A plasticized Cr3+ ion sensor by incorporating 2,3,8,9-tetraphenyl-1,4,7,10-tetraazacyclododeca-1,3,7,9-tetraene (TTCT) ionophore exhibits a good potentiometric response for Cr3+ over a wide concentration range (1.0 x 10(-6)-1.0 x 10(-1) M) with a slope of 19.5 mV per decade. The sensor response is stable for at least three months. Good selectivity for Cr3+ in comparison with alkali, alkaline e...

The acid-base equilibrium of lorazepam was studied by means of potentiometry andmultiwavelengths spectrophotometry. The stoichiometric equilibrium constants were determinedat 25 °C and constant ionic strength 0.1 mol L-1 (NaCl). The acidity constants pK1=1.58±0.05and pK2=11.67±0.07 were found by potentiometry, and pK1=1.54±0.02 and pK2=11.61±0.03 bymulti-wavelengths spectrophotometry. Potentiom...

In this study, a potentiometric sensor composed of palm shell activated carbon modified with trioctylmethylammonium thiosalicylate (TOMATS) was used for the potentiometric determination of mercury ions in water samples. The proposed potentiometric sensor has good operating characteristics towards Hg (II), including a relatively high selectivity; a Nernstian response to Hg (II) ions in a concent...

Potentiometric sensor based on commercial pencil graphite electrodes coated with polyaniline (PAni) composite with Eosin Y (EY) termed as PGE/PAni-EY have been developed for potentiometric determination of silver ion. The electrode exhibited linear response with Nernstian slope of 57.6±0.8 mV per decade within the range of 1.0×10 to 1.0×10 M with limit of detection 6.5×10 M silver ion. Fast and...

An automatic system for the potentiometric determination of boron in ceramic frits was developed. The system includes a personal computer for instrumental control, data acquisition and processing, which allows up to 13 samples to be analysed sequentially with no human intervention.The system performance was tested on the titration of standard solutions, which it carried out with low errors and ...

Captopril, chemically know as 1-[(2S)-3mercapto-2-methylpropionyl]-L-proline, (CPT) is used therapeutically as an antihypertensive agent [11, 15], which is also prescribed for the treatment of congestive hart failure [6]. Several types of analytical procedures have been proposed for the analysis of captopril in pharmaceuticals formulations. These procedures include capillary electrophoresis [13...

Stress was firstly defined in 19351, as a reaction of humans to external stimuli. In the modern way of life and every day actions, the term stress is very common and has a significant influence on human reactions, health, work ability and mood. There is also a direct connection between stress and depression in humans2. Apart from adults, recent studies show that preschool children are also unde...

Coenzyme A (CoA or CoASH) is one of the most important biologically active compounds, and for this reason a reliable, fast and simple determination of CoASH is needed. Here we are described a simple and fast way of determinating CoASH using potentiometric flow-injection analysis and spectrophotometric kinetic determination. The described methods are suitable for use over a wide concentration ra...

A poly (vinyl chloride) membrane electrode with dibutyl phthalate as plasticizer based on the fentanyl-phosphotungstate ion-association complex as ion-exchange site for the determination of fentanyl citrate in injections was developed. A linear response for 1 x 10(-5)-1 x 10(-2) mol dm(-3) drug with a slope of 55.9 +/- 0.4 mV per decade was established. The optimum pH range was 1-7. The lower d...