Recent occurrence of pharmaceuticals in freshwater, emerging treatment technologies, and future considerations: A review

Pharmaceuticals represent an emerging class of pollutants raising significant environmental health concerns, with their presence in freshwater systems linked to adverse aquatic ecosystem impacts and acceleration of antibiotic resistance development. This narrative review examines recent (2019–2024) pharmaceutical occurrences in freshwater globally, analyzes contamination pathways, evaluates compound-specific degradability, and assesses treatment technologies. Analysis revealed significant pharmaceutical contamination in freshwater sources across the six major continents, primarily entering through wastewater treatment plant effluents, groundwater recharge processes, and inadequate sanitation infrastructure/septic systems. Stark geographical disparities were observed, with regions lacking centralized treatment infrastructure showing multiple-fold higher concentrations, particularly in Africa and Latin America (exemplified by amoxicillin levels reaching 272,156 ng/L in Lagos, Nigeria). Pharmaceutical profiles reflected local healthcare patterns, with antimalarials and antiretrovirals prevalent in endemic regions. Globally prevalent compounds included caffeine, acetaminophen, ibuprofen, carbamazepine, sulfamethoxazole, amoxicillin, and diclofenac. While some compounds like caffeine showed relatively good removal in conventional treatment systems, their high usage rates overwhelmed treatment capacity. Others, particularly carbamazepine, demonstrated high recalcitrance to conventional treatment methods. Advanced oxidation processes and membrane technologies showed high removal efficiencies, while biochar-based systems emerged as promising, cost-effective alternatives using locally available resources. The findings underscore the need for both centralized and decentralized treatment approaches. Point-of-use technologies emerge as crucial immediate interventions for regions with inadequate infrastructure, while advanced technologies show promise for large-scale applications. The review emphasizes that municipalities should conduct systematic screening to identify locally prevalent pharmaceuticals, as treatment requirements vary significantly with local usage patterns, making a one-size-fits-all approach ineffective

Beyond Covalent Crosslinks: Applications of Supramolecular Gels

Traditionally, gels have been defined by their covalently cross-linked polymer networks. Supramolecular gels challenge this framework by relying on non-covalent interactions for self-organization into hierarchical structures. This class of materials offers a variety of novel and exciting potential applications. This review draws together recent advances in supramolecular gels with an emphasis on their proposed uses as optoelectronic, energy, biomedical, and biological materials. Additional special topics reviewed include environmental remediation, participation in synthesis procedures, and other industrial uses. The examples presented here demonstrate unique benefits of supramolecular gels, including tunability, processability, and self-healing capability, enabling a new approach to solve engineering challenges. Keywords: supramolecular gel; self-assembly; gels; applied soft matte

Solar Degradation of Sulfamethazine Using rGO/Bi Composite Photocatalysts

This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness and by FEDER (CTQ2016-80978-C2−1-R), and the authors thank to Dr. Isabel Guerra Tschuschke for the technical advice during the VP-SEM study at the CIC-UGR.Heterogeneous photocatalysts for water decontamination were obtained by the optimized synthesis of bismuth-functionalized reduced graphene oxide (rGO/Bi) using the Hummer method and microwave treatment. Sulfamethazine (SMZ) was used as model pollutant to evaluate the photocatalytic efficacy. Photocatalysts were characterized by VP-SEM, HRTEM, XDR, XPS, RAMAN, and FTIR analyses, which confirmed the effective reduction of GO to rGO and the presence of bismuth as a crystalline phase of Bi2O3 polydispersed on the surface. Their performance was influenced by the rGO/Bi ratio, microwave temperature, and treatment time. The as-obtained 5%rGO/Bi composite had the highest photocatalytic activity for SMZ degradation under visible light irradiation (λ > 400 nm), achieving 100% degradation after only 2 h of treatment. The degradation yield decreased with higher percentages of rGO. Accordingly, the rGO/Bi catalysts efficiently removed SMZ, showing a high photocatalytic activity, and remained unchanged after three treatment cycles; furthermore, cytotoxicity tests demonstrated the nontoxicity of the aqueous medium after SMZ degradation. These findings support the potential value of these novel composites as photocatalysts to selectively remove pollutants in water treatment plants.Spanish Ministry of Economy, Industry and Competitiveness CTQ2016-80978-C2-1-REuropean Union (EU) CTQ2016-80978-C2-1-

