He is a founding scientist and current director of 908 Devices incorporated, a company which focuses on building handheld mass spectrometry devices for applications in laboratory analysis, safety and security, as well as for use in the life sciences. In 2017 908 Devices Inc. received the Federal Laboratory Consortium Excellence in Technology Transfer Award. The company is known for several products, including the zipchip ™ separations platform for quick and high quality separation and mass spectrometry analysis of biological samples and the M908 ™ handheld High Pressure Mass Spectrometry tool for analysis of chemical warfare agents. Dr. Ramsey is also a founding scientist and former scientific advisory board member of Caliper Technologies incorporated, later renamed Caliper Life Sciences, a company that commercializes microfluidics and lab-on-a-chip technologies. Caliper Life Sciences was acquired by PerkinElmer in 2011 for $650M.
Between 1979 and 2004, Ramsey worked as a Eugene P. Wigner Fellow, research associate, and eventually a group leader for Oak Ridge National Laboratory.