title: Magnetic force-assisted self-locking metallic bead array for fabrication of diverse concave microwell geometries.
abstract: Spheroid cell culture is very useful for further understanding cellular behavior including motility and biochemical reaction since it mimics three-dimensional (3D) in vivo organ tissue. Among previously proposed various methods for spheroid production, such as hanging drop and spinner flask, microwell is a recently developed method harnessing microtechnology to produce uniform-sized spheroids. Although soft-lithography has been popular for creating microwell arrays, a 3D spherical geometry has been regarded as difficult to fabricate using conventional methods, or often requires complex fabrication processes and expensive equipment. Here, we propose a new method for fabricating concave microwells for cell spheroid production and culture. To demonstrate this method, we fabricated a 30 × 30 microwell array in 3 × 3 cm plates, utilizing metal beads, a through-hole array, and an assembly of small magnets. The spherical metal beads were used as a mold for the microwell, naturally creating the desired 3D concave microwell geometry. One of the key ideas was to place and hold each metal bead in the designated through-hole using the small magnet array. We also performed computational simulation of the magnetostatic force to design and observe the magnetic force field in detail. In addition, to provide a practical demonstration of the proposed system in cell biology, we created and cultured adipose-derived stem cell spheroids for 14 days for chondrogenic differentiation. This method allows further variations in microwell geometry that will enhance the method's applicability as a helpful tool for various studies in cell biology, cancer research, and tissue engineering.
authors: School of Mechanical Engineering, College of Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea. jrpark@cau.ac.kr.
authors: Gi-Hun
authors: GH
authors: Lee
authors: Ye Eun
authors: YE
authors: Park
authors: Minhaeng
authors: M
authors: Cho
authors: Hansoo
authors: H
authors: Park
authors: Joong Yull
authors: JY
authors: Park
mesh_terms: D000273:Adipose Tissue / Q000166:cytology; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D020219:Chondrogenesis; D006801:Humans; D060328:Magnetic Phenomena; D008670:Metals / Q000737:chemistry*; D008863:Microspheres; D013234:Stem Cells / Q000166:cytology; D046888:Tissue Array Analysis / Q000295:instrumentation*
chemical_list: D008670:Metals