Novel Sodium Alginate/Polyvinylpyrrolidone/TiO2 Nanocomposite for Efficient Removal of Cationic Dye from Aqueous Solution

The combination of adsorption and photodegradation processes is an effective technique for the removal of dye contaminants from water, which is motivating the development of novel adsorbent-photocatalyst materials for wastewater treatment. Herein, novel nanocomposite porous beads were developed using titanium dioxide (TiO2) nanotubes embedded in a sodium alginate (SA)/polyvinylpyrrolidone (PVP) matrix using calcium chloride solution as a crosslinker. The prepared nanocomposite beads’ performance was examined as an adsorbent-photocatalyst for the breakdown of methylene blue in aqueous solutions. Several operation factors influencing the dye decomposition process, including photocatalyst dosage, illumination time, light intensity, and stability were investigated. The findings demonstrated that the removal activity of the beads changed with the TiO2 weight ratio in the composite. It was found that SA/PVP/TiO2-3 nanocomposite beads presented the greatest deterioration efficiency for methylene blue dye (98.9%). The cycling ability and reusability of the prepared SA/PVP/TiO2 nanocomposite beads recommend their use as efficient, eco-friendly materials for the treatment of wastewaters contaminated with cationic dyes.

Dual size-exclusion chromatography for efficient isolation of extracellular vesicles from bone marrow derived human plasma

Isolation of pure extracellular vesicles (EVs), especially from blood, has been a major challenge in the field of EV research. The presence of lipoproteins and soluble proteins often hinders the isolation of high purity EVs upon utilization of conventional separation methods. To circumvent such problems, we designed a single-step dual size-exclusion chromatography (dSEC) column for effective isolation of highly pure EVs from bone marrow derived human plasma. With an aim to select appropriate column design parameters, we analyzed the physiochemical properties of the major substances in bone marrow derived plasma, which include EVs, lipoproteins, and soluble proteins. Based on these findings, we devised a novel dSEC column with two different types of porous beads sequentially stacked each other for efficient separation of EVs from other contaminants. The newly developed dSEC columns exhibited better performance in isolating highly pure EVs from AML plasma in comparison to conventional isolation methods.

Synthesis And Characterization Of Alginate-Cellulose Xanthate Beads From Corn Stalk With NaCL As Porogen

In this study, the synthesis of porous beads from corn stalks was carried out. The cellulose extracted from corn stalks was converted into cellulose xanthate and combined with alginate to form porous alginate-cellulose xanthate beads by the ionic gelation method. This study attempted to use sodium chloride (NaCl) as a porogen and zinc acetate as a crosslinker. Beads were characterized to determine the porosity, swelling properties, and functional groups using Fourier Transform Infra-Red (FTIR). The geometry of beads was analyzed by optical microscopy, and its surface morphology was analyzed by Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX). The results showed that corn stalks as agricultural waste material could be used to synthesize porous beads material. The swelling and porosity of beads increased with increasing concentration of NaCl. The presence of porogen has increased beads formation. The results demonstrate the crosslinks between zinc acetate and alginate were successfully characterized using FTIR. NaCl concentration of 9.5% resulted in the highest swelling properties (52.80%) and porosity (81.4%) of the beads.