From 1990 to 1992, Fassmann was a Josephine McCormick Postdoctoral Fellow at MITs Center for Analytic Chemistry, working with Volker Using et al. on soft ionization techniques, particularly electrospray ionization (ESI). This experience deeply influenced his later work on mass spectrometry.

Tue, 05 May 2026 20:56:58 +0000

**Why a Brief Chapter in Analytical Chemistry Shapes Modern Science — From 1990 to 1992** In the evolving landscape of scientific discovery, certain moments leave indelible marks—unheralded but foundational. Nowhere is this more evident than in the early 1990s, when a focused research period at MIT’s Center for Analytic Chemistry saw key breakthroughs in mass spectrometry. At the heart of this shift was Fassmann, a dedicated postdoctoral fellow working closely with Volker Using and leading-edge chemists on soft ionization techniques, especially electrospray ionization (ESI). Through meticulous experimentation, Fassmann helped refine methods that would revolutionize how molecules are detected and analyzed—especially large, fragile ones that resist traditional breakdown. Though not widely known outside specialized circles, this period signaled a turning point in biochemical mass analysis, laying critical groundwork for applications now central to biomedical research, pharmaceutical development, and forensic science. ---