Mike Ramsey

The Ramsey group is interested in developing micro- and nanofabrication strategies to create devices that facilitate high-throughput biochemical experimentation, development of chemical sensors, and understanding of transport mechanisms in nanoscale-confined spaces. These devices have a wide range of applications in the areas of drug discovery, health care, environmental monitoring, and basic research.

Microfluidics-
Many of the lab’s projects involve microfabrication of fluidic networks that are used to perform biochemical assays. This area of research is often referred to as microfluidics, microchips, or Lab-on-a-Chip technology. The Ramsey group is currently developing microfluidic devices for proteomics applications and automated single-cell assays. Conventional proteomics technologies require milligram quantities of protein and chemical separations that unfold over a period of days. The Ramsey group is applying microfabricated fluidics approaches to implement multidimensional liquid-phase separations that use nanogram to picogram quantities of material with separations unfolding over a period of tens of minutes. The ability to perform electrospray ionization from microchips is also being developed to allow structural analysis via mass spectrometry of the isolated proteins.

Microfluidics devices are also being developed to manipulate single non-adherent cells, characterize them using flow cytometry techniques, lyse the cells, and analyze their contents. This automated approach allows high-throughput biochemical characterization at the single-cell level. Through a collaboration with Nancy Allbritton (UC Irvine), multiple kinase assays are being performed using such devices to study signal-transduction pathways. Moreover, collaborations with Andrew Green (Medical College of Wisconsin) and Lloyd Smith (University of Wisconsin) are underway to perform proteome studies on single cells.

Nanofluidics-
The Ramsey group is also interested in molecular transport through conduits with nanoscale dimensions, referred to as nanofluidics. They are studying both fluid and polymer transport through individual nanoscale conduits or pores fabricated using top-down methods with hard materials such as glass, quartz or silicon. Attempts to further reduce lateral dimensions of channels and pores will use bottom-up strategies and interface molecular assemblies to features formed in hard materials. While this work is fundamental, it could lead to new methods for the separation and analysis of polymeric materials, new types of chemical sensors, or technology that allows the structure of single-polymer molecules to be determined (e.g., single-molecule DNA sequencing).

Selected publications:
Pau S, Pai CS, Low YL, Moxom J, Reilly PT, Whitten WB, Ramsey JM. (2006) Microfabricated quadrupole ion trap for mass spectrometer applications. Phys Rev Lett. 96:120801.

Culbertson CT, Tugnawat Y, Meyer AR, Roman GT, Ramsey JM, Gonda SR. (2005) Microchip separations in reduced-gravity and hypergravity environments. Anal Chem. 77:7933-40.

Liu Y, Foote RS, Jacobson SC, Ramsey JM. (2005) Stacking due to ionic transport number mismatch during sample sweeping on microchips. Lab Chip. 5:457-65.

Poulsen CR, Culbertson CT, Jacobson SC, and Ramsey JM (2005) Static and dynamic acute cytotoxicity assays on microfluidic devices. Anal Chem 77:667-672.

Foote RS, Khandurina J, Jacobson SC, and Ramsey JM (2005) Microfabricated porous membrane structure for sample concentration and electrophoretic analysis. Anal Chem 77:57-63.

Ramsey JD, Jacobson SC, Culbertson CT, and Ramsey JM (2003) High-efficiency, two-dimensional separations of protein digests on microfluidic devices. Anal Chem 75:3758-3764.

McClain MA, Culbertson CT, Jacobson SC, Allbritton NL, Sims CE, and Ramsey JM (2003) Microfluidic devices for the high-throughput chemical analysis of cells. Anal Chem 75:5646-5655.







					The Ramsey group is interested in developing micro- and nanofabrication strategies to create devices that facilitate high-throughput biochemical experimentation, development of chemical sensors, and understanding of transport mechanisms in nanoscale-confined spaces. These devices have a wide range of applications in the areas of drug discovery, health care, environmental monitoring, and basic research. Microfluidics- Many of the lab’s projects involve microfabrication of fluidic networks that are used to perform biochemical assays. This area of research is often referred to as microfluidics, microchips, or Lab-on-a-Chip technology. The Ramsey group is currently developing microfluidic devices for proteomics applications and automated single-cell assays. Conventional proteomics technologies require milligram quantities of protein and chemical separations that unfold over a period of days. The Ramsey group is applying microfabricated fluidics approaches to implement multidimensional liquid-phase separations that use nanogram to picogram quantities of material with separations unfolding over a period of tens of minutes. The ability to perform electrospray ionization from microchips is also being developed to allow structural analysis via mass spectrometry of the isolated proteins. Microfluidics devices are also being developed to manipulate single non-adherent cells, characterize them using flow cytometry techniques, lyse the cells, and analyze their contents. This automated approach allows high-throughput biochemical characterization at the single-cell level. Through a collaboration with Nancy Allbritton (UC Irvine), multiple kinase assays are being performed using such devices to study signal-transduction pathways. Moreover, collaborations with Andrew Green (Medical College of Wisconsin) and Lloyd Smith (University of Wisconsin) are underway to perform proteome studies on single cells. Nanofluidics- The Ramsey group is also interested in molecular transport through conduits with nanoscale dimensions, referred to as nanofluidics. They are studying both fluid and polymer transport through individual nanoscale conduits or pores fabricated using top-down methods with hard materials such as glass, quartz or silicon. Attempts to further reduce lateral dimensions of channels and pores will use bottom-up strategies and interface molecular assemblies to features formed in hard materials. While this work is fundamental, it could lead to new methods for the separation and analysis of polymeric materials, new types of chemical sensors, or technology that allows the structure of single-polymer molecules to be determined (e.g., single-molecule DNA sequencing). Selected publications: Pau S, Pai CS, Low YL, Moxom J, Reilly PT, Whitten WB, Ramsey JM. (2006) Microfabricated quadrupole ion trap for mass spectrometer applications. Phys Rev Lett. 96:120801. Culbertson CT, Tugnawat Y, Meyer AR, Roman GT, Ramsey JM, Gonda SR. (2005) Microchip separations in reduced-gravity and hypergravity environments. Anal Chem. 77:7933-40. Liu Y, Foote RS, Jacobson SC, Ramsey JM. (2005) Stacking due to ionic transport number mismatch during sample sweeping on microchips. Lab Chip. 5:457-65. Poulsen CR, Culbertson CT, Jacobson SC, and Ramsey JM (2005) Static and dynamic acute cytotoxicity assays on microfluidic devices. Anal Chem 77:667-672. Foote RS, Khandurina J, Jacobson SC, and Ramsey JM (2005) Microfabricated porous membrane structure for sample concentration and electrophoretic analysis. Anal Chem 77:57-63. Ramsey JD, Jacobson SC, Culbertson CT, and Ramsey JM (2003) High-efficiency, two-dimensional separations of protein digests on microfluidic devices. Anal Chem 75:3758-3764. McClain MA, Culbertson CT, Jacobson SC, Allbritton NL, Sims CE, and Ramsey JM (2003) Microfluidic devices for the high-throughput chemical analysis of cells. Anal Chem 75:5646-5655. back to top



		contact information: [phone] (919) 962-7492 [email]