Comparison on the performance of green and conventional magnetic chitosan-based composites in the removal of complex dyes: Synergetic effect, experimental and theoretical studies.

The presence of complex dyes, which possess four or more aromatic rings, is pervasive in environmental matrices. Nanomaterials offer a promising avenue for their removal. In this study, we synthesized novel magnetic nanocomposites comprising nanochitosan (nCS) and iron nanoparticles through the application of green and conventional protocols.

Antiviral effect of oversulfated kappa-carrageenan derivatives against COVID-19 for spray coating application on facemasks.

The COVID-19 pandemic caused by SARS-CoV-2 has spurred the urgent need for effective antiviral strategies. In this work, we explored the potential of oversulfated kappa-carrageenan (OSKC) in spray-coated facemasks for SARS-CoV-2 inhibition pathway. The sulfated derivative was synthesized with sulfur trioxide pyridine complex in dimethylformamide solution.

Development of quaternized agar-based materials for the coronavirus inactivation.

The COVID-19 pandemic has revealed weaknesses in healthcare systems and underscored the need for advanced antimicrobial materials. This study investigates the quaternization of agar, a seaweed-derived polysaccharide, and the development of electrospun membranes for air filtration in facemasks and biomedical applications. Using the betacoronavirus MHV-3 as a model, quaternized agar and membranes achieved a 90-99.

Adsorption and ion exchange of toxic metals by Brazilian clays: clay selection and studies of equilibrium, thermodynamics, and binary ion exchange modeling.

In this study, four Brazilian clays (Bofe, Verde-lodo, commercial Fluidgel, and expanded commercial vermiculite) were evaluated for their adsorptive capacity and removal percentage in relation to different toxic metals (Ni, Cd, Zn, and Cu). The best results were obtained by expanded vermiculite, with cadmium removal reaching values of 95%. The most promising clay was modified by the sodification process, and the metal cadmium was used to evaluate the ion exchange process.

Exploiting in silico modelling to enhance translation of liver cell therapies from bench to bedside.

Cell therapies are emerging as promising treatments for a range of liver diseases but translational bottlenecks still remain including: securing and assessing the safe and effective delivery of cells to the disease site; ensuring successful cell engraftment and function; and preventing immunogenic responses. Here we highlight three therapies, each utilising a different cell type, at different stages in their clinical translation journey: transplantation of multipotent mesenchymal stromal/signalling cells, hepatocytes and macrophages. To overcome bottlenecks impeding clinical progression, we advocate for wider use of mechanistic in silico modelling approaches.

Self-assembly mucoadhesive beads of κ-carrageenan/sericin for indomethacin oral extended release.

Oral drug administration, especially when composed of mucoadhesive delivery systems, has been a research trend due to increased residence time and contact with the mucosa, potentially increasing drug bioavailability and stability. In this context, this study aimed to develop self-assembly mucoadhesive beads composed of blends of κ-carrageenan and sericin (κ-Car/Ser) loaded with the anti-inflammatory drug indomethacin (IND). We investigated the swelling, adhesion behaviour, and mechanical/physical properties of the beads, assessing their effects on cell viability, safety and permeation characteristics in both 2D and triple-culture model.

Enhanced degradation and removal of ciprofloxacin and ofloxacin through advanced oxidation and adsorption processes using environmentally friendly modified carbon nanotubes.

This study explores the utilization of adsorption and advanced oxidation processes for the degradation of ofloxacin (OFL) and ciprofloxacin (CIP) using a green functionalized carbon nanotube (MWCNT-OH/COOH-E) as adsorbent and catalyst material. The stability and catalytic activity of the solid material were proved by FT-IR and TG/DTG, which also helped to elucidate the reaction mechanisms. In adsorption kinetic studies, both antibiotics showed similar behavior, with an equilibrium at 30 min and 60% removal.

Green synthesis of carbon nanotubes functionalized with iron nanoparticles and coffee husk biomass for efficient removal of losartan and diclofenac: Adsorption kinetics and ANN modeling studies.

The presence of emerging contaminants in wastewater poses a global environmental challenge, requiring the development of innovative materials or methods for their treatment. This study focused on the production of green functionalized carbon nanotubes (CNTs) and using them in the adsorption of the pharmaceuticals Losartan (LOS) and Diclofenac (DIC). The efficiency of the methodology was verified by characterization techniques.

Pirarucu hydroxyapatite applied to ternary competitive adsorption of synthetic basic dyes as contaminants of emerging concern: kinetic, equilibrium, and ANN studies.

