Five-Dimensional Hadamard-Transform Fluorescence Imaging
| dc.contributor.author | Katz, Oren G. | |
| dc.contributor.supervisor | Loock, Hans-Peter | |
| dc.date.accessioned | 2022-12-16T23:45:02Z | |
| dc.date.copyright | 2022 | en_US |
| dc.date.issued | 2022-12-16 | |
| dc.degree.department | Department of Chemistry | |
| dc.degree.level | Master of Science M.Sc. | en_US |
| dc.description.abstract | A home-built imaging system is designed and characterized which can capture fluorescence over two spectral dimensions (excitation and emission wavelengths) and two spatial dimensions (x and y), at an acquisition rate fast enough to study dynamic chemical systems which change over time (t) and exhibit both complex spectra and spatial inhomogeneity. Fluorescence excitation-emission matrix (EEM) spectroscopy can identify compounds based on their unique fluorescence fingerprint, but the acquisition rates of conventional techniques are too slow and restrict applications of EEM spectroscopy to static solutions. Furthermore, none of the EEM systems reported to date provides spatial information on how fluorescence EEM signatures may differ in an inhomogeneous sample. The imaging system described in this thesis uses a fully programmable light source to illuminate a sample with many wavelengths simultaneously, instead of one at a time. Our approach is based on Hadamard-transform (HT) multiplexing and can decrease the acquisition time 500-fold compared to conventional methods. By coupling the programmable light source to an eight-channel snapshot hyperspectral camera, the emission and excitation response can be measured for each of the 256×256 pixels in an image – producing 65,536 EEM spectra in less than 8 seconds. A tensor-rank decomposition method, parallel factor analysis (PARAFAC), is employed to distill the five-dimensional (x, y, λex, λem, t) dataset to the component fluorophores, whose kinetics and chemical transformations can then be studied independently of one another. The HT-EEM imaging system is demonstrated with two fluorescent dyes (rhodamine B and fluorescein) in a mixture with different solvent phases. The fluorescence EEM of each dye is identified both spatially and spectrally. One hundred 4D images are acquired over 13 minutes while the mixture is heated, to study the thermal quenching effects on Rhodamine B. The applicability of this technology towards high-throughput assays and information-rich fluorescence microscopy is briefly discussed. | en_US |
| dc.description.scholarlevel | Graduate | en_US |
| dc.identifier.bibliographicCitation | O. G. Katz and H. Loock, "Multi-Dimensional Hadamard-Transform Fluorescence Imaging," in Applied Industrial Optics (AIO) 2022, A. Smith and G. Miller, eds., Technical Digest Series (Optica Publishing Group, 2022), paper T1A.2. | en_US |
| dc.identifier.uri | http://hdl.handle.net/1828/14562 | |
| dc.language | English | eng |
| dc.language.iso | en | en_US |
| dc.rights | Available to the World Wide Web | en_US |
| dc.subject | Imaging | en_US |
| dc.subject | Instrument Design | en_US |
| dc.subject | Fluorescence | en_US |
| dc.subject | Multiplexing | en_US |
| dc.subject | Hadamard-Transform | en_US |
| dc.subject | EEM | en_US |
| dc.subject | Spectroscopy | en_US |
| dc.title | Five-Dimensional Hadamard-Transform Fluorescence Imaging | en_US |
| dc.type | Thesis | en_US |