[Vitamin C: antioxidant barrier]. / Witamina C--bariera antyoksydacyjna.

There is growing interest concerning the role of vitamin C in physiological conditions. In this paper L-ascorbic acid is discussed in detail including its chemical activity and biological properties. The primary goal of this review is to present the chemical characteristics of this substance and to discuss its relation to various biological functions of vitamin C, mainly as an antioxidant barrier.

Application of ammonium peroxidisulfate and metavanadate for spectrophotometric determination of prothipendyl hydrochloride.

Prothipendyl hydrochloride reacts with (NH4)2S2O8 and NH4VO3 forming the coloured oxidation products which exhibit maximum absorbance at lambda = 372 nm and 374 nm, respectively. The optimum conditions of the reaction have been established. It was found that Beer's law is obeyed in the concentration range 3-95 microg/ml and 3-90 microg/ml in PTP-(NH4)2S2O8 and PTP-NH4VO3 system, respectively.

Application of reinecke salt and alizarin S for the determination of promazine.

Reinecke salt and alizarin S have been tested as reagents for the determination of promazine. They react in neutral and acidic media with promazine forming a reddish and brown crystalline compounds. The compounds are sparingly soluble in water but fairly soluble in acetone and methanol. The quantitative extraction of compound of promazine with alizarin S has been used for the extractive spectrophotometric determination of promazine. Formation of promazine ion-association complex with Reinecke salt has been applied for indirect determination of low concentrations of promazine by AAS measurement of the chromium content of the reineckate counter - anion.

FIA of vitamin C in blood serum in humans at increasing ethanol concentration.

The evaluation of the ethanol influence on the changes in vitamin C levels has been done in humans at increasing ethanol concentration. Flow injection analysis method (FIA) with the spectrophotometric detection was used to determine L-ascorbic acid levels. The procedure is based on the oxidation of the analysis with iron (III) and 2,2'-dipyrydyl. Concentrations of vitamin C in the range of 0.4-1.3 ppm have been determined with a relative standard deviation (R.S.D.) 1.2% (n=15). The injection rate was 40 samples h(-1). The comparison of L-ascorbic acid levels in humans showed a statistical difference at P<0.05 in the analysed group.

[Biological role of reactions of L-ascorbic acid with metals]. / Biologiczna rola reakcji kwasu L-askorbinowego z metalami.

L-ascorbic acid (H2Asc) is one of the basic vitamins, necessary to the normal growth and behaviour of organisms. The primary goal of this review is to present the chemical characteristics of this substance and to discussed its relation to various biological functions of vitamin C, mainly as a free radical scavenger. In presented work author analysed of same metals Cu(II), Zn(II), Cd(II), Hg(II), Pb(II) with L-ascorbic acid, showing preventive activity of vitamin C at exposure on metals.

[The role of vitamin C in absorption and dismissing of ions of metals]. / Rola witaminy C we wchlanianiu i wydalaniu jonów metali.

There is growing interest in the physiological role of vitamin C. In this paper L-ascorbic acid is discussed in detail, including its chemical properties and biological activity. The primary goal of this review is to present the chemical characteristic of this compound and to discuss its relation to various biological functions of vitamin C in absorption and to dismissing of ions of metals.

Determination of chelate complexes by spectrophotometry; L-ascorbic acid with cadmium (II) and zinc (II) in alkaline solution.

The chemical behaviour of L-ascorbic acid (H2Asc) with cadmium (II) and zinc (II) in alkaline medium was studied. The total stability constants of the examined complexes and their composition were determined by spectrophotometry (Jacymirsky and computer) method. An attempt has been made to explain the nature of complexes formed in the systems Cd (II)-H2Asc-H2O and Zn (II)-H2Asc-H2O and the interaction between these compounds.

[Contemporary opinions on the role and properties of L-ascorbic acid]. / Wspólczesne poglady na funkcje i wlasciwosci kwasu L-askorbinowego.

There is growing interest in the role of vitamin C physiological role. In this paper L-ascorbic acid is discussed in detail, including its physical properties, chemical activity and biological properties. The primary goal of this review is to present the chemical characteristics of this compound and to discuss its relation to various biological functions of vitamin C, mainly as a free radical scavenger.