Sulfonamide Antibiotics Research Articles

Sulfonamides as tyrosine kinase modulators – A promising class of anticancer agents

Tyrosine kinases are significant mediators of the signaling cascade that play vital role in various biological processes. The involvement of tyrosine kinases in regulating and functioning various metabolic pathways in the body has encouraged scientists to study their role in cancer onset and progression extensively. The human genome consists of over 90 tyrosine kinases, making it a wider research domain. To date, drugs incorporating a wide variety of heterocyclic scaffolds have been developed against many tyrosine kinases. However, factors such as drug resistance, undesirable side effects, and toxicity shown by current anticancer agents are significant challenges. These shortcomings compelled medicinal chemists to ponder the development of variable scaffolds with proficient anticancer activity and minimum toxicity. After the discovery of prontosil (the first sulfonamide antibiotic), molecules with sulfonamide moiety were synthesized and tested for bacterial infections, diabetes, inflammation, glaucoma, etc. and soon sulfonamides with oncotherapeutic effects surfaced. ACK1/TNK, BTK, LMTK3, and EGFR, etc., are some of the enzymes belonging to receptor tyrosine kinase family which are customarily mutated or overexpressed in different types of cancer. These enzymes are now widely explored and modulators of these enzymes having the sulfonamide moiety are steadily being launched. In this review we sight to summarize the chemical and biological aspects of these sulfonamide containing compounds as tyrosine kinase modulators and their role in preventing and terminating the progression of cancer.

Development of a synthesis strategy for sulfamethoxazole derivatives and their coupling with hydrogel microparticles.

Sulfonamides were the first synthetic antibiotics broadly applied in veterinary and human medicine. Their increased use over the last few decades and limited technology to degrade them after entering the sewage system have led to their accumulation in the environment. A new hydrogel microparticle based biosensing application for sulfonamides is developed to overcome existing labour-intensive, and expensive detection methods to analyse and quantify their environmental distribution. This biosensing assay is based on the soft colloidal probe principle and requires microparticle functionalization strategies with target molecules. In this study, we developed a step-wise synthesis approach for sulfamethoxazole (SMX) derivatives in high yield, with SMX being one of the most ubiquitous sulfonamide antibiotics. After de novo synthesis of the SMX derivative, two coupling schemes to poly(ethylene glycol) (PEG) hydrogel microparticles bearing maleimide and thiol groups were investigated. In one approach, we coupled a cysteamine linker to a carboxyl group at the SMX derivative allowing for subsequent binding via the thiol-functionality to the maleimide groups of the microparticles in a mild, high-yielding thiol-ene "click" reaction. In a second approach, an additional 1,11-bis(maleimido)-3,6,9-trioxaundecane linker was coupled to the cysteamine to target the hydrolytically more stable thiol-groups of the microparticles. Successful PEG microparticle functionalization with the SMX derivatives was proven by IR spectroscopy and fluorescence microscopy. SMX-functionalized microparticles will be used in future applications for sulfonamide detection as well as for pull-down assays and screenings for new sulfomethoxazole binding targets.

Direct Z-scheme P-TiO2/g-C3N4 heterojunction for the photocatalytic degradation of sulfa antibiotics.

The construction of direct Z-scheme heterojunctions with high photocatalytic degradation ability is important for wastewater treatment, but there are still many unsolved challenges. In this article, we report the fabrication of a Z-scheme P-TiO2/g-C3N4 (CNPT-X) heterostructure by the calcination method. Under simulated sunlight, CNPT-X composites are found to show excellent degradation performance against sulfonamide antibiotics sulfadiazine (SD), sulfamethazine (SM2), sulfamonomethoxine (SMM), and sulfamethoxazole (SMZ). CNPT-3 (400 mg L-1) can be used to degrade four sulfa antibiotics within 90 min, with a degradation rate as high as 99%, which is higher than that for P-TiO2 and g-C3N4 alone. The internal electron transfer paths and mechanisms for the composites are revealed by ESR radical detection experiments, XPS energy spectrum shifts, valence band positions and active material quenching experiments. Furthermore, the degradation products are analyzed by GC-MS, and four possible degradation pathways for sulfonamide pollutants are proposed. This photocatalyst provides new insights into the fundamental aspects of the photocatalytic degradation mechanism for composite pollutants, as well as new ideas for practical environmental applications.

