Published in Journal of Fluorescence
A significant challenge concerning the development of fluorescence lifetime (FL) based pH sensors is the paucity of fluorophores with sufficiently large FL variation with pH. Acridine is amongst the indicators with highest fluoresce lifetime responses to pH, with a change in lifetime of about 13 ns within a pH range of 5–8. Here we examine the two ...
Published in Journal of Fluorescence
Zn(II)-octa-(4-chlorophenyl)- and Zn(II)-octa-(4-bromophenyl)tetraazaporphyrins were synthesized by the reaction of cyclotetramerization of di-(4-chlorophenyl)- and di-(4-bromophenyl)maleonitriles with zinc(II) chloride. The obtained compounds were identified by UV-vis, IR, NMR 1H spectroscopy and mass spectrometry. Geometry optimization of the ser...
Published in Journal of Fluorescence
Hot-band absorption and anti-Stokes emission properties of an organic fluorescent dye, Alexa Fluor 568, were characterized and compared with those of Rhodamine 101. The comparison of the properties (e.g., quantum efficiency, spectral distribution, thermal properties, and fluorescence lifetime) between the two dyes confirms that both dyes undergo th...
Published in Journal of Fluorescence
The new derivative of coumarin ( E )-3-[7-(diethyloamino)-2-oxo-chromen-3yl]-2-(tiophene-2-carbonyl)prop-2-enenitrile (NOSQ) was easy synthesized with commercial substrates as a result of the search of new Michael type addition sensors based on coumarins. Spectral properties of highly emissive NOSQ were investigated by steady state analysis (absorp...
Published in Journal of Fluorescence
A facile synthesis procedure, whereby 9-Anthraldehyde (AA) is coupled to aminated rhodamine (AR) via a Schiff base-type reaction, is reported. The applicability and performance of the obtained material (AA-AR) as a sensing agent was studied towards 16 metal cations (i.e. Li+, Na+, Ag+, Ca2+, Ba2+, Co2+, Cs+, Cu2+, Mg2+, Hg2+, Mn2+, Pb2+, Ni2+, Sr2+...
Published in Journal of Fluorescence
Autofluorescence of the bone extracellular matrix (ECM) has not been widely explored although the ECM plays a very important role in bone development. In our research we focused on examining the bone matrix of very young animals due to the intense growth process during the first month of life. Structure images and fluorescence spectra of the bone s...
Published in Journal of Fluorescence
In this work, we report a new chemiluminescence system using bis-(2,4,6-trichlorophenyl) oxalate (TCPO) with hydrogen peroxide and luminol as fluorophore. The intense chemiluminescence reaction here described was fully investigated and it was determined that this fluorescent system has two strong light emissions at 440 and 490 nm, respectively. Thi...
Published in Journal of Fluorescence
Several studies have been carried out on flashing of fireflies till now. From patterns of its flashes in different ambient conditions, different conclusions have been drawn and hypotheses put forward. Here we observe flashes emitted by two Indian species of firefly Luciola praeusta and Asymmetricata circumdata. For the species L. praeusta, as the t...
Published in Journal of Fluorescence
Perimidines are a particularly versatile family of heterocyclic compounds, whose properties are exploited in several applications ranging from industrial to medicinal chemistry. The molecular structure of perimidine incorporates a well-known efficient fluorophore, i.e.: 1,8-diaminonaphthalene. The high fluorescence quantum yield shared by most naph...
Published in Journal of Fluorescence
The spectroscopic and laser characteristics of two benzopyrane derivatives for 600–670 nm spectrum region of lasing in preliminarily annealed silica xerogel matrices in non-selective cavity under laser pumping at 551 nm have been measured and analysed. The influence of molecular structure of the dyes on their non-radiating losses has been revealed....
