Tailoring of Mesoporous Silica-Based Materials for Enhanced Water Pollutants Removal

Optimization of adsorption performance by mesoporous materials developed from local clays and zeolite. Application in the treatment of real pharmaceutical effluents

The treatment of effluents from the pharmaceutical industry currently remains a major challenge due to their impact on the environment and public health along with the cost of treatments. Considering these issues, our work focused on the development of materials with effective adsorption properties to treat industrial effluents based on locally available and inexpensive clays and zeolite. Local Algerian kaolin (Djebel Debbagh), palygorskite (Ghoufi) and zeolite (Tinbdar) were treated thermally and chemically prior to synthesis into mesoporous materials of hexagonal structure using pluronic P123 as surfactant. The raw and synthesized materials were tested in the adsorption of pharmaceutical effluents from industries producing antihistamine and diuretic-type drugs. Analyses of physicochemical parameters (chemical and biological oxygen demand) as well as measurement of the concentrations of PO4³-, NO2-, NH4+ of effluents were done before and after the adsorption process by the raw and mesoporous clays and zeolite. The results showed a reduction of all parameters with greater efficiency of mesoporous DD3 which indicated that it is a promising mesoporous adsorbent for treating pharmaceutical effluents. Reduced rates of these three physical parameters (PO4³-, NO2-, NH4+) in the case of NEUROVIT® by mesoporous DD3 are 61%, 98% and 77%. However, PO4³-, NO2- elimination percentages DIAPHAG® onto DD3 are 79% and 87%, respectively.

Rapid and enhanced detection of sulfonamide antibiotic using task-specific ionic liquids nanoconfined in tunable nanoporous carbons

The development of a novel multifunctional adsorbent for the sensitive detection and capture of antibiotic residues in environmental and food samples presents a significant challenge. In this study, we synthesized a pioneering nanocomposite, ILs@PC, by encapsulating task-specific ionic liquids (ILs) within nitrogen-doped porous carbon (PC) derived from metal-triazolate frameworks. This ILs@PC nanocomposite functions as a multifunctional adsorbent in dispersive solid-phase extraction (DSPE), enabling simultaneous sorptive removal, sensitive detection, and molecular sieve selection. The ILs@PC demonstrated enhanced adsorption efficiency and sensitivity for sulfonamide antibiotics (SAs) compared to the pristine PC, attributed to the nanoconfinement effect of the ILs and the influence of pore volume on this effect. When integrated with high-performance liquid chromatography (HPLC), the ILs@PC-based DSPE method achieved a detection limit of 0.75-1.88 μg L-1 for SAs, along with satisfactory recoveries of 86.0 %-111.9 %. Additionally, a portable syringe device was developed to facilitate rapid on-site extraction and enrichment of SAs. The practicality of this method was validated through its successful application in detecting SAs in real samples, including lake water and milk. This approach highlights its potential for efficient and rapid monitoring of antibiotic residues in both environmental and food systems.

Nanoparticle-Based Drug Delivery Systems Enhance Treatment of Cognitive Defects

Nanoparticle-based drug delivery presents a promising solution in enhancing therapies for neurological diseases, particularly cognitive impairment. These nanoparticles address challenges related to the physicochemical profiles of drugs that hinder their delivery to the central nervous system (CNS). Benefits include improved solubility due to particle size reduction, enhanced drug penetration across the blood-brain barrier (BBB), and sustained release mechanisms suitable for long-term therapy. Successful application of nanoparticle delivery systems requires careful consideration of their characteristics tailored for CNS delivery, encompassing particle size and distribution, surface charge and morphology, loading capacity, and drug release kinetics. Literature review reveals three main types of nanoparticles developed for cognitive function enhancement: polymeric nanoparticles, lipid-based nanoparticles, and metallic or inorganic nanoparticles. Each type and its production methods possess distinct advantages and limitations. Further modifications such as coating agents or ligand conjugation have been explored to enhance their brain cell uptake. Evidence supporting their development shows improved efficacy outcomes, evidenced by enhanced cognitive function assessments, modulation of pro-oxidant markers, and anti-inflammatory activities. Despite these advancements, clinical trials validating the efficacy of nanoparticle systems in treating cognitive defects are lacking. Therefore, these findings underscore the need for researchers to expedite clinical testing to provide robust evidence of the potential of nanoparticle-based drug delivery systems.

Charge as a key physicochemical factor in adsorption of organic micropollutants from wastewater effluent by rice husk bio-silica

Wastewater treatment plants (WWTPs) often fail to fully remove organic micro-pollutants (OMPs), necessitating advanced treatment methods. This study examines the potential of an agricultural waste-derived adsorbent, rice husk (RH) - silica, for removing a complex mixture of 20 OMPs in MilliQ water and wastewater effluent. While RH-silica shows potential for OMP removal, its performance with multicomponent mixtures in real wastewater has yet to be investigated. Batch experiments demonstrated the efficacy of RH-silica in removing cationic, neutral, polar, and non-polar OMPs across various pH levels, with no adsorption of anionic OMPs. Column elution studies revealed that only positively charged compounds did not reach a breakthrough after 300 specific bed volumes (BVs), even when the filtration velocity was increased fivefold (3.8 m/h) and lower adsorbent-to-volume ratios (0.5 g/L) were employed. This indicates that electrostatic interactions via deprotonated silanol groups are the primary adsorption mechanism. RH-silica's ability to retain cationic pollutants regardless of their hydrophilicity degree highlights its potential as a novel adsorbent targeting positively charged persistent and mobile organic compounds (PMOCs). Moreover, the adsorption efficiency remained high in experiments with real wastewater effluent. Considering practical applications, a RH-silica column could be used to enhance removal of cationic polar compounds. This approach not only improves pollutant removal efficiency but also contributes to sustainability in WWTPs by using agricultural waste resources. Despite significant operational and end-of-life challenges for large-scale implementation, this study represents a crucial advancement in the investigation of RH-silica as an adsorbent.

