Remarkable performance of magnetized chitosan-decorated lignocellulose fiber towards biosorptive removal of acidic azo colorant from aqueous environment

Carbon nitride reinforced chitosan/sodium alginate hydrogel as high-performance adsorbents for free hemoglobin removal in vitro and in vivo

Removing free hemoglobin generated during extracorporeal circulation remains a challenge. Currently, there is no adsorbent with specificity and good biosafety for removing hemoglobin. In this study, a new chitosan/sodium alginate/carbon nitride (CS/SA/C3N4) hydrogel adsorbent was prepared by blending SA with C3N4 to drop into CS/CaCl2 solution. The physicochemical properties of CS/SA/C3N4 hydrogel were evaluated using some techniques, including scanning electron microscope, Zeta potential measurement, and thermogravimetric analysis. Hemoglobin adsorption in vitro, stability, hemocompatibility, cell compatibility, inflammatory reaction and blood extracorporeal circulation in vivo were also evaluated. The findings revealed that the CS/SA/C3N4-0.4 % hydrogel exhibited an impressive adsorption capacity of 142.35 mg/g for hemoglobin. The kinetic data of hemoglobin adsorption were well-described by pseudo second-order model, while the isothermal model data conformed to the Langmuir model. The hardness and modulus of CS/SA/C3N4-0.4 % was 11.7 KPa and 94.66 KPa respectively, which indicated robust resistance to breakage. CS/SA/C3N4 demonstrated excellent hemocompatibility, biocompatibility and anti-inflammatory properties. In addition, the results of in vivo rabbit extracorporeal blood circulation experiment demonstrated that CS/SA/C3N4 could adsorb free hemoglobin from blood while maintaining high biosafety standard. Consequently, CS/SA/C3N4 hydrogel emerges as a promising candidate for use as a hemoglobin adsorbent in extracorporeal blood circulation system.

TiO2/Polystyrene Nanocomposite Antibacterial Material as a Hemoperfusion Adsorbent for Efficient Bilirubin Removal and Prevention of Bacterial Infection

The use of hemoperfusion adsorbents for the removal of bilirubin in patients with liver failure has become a critical treatment. However, the insufficient clearance of bilirubin and the possibility of bacterial infection during hemoperfusion limit the application. In this work, we designed a novel antibacterial bilirubin adsorbent (PSVT) through the suspension polymerization reaction between double-bond functionalized TiO2 nanoparticles and styrene. PSVT showed an excellent bilirubin adsorption ability and antibacterial performance, ensuring efficient clearance of bilirubin in liver failure patients during hemoperfusion and preventing bacterial infection. The experimental results indicated that TiO2 was uniformly dispersed in the microspheres, which improved the mesoporous structure and increased the specific surface area. Composite adsorbent PSVT showed an exceptional bilirubin adsorption capacity, with the maximum adsorption capacity reaching 24.3 mg/g. In addition, the introduction of TiO2 endowed PSVT with excellent antibacterial ability; the ultimate antibacterial rates against Escherichia coli and Staphylococcus aureus reached 97.31 and 96.47%, respectively. In summary, PSVT served as a novel antibacterial bilirubin adsorbent with excellent bilirubin clearance capacity and antibacterial performance, providing excellent application prospects for treating liver failure patients.

The Impact of Solution Ionic Strength, Hardness, and pH on the Sorption Efficiency of Polychlorinated Biphenyls in Magnetic Nanocomposite Microparticle (MNM) Gels

Environmental conditions of groundwater and surface water greatly vary as a function of location. Factors such as ionic strength, water hardness, and solution pH can change the physical and chemical properties of the nanocomposites used in remediation and the pollutants of interest. In this work, magnetic nanocomposite microparticle (MNM) gels are used as sorbents for remediation of PCB 126 as model organic contaminant. Three MNM systems are used: curcumin multiacrylate MNMs (CMA MNMs), quercetin multiacrylate MNMs (QMA MNMs), and polyethylene glycol-400-dimethacrylate MNMs (PEG MNMs). The effect of ionic strength, water hardness, and pH were studied on the sorption efficiency of the MNMs for PCB 126 by performing equilibrium binding studies. It is seen that the ionic strength and water hardness have a minimal effect on the MNM gel system sorption of PCB 126. However, a decrease in binding was observed when the pH increased from 6.5 to 8.5, attributed to anion-π interactions between the buffer ions in solution and the PCB molecules as well as with the aromatic rings of the MNM gel systems. Overall, the results indicate that the developed MNM gels can be used as magnetic sorbents for polychlorinated biphenyls in groundwater and surface water remediation, provided that the solution pH is controlled.

