title: Micro-ring structures stabilize microdroplets to enable long term spheroid culture in 384 hanging drop array plates.
abstract: Using stereolithography, 20 different structural variations comprised of millimeter diameter holes surrounded by trenches, plateaus, or micro-ring structures were prepared and tested for their ability to stably hold arrays of microliter sized droplets within the structures over an extended period of time. The micro-ring structures were the most effective in stabilizing droplets against mechanical and chemical perturbations. After confirming the importance of micro-ring structures using rapid prototyping, we developed an injection molding tool for mass production of polystyrene 3D cell culture plates with an array of 384 such micro-ring surrounded through-hole structures. These newly designed and injection molded polystyrene 384 hanging drop array plates with micro-rings were stable and robust against mechanical perturbations as well as surface fouling-facilitated droplet spreading making them capable of long term cell spheroid culture of up to 22 days within the droplet array. This is a significant improvement over previously reported 384 hanging drop array plates which are susceptible to small mechanical shocks and could not reliably maintain hanging drops for longer than a few days. With enhanced droplet stability, the hanging drop array plates with micro-ring structures provide better platforms and open up new opportunities for high-throughput preparation of microscale 3D cell constructs for drug screening and cell analysis.
authors: Department of Biomedical Engineering, University of Michigan, 2215 Carl A Gerstacker Bldg, 2200 Bonisteel Blvd, Ann Arbor, MI 48109, USA.
authors: Amy Y
authors: AY
authors: Hsiao
authors: Yi-Chung
authors: YC
authors: Tung
authors: Chuan-Hsien
authors: CH
authors: Kuo
authors: Bobak
authors: B
authors: Mosadegh
authors: Rachel
authors: R
authors: Bedenis
authors: Kenneth J
authors: KJ
authors: Pienta
authors: Shuichi
authors: S
authors: Takayama
mesh_terms: D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods*; D045744:Cell Line, Tumor; D004867:Equipment Design; D057166:High-Throughput Screening Assays / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D018874:Spheroids, Cellular / Q000378:metabolism