Role In Biocompatibility Research Articles

Erythrocyte nanovesicles as chemotherapeutic drug delivery platform for cancer therapy

The use of biodegradable nanoparticles (NPs) as a carrier for therapeutic and diagnostic agents has gained immense attention in recent years worldwide. Due to their nano-size and high drug loading capacity they have several other characteristics over other nanoparticles including their role in biocompatibility and convenient release of the drug or any cargo agent at the target tumour site, these biological nanoparticles are used in a variety of applications. Due to the prolonged circulation time; erythrocytes or red blood cells (RBC's) can be used as potential drug delivery systems with the enhanced cargo-loading ability with less toxicity. In the present work, erythrocyte-derived nanovesicles were extracted from mice whole blood with consistent reproducibility. These nanovesicles, known for being efficient drug nanocarriers were encapsulated with and doxorubicin anticancer drug (1 mg/mL) for targeted cancer chemotherapy. To further understand the surface markers, present on these biologically derived nanovesicles we have used a mass spectrometry-based approach for identifying significant proteins and surface membrane lipids and their potential role as targeting ligands for cancer cells. Uniform particle size distribution is confirmed through dynamic light scattering measurements. Further cell viability and confocal microscopy studies showed the effective killing of cancer cells with these drug-loaded biocompatible nanocarriers.

Experimental Evidence of Slow Mode Water in the Vicinity of Poly(ethylene oxide) at Physiological Temperature.

In some synthetic polymers used for medical applications, hydration water in the vicinity of the polymer chains is known to play an important role in biocompatibility and is referred to as intermediate water. The crystallization of water below 0 °C observed during thermal analysis has been considered as evidence of the presence of intermediate water. However, the origin and physicochemical properties of intermediate water have not yet been elucidated. In this study, as a typical biocompatible polymer, poly(ethylene oxide) and its hydration water were investigated with the use of terahertz time-domain spectroscopy and quasi-elastic neutron scattering. The obtained results prove the existence of a significant amount of mobile water that interacts with the polymer chains even when the water content is low at physiological temperatures.

Nanoparticles-Based Hybrid Systems: Nanotechnology and Protein Engineering

The use of nanoparticles has been extensively exploited in biotechnology, materials, nanoelectronics, cancer therapy and imaging, environment and biofuel industry areas. The unique properties of the nanoparticles depends on the core of nanomaterial, the coating and functionalization agents, which play a key role in biocompatibility and targeting abilities of the nanomaterial. The functionalization can be achieved by small molecules and/or using macromolecules. Proteins are the principal macromolecules in the development of reliable and biomimetic hybrid materials for practical technological applications. Thus, in this work, protein engineering aspects involved in hybrid nanomaterials achievement are discussed.

In Vivo Chemical Sensors: Role of Biocompatibility on Performance and Utility.

In Vivo Chemical Sensors: Role of Biocompatibility on Performance and Utility.

The Effects of Organic Solvents on the Physicochemical Properties of Human Serum Albumin Nanoparticles.

Recently, applications of albumin nanoparticles as drug delivery carriers have increased. Most toxicology studies have shown that surface chemistry and size of nanoparticles play an important role in biocompatibility and toxicity. The effect of desolvating agents with different chemical properties on the size of synthesized HSA NPs was investigated. Acetone, ethanol, methanol, and acetonitrile were used to synthesize HSA NPs with controllable size by desolvation method. Scanning electron microscopy (SEM), dynamic light scattering (DLS), and circular dichroism (CD) were employed to characterize produced particles. Finally, the toxicity of HSA NPs synthesized under different conditions was evaluated on PC-12 cells. The sizes of synthesized particles differed according to the different solvents used. The sizes were 275.3 nm, 155.3 nm, 100.11 nm, and 66.2 nm for acetonitrile, ethanol, acetone, and methanol, respectively. CD showed that larger NPs had more changes in the secondary structures. Finally, the toxicity monitored on the cultured PC-12 cells showed no significant toxic effect through treating with these NPs at different concentrations (0-500 μg.mL-1). The size of HSA NPs has a strong dependency on the desolvating agent. The mechanism in which the desolvating agent affects the size of HSA NPs is complex. Various factors such as dielectric constant, polarity, functional groups, and hydrogen bonding of the solvents have the potential to affect the size and structure of HSA NPs. CD analysis suggested that the solvent denaturing capability had a critical effect on the HSA particle size. The stronger denaturing capability of the solvent resulted in the larger HSA particle size.

