8-Hydroxyquinoline-7-sulfonic acid

Zn+8-hydroxyquinoline-5-sulfonate — Zn(8-hydroxyquinoline-5-sulfonate)+2e , Zn(N03)2, 8-hydroxyquinoline-5-sulfonic acid -1.021 54Nas... 

Iron Preconcentration on 8-hydroxyquinoline-5-sulfonic acid column, luminol-H202 CL 2 pg/mL 50... 

Bishop JA (1963) Complex formation and fluorescence complexes of 8-hydroxyquinoline-5-sulfonic acid. Anal Chim Acta 29 172-177... 

Soroka K, Vithanage RS, Phillips DA et al (1987) Fluorescence properties of metal complexes of 8-hydroxyquinoline-5-sulfonic acid and chromatographic applications. Anal Chem 59 629-636... 

These equations show the general theoretical basis for the empirical order of rate constants given earlier for electrophilic attack on an aromatic ligand L, its metal complex ML, and its protonated form HL, one finds kt > n > hl. Conflicting reports in the literature state that coordination can both accelerate electrophilic aromatic substitution (30) and slow it down enormously (2). In the first case the rates of nitration of the diprotonated form of 0-phenanthroline and its Co(III) and Fe(III) complexes were compared. Here coordination prevents protonation in the mixed acid medium used for nitration and kML > h2l. In the second case the phenolate form of 8-hydroxyquinoline-5-sulfonic acid and its metal chelates were compared. The complexes underwent iodination much more slowly, if at all, and kL > kML ... 

Mg(II) forms a complex with 8-hydroxyquinoline-5-sulfonic acid (37) at pH 9.0 with Tris-HCl buffer, which can be determined by ELD (X x = 388 nm, ka = 495 nm) with micellar enhancement by cetyltrimethylammonium chloride (38). Masking of Ca(II) is achieved by EGTA (19). The method was applied in a SIA system for analysis of natural waters . After elution of the Mg(II) ions adsorbed on an alkali-activated PTFE tube with 0.1 M HCl and addition of A,A -bis(salicylidene)-2,3-diaminobenzofuran (39), the end analysis was by fluorometric determination of the Mg(II) complex (kex =475 nm, kfl = 545 nm). Possible interference of Ca(II) is masked on addition of the chelating agent... 

In addition to these kinetic studies, there has been a considerable amount of work on the thermodynamic parameters associated with this type of reaction. Thus the interaction of [M(edta)aq] with anions of 8-hydroxyquinoline-5-sulfonic acid (oxs ), ida2- and nitrilotriace-tic acid (nta3-) was thoroughly studied for M = Y, La-Lu (except Pm) by calorimetry and pH titration,419 and AG, AH, AS and K found. Some of these values are given in Table 5. It was, however, concluded from the variation of these parameters with atomic number that all M3+ in aqueous solution have the same coordination number (nine) but that the coordination number of the [M(edta)aq] species changes between Sm3+ and Tb. ... 

Simpson and Vallee (51) found that when alkaline phosphatase is exposed to 8-hydroxyquinoline-5-sulfonic acid, two zincs are rapidly removed and the enzyme is inactivated to within 10%. The two remaining zincs are removed more slowly, presumably with the loss of the remaining activity. 

Applebury and Coleman 48) found that biosynthetic enzyme and apoenzyme labeled with 85Zn bound 2-3 zinc ions per dimer at neutral pH but as many as 7 at pH 10.0. Dialysis for 24 hr removes extra zinc, and after 20 days only two remain and the enzyme is active. Thus it appears that the two zinc binding sites that are most readily occupied in the apoenzyme and must be occupied for activity are the ones that most strongly retain zinc ions during dialysis but, on the other hand, most readily lose zinc ions by reaction with 8-hydroxyquinoline-5-sulfonic acid. 

Disodium hydrogen phosphate Sodium acetate solution Cupferron (CeH5N(NO)ONH4) aqueous solution, freshly prepared Ammonium thiocyanate + dilute acid 7-lodo-8-hydroxyquinoline-5-sulfonic acid (ferron)... 

The ternary complex formed by the reaction of lanthanide ions (La(III) and Y(III)) with 7-(l-naphthylamineazo)-8-hydroxyquinoline-5-sulfonic acid has been exploited for the fluorimetric determination of EDTA over the range of 2-20 pM. The fluorescence is measured at 525/350 nm [37], A similar method based on the reaction of Ca(II) with Fluo-3 and EDTA... 

Fluorimetric methods [34] Fluorimetric sequential injection analysis of magnesium in commercial drinking waters is based on the complexation of magnesium (II) with 8-hydroxyquinoline-5-sulfonic acid in the presence of ethylene glycol-bis(6-aminoethyl ether)-N,N,N, N -tetra-acetic acid as a masking agent and cetyltrimethylammonium chloride as the fluorescence enhancer. 

Curves which are of the same form as curve B have been obtained for the diazo-coupling (52) and iodination (, 7,13) of 8-hydroxyquinoline-5-sulfonic acid and its metal complexes and for the oxidation of glucose and its boric acid complex with ferricyanide (50). 

Among the derivative of HQ, 8-hydroxyquinoline-5-sulfonic acid (HQS) is attractive because of the enhanced water-solubility of the metal complexes it forms (Fig. 7.2). HQS is weakly fluorescent in solution. Investigating the effect of various metal ions and solution conditions on the fluorescence properties of HQS is the purpose of the experiment. By designing appropriate experiments, you can explore how HQS might be useful as either a specific or nonspecific fluorescent reagent. 

The use of the complex with A -substituted-phenylstyrylacrylohydroxamic acid and Aliquat 336 for the determination of V in alloys, rock, environmental and clinical samples has recently been reported [1]. Studies on the complexation of V(V) with PAR on the solid phase of a fibrous sorbent filled with an anion exchanger were described [2]. The DL of of 3-4 ng ml V was achieved. The effect of modification of a solid support with 8-hydroxyquinoline and 8-hydroxyquinoline-5-sulfonic acid on analytical characteristics of the reaction of vanadium(V) with PAR on a solid phase was studied [3]. Extraction of V with the use of 3-hydroxy-2-(4-methoxyphenyl)-6-methyl-4//-chromen-4-one was employed to detect V in flue dust and steel [4]. 

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