Automated, Ultra-Sterile Solid Sample Handling and Analysis on a Chip

NASA’s Jet Propulsion Laboratory, Pasadena, California

There are no existing ultra-sterile lab-on- a-chip systems that can accept solid samples and perform complete chemical analyses without human intervention. The proposed solution is to demonstrate completely automated lab-on- a-chip manipulation of powdered solid samples, followed by on-chip liquid extraction and chemical analysis.

(A) Manipulation of a **Solid Sample On-Chip,** and (B) mixing of fluid and solid sample on-chip. Each photograph is approximately 4×1 cm in size.

This technology utilizes a newly invented glass micro-device for solid manipulation, which mates with existing lab-on-a-chip instrumentation. Devices are fabricated in a Class 10 cleanroom at the JPL MicroDevices Lab, and are plasma- cleaned before and after assembly. Solid samples enter the device through a drilled hole in the top. Existing micropumping technology is used to transfer milligrams of powdered sample into an extraction chamber where it is mixed with liquids to extract organic material. Subsequent chemical analysis is performed using portable microchip capillary electrophoresis systems (CE). These instruments have been used for ultrahighly sensitive (parts-per-trillion, pptr) analysis of organic compounds including amines, amino acids, aldehydes, ketones, carboxylic acids, and thiols. Fully autonomous amino acid analyses in liquids were demonstrated; however, to date there have been no reports of completely automated analysis of solid samples on chip.

This approach utilizes an existing portable instrument that houses optics, high-voltage power supplies, and solenoids for fully autonomous microfluidic sample processing and ..CE analysis with laser-induced fluorescence (LIF) detection. Furthermore, the entire system can be sterilized and placed in a cleanroom environment for analyzing samples returned from extraterrestrial targets, if desired.

This is an entirely new capability never demonstrated before. The ability to manipulate solid samples, coupled with lab-on-a-chip analysis technology, will enable ultraclean and ultrasensitive endto- end analysis of samples that is orders of magnitude more sensitive than the ppb goal given in the Science Instruments, Observatories, and Sensor Systems Roadmap. This technology has potential applications for highly sensitive analyses of organic compounds elsewhere in the solar system, including Mars, Europa, Titan, and small bodies. It will also enable contamination-free analysis of returned samples. Finally, this could also be employed for a wide range of terrestrial applications including environmental, biomedical, or forensic analyses.

This work was done by Maria F. Mora, Amanda M. Stockton, and Peter A. Willis of Caltech for NASA’s Jet Propulsion Laboratory. NPO-48603