Electrochemical Quartz Crystal Microbalance and X-Ray Photoelectron Spectroscopy study of cathodic reactions in Bovine Serum Albumin containing solutions on a Physical Vapour Deposition-CoCrMo biomedical alloy

Protein adsorption on biomedical CoCrMo alloys plays a crucial role in biocompatibility, corrosion and wear properties of implants. So far, protein adsorption was studied only on passive CoCrMo alloys above the open circuit potential. In this work the adsorption of Bovine Serum Albumin (BSA) under cathodic conditions was investigated using a combination of Electrochemical Quartz Cristal Microbalance (EQCM) and X-Ray Photoelectron Spectroscopy (XPS) surface analysis. Results show that cathodic polarization yields larger BSA adsorption than what reported at passive potentials. The involved adsorption mechanism is related to the electrochemical controlled reduction of BSA.

콜라겐 코팅된 블록공중합(PCL/PCL-PEG) 나노섬유의 제조 및 특성분석

Electrospun polymeric nanofibers have been extensively studied for biomedical materials because of their unique structures and relatively easy fabrication with biocompatible polymers. The amount of surface exposed amine groups increases as the blend ratio of block copolymer increases. Cell attachments on the nanofibers change according to the ratio of the block copolymer ((Poly(e-caprolactone, PCL), Poly(e-caprolactone)-Poly (ethylen glycol-)) in the blend. We assume that the PEG and amine moiety plays a significant role in biocompatibility of nanofiber surfaces. Collagen was used as a grafting material on the composite nanofibers to enhance the cell adhesion because the collagen is a major constituent of connective tissue.

Effect of resin chemistry on depth of cure and cytotoxicity of dental resin composites

Abstract New dental composite restorative materials are being introduced aiming to overcome the disadvantages of contemporary materials. Hence there is a need to analyze the critical properties of these composites to aid in clinical application. This study aims to comparatively analyze the degree of conversion (DC), residual reactivity (DBC/reactivity) and cytotoxicity of 2 composites based on different resin chemistry. Ceram X and Filtek P90 were used in the study to prepare disc shaped samples of 2 mm thickness and 4 mm diameter. The samples for cytotoxicity were cured for 40 s and those of Fourier Transform Infra-red Spectroscopy (FTIR) (DBC/reactivity and DC) for 5 s, 10 s, 20 s and 40 s, at an average intensity of 800 mW/cm2 with Quartz–Tungsten–Halogen (QTH) light. DC was calculated in 60–100 μm thick and 6 mm diameter samples. Double bonds concentration/reactivity was measured in approximately 80 μm thick sections prepared from the 2 mm thick discs using a hard tissue microtome. The cell viability was scored by Trypan blue exclusion staining technique at 24 h and 48 h. Both composites showed a progressive increase in double bonds/reactivity as the distance from curing probe increased which was inversely proportional to the curing time. The DC of Filtek P90 was 20% and 96% and that of Ceram X 33% and 50% at 5 s and 40 s, respectively. Ceram X showed statistically significantly higher cell viability score at both 24 h and 48 h than Filtek P90. The results were statistically analyzed using non-parametric Kruskal–Wallis, Mann–Whitney U and Wilcoxon Signed Ranks tests. Though DC plays an important role in biocompatibility of dental composites, other factors like elution may play a significant role and hence need further evaluation.

Improving hydrophilicity and protein resistance of silicone hydrogel by plasma induced graft polymerization of 2- methacryloyloxyethyl phosphorylcholine

AbstractSurface properties of silicone hydrogels used as soft contact lenses play an important role in biocompatibility, conformability and deposition of protein. In this report, the surface hydrophilicity and protein deposition resistance of silicone hydrogel were modified using an atmospheric pressure glow discharge plasma (APGDP) induced graft polymerization of 2-methacryloyloxyethyl phosphoryl choline (MPC). Silicone hydrogel was treated with plasma and exposed to air to form oxide and hydroperoxides at the surface, which initiated surface graft polymerization of MPC. Elemental composition and structure at the surface of silicone hydrogel were characterized through ATR-FTIR and XPS. The data of ATR-FTIR and XPS analyses revealed that MPC was grafted onto the surface of silicone hydrogel. Contact angle measurement was used to evaluate the hydrophilic property of the silicone hydrogel. The MPC grafted silicone hydrogel has the contact angle about 55° when MPC solution with the concentration 10 wt% is applied for graft polymerization. The result showed that graft polymerzation of MPC improved the hydrophilicity of silicone hydrogel efficiently. Bovine serum albumin (BSA) was used as a model to investigate protein deposition resistance of the modified silicone hydrogel. The data obtained by bicinchoninic acid assay revealed that the grafted silicone hydrogels had a significant enhancement of protein resistance.

ChemInform Abstract: Recent Advances in Surface Engineering of Superparamagnetic Iron Oxide Nanoparticles for Biomedical Applications

AbstractReview: 293 refs.

