Reagent-free and portable detection of Bacillus anthracis spores using a microfluidic incubator and smartphone microscope
Reagent-free and portable detection of Bacillus anthracis spores using a microfluidic incubator and smartphone microscope
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DOI：
10.1039/c5an01304f
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发表时间：
2015-01-01
期刊：
影响因子：
4.2
通讯作者：
Kelly, Ryan T.
中科院分区：
文献类型：
--
作者：
Hutchison, Janine R.;Erikson, Rebecca L.;Kelly, Ryan T.
炭疽芽孢杆菌是炭疽病的病原体，可由人类和食草性哺乳动物通过吸入、摄入或皮肤接触细菌孢子而感染。由于炭疽杆菌的稳定性和致病潜力，炭疽杆菌是公认的生物制剂，需要强有力的检测和生存方法来鉴定未知样本中的孢子。在这里，我们报告使用基于智能手机的显微镜(SPM)与简单的微流控培养设备(MID)相结合，在3到5小时内检测到50到5000个炭疽芽胞。这项技术依赖于光学监测将类似于1微米的孢子转化为长度从几十微米到数百微米的丝状营养细胞。与蜡状芽孢杆菌的其他成员相比，这种独特的细丝形成是炭疽杆菌所特有的。这种方法的一个独特特点是保持了样品的完整性，并且可以从芯片上去除营养生物量，用于二次分子分析，如聚合酶链式反应。与现有的基于芯片的快速活性聚合酶链式反应方法相比，这种新方法将检测时间减少了近一半，并且具有高度的敏感性、特异性和成本效益。
Bacillus anthracis is the causative agent of anthrax and can be contracted by humans and herbivorous mammals by inhalation, ingestion, or cutaneous exposure to bacterial spores. Due to its stability and disease potential, B. anthracis is a recognized biothreat agent and robust detection and viability methods are needed to identify spores from unknown samples. Here we report the use of smartphone-based microscopy (SPM) in combination with a simple microfluidic incubation device (MID) to detect 50 to 5000 B. anthracis Sterne spores in 3 to 5 hours. This technique relies on optical monitoring of the conversion of the similar to 1 mu m spores to the filamentous vegetative cells that range from tens to hundreds of micrometers in length. This distinguishing filament formation is unique to B. anthracis as compared to other members of the Bacillus cereus group. A unique feature of this approach is that the sample integrity is maintained, and the vegetative biomass can be removed from the chip for secondary molecular analysis such as PCR. Compared with existing chip-based and rapid viability PCR methods, this new approach reduces assay time by almost half, and is highly sensitive, specific, and cost effective.