Stanford Advisors

All Publications

  • Ratiometric Sensing of Redox Environments Inside Individual Carboxysomes Trapped in Solution. The journal of physical chemistry letters Carpenter, W. B., Lavania, A. A., Borden, J. S., Oltrogge, L. M., Perez, D., Dahlberg, P. D., Savage, D. F., Moerner, W. E. 2022: 4455-4462


    Diffusion of biological nanoparticles in solution impedes our ability to continuously monitor individual particles and measure their physical and chemical properties. To overcome this, we previously developed the interferometric scattering anti-Brownian electrokinetic (ISABEL) trap, which uses scattering to localize a particle and applies electrokinetic forces that counteract Brownian motion, thus enabling extended observation. Here we present an improved ISABEL trap that incorporates a near-infrared scatter illumination beam and rapidly interleaves 405 and 488 nm fluorescence excitation reporter beams. With the ISABEL trap, we monitored the internal redox environment of individual carboxysomes labeled with the ratiometric redox reporter roGFP2. Carboxysomes widely vary in scattering contrast (reporting on size) and redox-dependent ratiometric fluorescence. Furthermore, we used redox sensing to explore the chemical kinetics within intact carboxysomes, where bulk measurements may contain unwanted contributions from aggregates or interfering fluorescent proteins. Overall, we demonstrate the ISABEL trap's ability to sensitively monitor nanoscale biological objects, enabling new experiments on these systems.

    View details for DOI 10.1021/acs.jpclett.2c00782

    View details for PubMedID 35549289

  • Characterizing physical properties of single carboxysomes in the Interferometric Scattering Anti-Brownian ELectrokinetic trap Lavania, A. A., Carpenter, W. B., Oltrogge, L. M., Borden, J., Perez, D. D., Squires, A. H., Dahlberg, P. D., Savage, D. F., Moerner, W. E. CELL PRESS. 2022: 431A
  • Redox sensing inside individual carboxysomes in the ISABEL trap Carpenter, W. B., Borden, J., Oltrogge, L. M., Lavania, A., Perez, D., Dahlberg, P. D., Savage, D., Moerner, W. E. CELL PRESS. 2022: 104