Hangzhou Institute of Technology, Xidian University, Hangzhou, 311231, China; Department of Biomedical Engineering, University of Connecticut, Storrs, CT, 06269, USA.
Department of Biomedical Engineering, University of Connecticut, Storrs, CT, 06269, USA.
Biosens Bioelectron. 2023 Mar 15;224:115049. doi: 10.1016/j.bios.2022.115049. Epub 2022 Dec 31.
Imaging a large number of bio-specimens at high speed is essential for many biomedical applications. The common strategy is to place specimens at different lateral positions and image them sequentially. Here we report a new on-chip imaging strategy, termed depth-multiplexed ptychographic microscopy (DPM), for parallel imaging and sensing at high speed. Different from the common strategy, DPM stacks multiple specimens in the axial direction and images the entire z-stack all at once. In our prototype platform, we modify a low-cost car mirror for programmable steering of the incident laser beam. A blood-coated image sensor is then placed underneath the stacked sample for acquiring the resulting diffraction patterns. With the captured images, we perform blind recovery of the incident beam angle and model different layers of the stacked sample as different coded surfaces for object reconstruction. For in vitro experiment, we demonstrate time-lapse cell culture monitoring by imaging 3 stacked microfluidic channels on the coded sensor. For high-throughput cytometric analysis, we image 5 stacked brain sections with a 205-mm field of view in ∼50 s. Cytometric analysis is also performed to quantify the cellular proliferation biomarkers on the slides. The DPM approach adds a new degree of freedom for data multiplexing in microscopy, enabling parallel imaging of multiple specimens using a single detector. The demonstrated 6-mm depth of field is among the longest ones in microscopy imaging. The novel depth-multiplexed configuration also complements the miniaturization provided by microfluidics devices, offering a solution for on-chip sensing and imaging with efficient sample handling.
高速对大量生物样本成像对于许多生物医学应用至关重要。常见的策略是将样本放置在不同的横向位置，并依次对其进行成像。在这里，我们报告了一种新的片上成像策略，称为深度复用相衬显微镜（DPM），用于高速并行成像和传感。与常见策略不同，DPM 在轴向堆叠多个样本，并一次性对整个 z 堆叠进行成像。在我们的原型平台中，我们修改了低成本的汽车后视镜，以实现入射激光束的可编程转向。然后将涂有血液的图像传感器放置在堆叠样本的下方，用于获取产生的衍射图案。使用捕获的图像，我们执行入射光束角度的盲目恢复，并将堆叠样本的不同层建模为不同的编码表面，用于物体重建。在体外实验中，我们通过对编码传感器上的 3 个堆叠微流控通道进行成像，演示了细胞培养的时间 lapse 监测。对于高通量细胞计量分析，我们在约 50 s 内对 5 个堆叠的脑切片进行成像，视野为 205mm。还对幻灯片上的细胞增殖生物标志物进行了细胞计量分析。DPM 方法为显微镜中的数据复用增加了一个新的自由度，允许使用单个探测器对多个样本进行并行成像。所展示的 6mm 景深是显微镜成像中最长的景深之一。新的深度复用配置还补充了微流控器件提供的小型化，为芯片上的传感和成像提供了高效样本处理的解决方案。