Improving the sensitivity and selectivity of sulfonamides electrochemical detection with double-system imprinted polymers

The extensive use of antibiotics leading to the rapid spread of antibiotic resistance poses high health risks to humans, but to date there is still lack of an on-site detection method of SA residues. In this study, we integrated radical polymerization using sodium p-styrenesulfonate as a functional monomer and the self-polymerization of dopamine to prepare double-system imprinted polymers (DIPs) using sulfonamide antibiotics as templates. We found that the DIPs were semi-interpenetrating polymer networks and introduction of poly(dopamine) improved the selectivity of the imprinted cavities as well as the conductivity. The selectivity and sensitivity of the sensor using DIPs were much higher than those using single-system MIPs. This sensor could determine sulfonamides in complex samples in the presence of structural analogues. The linear range was from 0.01 to 10.00 μmol L−1 with a detection limit of 4.00 nmol L−1. Furthermore, based on the highly selective DIPs and statistics analysis, this method could be used for simultaneous analysis of 4 sulfonamide types in real samples with an accuracy of 94.87 %. This work provides a strategy to improve the selectivity and sensitivity of MIPs based-sensor that can serve as tool for the simultaneous analysis of antibiotic residues in environment samples.

Enhanced photocatalytic degradation of sulfamethazine by g-C3N4/Cu, N-TiO2 composites under simulated sunlight irradiation

The g-C3N4/Cu, N-TiO2 heterojunction photocatalysts were prepared employing co-precipitation and calcination methods in this work. The as-prepared photocatalysts were characterized using several analytical testing methods such as XRD, SEM, EDS, XPS, UV–vis DRS, and photoluminescence spectra. SEM and EDS analysis confirmed the formation of heterojunction between Cu, N-TiO2 and g-C3N4 and uniform distribution of C, N, Ti, and O elements in the CN/Cu, N-TiO2-1 composite photocatalyst. UV–vis DRS analysis displayed that N and Cu co-doping can reduce the band gap of the involved catalysts, leading to improvement of light absorption. Photoluminescence spectra analysis showed that combining Cu, N-TiO2 and g-C3N4 can improve photogenerated charges separation effectively, demonstrating the formation of g-C3N4/Cu, N-TiO2 heterojunction in CN/Cu, N-TiO2-1 composite photocatalyst. The photocatalytic performance of the synthesized catalysts was evaluated under simulated sunlight irradiation via sulfamethazine (SMZ) degradation experiments. The results displayed that g-C3N4/Cu, N-TiO2-1 heterojunction photocatalyst (with a mass ratio of 1:1 of Cu, N-TiO2 to dicyandiamide) showed the optimum performance with a transformation rate of SMZ of 95.80 % under 240 min irradiation. The plausible photocatalytic mechanism involving g-C3N4/Cu, N-TiO2-1 was proposed according to the trapping experiments of active species, which confirmed that O2•− radicals were the primary active component in photocatalytic degradation of SMZ and h+ and •OH also exhibited significant roles. Furthermore, the main pathways for SMZ degradation were proposed by identifying the involved degradation intermediates. The present research indicates that g-C3N4/Cu, N-TiO2 heterojunction photocatalyst is encouraging for the elimination of sulfonamide antibiotics from actual wastewater.

Efficient Adsorption of a Sulfonamide Antibiotic in Aqueous Solutions with N-doped Magnetic Biochar: Performance, Mechanism, and Reusability.

Conventional biochar has limited effectiveness in the adsorption of sulfonamide antibiotics, while modified biochar exhibits greater adsorption potential. Residues of sulfamethoxazole (SMX) in the aquatic environment can threaten the safety of microbial populations as well as humans. In this study, iron-nitrogen co-doped modified biochar (Fe-N-BC) was prepared from palm fibers and doped with Fe and urea via synthesis at 500 °C. Fe-N-BC has a richer surface functional group based on elemental content, X-ray photoelectron spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The Brunauer-Emmett-Teller (BET) specific surface area test exhibited Fe-N-BC, which possessed a greater surface area (318.203 m2/g) and a better developed pore structure (0.149 cm3/g). The results of the hysteresis loop and the Raman spectrum show that Fe-N-BC has a higher degree of magnetization and graphitization. Fe-N-BC showed a remarkable adsorption capacity for SMX (42.9 mg/g), which could maintain 93.4% adsorption effect after four cycles, and 82.8% adsorption capacity in simulated piggery wastewater. The adsorption mechanism involves pore filling, surface complexation, electrostatic interactions, hydrogen bonding, and π-π EDA interactions. The results of this study show that Fe-N-BC prepared from palm fibers can be a stable, excellent adsorbent for SMX removal from wastewater and has promise in terms of practical applications.

