Zhang Yu Shrike, Santiago Grissel Trujillo-de, Alvarez Mario Moisés, Schiff Steven J, Boyden Edward S, Khademhosseini Ali
Biomaterials Innovation Research Center, Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston 02139, MA, USA.
Harvard-MIT Division of Health Sciences and Technology, Cambridge 02139, MA, USA.
Curr Opin Biomed Eng. 2017 Mar;1:45-53. doi: 10.1016/j.cobme.2017.03.001. Epub 2017 Mar 22.
Diagnostics play a significant role in health care. In the developing world and low-resource regions the utility for point-of-care (POC) diagnostics becomes even greater. This need has long been recognized, and diagnostic technology has seen tremendous progress with the development of portable instrumentation such as miniature imagers featuring low complexity and cost. However, such inexpensive devices have not been able to achieve a resolution sufficient for POC detection of pathogens at very small scales, such as single-cell parasites, bacteria, fungi, and viruses. To this end, expansion microscopy (ExM) is a recently developed technique that, by physically expanding preserved biological specimens through a chemical process, enables super-resolution imaging on conventional microscopes and improves imaging resolution of a given microscope without the need to modify the existing microscope hardware. Here we review recent advances in ExM and portable imagers, respectively, and discuss the rational combination of the two technologies, that we term expansion mini-microscopy (ExMM). In ExMM, the physical expansion of a biological sample followed by imaging on a mini-microscope achieves a resolution as high as that attainable by conventional high-end microscopes imaging non-expanded samples, at significant reduction in cost. We believe that this newly developed ExMM technique is likely to find widespread applications in POC diagnostics in resource-limited and remote regions by expanded-scale imaging of biological specimens that are otherwise not resolvable using low-cost imagers.
诊断在医疗保健中发挥着重要作用。在发展中世界和资源匮乏地区，即时检验（POC）诊断的实用性变得更加突出。这种需求早已得到认可，随着便携式仪器的发展，如具有低复杂性和低成本的微型成像仪，诊断技术取得了巨大进步。然而，这种廉价设备在非常小的尺度上，如单细胞寄生虫、细菌、真菌和病毒，还无法实现足以进行病原体POC检测的分辨率。为此，扩展显微镜技术（ExM）是一种最近开发的技术，通过化学过程对保存的生物标本进行物理扩展，能够在传统显微镜上实现超分辨率成像，并提高给定显微镜的成像分辨率，而无需修改现有的显微镜硬件。在这里，我们分别回顾了ExM和便携式成像仪的最新进展，并讨论了这两种技术的合理结合，我们将其称为扩展微型显微镜技术（ExMM）。在ExMM中，生物样品的物理扩展随后在微型显微镜上成像，可实现与传统高端显微镜对未扩展样品成像时相当的分辨率，同时成本大幅降低。我们相信，这种新开发的ExMM技术可能会通过对使用低成本成像仪无法分辨的生物标本进行扩展规模成像，在资源有限和偏远地区的POC诊断中得到广泛应用。
