Kovács Kinga Dóra, Novák Martin, Hajnal Zoltán, Hős Csaba, Szabó Bálint, Székács Inna, Fang Ye, Bonyár Attila, Horvath Robert
Nanobiosensorics Laboratory, ELKH EK MFA, Budapest, Hungary; Department of Biological Physics, Eötvös University, Budapest, Hungary.
Nanobiosensorics Laboratory, ELKH EK MFA, Budapest, Hungary.
J Colloid Interface Sci. 2021 Oct;599:620-630. doi: 10.1016/j.jcis.2021.04.091. Epub 2021 Apr 20.
Fluidic flow plays important roles in colloid and interface sciences. Measuring adsorption, aggregation processes and living cell behavior under a fluidic environment with varied flow velocities in a parallel and high-throughput manner remains to be a challenging task. Here a method is introduced to monitor cell response to well-defined flow with varied velocities over an array of label-free resonant waveguide grating (RWG) based optical biosensors. The arrangement consists of a circular well with an array of biosensors at the bottom surface. By rotating the liquid over the biosensor array using a magnetic stirrer bar, flow velocities from zero to a predefined maximum can be easily established over different locations within the biosensor array as characterized in detail by numerical simulations. Cell adhesion and detachment measurements on an Arg-Gly-Asp (RGD) peptide functionalized surface were performed to demonstrate i) measurements at a wide range of simultaneous flow velocities over the same interface; ii) the possibility of parallel measurements at the same flow conditions in one run; and iii) the simple tuning of the employed range of flow velocities. Our setup made it possible to analyze the magnitude and rate of cell detachment at various flow velocities in parallel and determine the critical velocity and force where cells start to detach from the RGD motif displaying biomimetic surface. Furthermore, cellular response to simultaneous mechanical (flow) and chemical stimulation was also investigated using trypsin as a model. This study opens a new possibility to investigate interface phenomena under predefined and conveniently varied flow conditions.
流体流动在胶体与界面科学中发挥着重要作用。以并行且高通量的方式在具有不同流速的流体环境下测量吸附、聚集过程以及活细胞行为仍然是一项具有挑战性的任务。本文介绍了一种方法，用于监测细胞对基于无标记共振波导光栅（RWG）的一系列光学生物传感器上不同流速的明确定义流动的响应。该装置由一个圆形孔组成，在其底面有一排生物传感器。通过使用磁力搅拌棒在生物传感器阵列上方旋转液体，可以在生物传感器阵列内的不同位置轻松建立从零到预定义最大值的流速，数值模拟对此进行了详细表征。在精氨酸 - 甘氨酸 - 天冬氨酸（RGD）肽功能化表面上进行细胞粘附和脱离测量，以证明：i）在同一界面上同时测量广泛范围的流速；ii）在相同流动条件下进行并行测量的可能性；iii）所采用流速范围的简单调节。我们的装置使得能够并行分析不同流速下细胞脱离的幅度和速率，并确定细胞开始从展示仿生表面的RGD基序脱离时的临界速度和力。此外，还使用胰蛋白酶作为模型研究了细胞对同时存在的机械（流动）和化学刺激的反应。这项研究为在预定义且方便变化的流动条件下研究界面现象开辟了新的可能性。
