes were synthesized and encapsulated to lidocaine. The prepared liposomes were assessed using field emission scanning electron microscope, TEM, FTIR, Zetapotential, Anti-inflammatory property and Drug release kinetics. Results: The structural and morphological characters of the conjugated liposomes were studied using SEM & TEM, surface charge Zetapotential. The cumulative drug release was studied for up to 72 h in which more than 70 % of the drug was released from the Liposomal nanoparticles. FTIR revealed similar functional groups like the control. Stability of the drug was superior than the control. Conclusion: Liposomal conjugation delays the drug release which can be used in slow release applications. Improving the drug release kinetics can be advantageous in many chronic pain conditions. Additionally, the changes in the functional groups can also aid in reduction or masking of bitterness.

Influence of varying thermal treatment on bioactive material with equal Ca/P ratio: A local drug delivery system for bone regeneration.

Designing a biomaterial with excellent bioactivity, biocompatibility, mechanical strength, porosity, and osteogenic properties is essential to incorporate therapeutic agents in order to promote efficient bone regeneration. The work intended to prepare bioactive glass with tailor-made equal Ca/P (CP) ratio to obtain clinophosinaite (Cpt) as dominant phase. Clinophosinaite (Na3 CaPSiO7 ) is one of the rarest phases of bioactive glass (BG), which is supposed to play key role in bioactivity. The novelty of this work is to track the required sintering temperature to attain equimolar calcium phosphate-containing clinophosinaite phase and its behavior. Further, its consequent physicochemical and biological properties were analyzed. Phase transition from Rhenanite to Cpt, and later the Cpt emerged as dominant phase with increase of calcination temperature from 700 to 1000°C was studied. The quantifying evolution of Cpt with Rhenanite over increasing annealing temperature also results with the major morphological modifications. BET analysis confirmed the surface area and porosity (Type-IV mesoporous) were gradually elevated upto 900°C, which had contrary effect on mechanical strength. Formation of hydroxyl carbonate apatite (HCA) layer confirmed the bioactivity of the prepared samples at varying time intervals. The CP samples demonstrated better hemocompatibility in post-immersion (i.e., less than 1% of lysis) when compared with pre-immersion. Enhanced protein adsorption and cumulative release (85%) of Simvastatin (SIM) drug was attained at 900°C treatment.

Bio-inspired multifunctional collagen/electrospun bioactive glass membranes for bone tissue engineering applications.

Treatment of bone disease and disorders is often challenging due to its complex structure. Each year millions of people needs bone substitution materials with quick recovery from diseases conditions. Synthetic bone substitutes mimicking structural, chemical and biological properties of bone matrix structure will be very obliging and of copious need. In this work, we reported on the fabrication of bioinspired, biomimetic, multifunctional bone-like three-dimensional (3D) membranes made up of inorganic bioactive glass fibers matrixed organic collagen structure. The 3D structure is arranged as a stacked-layer similar to the order of apatite and neotissue formation. Comparative studies on collagen, collagen with hollow and solid bioactive glass fibers evidenced that, collagen/hollow bioactive glass is mechanically robust, has optimal hydrophilicity, simultaneously promotes bioactivity and in situ forming drug delivery. The 3D membrane displays outstanding mechanical properties apropos to the bioactive glass fibers arrangement, with its Youngs modulus approaching the modulus of cortical bone. The in vitro cell culture studies with fibroblast cells (3T3) on the membranes display enhanced cell adhesion and proliferation with the cell alignment similar to anisotropic cell alignment found in the native bone extracellular matrix. The membranes also support 3D cell culturing and exhibits cell proliferation on the membrane surface, which extends the possibility of its bone tissue engineering application. The alkaline phosphatase assessment and alizarin red staining of osteoblast cells (MG63) depicted an enhanced osteogenic activity of the membranes. Notable Runx2, Col-Type-1 mRNA, osteocalcin, and osteonectin levels were found to be significantly increased in cells grown on the collagen/hollow bioactive glass membrane. This membrane also promotes vascularization in the chick chorioallantoic membrane model. The results altogether evidence this multifunctional 3D membrane could potentially be utilized for treatment of bone defects.

Thermal treatment stimulus on erythrocyte compatibility and hemostatic behavior of one-dimensional bioactive nanostructures.

This study identifies the role and significance of heat treatment parameters on blood compatibility and hemostatic performances. Bioactive nanomaterials step annealed at 550 and 600°C enhances the biocompatibility due to the liberation of nitrate content. This also develops the anisotropic structures such as needle-like and rod-like appearances that positively improve the erythrocyte compatibility. Different stable crystalline phases such as NaCaPO4 , Na2 Ca2 Si3 O9 , and Na1.8 Ca1.1 Si6 O14 were observed for all the bioactive materials, whereas in the case of 800°C, phase transition of Na3 CaPSiO7 was perceived along with P2 O5 . Alternatively, morphology varied from cubical (600°C) to rod-like (step annealing) and further turned toward flake-like (800°C) structures. Step-annealing process decomposed the nitrate groups as well as maintained the glass network without altering the crystalline phases. As a result, bioactive nanomaterials subjected to step annealing at 550°C along with 600°C exhibited superior compatibility with erythrocytes. Bioglass heat treated at 800°C revealed incredible blood clotting efficacy, in which Ca2+ ions initiated the thrombotic effect, blood components were concentrated due to the effect of calcium, and enhances the hemostatic performance. Bioactive glass annealed below 800°C facilitates the biocompatibility, subsequently encourage bone ingrowths at in vivo. Bioglass-800°C inspired the fibrin formation and induced clot as a hemostat to control hemorrhage.

Chitosan mediated 5-Fluorouracil functionalized silica nanoparticle from rice husk for anticancer activity.

Herein, we have reported a cost-effective method of synthesizing highly efficient silica nanomaterial from rice husks for its application as a chemotherapeutic agent. Silica particle with two different sizes ~20 nm and ~40 nm were achieved from silica precursor obtained from rice husk. 5-Fluorouracil was functionalized onto the surface of silica nanoparticles by direct conjugation and chitosan mediated conjugation. Particle size analysis, zeta potential and functional analyzes were performed in systematic methodology to confirm chitosan coating and 5-Fluorouracil conjugation on silica nanoparticles. The drug loading percentage with respect to the particle size shows that ~20 nm particles have higher loading capacity. The chitosan mediated conjugation of drug shows sustained release in acidic pH and hence suitable for cancer cell-targeted delivery. The in vitro cell culture studies performed on MC3T3 fibroblast cell lines, MCF-7 and A549 cancer cell lines depicts that, compared to direct conjugation of 5-Fluorouracil, chitosan mediated drug conjugation on the surface of silica nanoparticles shows lesser toxic to fibroblast cell lines and higher toxicity towards cancer cell lines. The results of this toxicity were also confirmed from the nucleic acid spectral signature of Raman spectra treated with drug conjugated silica nanoparticles.