Abstract 4-methylmethcathinone (mephedrone) has emerged in drug seizures as a new psychoactive substance (NPS) causing a public health risk of global concern. Currently, there are no commercial microfluidic devices for the selective detection of mephedrone and so this study presents a simple, low cost and portable paper-based Lab-on-a-Chip (LOC) device with colorimetric detection to fill this gap. Limits of detection for mephedrone in spiked urine and dissolved powder (aqueous) samples are clinically relevant at 4.34 ng mL-1 and 2.51 ng mL-1 respectively. No cross-reactivity for commonly encountered cutting agents, interferents and adulterants were detected. Mephedrone and its main metabolite were detectable in aqueous samples within 3 minutes. Stability and reproducibility measurements showed no significant difference in signal intensity over eight weeks and no significant difference within or between devices. The proposed device has the potential to provide cost-effective, rapid, on-site testing within forensic or clinical settings and therefore has wide global applicability.

中文翻译：

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Origami Chips：开发和验证基于纸的芯片实验室设备，用于快速且经济高效地检测尿液中的 4-甲基甲卡西酮（甲氧麻黄酮）及其代谢物 4-甲基麻黄碱

摘要 4-甲基甲卡西酮（mephedrone）作为一种新的精神活性物质（NPS）出现在缉获的毒品中，引起全球关注的公共卫生风险。目前，没有用于选择性检测甲氧麻黄酮的商用微流体设备，因此本研究提出了一种简单、低成本、便携式的纸质实验室芯片 (LOC) 设备，该设备具有比色检测功能，以填补这一空白。加标尿液和溶解粉末（水溶液）样品中甲氧麻黄酮的检测限分别为 4.34 ng mL-1 和 2.51 ng mL-1，具有临床意义。未检测到与常见切削剂、干扰物和掺杂物的交叉反应。在 3 分钟内即可在水性样品中检测到甲氧麻黄酮及其主要代谢物。稳定性和再现性测量显示八周内信号强度没有显着差异，设备内部或设备之间也没有显着差异。所提议的设备有可能在法医或临床环境中提供具有成本效益的快速现场测试，因此具有广泛的全球适用性。