Project 5

Silicon Microreactor for Analysis of Trace VOCs in Exhaled Breath

(Prof. X. Fu, ChE)

Microreactor with two fused silica tubes attached. Insert: SEM micrograph of the micropillar array.

In this project an REU student will learn how to fabricate a microreactor and use it for analysis of trace volatile organic compounds (VOCs) in exhaled breath. Microreactors are transformative devices for next-generation healthcare analysis of trace volatile organic compounds (VOCs) in human exhaled breath [1-4]. Some VOCs in breath are disease metabolites or biomarkers diffused from blood to exhaled breath through the lung. The Fu Research Group fabricates a new generation of microreactors on silicon wafers using MEMS techniques including photolithography and deep reactive ion etching (DRIE) to create thousands of micropillars in the microreactors. The surfaces of the micropillars are then coated with reactants such as aminooxy compounds for capture of carbonyl VOCs via reactions. After being sealed with a glass wafer, the wafer is diced to obtain 24 microreactors. The VOCs adducts captured by the microreactor are eluted by solvents, and then the eluted solutions are analyzed by UHPLC-MS and GC-MS. The figure above shows an image of a microreactor and the micropillar array inside the microreactor channel. The REU student will participate in the microfabrication, CFD (computational fluid dynamics) simulation of fluid flow in the microreactors, capture of VOCs by the microreactors, and quantitative analysis of trace VOCs. An undergraduate student interested in Chem, ChE, ME or BE is an ideal REU applicant.

References

[1] M.X.Li, D. Yang, G. Brock, R.J. Knipp, M. Bousamra, M.H. Nantz, X.A. Fu, “Breath carbonyl compounds as biomarkers of lung cancer”, Lung Cancer 2015, 90, 92-97.

[2] X. A. Fu, M. Li, R. J. Knipp, M. H. Nantz, M. Bousamra, “Noninvasive detection of lung cancer using exhaled breath”, Cancer Medicine 2014, 3, 174-181.

[3] M. Li, S. Biswas, M.H. Nantz, R.M. Higashi, X.A. Fu, “A microfabricated preconcentration device for breath analysis” Sensors & Actuators B 2013,180, 130–136.

[4] M. Li, S. Biswas, M.H. Nantz, R.M. Higashi, X.A. Fu, “Preconcentration and analysis of trace volatile carbonyl compounds”, Analytical Chemistry 2012, 84, pp.1288-1293, DOI: 10.1021/ac2021757.