A team of scientists has developed an efficient photocatalyst capable of breaking down sulfamethoxazole (SMX), a broad-spectrum antibiotic, into less harmful chemicals, helping mitigate the health and environmental risks posed by antibiotic contamination. Sulfamethoxazole, commonly used to treat respiratory and urinary tract infections, often finds its way into the environment through human waste, with more than 54% of the consumed antibiotic released via urine and feces.
The study was conducted by researchers from the Institute of Advanced Study in Science and Technology (IASST), Guwahati—an autonomous institute under the Department of Science and Technology. Led by Professor Devasish Chowdhury, the team synthesized copper zinc tin sulfide (CZTS) nanoparticles and a CZTS-tungsten disulfide (CZTS-WS2) composite. These materials were found to exhibit strong photocatalytic properties, making them effective in degrading sulfamethoxazole into less toxic compounds.
The CZTS and its composite are quaternary semiconductors composed of earth-abundant, cost-effective, and non-toxic materials. “These materials exhibit exceptional photostability, making them highly suitable for light-harvesting and photocatalytic applications,” explained Prof. Chowdhury. The CZTS-WS2 composite was synthesized using a hydrothermal reaction involving zinc chloride, copper chloride, tin chloride, and tungsten disulfide.
The catalyst was found to not only efficiently degrade sulfamethoxazole but also maintain its effectiveness across multiple uses, ensuring economic viability. According to the research team, the composite could be recovered and reused without a significant reduction in performance, making it a sustainable solution to antibiotic contamination.
Liquid chromatography–mass spectrometry (LC-MS) was used to analyze the products formed during the degradation process. This technique allowed the researchers to identify the intermediates and breakdown products generated from sulfamethoxazole. The study, published in Journal of Photochemistry & Photobiology A, confirmed that most of the intermediates were less hazardous than the original antibiotic.
In addition to its photocatalytic efficiency, the CZTS-WS2 composite demonstrated more than 80% radical scavenging activity and antibacterial properties. These capabilities make it particularly promising for use in wastewater treatment systems, where it could help address both antibiotic contamination and bacterial resistance.
Antibiotic pollution poses several challenges, including ecological disruption, the emergence of antibiotic resistance, and risks to human health. With the rise in antibiotic use and environmental contamination, finding sustainable solutions has become imperative. This new development represents a significant step toward minimizing the environmental impact of pharmaceuticals and ensuring safer ecosystems.
The team involved in this study included Nur Jalal Mondal, Rahul Sonkar, Mridusmita Barman, and Dr. Mritunjoy Prasad Ghosh. Their work demonstrates how innovative materials and processes can contribute to solving pressing environmental issues by offering practical, cost-effective solutions.
(Input from various sources)
(Rehash/Ankur Deka/MSM)
