Potomac is excited to work on increasingly innovative applications of microfluidics technology as we push the envelope of advanced manufacturing capabilities.  These so-called “Lab on a Chip” devices have miniaturized diagnostics to a point where affordable testing allows for highly specific research.  For example, a team in the Gerecht Lab in the Dept. of Chemical and Biomolecular Engineering at the Johns Hopkins University [JHU] Institute for NanoBioTechnology uses microfluidics to research cancer diagnostics in novel ways.

 

Daniel Lewis, a Ph.D. Candidate in the group, explains that hypoxia, a condition in which a tumor is deprived of adequate oxygen supply, is a critical factor in the progression and metastasis of many cancers, including soft tissue sarcomas.  This group of malignant cancers such as Kaposi’s Sarcoma, which affects patients infected with the AIDS virus, generates approximately 13,000 new cases per year in the United States alone, with 25–50% of patients developing recurrent and metastatic disease. Current clinical data suggest that undifferentiated pleomorphic sarcoma (UPS) is one of the most aggressive sarcoma subtypes, which frequently results in lethal pulmonary metastases that are insensitive to radio/chemotherapy.

 

Since oxygen gradients frequently develop in tumors as they grow beyond their vascular supply, leading to heterogeneous areas of oxygen depletion, Daniel’s work centers on understanding how oxygen gradients regulate early stages of tumor metastasis. He describes the research: “Leveraging an oxygen-controlling hydrogel, we generated a 3D in vitro model that enables us to analyze cancer cell responses to oxygen gradients and small-molecule inhibitors. Using this approach, we present a previously unidentified concept in which oxygen acts as a 3D physicotactic agent during sarcoma tumor invasion, findings that are important for the understanding of the metastatic process. Through this concept, we also establish the 3D in vitro model as a platform for testing therapeutic targets and interventions for the treatment of sarcoma and potentially, other cancers.”

 

In creating new microfluidic devices, Daniel wanted to turn to PMMA, a non-permeable material that the team expected would provide better control of oxygen tension and concentration.  The school’s onsite machine shop could not provide the micro-machining precision and resolution needed for the delicate task.  “Traditional machining leaves tool marks,” says Daniel.  “These ridges could be as large as 500 nm, which greatly affect the small-sized cells in our sample.  Also acrylic becomes cloudy when machined so we needed a more sophisticated fabrication solution.”

 

Potomac was able to easily meet Daniel’s 175 – 250 micron channel width specification in PMMA utilizing micro-CNC technology developed for the medical device and biotech industries.  With an array of tools in-house, we can go to the right tool for a specific job.  Laser micromachining, for example, can produce microfluidic channels as small as 10 microns wide and deep.  In this case, micro-CNC made the most sense for the channel size and provided the smooth surface finish that the team needed.

We’re always thrilled to bring advanced manufacturing skills to research such as cancer diagnostics and treatment.  While we love all of the tools we work with on a daily basis, the real satisfaction comes from how our advanced manufacturing machines improve and sometimes, even save, lives.

 

Read more details on Potomac’s Fast Track microfluidic device program for economical, quick-turnaround