Sewage from a secondary hospital in Ribeirão Preto, southeastern Brazil: a source of multidrug-resistant Enterobacteriaceae.

Antimicrobial resistance is one of the severe threats to global health. Hospital sewage can serve as a reservoir for multi-resistant bacteria and promote the spread of antimicrobial resistance. This study aimed to investigate the antimicrobial susceptibility and the pathogenic potential of Enterobacteriaceae isolated from the sewage of a secondary hospital in Ribeirão Preto, a city in southeastern Brazil. The strains were isolated by membrane filtration and identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF). The antimicrobial susceptibility profile was performed by disk diffusion. Polymerase chain reaction (PCR) assays were used to detect virulence genes among the strains. Twenty-eight isolates were obtained, with Klebsiella pneumoniae being the predominant species (71.4%, n = 20). All isolates were classified as multidrug-resistant, including four isolates that were non-susceptible to at least 50% of the tested antibiotics. All isolates were also non-susceptible to cefuroxime and sulfonamides antibiotics; however, they were susceptible to norfloxacin, ofloxacin, amikacin, gentamicin, netilmicin, ertapenem, cefazolin, cefaclor, and cefotetan. The virulence genes ycfM, fimH, mrkD, kfu, and entB were detected in several isolates. Our study showed that even in a secondary hospital, without the routine of major surgeries and intensive care admissions, the hospital sewage can harbor a high percentage of multidrug-resistant bacteria with pathogenic potential. This leads to the worrying risk of public health and environmental contamination.

Typical Sulfonamide Antibiotics Removal by Biochar-Amended River Coarse Sand during Groundwater Recharge.

The high porosity of medium-coarse sand (MCS) layers in groundwater recharge areas presents a high environmental risk. Sulfamethoxazole (SMX) and trimethoprim (TMP) are two common sulfonamide antibiotics in surface water that have a high propensity to migrate into groundwater. In this study, four biochars were prepared and biochar-amended soil aquifer treatment (SAT) columns were constructed to remove SMX and TMP. Batch experiments demonstrated that the sorption isotherms conformed to the Freundlich model. The maximum adsorptions of biochars prepared at 700 °C were 54.73 and 67.62 mg/g for SMX and 59.3 and 73.38 mg/g for TMP. Electrostatic interaction may be one of the primary mechanisms of adsorption. The column experiments showed that the SMX and TMP removal rate of the biochar-amended SAT was as high as 96%, while that of the MCS SAT was less than 5%. The addition of biochar greatly improved the retention capacity of the pollutants in the MCS layer in the groundwater recharge area and effectively reduced environmental risk.

Analysis of the Comparative Growth Kinetics of Paenarthrobacter ureafaciens YL1 in the Biodegradation of Sulfonamide Antibiotics Based on Substituent Structures and Substrate Toxicity

The high consumption and emission of sulfonamide antibiotics (SAs) have a considerable threat to humans and ecosystems, so there is a need to develop safer and more effective methods than conventional strategies for the optimal removal of these compounds. In this study, four SAs with different substituents, sulfadiazine (SDZ), sulfamerazine (SMR), sulfamethoxazole (SMX), and sulfamethazine (SMZ) were removed by a pure culture of Paenarthrobacter ureafaciens YL1. The effect of the initial SAs concentration on the growth rate of strain YL1 was investigated. The results showed that the strain YL1 effectively removed various SAs in the concentration range of 0.05–2.4 mmol·L−1. The Haldane model was used to perform simulations of the experimental data, and the regression coefficient of the model indicated that the model had a good predictive ability. During SAs degradation, the maximum specific growth rate of strain YL1 was ranked as SMX > SDZ > SMR > SMZ with constants of 0.311, 0.304, 0.302, and 0.285 h−1, respectively. In addition, the biodegradation of sulfamethoxazole (SMX) with a five-membered substituent was the fastest, while the six-membered substituent of SMZ was the slowest based on the parameters of the kinetic equation. Also, density functional theory (DFT) calculations such as frontier molecular orbitals (FMOs), and molecular electrostatic potential map analysis were performed. It was evidenced that different substituents in SAs can affect the molecular orbital distribution and their stability, which led to the differences in the growth rate of strain YL1 and the degradation rate of SAs. Furthermore, the toxicity of P. ureafaciens is one of the crucial factors affecting the biodegradation rate: the more toxic the substrate and the degradation product are, the slower the microorganism grows. This study provides a theoretical basis for effective bioremediation using microorganisms in SAs-contaminated environments.