Biocompatible Composite Microspheres of Chitin/Ordered Mesoporous Carbon CMK3 for Bilirubin Adsorption and Cell Microcarrier Culture

Extra bilirubin in the blood can provoke serious illness in patients with severe liver disease. Hemoperfusion is an effective method to remove the extra bilirubin, but its application is limited by the low adsorption efficiency and poor biocompatibility of available adsorbent materials. In this study, chitin/ordered mesoporous carbon CMK3 (Ch/CMK3) microspheres were successfully prepared. Results of characterization experiments indicated that these composite microspheres possess a multilayered porous nanofibrous structure with an extremely large specific surface area (300.19 m² g^-1 ) and large pore size. Notably, the Ch/CMK3 microspheres demonstrated a high bilirubin adsorption capacity (228.19 mg g^-1 ) in phosphate buffer solution, and an outstanding bilirubin removal ratio (76.78%±4.40%) in the plasma of rabbits with hyperbilirubinemia without affecting the protein components. More importantly, the Ch/CMK3 microspheres showed no effect on other blood components, no cytotoxicity, and no systemic toxicity to mice. Cell coculture experiments revealed that the microspheres could provide a three-dimensional (3D) space to promote cell adhesion, proliferation, and nutrient exchange. These Ch/CMK3 microspheres featuring a strong ability for bilirubin adsorption and good biocompatibility could be a promising candidate in biomedical applications such as hemoperfusion, cell microcarrier, and 3D tissue engineering. This article is protected by copyright. All rights reserved.

Hydroxyapatite reinforced inorganic-organic hybrid nanocomposite as high-performance adsorbents for bilirubin removal in vitro and in pig models

Highly efficient removal of bilirubin from whole blood directly by hemoperfusion for liver failure therapy remains a challenge in the clinical field due to the low adsorption capacity, poor mechanical strength and low biocompatibility of adsorbents. In this work, a new class of nanocomposite adsorbents was constructed through an inorganic-organic co-crosslinked nanocomposite network between vinyltriethoxysilane (VTES)-functionalized hydroxyapatite nanoparticles (V-Hap) and non-ionic styrene-divinylbenzene (PS-DVB) resins (PS-DVB/V-Hap) using suspension polymerization. Notably, our adsorbent demonstrated substantially improved mechanical performance compared to the pure polymer, with the hardness and modulus increasing by nearly 3 and 2.5 times, respectively. Moreover, due to the development of a mesoporous structure, the prepared PS-DVB/V-Hap3 exhibited an ideal adsorption capacity of 40.27 mg g-1. More importantly, the obtained adsorbent beads showed outstanding blood compatibility and biocompatibility. Furthermore, in vivo extracorporeal hemoperfusion verified the efficacy and biosafety of the adsorbent for directly removing bilirubin from whole blood in pig models, and this material could potentially prevent liver damage and improve clinical outcomes. Taken together, the results suggest that PS-DVB/V-Hap3 beads can be used in commercial adsorption columns to threat hyperbilirubinemia patients through hemoperfusion, thus replacing the existing techniques where plasma separation is initially required.

Adsorption of ibuprofen using cysteine-modified silane-coated magnetic nanomaterial

Industrialization and growth of the pharmaceutical companies have been a boon to the mankind in our day to day life in myriad ways. However, due to the uninhibited release of these active pharmaceutical compounds into the water systems has caused detrimental effects to the genetic pool. In this study, L-cysteine-modified 3-glycidyloxypropyltrimethoxysilane-coated magnetic nanomaterial showed a maximum removal of the efficiency of 82.90% for the nanomaterial dosage of 30 mg at an initial concentration of 50 mg L^-1 at pH 6.0. Further, the nanomaterial showed reusability efficiency up to 80% for three cycles. The adsorption kinetics follow the pseudo-second-order reaction and the adsorption isotherm model best fits the Langmuir isotherm proving the adsorption process to be a monolayer sorption on a monolayer surface. This magnetic nanomaterial could serve as a promising tool for the removal of pharmaceutical compounds from aqueous solutions. Graphical abstract ᅟ.