Wastewater Treatment: Current and Future Techniques

This book examines the state-of-the-art water and wastewater treatment methods that can be applied to develop a sustainable treatment technique in the future. Of the several high-quality articles submitted, twelve were published after the peer-review process, with an acceptance rate of 59 percent. In the first section of this book, the articles include the occurrence and removal of emerging contaminants in water bodies. Moreover, the presence of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in water sources is discussed in detail. Subsequently, the removal of polycyclic aromatic hydrocarbons (PAHs), pharmaceuticals and personal care products (PPCPs), and dye with different physicochemical methods is investigated. In another section of this book, the removal of ammonia with anaerobic ammonium oxidation (anammox) is studied. Additionally, the elimination of heavy metals using the adsorption process, as an effective method, is discussed. Moreover, the performance of membrane bioreactors in the elimination of pollutants from landfill leachate is investigated in another article in this book. In addition to this, green and sustainable wastewater technologies (GSWTs) have recently attracted the attention of researchers. Therefore, nanoremediation and microalgae-based systems are discussed as the GSWTs

Recent occurrence of pharmaceuticals in freshwater, emerging treatment technologies, and future considerations: A review

Pharmaceuticals represent an emerging class of pollutants raising significant environmental health concerns, with their presence in freshwater systems linked to adverse aquatic ecosystem impacts and acceleration of antibiotic resistance development. This narrative review examines recent (2019–2024) pharmaceutical occurrences in freshwater globally, analyzes contamination pathways, evaluates compound-specific degradability, and assesses treatment technologies. Analysis revealed significant pharmaceutical contamination in freshwater sources across the six major continents, primarily entering through wastewater treatment plant effluents, groundwater recharge processes, and inadequate sanitation infrastructure/septic systems. Stark geographical disparities were observed, with regions lacking centralized treatment infrastructure showing multiple-fold higher concentrations, particularly in Africa and Latin America (exemplified by amoxicillin levels reaching 272,156 ng/L in Lagos, Nigeria). Pharmaceutical profiles reflected local healthcare patterns, with antimalarials and antiretrovirals prevalent in endemic regions. Globally prevalent compounds included caffeine, acetaminophen, ibuprofen, carbamazepine, sulfamethoxazole, amoxicillin, and diclofenac. While some compounds like caffeine showed relatively good removal in conventional treatment systems, their high usage rates overwhelmed treatment capacity. Others, particularly carbamazepine, demonstrated high recalcitrance to conventional treatment methods. Advanced oxidation processes and membrane technologies showed high removal efficiencies, while biochar-based systems emerged as promising, cost-effective alternatives using locally available resources. The findings underscore the need for both centralized and decentralized treatment approaches. Point-of-use technologies emerge as crucial immediate interventions for regions with inadequate infrastructure, while advanced technologies show promise for large-scale applications. The review emphasizes that municipalities should conduct systematic screening to identify locally prevalent pharmaceuticals, as treatment requirements vary significantly with local usage patterns, making a one-size-fits-all approach ineffective

Targeted Delivery of Insulin by Psyllium Plant (Plantago ispaghula) based hydrogels/membranes

Developments in therapeutics are the need of hour for the benefit of mankind and to increase the quality of life. Diabetes mellitus is a non-curable disease affecting a great amount of world’s population. This genetic disorder gets worse with time and ultimately leads to various complications like renal failure, lower limb amputation, heart diseases and blindness. Hydrogels for quite recent time are being used for the drug delivery. The present article is related to the fabrication of psyllium based dermal patches insulin drug delivery system that could release insulin in a sustained and controlled manner. Psyllium, a natural polysaccharide, is a medicinally important dietary fiber and drug delivery system has developed a novel insulin loaded psyllium based hydrogels for glucose lowering. They can be used for the transdermal delivery of insulin as hypodermic administration of insulin is painful, complicated, can also results in allergic reactions and infections. For the sustained and steady release of insulin from fabricated hydrogels were also modified with the addition of graphene oxide nanoparticles. To study the structural aspects of these various polymeric networks thus formed were characterized with FTIR (Fourier-transform infrared spectroscopy) and SEM (Scanning electron microscopy) which identifies the interaction/bonding among different functional groups and also indicating the layer of graphene oxide nanoparticles on the surface of hydrogels stage and release related experiments such as degradability, swelling kinetics, swelling ratio and drug kinetics were also performed. Because of its functionalization these unique 3D drug loaded polymeric hydrogels will have the double prospective of diabetes. Different types of psyllium based hydrogels were prepared, and the effect of ph on the release dynamics of insulin from drug loaded hydrogels has been studied to evaluate the drug release mechanism in-vitro and in-vivo. For in-vivo study avian skin was used a model. Fickian diffusion mechanism has been observed for the release of insulin at different ph both in and in-vivo and therefore these drug loaded hydrogels can be potentially used to develop pH-sensitive systems. Keeping in view the results of different analysis it can be concluded that these hydrogels can prove to be very useful for the treatment of diabetes mellitus