Hierarchically porous zirconium-based metal–organic frameworks for rapid adsorption and enrichment of sulfonamide antibiotics

Due to serious risk to human health and eco-environmental security, antibiotics in water and foods received considerable concern. Herein, a series of stable hierarchically porous zirconium-based metal–organic frameworks (MOFs) namely HP-NU-902-X were prepared via modulator-induced defect-guided formation strategy for the first time and functioned as sorbents to removal and preconcentration of sulfonamide antibiotics (SAs). The pore size and specific surface area of HP-NU-902-X were systematically adjusted by changing concentration of monocarboxylic acid modulator. The adsorption performance of HP-NU-902-X were greatly improved by forming defects. Experiments demonstrated that HP-NU-902-80 possessed the highest adsorption efficiency to SAs. The limits of detection (S/N = 3) were achieved ranging 0.08 to 0.25 ng/mL. The spiked recoveries of water and milk samples were obtained in the range of 70.34–103.4 % and 73.83–100.5 %. Enrichment factors were calculated between 203 and 358. The SAs can be completely removed within 10 min, and adsorption kinetic data was best consistent with pseudo-second-order model. Using Langmuir isotherm model, maximum adsorption capacities for sulfadiazine, sulfapyridine, sulfametoxydiazine, sulfachloropyridazine, sulfabenzamide and sulfamethazine were calculated as 279.9, 467.7, 414.4, 433.1, 415.5 and 336.6 mg/g, respectively. The improved adsorption capacity was mainly owing to high surface area and extra defect sites. This synthetic strategy provides a way to prepare stable defective MOFs and enhance their potential applications in removal and extraction of environmental pollutants.

New Models for Estimating the Sorption of Sulfonamide and Tetracycline Antibiotics in Soils.

Sulfonamides (SAs) and tetracyclines (TCs) are two classes of widely used antibiotics. There is a lack of easy models for estimating the parameters of antibiotic sorption in soils. In this work, a dataset of affinity coefficients (Kf and Kd) of seven SA/TC antibiotics (i.e., sulfachlorpyridazine, sulfamethazine, sulfadiazine, sulfamethoxazole, oxytetracycline, tetracycline, and chlortetracycline) and associated soil properties was generated. Correlation analysis of these data showed that the affinity coefficients of the SAs were predominantly affected by soil organic matter and cation exchange capacity, while those of the TCs were largely affected by soil organic matter and pH. Pedotransfer functions for estimating Kf and Kd were built by multiple linear regression analysis and were satisfactorily validated. Their performances would be better for soils having higher organic matter content and lower pH. These pedotransfer functions can be used to aid environmental risk assessment, prioritization of antibiotics and identification of vulnerable soils.

Spherical Ni/Ni3Se2 Heterostructure for Efficient Electrochemical Oxidation Reactions

AbstractA Ni/Ni3Se2 metal‐semiconductor heterojunction catalyst with a sphere structure was prepared by a hydrothermal and hydrogen reduction method. The results showed that the heterostructure Ni/Ni3Se2 exhibits better performance than Ni3Se2 and Ni counterparts for electrochemical oxidation reactions. During electrocatalytic water oxidation, the overpotential is 340 mV to reach a catalytic current density of 10 mA cm−2 in 1.0 M KOH solution. The heterogeneous interface formed between the metal Ni and Ni3Se2 in the Ni/Ni3Se2 catalyst can accelerate the electron transfer in the electrochemical oxidation process. Moreover, the as‐prepared material is also applied for sulfonamide degradation, with the aid from hydroxyl radicals generated during water oxidation. This application is meaningful since the product from water oxidation is not desired in hydrogen production from water electrolysis. The material with heterojunctions delivered degradation efficiency up to 80% of sulfonamide antibiotics within 2 h. Therefore, the Ni/Ni3Se2 material might have application prospects in electrochemical sustainability research.

