Micromanipulation and biological, material science, and medical applications often require to control or measure the forces asserted on small objects. Here, we demonstrate for the first time the microprinting of a novel fiber-tip-polymer clamped-beam probe micro-force sensor for the examination of biological samples. The proposed sensor consists of two bases, a clamped beam, and a force-sensing probe, which were developed using a femtosecond-laser-induced two-photon polymerization (TPP) technique. Based on the finite element method (FEM), the static performance of the structure was simulated to provide the basis for the structural design. A miniature all-fiber micro-force sensor of this type exhibited an ultrahigh force sensitivity of 1.51 nm μN⁻¹, a detection limit of 54.9 nN, and an unambiguous sensor measurement range of ~2.9 mN. The Young’s modulus of polydimethylsiloxane, a butterfly feeler, and human hair were successfully measured with the proposed sensor. To the best of our knowledge, this fiber sensor has the smallest force-detection limit in direct contact mode reported to date, comparable to that of an atomic force microscope (AFM). This approach opens new avenues towards the realization of small-footprint AFMs that could be easily adapted for use in outside specialized laboratories. As such, we believe that this device will be beneficial for high-precision biomedical and material science examination, and the proposed fabrication method provides a new route for the next generation of research on complex fiber-integrated polymer devices.

显微操作和生物、材料科学和医学应用通常需要控制或测量施加在小物体上的力。在这里，我们首次展示了用于检查生物样品的新型纤维尖端聚合物夹束探针微力传感器的微打印。所提出的传感器由两个底座、一个夹紧梁和一个力传感探头组成，它们是使用飞秒激光诱导双光子聚合 (TPP) 技术开发的。基于有限元法（FEM）对结构的静态性能进行模拟，为结构设计提供依据。这种类型的微型全纤维微力传感器表现出1.51 nm μN ^-1的超高力灵敏度，检测限为 54.9 nN，明确的传感器测量范围为 ~2.9 mN。使用所提出的传感器成功测量了聚二甲基硅氧烷、蝴蝶触角和人类头发的杨氏模量。据我们所知，该光纤传感器在迄今为止报道的直接接触模式下具有最小的力检测极限，可与原子力显微镜 (AFM) 相媲美。这种方法为实现小尺寸原子力显微镜开辟了新的途径，可以很容易地适应外部专业实验室的使用。因此，我们相信该器件将有利于高精度生物医学和材料科学检测，所提出的制造方法为下一代复杂纤维集成聚合物器件的研究提供了新途径。