Pilot-scale adsorption of pharmaceuticals from municipal wastewater effluent using low-cost magnetite-pine bark: regeneration/enumeration of viable bacteria with a study on their biotoxicity

Abstract A low-cost and renewable magnetite-pine bark (MPB) sorbent was evaluated in continuous-flow systems for the removal of various pharmaceuticals from municipal wastewater effluent following membrane bioreactor (MBR) treatment. A 33-day small-scale column test (bed volume: 791 cm3) was conducted using duplicate columns of biochar (BC, Novocarbo) and activated carbon (AC, ColorSorb) as reference for two columns of BC and MPB in order to compare the efficiency of AC and MPB. After the small-scale column test, the pharmaceutical concentrations were generally below the detection limit. In the next stage, a four-month pilot-scale adsorption test was performed using a large column (bed volume: 21 L) filled with BC and MPB. A variety of compounds were removed after the pilot-scale column, including trimethoprim (99.7%), hydrochlorothiazide (81.8%), candesartan (26.0%), carbamazepine (86.1%), ketoprofen (89.4%), clindamycin (86.6%), oxazepam (91.3%), sulfadiazine (38.6%), sulfamethoxazole (58.3%), tramadol (88.9%), zopiclone (73.5%), venlafaxine (93.7%), furosemide (93.5%), fexofenadine (91.6%) and losartan (81.2%). The enumeration of viable bacteria in the pilot-scale column samples revealed that regenerating the BC-MPB bed with NaOH increased bacterial counts in the treated water due to the desorption of adsorbed bacteria from the bed. A biotoxicity study using the Nitrosomonas europaea bioreporter strain indicated that the wastewater was generally non-toxic to this nitrifying bacterium and regeneration of pilot-scale column samples caused short-time toxicity immediately after regeneration. The study confirms that MPB is efficient for the adsorption of pharmaceuticals and can be applied in column mode with a support material such as BC. Therefore, MPB is a viable alternative for AC for the remediation of pharmaceutical-contaminated wastewaters.Abstract A low-cost and renewable magnetite-pine bark (MPB) sorbent was evaluated in continuous-flow systems for the removal of various pharmaceuticals from municipal wastewater effluent following membrane bioreactor (MBR) treatment. A 33-day small-scale column test (bed volume: 791 cm3) was conducted using duplicate columns of biochar (BC, Novocarbo) and activated carbon (AC, ColorSorb) as reference for two columns of BC and MPB in order to compare the efficiency of AC and MPB. After the small-scale column test, the pharmaceutical concentrations were generally below the detection limit. In the next stage, a four-month pilot-scale adsorption test was performed using a large column (bed volume: 21 L) filled with BC and MPB. A variety of compounds were removed after the pilot-scale column, including trimethoprim (99.7%), hydrochlorothiazide (81.8%), candesartan (26.0%), carbamazepine (86.1%), ketoprofen (89.4%), clindamycin (86.6%), oxazepam (91.3%), sulfadiazine (38.6%), sulfamethoxazole (58.3%), tramadol (88.9%), zopiclone (73.5%), venlafaxine (93.7%), furosemide (93.5%), fexofenadine (91.6%) and losartan (81.2%). The enumeration of viable bacteria in the pilot-scale column samples revealed that regenerating the BC-MPB bed with NaOH increased bacterial counts in the treated water due to the desorption of adsorbed bacteria from the bed. A biotoxicity study using the Nitrosomonas europaea bioreporter strain indicated that the wastewater was generally non-toxic to this nitrifying bacterium and regeneration of pilot-scale column samples caused short-time toxicity immediately after regeneration. The study confirms that MPB is efficient for the adsorption of pharmaceuticals and can be applied in column mode with a support material such as BC. Therefore, MPB is a viable alternative for AC for the remediation of pharmaceutical-contaminated wastewaters

