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COVID-19（新型冠状病毒肺炎）传播的最优途径之一，是对尽可能多的人群开展高频次检测，并及时将未感染者与感染者进行隔离。但大规模检测的成本在诸多国家难以承担，现有技术也无法实现规模化，为数百万民众提供负担得起且及时的检测服务。为解决这一痛点，研究人员提出了基于环介导等温扩增（Loop-Mediated Isothermal Amplification, LAMP）的新型检测方法，此类方法灵敏度更高、所需试剂更少，且可采用唾液样本替代繁琐的鼻拭子采样。据此，基于LAMP的检测方案可将单次检测成本降至1美元。这类基于LAMP的检测方法需使用离心机设备，主要用于从唾液样本中分离病毒颗粒与反应抑制剂。然而，在许多资源受限地区，尤其是本次疫情大流行期间全球供应链遭遇严重冲击的情况下，离心机既难以获取，也无力负担。为攻克这些难题，我们研发了一款低成本离心机，可用于低成本开展基于LAMP的唾液样本SARS-CoV-2（严重急性呼吸综合征冠状病毒2型）检测。这款3D打印离心机（Mobilefuge）便携、坚固、稳定、安全，且易于搭建与操作，无需焊接或编程技能，也无需任何专用设备即可完成组装，同时足以满足高通量使用需求。更为关键的是，Mobilefuge可通过广泛普及的USB端口供电，包括移动电话及其配套电源，这使其甚至可在无电网覆盖以及资源匮乏的场景中投入使用。我们相信，此项研发成果可通过降低检测设备成本，助力遏制COVID-19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。