Measurement of Interfacial Adhesion Force with a 3D-Printed Fiber-Tip Microforce Sensor

Abstract

With the current trend of device miniaturization, the measurement and control of interfacial adhesion forces are increasingly important in fields such as biomechanics and cell biology. However, conventional fiber optic force sensors with high Young’s modulus (>70 GPa) are usually unable to measure adhesion forces on the micro- or nano-Newton level on the surface of micro/nanoscale structures. Here, we demonstrate a method for interfacial adhesion force measurement in micro/nanoscale structures using a fiber-tip microforce sensor (FTMS). The FTMS, with microforce sensitivity of 1.05 nm/μN and force resolution of up to 19 nN, is fabricated using femtosecond laser two-photon polymerization nanolithography to program a clamped-beam probe on the end face of a single-mode fiber. As a typical verification test, the micronewton-level contact and noncontact adhesion forces on the surfaces of hydrogels were measured by FTMS. In addition, the noncontact adhesion of human hair was successfully measured with the sensor.

Femtosecond Laser 3D Nano‐Printing for Functionalization of Optical Fiber Tips

“…This structure has been used to measure properties like Young's modulus, contact force, non-contact adhesion of hydrogel surfaces, and in vivo tissue characteristics. [174,205,206] For gas pressure sensing, multilayer F-P interferometers have been developed by Wei et al, demonstrating a sensitivity of 3.959 nm MPa −1 in the range of 0-1100kPa. [207] Furthermore, FL-3DNp technology holds the potential for manufacturing more precise gas pressure sensing devices.…”

“…This structure has been used to measure properties like Young's modulus, contact force, non‐contact adhesion of hydrogel surfaces, and in vivo tissue characteristics. [ 174,205,206 ]…”

Progress in Probe-Based Sensing Techniques for In Vivo Diagnosis

“…With the continuous miniaturization of surgical instruments, force sensors based on micro or nanostructures have gradually become a research hotspot. Zou et al proposed a Fabry–Perot-based nanonewton-scale force sensor, which was printed on a single-mode fiber tip to measure the adhesion forces applied on the surfaces of micro/nanoscale structures [ 53 ]. A combination of multiple manufacturing methods can provide a possible for complex microstructure to sensing.…”

Microstructured Cantilever Probe on Optical Fiber Tip for Microforce Sensor

“…The two-photon polymerization (TPP) can directly add materials to print various complex micro-nano structures on the fiber substrate, effectively realize the precise integration of the microcantilever beam and optical fiber, and make it possible to combine the MEMS technology with the optical fiber sensing technology [25][26][27]. In the previous work, based on most of the research, the structure designed and prepared has always remained in the common rectangular shape [28][29][30]. Therefore, the flexible design of the cantilever probe structure and the unique mechanical properties of the structure given by 3D printing have not been deeply explored.…”