Three-dimensional silicon-micromachined microbiopsy tool and in-vivo experiment

A three-dimensional array of single-crystalline silicon microspikes with protruded barbs is developed for microscale biopsy. The developed microbiopsy tool is designed to replace the conventional endoscopic biopsy tool and to reduce patient discomfort and risk during the endoscopic operation. For fabrication we extend the SBM (Sacrificial Bulk Micromachining) process and apply the SBM process to both sides of the wafer. Shanks of the fabricated 3D microspikes are 1.5 mm long, 150 μm thick and 150 μm wide. The developed microbiopsy tools are evaluated in-vivo experiment by extracting tissues from live anesthetized rabbits and examining the tissue with the hematoxylin and eosin (H&E) staining protocol. In addition, the clinical test of extracting gastric adenocarcinoma tissue samples is also performed. The 3D microspikes successfully extracted tissue samples from the small intestines of the anesthetized rabbits and gastric adenocarcinoma tissue. The evaluation reveals that the biopsy with the 3D microspike can be applied to the medical examination.