Photoelectric chemical and biological sensors

We have developed a new and widely-applicable chemical sensing technology based on the coordinated detection of photo-induced charge movements (PICM) of reporter molecules embedded in polymer films. This general technique has been successfully applied to the detection of biomolecules such as sugars as well as other biochemicals. By detecting specific pathogen derived biomolecules, a pathogen-specific sensor can be constructed. We have shown the feasibility of this approach by fabricating a sensor sensitive to the presence of molecules of bacterial origin. These sensors can have a real-time response. They are also inexpensive to manufacture and can be made disposable. We are developing a miniature array of such sensors that may be able to concurrently determine a variety of analytes. Besides biomolecules, this sensing technology can also be applied to the quantification of other organic and inorganic chemicals such as oxygen and ions. The ability of oxygen as well as other molecules to interact with singlet states of molecules and quench fluorescence can also affect the mechanisms that product PICM. For some molecules the quenching of PICM can be shown to follow typical Stern-Volmer quenching. We have investigated the oxygen-sensitivity of several families of compounds known to produce PICM, including the fullerenes.