This study investigated the single and multicomponent adsorption of three emerging pollutants, the basic dyes Rhodamine 6G (R6G), Auramine-O (AO), and Brilliant Green (BG) by using hydroxyapatite synthesized from Pirarucu scales as adsorbent (HAP). The adsorption process was studied using seven different systems: AO-single, R6G-single, BG-single, R6G + AO, BG + AO, BG + R6G, and R6G + AO + BG. For kinetics, the initial concentration of each adsorbate per system was 50 mg/L, the results showed that the singular adsorption of these dyes was best-represented by the pseudo-second-order model (q = 62.

Visible-light photoactivated proanthocyanidin and kappa-carrageenan coating with anti-adhesive properties against clinically relevant bacteria.

The increase of bacterial resistance to antibiotics is a growing concern worldwide and the search for new therapies could cost billions of dollars and countless lives. Inert surfaces are major sources of contamination due to easier adhesion and formation of bacterial biofilms, hindering the disinfection process. Therefore, the objective of this study was to develop a photoactivatable and anti-adhesive kappa-carrageenan coating using proanthocyanidin as a photosensitizer.

κ-Carrageenan/sericin polymer matrix modified with different crosslinking agents and thermal crosslinking: Improved release profile of mefenamic acid.

The crosslinking of the polymer matrix with compatible macromolecules results in a three-dimensional network structure that offers an enhancement in the controlled release properties of the material. In this sense, this work aimed to improve the release profile of mefenamic acid (MAC) through crosslinking strategies. κ-Carrageenan/sericin crosslinked blend was obtained by covalent and thermal crosslinking and the different formulations were characterized.

Adsorption of contaminants by nanomaterials synthesized by green and conventional routes: a critical review.

Nanomaterials, due to their large surface area and selectivity, have stood out as an alternative for the adsorption of contaminants from water and effluents. Synthesized from green or traditional protocols, the main advantages and disadvantages of green nanomaterials are the elimination of the use of toxic chemicals and difficulty of reproducing the preparation of nanomaterials, respectively, while traditional nanomaterials have the main advantage of being able to prepare nanomaterials with well-defined morphological properties and the disadvantage of using potentially toxic chemicals. Thus, based on the particularities of green and conventional nanomaterials, this review aims to fill a gap in the literature on the comparison of the synthesis, morphology, and application of these nanomaterials in the adsorption of contaminants in water.

Fluoranthene adsorption by graphene oxide and magnetic chitosan composite (mCS/GO).

The oil industry faces the challenge of reducing its high polluting potential, due to the presence of aromatic pollutants, such as polycyclic aromatic hydrocarbons (PAHs). Efforts have been made to mitigate the impact of PAHs in industry through the development of detection technologies and the implementation of mitigation strategies. This study presents the adsorption of fluoranthene, through a magnetic composite of graphene oxide and chitosan as a method of remediation of produced water.

Biosorption of europium and erbium from aqueous solutions using crosslinked sericin-alginate beads.

Critical metals such as rare earths are essential for important industrial applications and for producing high-tech materials. Currently, the development of alternative and non-conventional biomaterials has gained significant interest. This work investigated the use of crosslinked sericin-alginate-based natural polymeric particles for the removal of rare earths from water.

Propranolol adsorption onto multiwalled carbon nanotubes modified by green synthesis: pH, kinetic, and equilibrium studies.

This research investigated the adsorption of propranolol (PROP) by functionalized green carbon nanotubes (MWCNT-B), assessing the influence of pH, in addition to kinetic, equilibrium, and thermodynamic studies and reuse of the material. For this purpose, speciation of PROP and the point of zero charge (pH) of MWCNT-B were performed, indicating a pKa of 9.67 and pH of 3.

Multi-pollutant biosorption of organic and inorganic pollutants by brown algae waste from alginate production: batch and fixed-bed investigation.

The reuse of biomass waste has been gaining attention in adsorption processes to remove pollutants of emerging concern from water and wastewater. In this work, the potential of alginate-extracted macro-algae waste to uptake synthetic dyes and metal cations was evaluated in comparison with raw algae. In affinity assays, both materials were able to remove metal cations and cationic dyes up to maximum rates, and no significant removal was observed for an anionic dye in an acidic medium.

Carbonaceous adsorbent as green silica by-product applied to the treatment of contaminated effluent by pesticide commonly sprayed on rice cultivation.

