Methotrexate degradation in artificial wastewater using non-thermal pencil plasma jet

Abstract

The rising global cancer rate is driving up the consumption of anticancer drugs. This causing a noticeable increase in the levels of these drugs in wastewater. The drugs are not metabolized effectively by the human body, leading to their presence in human waste, as well as in the 2 effluent from hospitals and drug manufacturing industries. Methotrexate is a commonly used drug for treating various types of cancer. Its complex organic structure makes it difficult to degrade using conventional methods. The present work proposed a non-thermal pencil plasma jet treatment for methotrexate degradation. The air plasma produced in this jet setup is electrical characterized and plasma species/radicals are identified using emission spectroscopy. The degradation of drug is monitored by studying the change in solution physiochemical properties, HPLC-UV analysis, and removal of total organic carbon, etc.Results show that a 9-minute plasma treatment completely degraded the drug solution that followed first order degradation kinetics with rate constant 0.38 min -1 and 84.54% mineralization was observed. Additionally, an increase in electrical conductivity and dissolved solids compared to virgin water-plasma interaction indicated the formation of new, smaller compounds (2,4-Diaminopteridine-6-carboxylic acid, N-(4-Aminobenzoyl)-L-glutamic acid, etc.) after drug degradation. The plasma-treated methotrexate solution also showed lower toxicity towards freshwater chlorella algae compared to the untreated solution. Finally, it can be said that non-thermal plasma jets are economically and environmentally friendly devices that have the potential to be used for the treatment of complex and resistive anticancer drugpolluted wastewaters.

Production of Alkaline Plasma Activated Tap Water Using Different Plasma Forming Gas at Sub-Atmospheric Pressure

“…These current laments indicate the formation of various reactive species and radicals during air discharge in each rising and falling current half-cycle (46). The resulting radicals and species dissolved in water during the plasma-water interaction, giving rise to plasma-activated water (6, 15,18,19,22,26,[47][48][49].…”

Degradation of dyes using reactive species of atmospheric pressure dielectric barrier discharge formed by a pencil plasma jet

“…These HO• radical oxidized the dissolved organic waste to simpler non-toxic compounds in wastewater. Along with HO• radical other oxidizing species such as ozone (O 3 ), hydrogen peroxide (H 2 O 2 ), etc also play an important role in the AOPs [3][4][5][6][7][8][9][10].…”

Assessing the Preservation Effectiveness: A Comparative Analysis of Plasma Activated Water and Various Preservatives on Capsicum annuum L. (Jalapeño and Pusa Jwala)

“…), etc. (29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43) Previous research has explored the efficacy of PAW in preserving various foods, including grapes, Chinese bayberries, button mushrooms, fresh-cut apples, lemons, Korean rice cake, shrimps, tofu, chicken meat, etc. (12,13,19,23,(26)(27)(28)(44)(45)(46)(47) The preservation ability of PAW is attributed to the presence of radicals/species such as hydroxyl radicals (·OH), dissolved ozone (O 3 ), hydrogen peroxide (H 2 O 2 ), peroxynitrite (ONOOˉ), and reactive nitrogen species like NO 2 ˉ and NO 3 ˉ, providing an acidic environment that limits microbial growth (21,34,37,44,(46)(47)(48)(49).…”