In Memory of Walton Caldwell, a Pioneer in SFC
Today, I learned of the passing of a dear friend and a valued collaborator, Walton Caldwell, who founded the company Princeton Chromatography in 1994.
Today, I learned of the passing of a dear friend and a valued collaborator, Walton Caldwell, who founded the company Princeton Chromatography in 1994.
I knew Walt for nearly 20 years, and even though we were separated by ~3000 miles, every time we spoke, albeit by telephone, it felt as if we were neighbors. We would catch up on business and our families and then get down to the science, which was our common passion. After every call, I was excited by the half dozen ideas we had just discussed and looked forward to the one or two projects we decided to pursue together-usually developing and testing new supercritical fluid chromatography (SFC) columns. I think he and I operated in a similar fashion: We liked to try new ideas and test new directions, out of pure curiosity of where it would lead us next. I think that curiosity is the source of the impact that Walt has had on the scientific community: Many of the new column chemistries that Princeton Chromatography developed were derived from Walt’s using his openness to explore new ideas, mixed with his skill and creativity in bringing them to fruition.
Some of my best memories of Walt are openly debating the state of the art (or lack thereof) of column phases at an SFC conference, sitting with him and Jeff Caldwell (his son) at their booth at Pittcon, and especially the time I took a tour of their facility in Cranbury, New Jersey. The excitement Walt displayed on that tour was the same as the thrill he expressed whenever his (then) prototype columns generated positive data. Walt had a passion and curiosity for science and SFC, and in particular for developing columns to advance the field of SFC. In my mind, and I’m sure in the minds of all who knew him, Walton Caldwell will be remembered as a true pioneer in the field of SFC.
William Farrell is an Associate Research Fellow at Pfizer Global R&D in La Jolla, California
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