We report the synthesis and optical properties of organic porphyrin nanoparticles with narrow size distribution and good dispersibility. Nanoparticles were produced by a combination of precipitation and sonication, termed the "ultrasonic method". The resulting [tetrakis(para-chlorophenyl)porphyrin]TClPP nanoparticles were stable in solution without precipitation for at least 30 days. No self ag...

A Bodipy based, highly selective probe for hydrogen sulfide has been designed, synthesized and demonstrated to detect H2S in living cells. In this design, the reduction of two arylazido groups change the charge transfer characteristics of the 3,5-distyryl substituents on the Bodipy core, producing a 20 nm bathochromic spectral shift in the absorption band, and quenching of the emission by 85% c...

A new chromogenic protocol has been developed for rapid and selective detection of nerve agents like tabun. The chemsensor displayed a drastic color change from its colorless solution to yellow instantaneously with an 89 nm bathochromic shift. No inference of other chemical warfare agents and its mimics was observed either with the naked-eye or by UV-Vis spectroscopy. The development of a porta...

Rutacridone, 1-hydroxy-A-methylacridone, and l-hydroxy-3-methoxy-A-methylacridone have been isolated for the first time from callus cultures, which had been obtained from meristematic stem cells of Ruta graveolens L. The alkaloids were identified by co-chromatography with authentic compounds, by IR spectra, and by electronic spectra before and after addition of A1C13 . The use of the bathochrom...

Sodium acetate (NaOAc) can selectively ionize 7-OH of naringenin generating a bathochromic shift of 41nm in its UV absorbance. This principle is used in the described spectrophotometric method that can detect naringenin amidst naringin and prunin present in the incubation mixture of naringinase. The method could be adopted for real sample analysis as it remains unaffected by the presence of phe...

Z. Naturforsch. 51 b, 377-380 (1996); received October 4, 1995 Spectroelectrochemistry, MO-Calculations, Xanthenoxanthenes, Radical Cation, Dication Spectroelectrochemistry of 2,5,8,1 l-tetra-rm-butyl-p^n'-xanthenoxanthene 1 yields the UV/VIS spectra of the corresponding radical cation l '+ and dication 12+. The bathochromic shift for the dication 12+ relative to 1 and to the isoelectronic hydr...

An ion pair reversed phase HPLC method for the determination of clavulanic acid has been developed. Since clavulanic acid had poor absorption O,mas 201 nm in water) in a UVregion suitable for HPLC detection, the detectability was enhanced by bathochromic shift of )maa due to solvent effect. The shifts of 2ma.., were measured with the solutions containing clavulanic acid, tetrabutylammonium brom...

Boron subphthalocyanines (SPcs) are aromatic macrocycles that possess a combination of physical and optical properties that make them excellent candidates for application as fluorescent imaging probes. These molecules have intense electronic absorption and emission, and structural versatility that allows for specific tuning of physical properties. Herein, we report the synthesis of a series of ...