Integrated phycoremediation and ultrasonic-irradiation treatment (iPUT) for the enhanced removal of pharmaceutical contaminants in wastewater

Ultrasonication using low frequencies of sound can increase cell organogenesis, which is beneficial for various industrial applications. This study demonstrates a novel approach of integrated phycoremediation and ultrasonication-irradiation treatment (iPUT) used for improving the degradation of sulfonamide antibiotics via a cumulative effect of combined treatments. Variable ultrasonication treatment (UT) (20 %-2 min to 40 %-10 min) was given to a model microalga, Chlamydomonas mexicana in two ways, 1) single ultrasonic treatment (SUT) and 2) multiple-intermittent ultrasonic treatments (IUT). The microalgal growth was slightly affected by SUT, while it significantly inhibited by IUT. The removal of sulfacetamide and sulfapyridine was significantly improved by >1.7-fold and >1.95-fold at 20 % of SUT and IUT treatment, respectively, compared to control. In the case of sulfamethazine, the SUT showed maximum removal (33.5 %) at 20 %, whereas IUT could achieve 27.5 % removal at the same ultrasonication conditions compared to 9.5 % removal in control. The IUT accelerated the degradation of sulfamethoxazole and sulfadimethoxine more than SUT showing a 9- fold and 12- fold increase in the removal of sulfamethoxazole and sulfadimethoxine with 20 % and 40 % treatments, respectively. The changes in microalgal cell morphology due to ultrasonication treatment were the main cause of enforced uptake and subsequent degradation of these ECs.

Selective photocatalytic removal of sulfonamide antibiotics: The performance differences in molecularly imprinted TiO2 synthesized using four template molecules

Four types of molecularly imprinted TiO2 photocatalysts named MIP-TiO2/sulfadiazine (SD), MIP-TiO2/sulfamethoxazole (SMX), MIP-TiO2/sulfonamide (SN) and MIP-TiO2/aniline (AN), were synthesized. The five catalysts exhibited different degrees of selectivity for two types of sulfonamide antibiotics (SAs), SD and SMX. In the systems of NIP–TiO2, MIP-TiO2/SD, MIP-TiO2/SMX, MIP-TiO2/SN and MIP-TiO2/AN, the degradation rate constants of SD were 0.0789, 0.1031, 0.0859, 0.1034 and 0.1051 min−1, respectively. Moreover, the removal rate constants of SMX on the mentioned catalysts were 0.1076, 0.3250, 0.4260, 0.3885 and 0.5848 min−1, correspondingly. The single bond cleavage (C–S, C–N, and S–N bonds), hydroxylation, ring-opening, oxidation, and deamination were the major transformation pathways of SAs. With the presence of MIP-TiO2/SN and MIP-TiO2/AN, more low molecular weight products were generated, and the intermediates preferred to go through further hydroxylation and oxidation reactions. Therefore, besides MIP-TiO2/SD and MIP-TiO2/SMX, the novel MIP-TiO2/SN and MIP-TiO2/AN, which were prepared by using substances with the similar main functional groups as SAs as template molecules, had excellent catalytic abilities and less byproducts formed in the situation. The results may provide an effective idea to level up the SAs degradation rates, control the generation of intermediates, and reduce environmental risks.

Co–Mn spinel oxides trigger peracetic acid activation for ultrafast degradation of sulfonamide antibiotics: Unveiling critical role of Mn species in boosting Co activity

Activation of peracetic acid (PAA) to generate powerful oxidizing species has become a promising advanced oxidation processes (AOPs) in wastewater treatment, yet the development of low-cost and high-performance activators is still a primary challenge. Herein, a range of Co–Mn spinel oxides (Co3-xMnxO4) with varying levels of Co and Mn were successfully elaborated, in which Co1.1Mn1.9O4 exhibited remarkable performance in PAA activation, outperforming most reported heterogeneous catalysts. Extensive quenching experiments and electron spin resonance (ESR) analysis indicated that acetylperoxyl radical (CH3C(O)OO●) was the predominated oxidizing species responsible for sulfamethoxazole (SMX) degradation. Density functional theory (DFT) calculations revealed that doping with Mn not only promoted the electron transfer and accelerated reduction of Co(III) to Co(II), but also lowered the energy barrier for PAA activation. Moreover, the prominent chemisorption and activation of PAA with Co1.1Mn1.9O4 was also benefitted from the significant role of Mn in optimizing the distribution of bonding and antibonding states on Co 3d orbitals. Unexpectedly, high levels of Cl−greatly facilitated SMX degradation due to the mass production of HOCl from the chain reactions of various radicals with Cl−. This work provides new insights into bimetallic activation of PAA, and the knowledge obtained will further advance the application of PAA-based AOPs.