Selective adsorption of bilirubin against albumin to alkylamine functionalized PVA microspheres

Adsorbents are widely used in hemoperfusion for bilirubin removal. However, their performance is often compromised by the presence of plasma proteins. In this study, the bilirubin adsorption capacity of polyvinyl alcohol microspheres (PVAm) functionalized with different amino-alkane ligands has been investigated, with the aim of gaining binding selectivity over albumin. Octylamine-functionalized PVA microspheres (PVAm-8) exhibited an excellent adsorption capacity for bilirubin (75% and 3.95 mg/mL in PBS vs 72% and 3.84 mg/mL in albumin solution) when compared to the clinical adsorbent BPR (92% and 4.84 mg/mL in PBS vs 71%, and 3.80 mg/mL in albumin solution). The bilirubin adsorption capacities of PVAm-8 were largely unaffected by the presence of albumin. Adsorption of bilirubin to PVAm-8 occurs mainly through hydrophobic effects, with adsorption consistent with the monolayer model and the pseudo-first-order model operating in both PBS and albumin solution. The effects of PVAm-8 on hemolytic activity, blood component stability and coagulant activity were negligible, indicating that PVAm-8 has good potential as a high-affinity bilirubin adsorbent for hemoperfusion applications.

Bead-type polystyrene/nano-CaCO3 (PS/nCaCO3) composite: a high-performance adsorbent for the removal of interleukin-6

A novel nano-CaCO₃ (nCaCO₃) particle composite-derived polystyrene (PS) resin was successfully synthesized by a suspension polymerization method. The nCaCO₃ reinforced PS material (PS/nCaCO₃) possessed a structure with abundant mesopores of high porosity, high specific surface area (828.3 m² g^-1) and large pore volume (1.83 cm³ g^-1). It was revealed that the incorporation of nCaCO₃ into the PS matrix enhanced both the mechanical strength which can prevent the fragmentation and its adsorption capacity for interleukin-6 (IL-6, M_W = 24.0 kDa) from human plasma. The adsorption isotherm could be described by the Langmuir model and classified as S-3 type, showing an IL-6 uptake of up to 25.6 ng g^-1 at an equilibrium concentration of about 500 ng L^-1. The adsorption capacity for IL-6 of PS/nCaCO₃ is not only significantly higher than that of PS (without nCaCO₃), but also superior to those of currently available adsorbents that are under clinical studies (e.g., CytoSorb™ towards cytokines). In addition, the PS/nCaCO₃ adsorbent also had good hemocompatibility and showed no leakage of nCaCO₃ in the plasma in a flowing model system. Therefore, the synthesized PS/nCaCO₃ nano-composite has a great potential to be used as an efficient adsorbent for the removal of interleukin-6 (IL-6) from blood of inflammatory and auto-immune disease patients through hemoperfusion.

Recent advances on iron oxide magnetic nanoparticles as sorbents of organic pollutants in water and wastewater treatment

The constant growth in population worldwide over the past decades continues to put forward the need to provide access to safe, clean water to meet human needs. There is a need for cost-effective technologies for water and wastewater treatment that can meet the global demands and the rigorous water quality standards and at the same maximizing pollutant efficiency removal. Current remediation technologies have failed in keeping up with these factors without becoming cost-prohibitive. Most recently, nanotechnology has been sought as the best alternative to increase access to water supplies by remediating those already contaminated and offering ways to access unconventional sources. The use of iron oxide magnetic nanoparticles as nanoadsorbents has led way to a new class of magnetic separation strategies for water treatment. This review focuses on highlighting some of the most recent advances in core-shell iron oxide magnetic nanoparticles and nanocomposites containing iron oxide nanoparticles currently being developed for water and wastewater treatment of organic pollutants. We discuss the novelty of these novel materials and the insight gained from their advances that can help develop cost-effective reusable technologies for scale-up and commercial use.