One key problem in making low absorbance measurements is the random noise generated in various system components such as photodetectors, etc. Another class of problems is environmental in origin, such as airborne or sample-borne contamination, and schlieren effects. The proposed instrument, based on well known wavelength modulation techniques, but novel in certain critical aspects, substantially reduces the impact of these error sources. It is estimated that it will accurately measure kinetic absorbance changes as low as one microabsorbance unit per second within 100 seconds. This represents several orders of magnitude improvement over current instruments. During Phase 1, the key conceptual features of the instrument will be tested, both by further mathematical modeling and also experimentally. A breadboard instrument using commercially available components will be subjected to accuracy, sensitivity, and stability tests.Anticipated Results and
Potential Commercial Applications: This instrument will find immediate use by allowing non-radioactive formulation of assays for rapid diagnosis of communicable diseases such as salmonella, malaria, tuberculosis, etc. Other applications may include environmental and atmospheric sciences.
