In the quest to address infertility, Cornell researchers have developed a groundbreaking device that could simplify and automate oocyte cumulus removal, a critical step in assisted reproductive technologies.
Their vibration-powered chip not only simplifies a complex procedure but also extends it to areas of the world lacking skilled embryologists or well-funded labs, reducing overall costs. This offers hope to millions of couples struggling with infertility - and makes fertility treatments more accessible worldwide.
"This platform is a potential game-changer," said Alireza Abbaspourrad, associate professor of food chemistry and ingredient technology in food science in the College of Agriculture and Life Sciences (CALS). "It reduces the need for skilled technicians, minimizes contamination risks and ensures consistent results - all while being portable and cost-effective."
He is co-author of "On-Chip Oocyte Cumulus Removal using Vibration Induced Flow," published Sept. 5 in the journal Lab on a Chip.
Doctors treating infertility need to do a critical step: gently separate protective cumulus cells from oocytes, the developing egg cells. The process, known as cumulus removal (CR), is essential for evaluating oocyte maturity before spermatozoon injection, or ensuring successful fertilization after insemination in vitro fertilization (IVF).
Traditionally, CR relies on manual pipetting: by flushing the single oocyte repeatedly with a micropipette, cumulus cells are detached from the oocyte. However, the technique demands precision, expertise and significant time. Errors can lead to damaged oocytes or failed fertilization, making the procedure a delicate and labor-intensive task.
The team's innovation: a disposable, open-surface chip that uses vibrations, which they call vibration-induced flow, to automate CR. The chip features a spiral array of micropillars that create a whirling flow when vibrated, separating smaller cumulus cells from larger oocytes.
"The process is fast, efficient, noninvasive and more consistent, while reducing manual labor and preserving embryo development outcomes," said Amirhossein Favakeh, a doctoral candidate in Abbaspourrad's lab and a co-author of the study. "The oocytes remain safely in the loading chamber, while the cumulus cells are swept into an adjacent collection well."
The researchers tested the device on mouse oocytes, which share genetic similarities with human eggs. They optimized the system by adjusting vibration power, exposure time and enzyme concentration. They found that the platform could denude up to 23 oocytes simultaneously without any loss or damage. Even freeze-thawed oocytes, which are typically more fragile, were successfully processed.
To ensure the safety of the technique, the team compared fertilization and embryo development rates between oocytes denuded manually and those treated with vibration induced flow. The results were nearly identical: fertilization rates were 90.7% for manual pipetting and 93.1% for vibration induced flow, while the rate of formation of blastocysts, balls of cells formed early in a pregnancy, were 50.0% and 43.1%, respectively.
"This shows that our method doesn't compromise the developmental potential of the oocytes," Abbaspourrad said.
The implications of this technology extend far beyond fertility clinics. The chip's ability to separate particles of different sizes could be applied to other biomedical fields, such as cancer cell isolation or microfluidic research. Its low cost and ease of use make it particularly appealing for regions with limited access to advanced medical facilities.
Favakeh said this approach has the potential to democratize access to fertility treatment by reducing the reliance on expensive equipment and highly trained embryologists, which might allow these procedures to be brought to underserved areas.
"Ordinarily, the whole process is costly and delicate; clinics invest a lot of time in training and it is very dependent on human resources," Abbaspourrad said. "With this, you don't need a highly trained human to do it. And what is really important is there is almost no chance of damaging or losing the cell."
The team plans to expand their research to include human oocytes and explore applications in intracytoplasmic sperm injection, in which CR is performed prior to fertilization. They also aim to refine the chip's design for broader use in cell manipulation and sorting.
For now, the Cornell scientists are celebrating a major step forward in assisted reproductive technologies, they said.
This is a small device with a big impact, Abbaspourrad said.
"Replacing tedious manual methods with a simple vibration-based chip improves the speed, safety and consistency of oocyte preparation," he said, "making fertility treatments more accessible and reliable."
Co-authors include Amir Mokhtare, a postdoctoral fellow in Abbaspourrad's lab; Yi Athena Ren, assistant professor of reproductive biology in animal science (CALS); and Hanxue Zhang, a postdoctoral associate in Ren's lab.
