Point-of-care diagnostic devices for both physicians and patients themselves are now ubiquitous, but often not sensitive enough for highly dilute analytes (e.g., pre-symptomatic viral detection). Two primary methods to address this challenge include (1) increasing the sensitivity of molecular recognition elements with greater binding affinity to the analyte or (2) increasing the concentration of the analyte being detected in the sample itself (preconcentration). The latter approach, preconcentration, is arguably more attractive if it can be made universally applicable to a wide range of analytes. In this study, pressure-driven membrane preconcentration devices were developed, and their performance was analyzed for detecting target analytes in biofluids in the form of point-of-care lateral-flow assays (LFAs). The demonstrated prototypes utilize negative or positive pressure gradients to move both water and small interferents (salt, pH) through a membrane filter, thereby concentrating the analyte of interest in the remaining sample fluid. Preconcentration up to 33× is demonstrated for influenza A nucleoprotein with a 5 kDa pore polyethersulfone membrane filter. LFA results are obtained within as short as several minutes and device operation is simple (very few user steps), suggesting that membrane preconcentration can be preferable to more complex and slow conventional preconcentration techniques used in laboratory practice.

中文翻译：

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压力驱动的膜预浓缩分析，用于即时检测。

医生和患者本身的即时诊断设备现在无处不在，但通常对高度稀释的分析物（例如，症状前病毒检测）不够敏感。解决这一挑战的两种主要方法包括 (1) 提高对分析物具有更大结合亲和力的分子识别元件的灵敏度或 (2) 提高样品本身中被检测分析物的浓度（预浓缩）。后一种方法，即预浓缩，如果可以普遍适用于广泛的分析物，则可以说更有吸引力。在这项研究中，开发了压力驱动的膜预浓缩装置，并分析了它们的性能，以检测床旁侧流分析 (LFA) 形式的生物流体中的目标分析物。演示的原型利用负压或正压梯度使水和小干扰物（盐、pH）通过膜过滤器，从而将感兴趣的分析物浓缩到剩余的样品流体中。使用 5 kDa 孔聚醚砜膜过滤器证明甲型流感核蛋白的预浓缩高达 33 倍。LFA 结果可在短短几分钟内获得，并且设备操作简单（用户步骤很少），这表明膜预浓缩比实验室实践中使用的更复杂和更慢的传统预浓缩技术更可取。使用 5 kDa 孔聚醚砜膜过滤器证明甲型流感核蛋白的预浓缩高达 33 倍。LFA 结果可在短短几分钟内获得，并且设备操作简单（用户步骤很少），这表明膜预浓缩比实验室实践中使用的更复杂和更慢的传统预浓缩技术更可取。使用 5 kDa 孔聚醚砜膜过滤器证明甲型流感核蛋白的预浓缩高达 33 倍。LFA 结果可在短短几分钟内获得，并且设备操作简单（用户步骤很少），这表明膜预浓缩比实验室实践中使用的更复杂和更慢的传统预浓缩技术更可取。