I was born on 30 March, 1954 near the city of Chicago (USA). I received my primary and secondary education in the same area, but found the highly structured regime of a formal education intensely boring. I spent most of these years focused less on school than what at the time seemed trivial pursuits: photography, film processing, camping, car maintenance, helping to repair my parents’ house, and the like. What I did not appreciate at the time was that these activities were helping me to develop a strong curiosity about nature, physical laws, and mechanical devices. I started wondering why the grass was green, why the sky was blue, and how an automobile differential worked. None of the adults around me knew the answers to these questions, or even how to direct me to source material that would allow me to find it myself (now it's easy because all knowledge seems to be on the Web if you are willing to look hard enough).

By the time I entered high school, my oldest brother, Robert (now a critical care physician in California), was doing graduate research in biochemistry at the University of Illinois. Occasionally I visited him there, and when I did I felt a very strong sense of freedom and knowledge. I knew this was a place I wanted to be. There were a few roadblocks to overcome before that was to happen, however. One of the more tangible aspects of my boredom with high school was poor grades—below what was required to attend a good college like the University of Illinois. Fortunately, there was lots of good science not too far from my home at Argonne National Laboratory. I applied for a job there as a lab technician, interviewed (lied about my grades), and was given the job. My supervisor was a wonderful scientist named Ken Jensen. Kenny taught me everything there was to know about classical quantitative analysis. On the basis of my daily interactions with this outstanding role model, I developed an even stronger desire to be a scientist. Kenny encouraged me to apply to U. Illinois despite my lousy grades, and with a strong supporting letter from him (he was an alumnus) I was accepted into the College of Liberal Arts and Sciences. Back in the classroom I was again bored, but fortunately I signed up to take a separations science course from Prof. Larry R. Faulkner, and everything changed. Larry was a fantastic scientist and teacher, and he maintained a wonderful research group of young men and women who were truly dedicated to science (and having fun). Larry allowed me to do an undergraduate research project, which resulted in my first scientific publication. The paper was about an electrochemical study of the adsorption of molecules to mercury electrodes. I loved electrochemistry and was hooked for life. It was tough to leave this stimulating environment, but in 1981 I headed to the University of Texas for graduate school in chemistry with Prof. Allen J. Bard, the best electrochemist in the world.

I really didn't think science could get much better than my undergraduate experience, but once again I was in for a surprise. Al and his research group were truly inspiring. I worked on a project involving electrochemical studies in supercritical solvents, and with help from Al and a few other group members published the first papers in this new field. From Al, I learned how to think like a scientist (of the many gifts I received from my mentors, this was the most important), and I also learned there was consuming beauty in the science, that science was one of the most noble professions, and that the currency of science is integrity. Toward the end of my stay in Austin (I graduated with a Ph.D. in electrochemistry in 1987), I began reading papers authored by a professor at MIT name Mark S. Wrighton. These were like nothing I had seen before: the science involved integration of microelectronics (still a rather new field at the time) with electrochemistry, to yield a new type of chemical device that had applications to both sensing and electronics. By a remarkable coincidence, the postdoctoral fellow who was first author on many of these papers was a former Bard group graduate student named Henry S. White (now a professor of chemistry at University of Utah). I wrote to Mark and asked for a postdoctoral position in his group and much to my surprise he agreed.

Mark, his science, and the group members were truly amazing in ways that I shall never forget. I was in the group during one of its golden periods: everyone in the group was infected with Mark's enthusiasm and cleverness. I learned about conducting polymers and sensors during my stay at MIT. I also gained a new perspective on chemistry and the value of interdisciplinary research. I also learned about bad science and how poorly the general public and the popular press understands science: cold fusion happened in March, 1989, which was several months before I left MIT. The Wrighton group was one of the first to do a careful job of debunking cold fusion (although remarkably, a lot of people seem to still believe in it). Meanwhile, two subway stops away from MIT, in the laboratories of Prof. George Whitesides and his group at Harvard University, some really good science was going on. They were characterizing self-assembled n-alkylthiols on gold substrates. Surface-based molecular self-assembly had been discovered a few years earlier by Dave Allara and Ralph Nuzzo at Bell Labs, but I was not aware of it until friends at Harvard started telling me about their work. I took a special interest, because the concept of self-assembly seemed to lend itself to electrochemistry and chemical sensing, which were my two interests at the time.

In August 1989 I became an independent scientist for the first time when I accepted an assistant professorship at the University of New Mexico in Albuquerque. The University was poorly administered and the research infrastructure had been neglected, so it was difficult to do science there. However, when I arrived I was immediately befriended by a former Wrighton group member named Dr. Antonio J. Ricco who was working in the Microsensor R&D department at nearby Sandia National Laboratories. With help from Tony I obtained a small grant from Sandia that was intended to stimulate collaborations between the Lab and nearby universities. Working together, we began a series of experiments using self-assembled monolayers as chemically sensitive platforms for sensor applications. Whitesides and his colleagues had done such a thorough job of characterizing these materials that they were ripe for such applications. Thanks in part to our collaborative work, chemical sensing became one of the first uses of self-assembled monolayers. During this same period Tony and I demonstrated that it was possible to do chemistry on the distal end of self-assembled monolayers using gas-phase reactions. This was also an important discovery, and many scientists now use this approach routinely for building nanostructures of various sorts.

