High-throughput culture and embedment of spheroid array using droplet contact-based spheroid transfer

Area of Science:

• Biotechnology
• 3D Cell Culture
• Microfluidics

Background:

• Spheroids are key 3D cell culture models, often formed via hanging drop methods.
• Conventional spheroid handling, including medium changes and hydrogel embedding, presents throughput limitations.
• Current methods rely on manual pipetting, which is time-consuming and prone to variability.

Purpose of the Study:

• To develop novel poly(dimethylsiloxane) (PDMS)-based devices for efficient spheroid manipulation.
• To overcome the bottlenecks associated with medium exchange and spheroid transfer in hanging drop cultures.
• To enable simultaneous embedding of spheroids into hydrogels, enhancing experimental throughput.

Main Methods:

• Utilized a drop array chip (DAC) with well structures for spheroid culture using the hanging drop method.
• Developed a droplet contact-based transfer mechanism for spheroid manipulation.
• Employed a PDMS-based pillar array chip (PAC) for simultaneous spheroid embedding into collagen hydrogels.
• Integrated DAC and PAC for efficient, non-manual spheroid transfer and embedding.

Main Results:

• Demonstrated successful repetitive medium changes and live/dead staining of spheroids using the DAC system.
• Achieved simultaneous embedding of spheroids into collagen hydrogel drops via DAC-PAC contact.
• The novel method significantly improved spheroid transfer and embedding efficiency compared to manual pipetting.
• Embedded spheroids exhibited reliable invasion behavior, comparable to conventionally embedded spheroids.

Conclusions:

• The developed PDMS devices offer a streamlined and efficient solution for spheroid culture and manipulation.
• The droplet contact-based transfer and simultaneous embedding methods significantly enhance experimental throughput.
• This technology holds promise for advancing 3D cell culture applications in drug discovery and tissue engineering.