Recent advances in surface engineering of superparamagnetic iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles (SPIONs) are promising materials for various biomedical applications including targeted drug delivery and imaging, hyperthermia, magneto-transfections, gene therapy, stem cell tracking, molecular/cellular tracking, magnetic separation technologies (e.g. rapid DNA sequencing), and detection of liver and lymph node metastases. The most recent applications for SPIONs for early detection of inflammatory, cancer, diabetes and atherosclerosis have also increased their popularity in academia. In order to increase the efficacy of SPIONs in the desired applications, especial surface coating/characteristics are required. The aim of this article is to review the surface properties of magnetic nanoparticles upon synthesis and the surface engineering by different coatings. The biological aspects, cytotoxicity, and health risks are addressed. Special emphasis is given to organic and inorganic-based coatings due to their determinant role in biocompatibility or toxicity of the final particles.

Glutathione depletion as a mechanism of 3,4-dideoxyglucosone-3-ene-induced cytotoxicity in human peritoneal mesothelial cells: role in biocompatibility of peritoneal dialysis fluids

The potential detrimental effects of glucose degradation products (GDPs) contained in peritoneal dialysis fluids (PDFs) on peritoneal mesothelial cells (PMCs) may impair intraperitoneal homeostasis in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). A recent study showed that 3,4-dideoxyglucosone-3-ene (3,4-DGE) was the most strongly cytotoxic among all identified GDPs in PDFs. The present study examined the effects of clinically relevant concentrations of 3,4-DGE on the proliferative capacity of PMCs and oxidative injury to them. The concentrations of eight GDPs in commercially available PDFs were determined by HPLC. The effect of cell growth media spiked with GDPs on the proliferation capacity of PMCs was evaluated. As a marker of the cellular redox status, total cellular glutathione (tGSH) was determined in PMCs incubated with GDPs. The reaction of 3,4-DGE with GSH under nonenzymatic conditions was analysed by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). The concentrations of 3,4-DGE in a heat-sterilized single-compartment standard-type PDF (S-PDF) and in a heat-sterilized dual-chamber-type PDF (N-PDF) were 16 microM and 1.7 microM, respectively. The most cytotoxic GDP was 3,4-DGE, and the concentration at which it causes 50% inhibition of cell growth was 35 microM. A significant decrease in the cellular tGSH levels was observed in the cells treated with 10 microM 3,4-DGE. 3,4-DGE disappeared on incubation with GSH under nonenzymatic conditions for 1 h, and the 3,4-DGE-GSH conjugate was confirmed by accurate mass measurement using LC-ESI-MS. These data demonstrated that the change in the cellular redox status by GSH depletion might be a contributory factor in 3,4-DGE-induced cytotoxicity. 3,4-DGE is a highly reactive GDP and is responsible for the depletion of the total intracellular glutathione. 3,4-DGE has an intense impact on PMC growth at concentrations found in standard PDFs. It is desired that the amount of 3,4-DGE in PDFs should be minimized.

Two-step elution of human serum proteins from different glass-modified bioactive surfaces: a comparative proteomic analysis of adsorption patterns.

Plasma protein adsorption patterns on surfaces may give vital information to evaluate biocompatibility of biomaterials designed for direct blood-contacting applications or tissue integration. Adsorption of human serum proteins on four different types of biomaterials (glass, aminosilanized glass, hyaluronan and sulfated hyaluronan) was analyzed by two-dimensional electrophoresis. Desorption of proteins from the surfaces was first classically achieved by sodium dodecyl sulfate (SDS) elution. We introduced a second elution step (by use of isoelectric focusing (IEF) sample buffer consisting of urea, 3-[(3-cholamidopropyl)dimethylammonio]-1-propansulfonate, and dithioerythritol) which allows more stringent elution conditions and is a tool to evaluate the protein adsorption strength to biomaterials. Moreover, the two-step elution may discriminate between irreversible and reversible adsorption of plasma proteins for biomaterials, thus helping to elucidate the structure of protein multilayers which form a complex system at the surfaces. The IEF sample buffer proved not to alter the biomaterial structure and integrity. Hydrophobic bonds resulted to be the main strength driving protein adsorption onto our biomaterials. Apolipoproteins were the most important proteins interacting with the surfaces suggesting that high-density lipoprotein (HDL) particles could play a role in biocompatibility due to their beneficial effects on endothelial cells.

Protein adsorption on topographically nanostructured titanium

We study the protein adsorption on surfaces in order to investigate their predominant role in biocompatibility. Nanostructures are created by local anodic oxidation on titanium using the atomic force microscope. A remarkable specificity of the actin filament adsorption on the nanostructure height is noticed. F-actin is observed to have a low adsorption on nanostructures of a height of 4 nm and the adsorbed proteins appear to be randomly oriented. In contrast high protein adsorption is observed for structure height between 1 and 2 nm, moreover the filaments adsorb preferentially parallel to the nanostructured pattern.