Laser-induced fluorescence spectroscopy and collection into liquid solution of aerosol particles

Improvements have been made to the laser-induced fluorescence particle spectrometer so that spectra from two excitation lasers at separate wavelengths can be recorded for each particle analyzed. This allows for additional discrimination ability over using a single excitation wavelength. The use of a heated inlet tube is also investigated, and some of the effects of heating on aerosols and how the aerosol population is changed by heating are described. A large amount of ambient aerosol data from outdoors air in New Haven, CT was collected, and the resulting data set is analyzed using cluster analysis. Various clustering algorithms are examined. Cluster analysis also provides insights to the additional discrimination ability of using two excitation wavelengths, and provides templates for analysis of the heated inlet tube data. Both aerodynamic deflection using an air puffer and electrostatic deflection using an electrospray are tested in order to deflect aerosols into a liquid solution within the input well of a microfluidic device. Proof-of-concept experiments demonstrating deflection of E. coli using the puffer into a microfluidic diagnostic using fluorescein-labeled antibodies targetting E. coli, and deflection of rhodamine B dye droplets using electrospray were performed.