Sensitized chemiluminescence in micellar mixtures of phthalhydrazide and selected dyes

Hrbáč, Jan; Sichertova, D; Bancı́řová, Martina; Lasovský, Jan; Papadopoulos, Kyriakos; Nikokavouras, J.

doi:10.1016/j.jphotochem.2004.04.019

Cited by 4 publications

(1 citation statement)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They are suggested as having vaso relaxant [1], antihypertensive [2], or anti-HIV activities [3]. These compounds are referenced in chemiluminescence studies [4] and they are also used to prepare membranes for several purposes [5,6]. Although their high importance and large applications, the thermochemical data available in the literature for nitrogen heterocycles are still scarce, besides the fact that some of the available data do not have the necessary accuracy.…”

Section: Introductionmentioning

confidence: 99%

Experimental study on the thermochemistry of 1-(2H)-phthalazinone and phthalhydrazide

Silva

Cabral

2008

The Journal of Chemical Thermodynamics

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Experimental study on the thermochemistry of 1-(2H)-phthalazinone and phthalhydrazide

Silva

Cabral

2008

The Journal of Chemical Thermodynamics

View full text Add to dashboard Cite

The photodynamic effect: the comparison of chemiexcitation by luminol and phthalhydrazide

Bancı́řová

Lasovský

2010

Luminescence

Self Cite

View full text Add to dashboard Cite

The presence of light, oxygen and photosensitizer (organic dye) is required for the photodynamic effect. Light and photosensitizer are harmless by themselves, but when combined with oxygen, reactive oxygen species (ROS) can be produced. This photodynamic effect is used in photodynamic therapy (PDT); the production of ROS as lethal cytotoxic agents can inactivate tumor cells. However, during PDT, there are many difficulties, so it is not possible to excite the photosensitizer using a laser, a source of light at the wavelengths specific to the photosensitizer (in visible region of the spectrum). Chemiluminescence is the light emission as a result of a chemical reaction. It is possible to use a chemiluminescent mixture to excite the photosensitizer even if the light emission does not conform to the absorption maximum of the photosensitizer. Luciferin and luminol have been used as chemiluminescent compounds (energizers) for the excitation of the photosensitizers. The aim of this work was to compare the chemiexcitation of some selected photosensitizers (e.g. fluorescein, eosin, methylene blue, hypericin and phthalocyanines) by chemiluminescent mixtures containing luminol (high chemiluminescent quantum yield) or phthalhydrazide (low chemiluminescent quantum yield) on some Gram-positive (Enterococcus faecalis, Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa, E. coli) bacteria and some cell lines (NIH3T3 and MCF7). The efficiency of the chemiexcitation was dependent on the kind of the photosensitizer and on the type of the bacterial strain or cell line and was independent of the energizers.

show abstract

Oxidation and chemiluminescence of catechol by hydrogen peroxide in the presence of Co(II) ions and CTAB micelles

Lasovský¹,

Hrbáč²,

Sichertova³

et al. 2007

Luminescence

View full text Add to dashboard Cite

The oxidation of catechol in neutral and slightly alkaline aqueous solutions (pH 7-9.6) by excess hydrogen peroxide (0.002-0.09 mol/L) in the presence of Co(II) (2.10(-7)-2.10(-5) mol/L) is accompanied by abrupt formation of red purple colouration, which is subsequently decolourized within 1 h. The electron spectra of the reaction mixture are characterized by a broad band covering the whole visible range (400-700 nm), with maximum at 485 nm. The reaction is initiated by catechol oxidation to its semiquinone radical and further to 1,2-benzoquinone. By nucleophilic addition of hydrogen peroxide into the p-position of benzoquinone C=O groups, hydroperoxide intermediates are formed, which decompose to hydroxylated 1,4-benzoquinones. It was confirmed by MS spectroscopy that monohydroxy-, dihydroxy- and tetrahydroxy-1,4-benzoquinone are formed as intermediate products. As final products of catechol decomposition, muconic acid, its hydroxy- and dihydroxy-derivatives and crotonic acid were identified. In the micellar environment of hexadecyltrimethylammonium bromide the decomposition rate of catechol is three times faster, due to micellar catalysis, and is accompanied by chemiluminescence (CL) emission, with maxima at 500 and 640 nm and a quantum yield of 1 x 10(-4). The CL of catechol can be further sensitized by a factor of 8 (maximum) with the aid of intramicellar energy transfer to fluorescein.

show abstract

Sensitized chemiluminescence in micellar mixtures of phthalhydrazide and selected dyes

Cited by 4 publications

References 21 publications

Experimental study on the thermochemistry of 1-(2H)-phthalazinone and phthalhydrazide

Experimental study on the thermochemistry of 1-(2H)-phthalazinone and phthalhydrazide

The photodynamic effect: the comparison of chemiexcitation by luminol and phthalhydrazide

Oxidation and chemiluminescence of catechol by hydrogen peroxide in the presence of Co(II) ions and CTAB micelles

Contact Info

Product

Resources

About