Grain cultivation and its impacts on the environment have been the focus of many studies, especially due to generated solid waste and the wide use of agrochemicals aiming for greater productivity. In this context, the present study proposes a new and consistent step in constructing self-sustainability in rice farming. The proposed stage includes reusing green silica waste as an adsorbent to treat effluents contaminated by pesticides directly applied to rice cultivation.

Development and characterization of crosslinked k-carrageenan/sericin blend with covalent agents or thermal crosslink for indomethacin extended release.

Modified release of multiparticulate pharmaceutical forms is a key therapeutic strategy to reduce side effects and toxicity caused by high and repeated doses of immediate-release oral drugs. This research focused on the encapsulation of indomethacin (IND) in the crosslinked k-Car/Ser polymeric matrix by covalent and thermal methods to evaluate drug delivery modulation and properties of the crosslinked blend. Therefore, the entrapment efficiency (EE %), drug loading (DL %) and physicochemical properties of the particles were investigated.

Adsorption kinetics of ciprofloxacin and ofloxacin by green-modified carbon nanotubes.

This paper investigated the uptake of CIP and OFL in single and multicomponent adsorptive systems using modified carbon nanotubes (CNTs) as adsorbent material. The characterization analyses of the pre- and post-process material by XPS, TG/DTG, FT-IR, SEM/EDS, and XRD helped in the elucidation of the mechanisms, indicating greater involvement of n-n and π -π interactions. In the kinetic studies, the simple systems with CIP and OFL were similar, both showed equilibrium time around 20/30 min and increased adsorptive capacity with increasing initial drug concentration.

Cerium biosorption onto alginate/vermiculite-based particles functionalized with ionic imprinting: Kinetics, equilibrium, thermodynamic, and reuse studies.

Cerium is an essential element for several applications in industry, therefore, recovering it from secondary sources is a promising strategy from an economic and environmental perspective. For this purpose, biosorption is a low-cost and effective alternative. The present work evaluated the recovery of Ce from aqueous solutions using alginate/vermiculite-based particles (ALEV) functionalized by ionic imprinting.

Amazon raw clay as a precursor of a clay-based adsorbent: experimental study and DFT analysis for the adsorption of Basic Yellow 2 dye.

A clay-based adsorbent (CBA) was purified from a sustainable precursor (raw clay, RC), which was obtained from the Amazon region in Brazil. The CBA was characterized using X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), Brunauer-Emmet-Teller surface area (S, RC = 23.386 m.

Comparative effect of mesoporous carbon doping on the adsorption of pharmaceutical drugs in water: Theoretical calculations and mechanism study.

In this study, mesoporous doped-carbons were synthesized from sucrose, a natural source, boric acid and cyanamide as precursors, generating B- or N-doped carbon. These materials were characterized by FTIR, XRD, TGA, Raman, SEM, TEM, BET, and XPS, confirming the preparation of a tridimensional doped porous structure. B-MPC and N-MPC showed a high surface specific area above 1000 m/g.

Hybrid process of adsorption and electrochemically based green regeneration of bentonite clay for ofloxacin and ciprofloxacin removal.

Removal of emerging contaminants, such as antibiotics, from wastewater by adsorption is a simple, low-cost, and high-performance process; however, regeneration and reuse of the exhausted adsorbent are necessary to make the process economically viable. This study aimed to investigate the possibility of electrochemical-based regeneration of clay-type materials. For this, the calcined Verde-lodo (CVL) clay was saturated with the antibiotics ofloxacin (OFL) and ciprofloxacin (CIP) in one-component systems by an adsorption process and then subjected to photo-assisted electrochemical oxidation (0.

Optimization of kappa-carrageenan cationization using experimental design for model-drug release and investigation of biological properties.

Cationization is a promising chemical modification technique that improves properties by attaching permanent positive charges to the backbone of biopolymers. Carrageenan is a widely available and non-toxic polysaccharide, commonly used in food industry but with low solubility in cold water. We performed a central composite design experiment to check the parameters that most influence the degree of cationic substitution and the film solubility.

k-Carrageenan/sericin-based multiparticulate systems: A novel gastro-resistant polymer matrix for indomethacin delivery.

This study aimed to develop a natural and multiparticulate carrier of k-carrageenan (k-Car) and sericin (Ser) for encapsulation of indomethacin (IND) in order to minimize gastrointestinal effects caused by immediate-release. Increasing the amount of IND in the formulations subtly reduced the entrapment efficiency (EE) and drug loading (DL) due to matrix saturation. Sericin was essential to improve EE and DL when compared to pure k-Car (EE > 90 % and DL > 47 %) with suitable particle sizes (1.