DNA oligomers can stabilize few-atom Ag clusters in aqueous solution. Some of the resulting AgDNAs are fluorescent with chemical stabilities, excitation and emission wavelengths, and quantum yields that depend strongly on the DNA sequence. 6 This sequence dependence has been exploited for detecting disease-related DNA mutations and for identifying promising biolabels. Rational design of AgDNA f...

The effects of the nonlinear behavior of fluorescent intensity with excitation intensity on emission reabsorption laser-induced fluorescence (ERLIF) are investigated. Excitation nonlinearities arise mainly as a consequence of the depletion of the ground-state population stemming from the finite lifetime of molecules in the excited state. These nonlinearities hinder proper suppression of the exc...

Fluorescence spectroscopy was examined as a potential technique for identification and classification of bacterial pathogens. Colonies of Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, and Klebsiella pneumoniae on agar plates were measured directly using a laboratory spectrofluorimeter coupled with optical fiber. Steady state fluorescence spectra were collected following excit...

We report on the discovery, isolation, and use of a novel yellow fluorescent protein. Lucigen Yellow (LucY) binds one FAD molecule within its core, thus shielding it from water and maintaining its structure so that fluorescence is 10-fold higher than freely soluble FAD. LucY displays excitation and emission spectra characteristic of FAD, with 3 excitation peaks at 276 nm, 377 nm, and 460 nm and...

III POPULÄRVETSKAPLIG SAMMANFATTNING V ACKNOWLEDGEMENTS VI LIST OF PUBLICATIONS XI CHAPTER 1: PREAMBLE AND A PRIOR ART 1 UBIQUITOUS SENSING: AN INTRODUCTION 3 CSPT: PRIOR ART 6 CSPT: THE NEXT PHASE 7 CHAPTER 2: EXPOUNDING THEORY 9 PEEM: FINGERPRINTS 11 PEEM: THE POLYCHROMATIC EXCITATION EMISSION MATRIX 15 FLUORESCENCE AND PRIOR ART 19 SU-8 MICROSTRUCTURES 21 PAPER 1: 2D MODELLING 22 PAPER 1: 3D...

The performances of support vector machine (SVM) and linear discrimination analysis (LDA) for detecting pesticide on spinach leaf were investigated. Fluorescence images of spinach leaves without any treatment, treated with pure water and methamidophos solution were taken under 561 different wavelength conditions to acquire hyperspectral excitation-emission matrix (EEM) data. Then LDA and SVM we...

Wavelength-selective fluorescence comprises a set of approaches based on the red edge effect in fluorescence spectroscopy, which can be used to monitor directly the environment and dynamics around a fluorophore in a complex biological system. A shift in the wavelength of maximum fluorescence emission toward higher wavelengths, caused by a shift in the excitation wavelength toward the red edge o...