New insights into the binding mechanism of lysozyme by 2-sulfanilamido-4-methylpyrimidine and 3-sulfanilamido-5-methylisoxazole: Density function theory, multispectral techniques and molecular docking

Over-accumulation of 3-Sulfanilamido-5-methylisoxazole (SMZ) and 2-sulfanilamido-4-methylpyrimidine (SMD) by organisms could lead to irreversible potential toxicity. Herein, the interaction mechanism of SMZ/SMD was demonstrated in combination with multispectral techniques, density functional theory (DFT) and molecular docking with the use of lysozyme (Lys) as a model protein. The quenching of Lys intrinsic fluorescence by SMD is greater than that by SMZ because the affinity of SMD for Lys is stronger than that of SMZ. The binding of SMD/SMZ to Lys is an exothermal process that is carried out automatically (ΔG<0), which is proved by thermodynamic parameters. The concept that the interaction between SMD/SMZ and Lys was mainly achieved through hydrogen bonding and hydrophobic interactions was also validated for molecular docking. These results reveal potential toxicological mechanisms about the interaction of SMD/SMZ with Lys and provide theoretical support for reducing the harm of sulfonamide antibiotics.

TikTok: An Opportunity for Antibiotic Education?

Health information and misinformation on social media have become a growing concern for the medical community. Antimicrobial resistance continues to advance, threatening public health and safety. TikTok, a popular social media platform, provides an avenue for providers to educate patients on clinical topics and medication use. As leaders in patient education and counseling, pharmacists are equipped to provide trustworthy information on TikTok and other platforms. Pharmacists can thus advance the practice of pharmacy and build rapport with patients through a new medium. Current health-related videos on TikTok have not been robustly evaluated for quality and reliability. This study evaluates antibiotic-related content from healthcare providers and non-healthcare providers on TikTok for balance, reliability, and quality using the DISCERN score. Introduction: Antimicrobial resistance is increasing at an alarming rate. Patient education is a critical component of both stewardship and combating health misinformation. TikTok is a video-sharing social media platform with 1 billion monthly users and contains videos that discuss health information. The objective of this study was to evaluate antibiotic-themed TikTok videos for their validity and reliability. Methods: In March 2021, a search on TikTok using the term "antibiotics" was performed and the top 300 consecutive videos were identified. The following data was collected for each video: number of likes, associated disease state, medications, educational aim, mention of COVID-19, and if performed by a healthcare professional (HCP). Non-English language videos were excluded. The DISCERN score was used to evaluate all videos for reliability. Chi-square and Mann-Whitney U were used for statistical analysis. A p-value less than .05 was considered statistically significant. Results: The first 300 consecutive videos were assessed using the DISCERN score for validity. Of the 300 videos, the majority (n=224) were created by non-health care professionals (non-HCPs). The number of "likes" per video ranged from 1 like to 2 million likes with a mean of 34,949 ± 143,482. Videos produced by HCPs were significantly more valid and reliable (mean DISCERN score of 1.65 vs 1.17, p <0.00001) than non-HCPs. They were found to be more relevant (p<0.00001), have clearer aims (p<0.00001), and were more balanced/unbiased (p=0.00188). Videos created by HCPs were more likely to have an educational focus (p<0.0001). There was no difference between groups in clarity of sources utilized or risk/benefits discussed of each treatment. Across all videos, the most common disease states mentioned were urinary tract infection, skin and soft tissue infection, upper respiratory tract infection, and dental infection. Herbal or supplement products, penicillins, and sulfa antibiotics were the most commonly discussed medications. Conclusions: Videos created by HCPs were significantly more valid and reliable than those created by non-HCPs. The videos created by HCPs were also more likely to have clear aims and be more relevant. However, the majority of the videos evaluated were created by non-HCPs. It may be beneficial for HCPs to provide informative TikTok videos that are valid and reliable for patient education.

