Affinity binding macroporous monolithic cryogel as a matrix for extracorporeal apheresis medical devices

Cytapheresis is an extracorporeal separation technique widely used in medicine for elimination of specific classes of blood cells from circulating blood. It has been shown recently to have clinical efficacy in various disease states, such as leukaemia, autoimmune disorders, rheumatoid arthritis, renal allograft rejection and sickle–cell anaemia. The current study was undertaken to produce an affinity-binding column, based upon a macroporous monolithic cryogel with a structure of interconnected pores, with pore size and low flow resistance potentially suitable for use in cytapheresis. The affinity column was produced from poly (2-hydroxyethyl methacrylate) PHEMA cryogels synthesized by free radical polymerization at -12°C.This study involved assessing haemolytic potential, and functionalisation of polymer matrix with biological ligands. Haemolytic potential of poly (2-hydroxyethyl methacrylate) cryogel was established by measuring free haemoglobin after blood filtration through the column. The anti-human albumin (antibody) was chemically coupled to the epoxy derivatised monolithic cryogels and the binding efficiency of anti-human albumin (antibody) to the cryogel was determined. Our results show that approximately 100% of Red blood cells passed through the column with no evidence of haemolysis found in blood eluted. It was found that ~82% of human serum albumin was retained on the monolithic IgG anti-human albumin cryogel matrix. The obtained results suggest that poly (2-hydroxyethyl methacrylate) monolithic cryogel is a non-haemolytic material (haemocompatible matrix) capable of functionalisation with antibody and thus can be an appropriate matrix for use in extracorporeal apheresis system

Synthetic coal fly ash-derived zeolites doped with silver nanoparticles for mercury (II) removal from water

Coal fly ash-derived zeolites have attracted considerable interest in the last decade due to their use in several environmental applications such as the removal of dyes and heavy metals from aqueous solutions. In this work, coal fly ash-derived zeolites and silver nanoparticles-impregnated zeolites (nanocomposites) were synthesized and characterized by TEM/EDX, SEM/EDX, XRD, XRF, porosimetry (BET), particle size analysis (PSA) and zeta potential measurements. The synthesized materials were used for the removal of Hg2+ from aqueous solutions. The results demonstrated that nanocomposites can remove 99% of Hg2+, up to 10% and 90% higher than the removal achieved by the zeolite and the parent fly ash, respectively. Leaching studies further demonstrated the superiority of the nanocomposite over the parent materials. The Hg2+ removal mechanism is complex, involving adsorption, surface precipitation and amalgamation

The use of composite ferrocyanide materials for the treatment of high salinity liquid radioactive wastes rich in cesium isotopes

Several factors affecting the removal of cesium from LRW, namely total salt content, pH and organic matter content, were also investigated. High concentrations of complexing organic matter significantly reduced the sorption capacity of ferrocyanide sorbents

Toxicity studies of combination of silver nanoparticles and cryogels

The combination "cryogel + nanoparticles" allows developing a new type of wound dressing, where antimicrobial properties of silver nanoparticles made have been utilized. Previous reports have shown that the production of shaped nanoparticles and the incorporation onto cryogels is feasible [1-2]. This study investigates the toxicity of these constructs to primary human dermal fibroblast cells in context of possible clinical application

High purity nanoparticles exceed stoichiometry limits in rebox chemistry: the nano way to cleaner water

A potentially cheaper and more effective way of cleaning wastewater has been discovered by scientists at Nazarbayev University and the University of Brighton researching nanotechnology [1]. It is well established that when particles are reduced to the nanoscale unexpected effects occur. Silver, for example, interacts with mercury ions in a fixed ratio of atoms (stoichiometry), typically 2:1, which presents a limit that has never been exceeded. In this project we used an alternative chemical procedure based on modified quartz sand to immobilise silver nanoparticles (NPs) with control over their size. We found that when the size of the silver NPs decreased below 35 nm the amount of mercury ions reacting with silver increased beyond the long-held limit and rose to a maximum of 1:1.2 for 10 nm sized silver

Current state of chronic wound care in Kazakhstan: focus on topical treatments

Background — The presence of chronic hard-to-heal wounds significantly affects patients’ quality of life causing pain, discomfort, decrease of mobility and consequently leads to social isolation and depression. This type of wound is more prevalent among older population. It has been estimated that up to 1-2% of the world population have this condition. The treatment of hard-to-heal wounds is expensive and long-term process, and, stresses healthcare systems of every country. Unfortunately, limited information is available about the situation with chronic wounds in Kazakhstan as the statistical data on such patients is not monitored and not registered in this country. Methods — The search was conducted by using available electronic sources, including Google Scholar, PubMed, Web of Sciences, Medline, Wiley Online Library, and Cochrane Library databases as well as hard copy versions of peer-reviewed publications in Russian, Kazakh, and English languages. Results — We have identified and analyzed current situation with wound care in the Republic of Kazakhstan. Research has demonstrated a variety of types of treatments utilized in the country, particularly the treatment of the diabetic foot.It also indicates the lack of statistics on wound care. Conclusions — The review highlights the mechanisms of wound healing process, methods for wound care, and encompasses the information available on wound healing in Republic of Kazakhstan. The article emphasizes the necessity of establishing the systemic monitoring of wound care and formation of electronic database. Apart from that, the importance of developing and manufacturing of domestic novel wound treatments have been also stressed out

High purity nanoparticles exceed stoichiometry limits in rebox chemistry: the nano way to cleaner water

A potentially cheaper and more effective way of cleaning wastewater has been discovered by scientists at Nazarbayev University and the University of Brighton researching nanotechnology [1]. It is well established that when particles are reduced to the nanoscale unexpected effects occur. Silver, for example, interacts with mercury ions in a fixed ratio of atoms (stoichiometry), typically 2:1, which presents a limit that has never been exceeded. In this project we used an alternative chemical procedure based on modified quartz sand to immobilise silver nanoparticles (NPs) with control over their size. We found that when the size of the silver NPs decreased below 35 nm the amount of mercury ions reacting with silver increased beyond the long-held limit and rose to a maximum of 1:1.2 for 10 nm sized silver

Toxicity studies of combination of silver nanoparticles and cryogels

The combination "cryogel + nanoparticles" allows developing a new type of wound dressing, where antimicrobial properties of silver nanoparticles made have been utilized. Previous reports have shown that the production of shaped nanoparticles and the incorporation onto cryogels is feasible [1-2]. This study investigates the toxicity of these constructs to primary human dermal fibroblast cells in context of possible clinical application

Nitrogen-grafted activated carbon for removing nitrate from water

Nitrate (NO3~) and nitrite (NO2~) ions are ubiquitous in the environment and considered hazardous to humans. The primary health hazard from drinking water containing NO3~ occurs when it is transformed to NO2~ in the digestive system (Robillard et al., 2006). Currently nitrate is removed from water using polymer anion exchangers. However, this process is expensive and requires a lot of brine (NaCl) for the exchanger regeneration. Alternative physicochemical methods such as reverse osmosis are expensive and inefficient. The proposed research aims to develop anion-selective nitrogen-containing activated carbon, NGAC that can be regenerated electrochemically and does not require concentrated brine for regeneration. The key to the selectivity of the NGAC is achieved by the deposition of N-bearing conductive polymers or other species such as polypyrrole, polyaniline, pyridinium, quaternary ammonium, etc. onto the AC surface. Our preliminary results indicate that the polypyrrole charge can remain stable through multiple redox cycles (at least 50)