In this study, we report on new developments, improved results and a new fabrication approach to a micro-electromagnet-based microfluidic device capable of capturing and releasing superparamagnetic beads and bead-bound MCF-7 cancer cells on a sensor site with high efficiency based on the challenges identified and reported in our preliminary studies (Gajasinghe et al. 2016). The device is biocompatible and fabricated by utilizing only traditional microfabrication methods. The microfluidic channel is coated with SU-8 to provide uniform and smooth channel surface for easy release of the captured viable cells without any chemical usage. We labelled MCF-7 cells with superparamagnetic beads via Ep-CAM antibody and observed capture rates of the superparamagnetic beads and MCF-7 cells are 99.9 ± 0.2%, and 94.4 ± 7%, and release efficiencies are 97.4 ± 2%, and 95.2 ± 3%, respectively. Furthermore, there was no significant degrade on viability was observed. Reusability of the device was also presented. Overall, our device is highly efficient, fast, low cost, and has potential be used for cell analysis, drug screening, and disease diagnostics.

在这项研究中，我们报告了基于微电磁的微流控装置的最新进展，改进的结果和新的制造方法，该装置能够高效地捕获和释放超顺磁珠和结合有磁珠的MCF-7癌细胞在传感器位点上在我们的初步研究中发现并报告的挑战（Gajasinghe et al。2016）。该装置是生物相容的，并且仅通过利用传统的微制造方法来制造。微流体通道涂有SU-8，可提供均匀而光滑的通道表面，从而易于释放捕获的活细胞，而无需任何化学使用。我们通过Ep-CAM抗体用超顺磁珠标记MCF-7细胞，观察到超顺磁珠和MCF-7细胞的捕获率为99.9±0.2％和94.4±7％，释放效率为97.4±2％，和95.2±3％。此外，没有观察到生存力的显着降低。还介绍了设备的可重用性。总体而言，我们的设备高效，快速，低成本，并且有潜力用于细胞分析，药物筛选和疾病诊断。