Application of Mesoporous Silicas for Adsorption of Organic and Inorganic Pollutants from Rainwater

Precipitation is an important factor that influences the quality of surface water in many regions of the world. The pollution of stormwater runoff from roads and parking lots is an understudied area in water quality research. Therefore, a comprehensive analysis of the physicochemical properties of rainwater flowing from parking lots was carried out, considering heavy metals and organic micropollutants. High concentrations of zinc were observed in rainwater, in addition to alkanes, e.g., tetradecane, hexadecane, octadecane, 2,6,10-trimethyldodecane, 2-methyldodecane; phenolic derivatives, such as 2,6-dimethoxyphenol and 2,4-di-tertbutylphenol; and compounds such as benzothiazole. To remove the contaminants present in rainwater, adsorption using silica carriers of the MCF (Mesostructured Cellular Foams) type was performed. Three groups of modified carriers were prepared, i.e., (1) SH (thiol), (2) NH2 (amino), and (3) NH2/SH (amine and thiol functional groups). The research problem, which is addressed in the presented article, is concerned with the silica carrier influence of the functional group on the adsorption efficiency of micropollutants. The study included an evaluation of the effects of adsorption dose and time on the efficiency of the contaminant removal process, as well as an analysis of adsorption isotherms and reaction kinetics. The colour adsorption from rainwater was 94-95% for MCF-NH2 and MCF-NH2/SH. Zinc adsorbance was at a level of 90% for MCF-NH2, and for MCF-NH2/SH, 52%. Studies have shown the high efficacy (100%) of MCF-NH2 in removing organic micropollutants, especially phenolic compounds and benzothiazole. On the other hand, octadecane was the least susceptible to adsorption in each case. It was found that the highest efficiency of removal of organic micropollutants and zinc ions was obtained through the use of functionalized silica NH2.

Porphyrin-Based Hybrid Nanohelices: Cooperative Effect between Molecular and Supramolecular Chirality on Amplified Optical Activity

The development of chiral receptors for discriminating the configuration of the analyte of interest is increasingly urgent in view of monitoring pollution in water and waste liquids. Here, we investigate an easy protocol to immobilize the desired non-water-soluble receptors inside a water-dispersible chiral nanoplatform made of silica. This approach induces chirality in the receptors and Here, we investigate an easy protocol to immobilize the desired non-water-soluble receptors inside a water-dispersible chiral nanoplatform made of silica. This approach induces chirality in the receptors and makes the dye@nanohelix system disperse in a suspension of water without aggregation. We noted strong induction and amplification of chiroptical activity in both achiral and chiral (proline-based or hemicucurbituril-based) porphyrin derivatives with and without zinc ions once confined and organized in nanometer silica helices. The results clearly demonstrated that the organization-induced chirality amplification of porphyrins dominates the molecular chirality, and the amplification is more efficient for more flexible porphyrins (especially free-base and achiral).

On-line extraction and determination of coumarins compounds from mouse plasma based on a homemade phenyl-hybrid monolithic adsorbent

A phenyl-hybrid monolithic adsorbent was prepared using an organic monomer of ethylene glycol phenyl ether acrylate and inorganic monomers of tetramethoxysilane and vinyltrimethoxysilane, via polycondensation and polymerization in a stainless-steel column, which shows porous structure and multiple functional groups, according to the measurements of scanning electron microscopy, nitrogen adsorption-desorption method and infrared spectroscopy. The resulting hybrid phenyl-based monolith was used as a solid-phase extraction column, combining with an analytical column in conjunction with high-performance liquid chromatography system for the on-line extraction and determination of coumarins (praeruptorin A and praeruptorin B) in Peucedani Radix from mouse plasma. The homemade hybrid monolithic solid-phase extraction column exhibits good removal ability for the sample matrices, as well as unique selectivity for the two praeruptorins. Methodology validation results indicate that the present method is applicable for the on-line extraction and quantitative analysis of praeruptorin A and praeruptorin B in Peucedani Radix from mouse plasma with a limit of quantitation 0.06 μg/mL and a linear range 0.06-5 μg/mL (r＞0.999), thus indicating the present method is a promising and alternative method for the quantitative determination of similar target components with micro or trace concentration from complex extract solution and plasma.

Mesoporous Materials for Metal-Laden Wastewater Treatment

Rapid technological, industrial and agricultural development has resulted in the release of large volumes of pollutants, including metal ions, into the environment. Heavy metals have become of great concern due to their toxicity, persistence, and adverse effects caused to the environment and population. In this regard, municipal and industrial effluents should be thoroughly treated before being discharged into natural water or used for irrigation. The physical, chemical, and biological techniques applied for wastewater treatment adsorption have a special place in enabling effective pollutant removal. Currently, plenty of adsorbents of different origins are applied for the treatment of metal-containing aqueous solution and wastewater. The present review is focused on mesoporous materials. In particular, the recent achievements in mesoporous materials' synthesis and application in wastewater treatment are discussed. The mechanisms of metal adsorption onto mesoporous materials are highlighted and examples of their multiple uses for metal removal are presented. The information contained in the review can be used by researchers and environmental engineers involved in the development of new adsorbents and the improvement of wastewater treatment technologies.