Mobilefuge: A low-cost, portable, open source, 3D-printed centrifuge that can be used for purification of saliva samples to detect SARS-CoV2

One of the best ways to contain the spread of COVID-19 is frequent testing of as many people as possible and timely isolation of uninfected personnel from infected personnel. However, the cost of massive testing is not affordable in many countries. The existing technologies might not be scalable to offer affordable and timely testing for millions of people. To address this issue, novel testing methods based on Loop-Mediated Isothermal Amplification (LAMP) were proposed that are more sensitive, require less reagents and can work with saliva samples instead of more tedious nasal swabs. As a result, LAMP based protocols can make it possible to drive the cost down to one dollar per test. These LAMP based methods require a centrifuge device, mostly for separation of viral particles from reaction inhibitors in saliva samples. However, centrifuge is neither accessible nor affordable in many resource limited settings, especially during this pandemic situation when normal supply chains are heavily disrupted. To overcome these challenges, we invented a low-cost centrifuge that can be useful for carrying out low-cost LAMP based detection of SARS-Cov2 virus in saliva. The 3D printed centrifuge (Mobilefuge) is portable, robust, stable, safe, easy to build and operate. The Mobilefuge doesn't require soldering or programming skills and can be built without any specialised equipment, yet practical enough for high throughput use. More importantly, Mobilefuge can be powered from widely available USB ports, including mobile phones and associated power supplies. This allows the Mobilefuge to be used even in off-grid and resource limited settings. We believe that our invention will aid the efforts to contain the spread of COVID-19 by lowering the costs of testing equipment. Apart from the COVID-19 testing, the Mobilefuge can have applications in the field of biomedical research and diagnostics.遏制新型冠状病毒肺炎（COVID-19）传播的最优路径之一，便是对尽可能多的人群开展高频次检测，并及时实现未感染者与感染者的隔离。然而，大规模检测的成本在诸多国家难以承担。现有技术难以实现规模化应用，无法为数百万民众提供兼具经济性与时效性的检测服务。为解决这一痛点，研究者提出了基于环介导等温扩增（Loop-Mediated Isothermal Amplification, LAMP）的新型检测方案。该类方法灵敏度更优、所需试剂更少，且可直接采用唾液样本，无需繁琐的鼻咽拭子采样流程。据此，基于LAMP的检测协议可将单份检测成本降至1美元。不过此类方法需借助离心机设备，主要用于从唾液样本中分离病毒颗粒与反应抑制剂。但在许多资源匮乏地区，尤其是在本次疫情期间全球供应链遭受严重冲击的背景下，离心机既难以获取，也难以负担。为攻克这些挑战，我们研发了一款低成本离心机，可用于开展基于LAMP的唾液样本严重急性呼吸综合征冠状病毒2型（SARS-CoV-2）病毒检测。这款3D打印离心机（Mobilefuge）便携耐用、运行稳定安全，且易于搭建与操作。Mobilefuge无需焊接或编程技能，无需任何专业设备即可完成组装，同时足以满足高通量使用需求。更关键的是，Mobilefuge可通过随处可见的USB端口供电，包括移动电话及其配套电源。这使得该设备甚至可在无电网覆盖及资源匮乏的场景中投入使用。我们认为，本发明可通过降低检测设备的成本，助力遏制新冠病毒的传播。除新冠病毒检测外，Mobilefuge还可应用于生物医学研究与诊断领域。