Detection is one of the most critical—and often misunderstood—elements of capillary liquid chromatography. In this fifth installment of the Understanding Capillary LC lecture series, Dr. Sam Foster is joined by Dr. Purnendu K. (Sandy) Dasgupta to examine detector selection and performance at the capillary scale.
The session surveys commonly used detection approaches, including mass spectrometry, UV–Vis absorbance, fluorescence, refractometry, amperometry, conductance, and capacitively coupled contactless conductivity detection (C⁴D), with emphasis on why MS and UV remain the most widely adopted. Particular focus is placed on the sensitivity benefits of low-flow electrospray ionization for MS, as well as the inherent challenges of UV detection at short optical path lengths—and practical strategies to address them.
The discussion place attainable and typical limits of detection in context, connect optical, electrochemical, and mass-spectrometric principles to real-world capillary LC workflows, and conclude with practical considerations for interfacing capillary LC systems, including the Axcend platform, with MS and UV detectors.
Key Takeaways:
Purnendu K. (Sandy) Dasgupta, Ph.D.
Professor
University of Texas Arlington
Purnendu K. (Sandy) Dasgupta earned his BSc and MSc in Chemistry in India and his PhD in Analytical Chemistry (with a minor in Electrical Engineering) from LSU in 1977. After early work at LSU and UC Davis, he spent 25 years at Texas Tech before joining the University of Texas at Arlington, where he serves as the Hamish Small Chair in Ion Analysis. He has authored 450+ papers and book chapters and holds 46 patents, most of which have been licensed. Dr. Dasgupta’s work has been recognized with numerous honors, including the ACS National Awards in Analytical Chemistry, Chromatography, and Chemical Instrumentation, the Dal Nogare Award, Giddings Award, Talanta Medal, and the 2018 Texas Distinguished Scientist Award—the first Asian American to receive it. He is also a Fellow of the IEEE and was honored as a distinguished lecturer by UT Dallas chemistry students.
Samuel Foster, Ph.D.
Application Scientist
Axcend
Samuel Foster completed his Ph.D. in Pharmaceutical Chemistry from Rowan University in 2025. His research has focused on the development and application of capillary scale liquid chromatography instrumentation. He currently works at Axcend as an application scientist focusing on the development of chromatographic workflows for a variety of analyte classes including oligonucleotides, monoclonal antibodies, and drugs of abuse.