Oxidation of sulfonamide micropollutants by versatile peroxidase from Bjerkandera adusta

The oxidation of five sulfonamide antibiotics by the versatile peroxidase (VP, EC. 1.11.1.16) from Bjerkandera adusta was quantitatively assessed. The biocatalytic activity of the enzyme was studied by assaying different reaction conditions. Conversion levels were higher than 90 % for all five sulfonamide antibiotics in the model reaction system. In addition, the enzyme performance was also studied in treated wastewater effluents, where three sulfonamide antibiotics were oxidized at a higher level (greater than 85 % oxidation) and two were oxidized at a lower level (up to 50 %). The identified reaction products for two antibiotics, sulfasalazine, and sulfamethoxazole, showed higher antimicrobial activity than the parental compounds. Docking analyses exhibited that the reaction products interacted with the catalytic pocket of the dihydropteroate synthase from Escherichia coli, similar to the parental antibiotics. Though the oxidation is carried out at high velocity and conversion rates, the application of VP in the enzymatic oxidation technology of sulfonamide antibiotics must overcome the production of more toxic products.

Rapid adsorption of sulfamethazine on mesoporous graphene produced from plastic waste: optimization, mechanism, isotherms, kinetics, and thermodynamics

Sulfonamide antibiotics like sulfamethazine (SMZ) can threaten aquatic and terrestrial life even in small concentrations (≤ 1 mg/L); hence, their removal from wastewater is indispensable. However, the need to explore new promising adsorbents that are cheap, effective, and reusable also remains crucial to developing adsorption technology. This work presents a one-pot solvent-free conversion of the current most ubiquitous anthropogenic bio-resistant solid waste (plastics) into valuable carbon materials to remove SMZ from aqueous solution. High-density polyethylene waste was pyrolyzed at 500–1000 °C in an enclosed stainless-steel reactor to produce mesoporous graphene. The graphene products were characterized via microscopic and spectroscopic analyses. The effect of temperature on the graphene yield and properties was investigated. The optimum sulfamethazine (SMZ) adsorption was achieved with 600 °C carbon product (CP-600) due to its high porosity and aromatic structure. The adsorption parameters (pH, catalyst dose, and SMZ concentration) were optimized by response surface methodology (RSM) with a central composite design. 99.99% SMZ removal was achieved at 0.9 g/L adsorbent dose, 12.4 mg/L SMZ concentration, and pH 3 at 25 °C. FTIR analysis revealed that the SMZ adsorption occurred mainly via π–π/π+–π electron interactions between the aromatic and pyrimidine rings of SMZ and the benzene ring of graphitic CP-600. The SMZ adsorption followed the pseudo-second-order kinetics, Langmuir, and Freundlich isotherm models. The adsorption was controlled by film and intraparticle diffusion and was spontaneous and endothermic. The carbon synthesized in this work is reusable and can rapidly remove more SMZ than other SMZ adsorbents.

Utility of a non-target screening method to explore the chlorination of similar sulfonamide antibiotics: Pathways and N[sbnd]Cl intermediates

Sulfonamides (SAs) are ubiquitous antibiotics that are increasingly detected in aquatic environments and can react with free available chlorine to produce transformation products (TPs) during disinfection. However, the TPs generated during chlorination remains poorly understood. Here, a non-target screening method based on the PyHRMS program was used to assess the transformation pathways of five SAs, particularly the transient NCl intermediates, during a simulated chlorination process. We observed 210 TPs during SA chlorination using a non-target screening method based on high-resolution mass spectrometry, and the reaction mechanisms mainly included chlorine substitution, desulfonation, and hydroxylation. Among the TPs, 87 were tentatively proposed to be NCl intermediates as they instantly disappeared after quenching with Na2S2O3. The MS2 spectra of 13 of these potential NCl intermediates were obtained, and all displayed an [M-Cl]+ fragment. A diagnostic fragment ion (DFI) strategy was applied to explore the structural relationship between parent compounds and TPs. Based on the result, five SAs and 101 TPs (if their MS2 spectra were available) could be connected through the same fragments, and this method was also proved effective in a real wastewater treatment plant effluent sample. We believe this novel method can help explore the TPs of organic compounds during chlorination in drinking water plants.