Shao Jin-Yu
Department of Biomedical Engineering, Washington University, Saint Louis, MO 63130-4899, USA.
Ann Biomed Eng. 2002 Apr;30(4):546-54. doi: 10.1114/1.1476017.
A novel technique of imposing femtonewton forces with micropipette aspiration [i.e., the extended micropipette aspiration technique (EMAT)] is proposed, and an axisymmetric finite element analysis of this technique is provided. The EMAT is experimentally based upon a micropipette manipulation system and is theoretically based upon hydrodynamics. Any spherical object such as a human neutrophil or a latex bead can be employed as the force transducer, so cell-cell interactions can be directly studied. Our computational analysis shows that femtonewton forces can indeed be imposed. The force magnitude is sensitive to the radius of the micropipette and the micropipette-transducer distance, but it is much less sensitive to other parameters including the radius of the transducer, the substrate curvature, and the thickness of the micropipette wall. Combining the EMAT and the previously developed micropipette aspiration technique will allow us to impose an unprecedented range of forces, from a few femtonewtons to a few hundred piconewtons on single molecules or receptor-ligand bonds.
提出了一种利用微量移液器抽吸施加飞牛顿力的新技术[即扩展微量移液器抽吸技术（EMAT）]，并对该技术进行了轴对称有限元分析。EMAT在实验上基于微量移液器操作系统，在理论上基于流体动力学。任何球形物体，如人类中性粒细胞或乳胶珠，都可用作力传感器，因此可以直接研究细胞间相互作用。我们的计算分析表明，确实可以施加飞牛顿力。力的大小对微量移液器的半径和微量移液器与传感器的距离敏感，但对其他参数（包括传感器的半径、基底曲率和微量移液器壁的厚度）的敏感性要低得多。将EMAT与先前开发的微量移液器抽吸技术相结合，将使我们能够在单个分子或受体-配体键上施加前所未有的力范围，从几飞牛顿到几百皮牛顿。
