We report on a microsystem that couples high-throughput bacterial immunomagnetic capture to contact-free cell lysis using an alternating current magnetic field (AMF) to enable downstream molecular characterization of bacterial nucleic acids. Traditional methods for cell lysis rely on either dilutive chemical methods, expensive biological reagents, or imprecise physical methods. We present a microchip with a magnetic polymer substrate (Mag-Polymer microchip), which enables highly controlled, on-chip heating of biological targets following exposure to an AMF. First, we present a theoretical framework for the quantitation of power generation for single-domain magnetic nanoparticles embedded in a polymer matrix. Next, we demonstrate successful bacterial DNA recovery by coupling (1) high-throughput, sensitive microfluidic immunomagnetic capture of bacteria to (2) on-chip, contact-free bacterial lysis using an AMF. The bacterial capture efficiency exceeded 76% at 50 ml/h at cell loads as low as ∼10 CFU/ml, and intact DNA was successfully recovered at starting bacterial concentrations as low as ∼1000 CFU/ml. Using the presented methodology, cell lysis becomes non-dilutive, temperature is precisely controlled, and potential contamination risks are eliminated. This workflow and substrate modification could be easily integrated in a range of micro-scale diagnostic systems for infectious disease.

中文翻译：

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细菌的微流体富集与磁性聚合物表面上的无接触裂解相结合，用于下游分子检测。

我们报告了一个微系统，该系统将高通量细菌免疫磁捕获与使用交流磁场（AMF）的无接触细胞裂解相结合，以实现细菌核酸的下游分子表征。传统的细胞裂解方法依赖于稀释化学方法，昂贵的生物试剂或不精确的物理方法。我们提出了一种具有磁性聚合物基板的微芯片（Mag-Polymer微芯片），该芯片可在暴露于AMF之后对生物靶标进行高度可控的芯片上加热。首先，我们为嵌入聚合物基质中的单畴磁性纳米颗粒的发电量定量提供了理论框架。接下来，我们通过偶联（1）高通量证明成功的细菌DNA回收，使用AMF对细菌进行敏感的微流体免疫磁捕获，以（2）在芯片上进行非接触式细菌裂解。在低至约10 CFU / ml的细胞负荷下，在50 ml / h的细菌捕获效率超过76％，并且在低至约1000 CFU / ml的起始细菌浓度下成功回收了完整的DNA。使用提出的方法，细胞裂解变得非稀释性，温度得到精确控制，并且消除了潜在的污染风险。这种工作流程和底物修饰可以轻松地集成到一系列传染病的微型诊断系统中。并以起始细菌浓度低至约1000 CFU / ml成功回收了完整的DNA。使用提出的方法，细胞裂解变得无稀释作用，温度得到精确控制，并且消除了潜在的污染风险。这种工作流程和底物修饰可以轻松地集成到一系列传染病的微型诊断系统中。并以起始细菌浓度低至约1000 CFU / ml成功回收了完整的DNA。使用提出的方法，细胞裂解变得非稀释性，温度得到精确控制，并且消除了潜在的污染风险。这种工作流程和底物修饰可以轻松地集成到各种传染病的微型诊断系统中。