The active flagellum propels a motile sperm cell by traveling bending waves. Here, we demonstrate that non-motile cells have the capacity to be wirelessly actuated by external magnetic fields and reveal insights into their propulsion characteristics. Partial coating of the sperm head with nanoparticle aggregates is achieved by electrostatic-based self-assembly. The coating enables propagation of helical traveling waves along the passive flagellum under the action of a periodic magnetic field. We compare the waveforms of active and passive flagellated motion and show noticeable asymmetry in the case of magnetically actuated cells, leading to lower linearity ( LIN = VSL / VCL) of the taken pathway. The average curvature of the flagellar beat cycle is 10.4 ± 8.1 rad mm−1 ( mean ± s . d .) for an active flagellum, whereas the curvature of a passive flagellum exhibits a linear increase (37.4 ± 18.1 rad mm−1) and decreases toward the distal end. We also show that the maximum amplitude of the bending wave occurs at the distal end of the active flagellum and at the middle of the passive flagellum. Our experiments also show the ability of the actuating field to control the rate of progression of the bending waves along the passive flagellum to match that of motile cells.The active flagellum propels a motile sperm cell by traveling bending waves. Here, we demonstrate that non-motile cells have the capacity to be wirelessly actuated by external magnetic fields and reveal insights into their propulsion characteristics. Partial coating of the sperm head with nanoparticle aggregates is achieved by electrostatic-based self-assembly. The coating enables propagation of helical traveling waves along the passive flagellum under the action of a periodic magnetic field. We compare the waveforms of active and passive flagellated motion and show noticeable asymmetry in the case of magnetically actuated cells, leading to lower linearity ( LIN = VSL / VCL) of the taken pathway. The average curvature of the flagellar beat cycle is 10.4 ± 8.1 rad mm−1 ( mean ± s . d .) for an active flagellum, whereas the curvature of a passive flagellum exhibits a linear increase (37.4 ± 18.1 rad mm−1) and decreases toward the distal end. We also show that the maximum amplitude of the bending wav...

中文翻译：

---

运动和磁驱动精子细胞之间的相似性

活跃的鞭毛通过行进的弯曲波推动活动的精子细胞。在这里，我们证明了非运动细胞具有被外部磁场无线驱动的能力，并揭示了对其推进特性的见解。通过基于静电的自组装实现了用纳米颗粒聚集体部分涂覆精子头部。该涂层能够在周期性磁场的作用下沿着被动鞭毛传播螺旋行波。我们比较了主动和被动鞭毛运动的波形，并在磁驱动细胞的情况下显示出明显的不对称性，导致所采取的通路的线性度较低 (LIN = VSL / VCL)。对于活跃的鞭毛，鞭毛节拍周期的平均曲率是 10.4 ± 8.1 rad mm−1 (mean ± s . d .)，而被动鞭毛的曲率表现出线性增加（37.4 ± 18.1 rad mm-1）并向远端减小。我们还表明弯曲波的最大振幅发生在主动鞭毛的远端和被动鞭毛的中间。我们的实验还显示了驱动场控制弯曲波沿着被动鞭毛的进展速度以匹配活动细胞的速度的能力。活动鞭毛通过传播弯曲波推动活动精子细胞。在这里，我们证明了非运动细胞具有被外部磁场无线驱动的能力，并揭示了对其推进特性的见解。通过基于静电的自组装实现了用纳米颗粒聚集体部分涂覆精子头部。该涂层能够在周期性磁场的作用下沿着被动鞭毛传播螺旋行波。我们比较了主动和被动鞭毛运动的波形，并在磁驱动细胞的情况下显示出明显的不对称性，导致所采取的通路的线性度较低 (LIN = VSL / VCL)。活动鞭毛的鞭毛搏动周期的平均曲率是 10.4 ± 8.1 rad mm−1 (mean ± s . d .)，而被动鞭毛的曲率呈线性增加 (37.4 ± 18.1 rad mm−1) 和向远端减小。我们还表明，弯曲波的最大振幅...... 我们比较了主动和被动鞭毛运动的波形，并在磁驱动细胞的情况下显示出明显的不对称性，导致所采取的通路的线性度较低 (LIN = VSL / VCL)。活动鞭毛的鞭毛搏动周期的平均曲率是 10.4 ± 8.1 rad mm−1 (mean ± s . d .)，而被动鞭毛的曲率呈线性增加 (37.4 ± 18.1 rad mm−1) 和向远端减小。我们还表明，弯曲波的最大振幅...... 我们比较了主动和被动鞭毛运动的波形，并在磁驱动细胞的情况下显示出明显的不对称性，导致所采取的通路的线性度较低 (LIN = VSL / VCL)。活动鞭毛的鞭毛搏动周期的平均曲率是 10.4 ± 8.1 rad mm−1 (mean ± s . d .)，而被动鞭毛的曲率呈线性增加 (37.4 ± 18.1 rad mm−1) 和向远端减小。我们还表明，弯曲波的最大振幅...... 1 rad mm-1) 并向远端减小。我们还表明，弯曲波的最大振幅...... 1 rad mm-1) 并向远端减小。我们还表明，弯曲波的最大振幅......