Current challenges for biological treatment of pharmaceutical-based contaminants with oxidoreductase enzymes: immobilization processes, real aqueous matrices and hybrid techniques

The worldwide access to pharmaceuticals and their continuous release into the environment have raised a serious global concern. Pharmaceuticals remain active even at low concentrations, therefore their occurrence in waterbodies may lead to successive deterioration of water quality with adverse impacts on the ecosystem and human health. To address this challenge, there is currently an evolving trend toward the search for effective methods to ensure efficient purification of both drinking water and wastewater. Biocatalytic transformation of pharmaceuticals using oxidoreductase enzymes, such as peroxidase and laccase, is a promising environmentally friendly solution for water treatment, where fungal species have been used as preferred producers due to their ligninolytic enzymatic systems. Enzyme-catalyzed degradation can transform micropollutants into more bioavailable or even innocuous products. Enzyme immobilization on a carrier generally increases its stability and catalytic performance, allowing its reuse, being a promising approach to ensure applicability to an industrial scale process. Moreover, coupling biocatalytic processes to other treatment technologies have been revealed to be an effective approach to achieve the complete removal of pharmaceuticals. This review updates the state-of-the-art of the application of oxidoreductases enzymes, namely laccase, to degrade pharmaceuticals from spiked water and real wastewater. Moreover, the advances concerning the techniques used for enzyme immobilization, the operation in bioreactors, the use of redox mediators, the application of hybrid techniques, as well as the discussion of transformation mechanisms and ending toxicity, are addressed.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, and by LABBELS – Associate Laboratory in Biotechnology, Bioengineering and Microelectromechnaical Systems, LA/P/0029/2020. Helena Sá thanks FCT for funding her PhD grant (UI/BD/151239/2021).info:eu-repo/semantics/publishedVersio

Near Infrared Electrogenerated Chemiluminescence and Related Electrochemical Properties of Gold Nanoclusters

This dissertation studies the fundamental principles and analysis applications of electrochemiluminescence (ECL) from atomically precise nanoclusters. The nanoclusters under study are composed of a metal core stabilized by a monolayer of covalently attached ligands. Chapter one describes the basics of ECL and an overview of gold nanoclusters including both fundamentals and applications. In chapter two, the kinetics of ECL generation are investigated where nanoclusters are either immobilized on the surface or free diffusing in solution. The ECL intensity-time profiles suggest that bimolecular or pseudo first order reactions limit the ECL generation immediately following the establishment of the applied potentials, while later ECL generation is governed by diffusion or mass transport displaying a Cottrell type decay over inverse square root time. Analytical equations are derived based on ECE reaction mechanism. Successful fitting to the experiments paves ways for generalized application. In chapter three, a ratiometric analysis strategy is developed based on the kinetics of charge transfer reactions. Absolute and ratiometric electrochemiluminescence signals are elucidated from single measurements for the detection of hydroxyzine and cetirizine as prototype drugs. The two compounds function as ECL coreactants to greatly enhance the near-infrared ECL from Au22(LA)12 NCs on ITO electrodes. The kinetic profiles as signals not only improve the signal/noise ratio but also offer greater resolving power to differentiate analogue species and nonspecific interference. These case studies successfully detected and identified drug compounds in the sub nanomolar physiological range and confirmed the effectiveness of point-of-care applications. The fundamental multi-point kinetics-based ratiometric concept/strategy is not limited to a specific ECL system and generalizable to other detection systems. In chapter four, the energy band gap at the nonmetallic to metallic transitions are revealed with Au133(TBBT)52, Au144(BM)60, and Au279(TBBT)84 (whereas TBBT is 4-tert-butylbenzenethiol and BM is benzyl mercaptan; abbreviated as Au133, Au144, and Au279). Electrochemical experiments resolve different energy gaps for Au133 and Au144 at room temperature, but not for Au279 which is metallic. Spectroelectrochemistry features of Au133 and Au144 are compared with ultrafast spectroscopy to demonstrate a generalizable analysis approach to correlate steady-state and transient spectrum features. Insights on the factors affecting the energy band gap and quantized double-layer capacitance will guide future studies on improving ECL and photoluminescence properties of metal nanoclusters

