{"title":"Ultrasensitive electrochemical detection of methotrexate in biological fluids using NiMn2O4/CNT nanocomposite-modified electrode†","authors":"Nasir Abbas and Tae Hyun Kim","doi":"10.1039/D5SD00064E","DOIUrl":null,"url":null,"abstract":"<p >Methotrexate (MTX) is a widely used chemotherapeutic drug with a narrow therapeutic index, making its precise monitoring crucial for effective treatment and minimizing side effects. This study focuses on the development of a clinically applicable NiMn<small><sub>2</sub></small>O<small><sub>4</sub></small>/CNT nanocomposite-modified glassy carbon electrode (NiMn<small><sub>2</sub></small>O<small><sub>4</sub></small>/CNT-GCE) for the sensitive and selective electrochemical detection of MTX. The NiMn<small><sub>2</sub></small>O<small><sub>4</sub></small> nanomaterial was synthesized <em>via</em> a co-precipitation method followed by calcination, and its composite with CNTs was optimized to enhance electrochemical performance. The sensor demonstrated a detection limit as low as 0.627 nM and a broad linear detection range (0.05–3 μM), attributed to the synergistic effects of NiMn<small><sub>2</sub></small>O<small><sub>4</sub></small> and CNTs that enhance electron transfer and active site availability. Moreover, the NiMn<small><sub>2</sub></small>O<small><sub>4</sub></small>/CNT-GCE was successfully applied to detect MTX in spiked serum and urine samples, achieving recovery rates of 96–99% with relative standard deviations below 3.5%. Its minimal interference with common metabolites and excellent stability makes it ideal for therapeutic drug monitoring. This work underscores the potential of NiMn<small><sub>2</sub></small>O<small><sub>4</sub></small>/CNT as a promising platform for real-time clinical diagnostics and advanced electrochemical sensing applications.</p>","PeriodicalId":74786,"journal":{"name":"Sensors & diagnostics","volume":" 9","pages":" 803-814"},"PeriodicalIF":4.1000,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sd/d5sd00064e?page=search","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Sensors & diagnostics","FirstCategoryId":"1085","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2025/sd/d5sd00064e","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, ANALYTICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Methotrexate (MTX) is a widely used chemotherapeutic drug with a narrow therapeutic index, making its precise monitoring crucial for effective treatment and minimizing side effects. This study focuses on the development of a clinically applicable NiMn2O4/CNT nanocomposite-modified glassy carbon electrode (NiMn2O4/CNT-GCE) for the sensitive and selective electrochemical detection of MTX. The NiMn2O4 nanomaterial was synthesized via a co-precipitation method followed by calcination, and its composite with CNTs was optimized to enhance electrochemical performance. The sensor demonstrated a detection limit as low as 0.627 nM and a broad linear detection range (0.05–3 μM), attributed to the synergistic effects of NiMn2O4 and CNTs that enhance electron transfer and active site availability. Moreover, the NiMn2O4/CNT-GCE was successfully applied to detect MTX in spiked serum and urine samples, achieving recovery rates of 96–99% with relative standard deviations below 3.5%. Its minimal interference with common metabolites and excellent stability makes it ideal for therapeutic drug monitoring. This work underscores the potential of NiMn2O4/CNT as a promising platform for real-time clinical diagnostics and advanced electrochemical sensing applications.