Colin P. McCoy

Bio: Colin P. McCoy is an academic researcher from Queen's University Belfast. The author has contributed to research in topics: Self-healing hydrogels & Drug delivery. The author has an hindex of 32, co-authored 103 publications receiving 10824 citations. Previous affiliations of Colin P. McCoy include Queen's University.

A molecular photoionic AND gate based on fluorescent signalling

Abstract: MOLECULES that perform logic operations are prerequisites for molecular information processing and computation1–11. We12,13 and others14–16 have previously reported receptor molecules that can be considered to perform simple logic operations by coupling ionic bonding or more complex molecular-recognition processes with photonic (fluorescence) signals: in these systems, chemical binding (the 'input') results in a change in fluorescence intensity (the 'output') from the receptor. Here we describe a receptor (molecule (1) in Fig. 1) that operates as a logic device with two input channels: the fluorescence signal depends on whether the molecule binds hydrogen ions, sodium ions or both. The input/output characteristics of this molecular device correspond to those of an AND gate.

Fluorescent PET (photoinduced electron transfer) sensors

Abstract: Fluorescent PET (photoinduced electron transfer) sensors are considered to be those molecular systems where the binding of ions and other species leads to the perturbation of the competition between the de-excitation pathways of fluorescence and electron transfer. The early developments in this field are traced and the design logic of these sensors is detailed. A variety of examples drawn from different areas of chemistry are classified according to the ‘fluorophore-spacer-receptor’ format and their photophysical behaviour is rationalized in terms of fluorescent PET sensor principles. Cases are pointed out where such experimental data are unavailable but desirable. During these discussions, the relevance of twisted fluorophore-receptor systems and the contrast with integrated fluorophore-receptor systems is noted. The utility of the fluorescence ‘on-off’ phenomenon in these PET sensors for the area of molecular photoionic devices is pointed out.

New Fluorescent Model Compounds for the Study of Photoinduced Electron Transfer: The Influence of a Molecular Electric Field in the Excited State

Abstract: The location of the “spacer–receptor” unit in a 4-aminonaphthalimide fluorophore, which undergoes internal charge transfer in the excited state, is crucial for the suitability of the compound as a pH sensor. In studies of the pH dependence of the fluorescence of the regioisomers 1 and 2, only 1 displayed desirable properties.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Anion Recognition and Sensing: The State of the Art and Future Perspectives

Abstract: Anion recognition chemistry has grown from its beginnings in the late 1960s with positively charged ammonium cryptand receptors for halide binding to, at the end of the millennium, a plethora of charged and neutral, cyclic and acyclic, inorganic and organic supramolecular host systems for the selective complexation, detection, and separation of anionic guest species. Solvation effects and pH values have been shown to play crucial roles in the overall anion recognition process. More recent developments include exciting advances in anion-templated syntheses and directed self-assembly, ion-pair recognition, and the function of anions in supramolecular catalysis.