Uudsed eluendilisandid LC-MS baasil bioanalüütilistele metoodikatele

Väitekirja elektrooniline versioon ei sisalda publikatsiooneKäesoleva töö eesmärk oli laiendada teadmisi uudsete eluendilisandite kasutamiseks bioanalüütilises keemias kasutades vedelikkromatograafia-massispektromeetria (LC-MS) analüüsimeetodit. Nende kahe instrumendi: LC ja MS ühendamine laiendab määratavate analüütide hulka, kuigi seab ka piiranguid mobiilfaasi lenduvuse osas. Seejuures mitmed mittelenduvad eluendilisandid, mis aitavad suurendada LC analüüsi efektiivsust ja on küll laialdaselt kasutatud traditsiooniliste UV/Vis detektori puhul, kuid pole kasutatavad MS detektoritele. Uudsete fluoroalkoholide kasutamine eluendilisanditena võimaldab LC-MS analüüsile paljulubavat tulevikku. Fluoroalkoholid kui nõrgad happelised ühendid, millel on ioonpaaride moodustamise võimekus ja mis soodustavad analüütide ioniseerumist MS detekteerimisel, võimaldavad nii keerulistest segudest paremini komponente eraldada kui ka neid paremini detekteetida. Selleks, et uurida mõju ravimite retentsioonile pöördfaas-vedelikkromatograafias, testiti mitmeid paljulubavaid ühendeid aluselise pH juures. Lisandite uurimiseks kasutati erinevaid analüütilisi kolonne - C18, bifenüül ja pentafluorofenüül (PFP) ning uuriti mudel-analüütide ja üldlevinud ravimite ning narkootikumide käitumist. Töö raames leiti, et kasutatud fluoroalkoholid mõjutavad analüüsi vähendades happeliste analüütide retentsiooni ja suurendades aluseliste analüütide retentsiooni. Uudsed eluendilisandid rakendati ka kahes praktilises rakendusnäites. Esiteks kasutati neid uinutite morfiin, klonidiin ja midasolaam (ning nende metaboliitide) ülitundlikuks mõõtmiseks. Teiseks kasutati uudseid lisandeid südame- ja veresoonkonna ravimite milrinooni ja dobutamiini tundlikkuks mõõtmiseks. Neid kahte bioanalüütilist metoodikat kasutati ravimite ja metaboliitide mõõtmiseks laste vereplasmast farmakokineetiliste ja farmakodünaamiliste uuringute tarbeks. Uudsete eluendilisandite mõju analüütide ioniseerumisele võimaldas mõlema metoodikaga saavutada erakordselt madalaid määramispiire, vajades seejuures minimaalset proovikogust, mis oli sobilik just antud patsientide grupile.The aim of this thesis was to expand knowledge about novel eluent additives used in bioanalytical chemistry using liquid chromatography-mass spectrometry (LC-MS) analysis technique. The combination of the two instruments, an LC and MS expands the limits of analytes that can be detected and quantified. However, it also introduced considerable limitations in terms of mobile phase volatility. Thus, many eluent additives which helped to increase the efficiency of LC analysis and were widely used when UV/Vis was a detector did not pass the criteria anymore. However, a promising perspective in LC-MS analysis is offered by novel fluoroalcoholic eluent additives. They are weakly acidic compounds with ion-pairing capabilities and with a positive influence on analyte ionisation in the MS source. To research the influence on retention patterns of pharmaceuticals, several novel eluent additives were tested in the basic mobile phase pH range. Different analytical column stationary phases - C18, biphenyl and pentafluorphenyl (PFP) - were investigated, both with model analytes and a large set of common toxicology screening compounds. It was observed that the use of these fluoroalcohols influenced the analysis by decreasing retention of acidic analytes and increasing retention for analytes with basic properties. Two practical applications employing novel eluent additives were developed and validated for the pharmaceuticals morphine, clonidine, midazolam, and their metabolites, as well as, for milrinone and dobutamine. The two bioanalytical methods were used to obtain data for pharmacokinetic and pharmacodynamic studies in paediatric patients. Both methods reached exceptionally low limits of quantification, with minimal sample amount used due to the positive influence of novel eluent additives on analyte ionisatio