Another outstanding Sandia scientist I had the opportunity to work with during my time in New Mexico was Dr. C. Jeffrey Brinker. Jeff was one of the world's foremost experts in the field of sol-gel chemistry, and he introduced me to the concept of using self-assembled three-dimensional templates to prepare nanomaterials. In the very early 1990s we co-authored a series of papers showing that interstices between sol-gel derived materials could be used as templates to prepare semiconductor nanomaterials. I think these papers have been largely forgotten during the current extreme interest in the synthesis and characterization of nanomaterials, but the fact is they were among the first examples of using self-assembled templates to make nanomaterials.

I worked with one other Sandian: Dr. Jack Houston. This was my first close collaboration with a physicist, and it was great. Jack and his coworkers had invented a new measuring device he called the interfacial force microscope (IFM). It was a little like an atomic force microscope, but instead of the force sensor being based on a cantilever it was based on a teeter-totter. The IFM was ideally suited for measuring the forces between chemically functionalized surfaces. The problem Jack faced was that the first-generation IFM was not ready to install in a UHV chamber. Coming from the UHV surface science community, Jack believed that all surfaces at pressures above 10^-10 torr were so dirty they weren't worth studying. However, like all good scientists, he had an open mind. Together, we began using his IFM to study the chemistry of self-assembled monolayers. This was a very productive set of experiments, and I think the resulting papers helped to get both the chemistry and physics communities thinking about the molecular basis of adhesion.

Unfortunately, administrative politics at that time was chewing around the edges of all this wonderful collaborative science. I had no idea that the politics of science could be so distracting, but one by one, my colleagues in the chemistry department departed for positions elsewhere. In 1993, I accepted the position of associate professor (with tenure!) at Texas A&M University.

What a difference between the research environment and infrastructures at Texas A&M and New Mexico! Not only was I back in Texas, which I had become attached to during my time in Austin with Prof. Bard, but I was surrounded by wonderful colleagues and outstanding resources. During the group's nine years at Texas A&M, we have drawn from our earlier experience to prepare more advanced self-assembled structures for chemical sensing applications. We also showed that larger molecules, dendrimers for example, could also form something akin to self-assembled monolayers on surfaces, and that these materials had especially interesting properties for chemical sensing. Likewise, we found that dendrimers contained within alkylthiol self-assembled monolayers act as passive or active gates for small molecule transport. Together with my Texas A&M colleague Prof. David Bergbreiter, we demonstrated that patterned self-assembled monolayers could be used as templates for subsequent polymer growth. Later we showed that such materials could themselves template the growth of mammalian and bacterial cells. One of our most important discoveries in recent years was that dendrimers could be used as templates to self assemble metal and semiconductor nanoparticle replicas. These dendrimer/nanoparticle composites are remarkable in many ways, but their catalytic and optical properties are of special interest.

During the last year or so, my group has become interested in doing chemistry within microfluidic systems. My interest in this area was stimulated by conversations with Prof. Bard during one of our joint group meetings (of the many advantages of living in Texas, one of the best is that I am still able to interact with the Bard group face-to-face). Bard wrote a book some time ago called Integrated Chemical Systems. This book provides a vision for combining different chemistries into integrated systems that perform complex functions. I believe that microfluidic systems provide a very good platform for realizing this vision, and the results my group have obtained during the last year have gone a long way toward reinforcing this perspective. Thus far, molecular self-assembly has not played a major role in our microchemistry studies, but I believe that as we learn more about doing chemistry in picoliter volumes, we will find that the high surface-area-to-volume ratios in such small containers lends itself to modification with self-assembled structures. Of course our work with self-assembled monolayers and related materials continues in ever-more sophisticated directions (often still in collaboration with our friends at Sandia). For example, we are trying to use individual dendrimers as "nanofilters" to selectively pass molecules into nanoscopic beakers. This is a tough experiment, but I think we'll get it to work before the end of the year. A new project, which we are carrying out in collaboration with Prof. Eric Simanek at Texas A&M and Prof. Robert M. Corn at the University of Wisconsin, involves attaching DNA to dendrimers in an effort to coax the dendrimers into self-assembled, three-dimensional structures. We've just sent in our first research paper in this area, and the results are encouraging (but much remains to be done).

As I get older and more frequently contemplate the meaning of life, I am beginning to think that we are here mainly to try to understand that which surrounds us. The study of science, and chemistry in particular, is a wonderful basis for doing that. I find it amazing that someone is willing to pay me to spend my time doing science and interacting with really smart and engaging colleagues and students. I have to thank my mentors, Kenny Jensen, Larry Faulkner, Al Bard, and Mark Wrighton for all that they have given me. I also want to express heartfelt thanks to all my collaborators, but especially Tony Ricco, Jeff Brinker, Jack Houston, and Dave Bergbreiter who have taught me much about science and being a scientist. Finally, I have had the privilege to work with some really remarkable students and postdocs over the years, most of whom have gone on to make their own mark in industry or academic science. One person in particular, Dr. Li Sun, has been involved in our self-assembly work from the beginning, and his insight has been a constant source of inspiration for me for more than a decade.

Richard M. Crooks, Ph.D.
Texas A&M University
Department of Chemistry
College Station, Texas, USA