Degree Granting Department
Luis Humbolt Garcia-Rubio , Ph.D.
Myung Keun Kim, Ph.D.
Nicholas Djeu, Ph.D.
Pritish Mukherjee, Ph.D.
Maria Kallergi, Ph.D.
Light scattering, Transmission, Fluorescence, Joint particle property distributions, Particle shape and composition
Characterization of micron and sub-micron size particles requires the simultaneous measurement of the joint particle property distribution (JPPD). The JPPD is comprised of particle size, shape, orientation, composition, optical properties, and surface properties. Measurement of each of the particle properties independently is a difficult task and it has been only partially successful. To determine as many particle properties as possible using optical methods it is necessary to simultaneously measure all aspects of the interaction of the incident light with the particles of interest. This approach leads to the concept of multidimensional spectroscopy suggested by Prof. Garcia-Rubio. Dr. Bacon proved the proposition by developing and testing a prototype multianglemultiwavelength (MAMW) spectrometer proposed by Prof. Garcia-Rubio. However, the prototype MAMW spectrometer has limitations in the amount of information it can obtain because of strong absorption of deep UV light and detector saturation due to the use of optical fibers and single integration time for the CCD detector.
The Integrated UV-VIS MAMW spectrometer has been developed to overcome the limitations of the prototype MAMW spectrometer. Improvements have become possible through the use of UV lenses and integration time multiplexing (ITM). The Integrated UV-VIS MAMW spectrometer has the capabilities to perform low angle scattering measurements starting from 4o with simultaneous detection of multiwavelength light from 200 nm to 820 nm, UV-VIS transmission spectroscopy, and frequency domain fluorescence spectroscopy. Following the development, possible sources of errors were analyzed and data calibration procedures have been established to ensure the validity and reproducibility of the measurement results.
The capabilities of the Integrated UV-VIS MAMW spectrometer were tested by measuring UV-VIS MAMW spectra of polystyrene standards. The measured UV-VIS MAMW spectra clearly show differences due to particle size, shape, and compositional changes. Measurements of the UV-VIS MAMW spectra of sickled whole blood samples demonstrate that particle shape and compositional changes can be detected simultaneously. These results confirmed that the Integrated UV-VIS MAMW spectrometer could be a powerful tool for the characterization of micron and sub-micron size particles. Alternate approaches to enhance these capabilities further, i.e., the development of a new multidimensional MAMW spectrometer, are also described.
Scholar Commons Citation
Kim, Yong-Rae, "Integrated Uv-Vis Multiangle-Multiwavelength Spectrometer For Characterization Of Micron And Sub-Micron Size Particles" (2004). Graduate Theses and Dissertations.