David Johnston

Title: David Johnston: Innovator in Halohydrocarbon Detection

Introduction

David Johnston is a notable inventor based in San Jose, CA. He has made significant contributions to the field of analytical chemistry, particularly in the detection of halohydrocarbons in water. With a total of 4 patents to his name, Johnston's work has advanced the methods used for environmental monitoring.

Latest Patents

One of Johnston's latest patents is a real-time, on-line method and analytical system for determining halohydrocarbons in water. This innovative system operates by extracting on-line samples and purging volatile halohydrocarbons from the water using air or nitrogen. The purge gas containing the analytes of interest is then carried over a porous surface where the analytes are adsorbed. The recovery of these analytes from the porous surface can be achieved through thermal desorption or solvent elution, driving them into an organic chemical mixture. The system generates an optical change, such as a color change, based on a reaction involving the analytes and a pyridine derivative. Finally, it measures the optical characteristics associated with the reaction to quantify the concentration of volatile halogenated hydrocarbons.

Career Highlights

Throughout his career, David Johnston has worked with various companies, including Ams Trace Metals, Inc. His expertise in analytical methods has positioned him as a key figure in the development of technologies for environmental analysis.

Collaborations

Johnston has collaborated with notable individuals in his field, including Harmesh K. Saini and Michael J. West. These collaborations have contributed to the advancement of his innovative work.

Conclusion

David Johnston's contributions to the detection of halohydrocarbons demonstrate his commitment to innovation in analytical chemistry. His patents reflect a deep understanding of environmental monitoring techniques, making him a valuable inventor in this field.