Spectrophotometric determination of Cu2+ and Pd2+ ions using some acetyl formazans

The formazan compounds have received great attention due to their biological activity and dyeing properties for a variety of fabrics [1,2] Due to their skeleton as good carriers of pi-bonding and chelating properties, they have been used as analytical reagents [3]Malevannyi and Shikhova [4] reported a Spectrophotometric method for the determination of Mn[2+] using 1,5-bis [2-hydroxy-5-sulfophenyl]-3-acetylformazan. Bigma et al. [5] developed a Spectrophotometric procedure for the microdetennination of Cu in Mg metal and some of its Mg alloys using 1,5-di [2-hydroxy-4-nitrophenyl]- 3- acetyl-formazan. Christian [6] reported a method for the determination of lithium using TMC-Crown formazan. Novel pyridyl formazan derivatives were synthesized and the characteristic analytical properties of their complex compounds with various transition metal ions were investigated [7]. The present investigation deals with the use of l,5-diphenyl-3- acetylformazan [I] and l,5-bis[o-carboxyphenyl] -3- acetylformazan [II] for the Spectrophotometric determination of Cu and Pd

Nosocomial blood stream infection in NICN Mansoura University Hospital

We detected 37.24% nosocomial infection rate [292 infection in 205 infants] among 784 neonates hospitalized for more than 48 hours in Neonatal Intensive Care Unit [NICU] in Mansoura University Hospital during 12 months of surveillance. Blood stream infection [BSI] accounted for24.74%of the total infections. Staphylococcus epidermidis [20.61%], E. coli [16.94%] Staphylococcus aureus [14.43%] and other Gram negative bacilli [32.92%] were the most common organisms isolated. Nosocomial infection rates were significantly higher in infants with low birth weight [<2,500 g]. Nosocomial BSI was more common in neonates with intravenous lines

Potentiometric conductometric and spectrophotometric studies on co2+, Ni2+, Cu2+, Pd2+ and Pt2+ complexes with some naphthol derivatives

The ionization constants [pka] of some naphthol derivatives were determined potentiometrically in 40 percent ethanolic solution. The stability constants of divalent Co, Ni, Cu, Pd and Pt complexes with naphthol derivatives were determined potentiometrically, log Beta[1] and Log Beta[2] values being calculated. The correlation between the basicity of the ligands and stability of complexes is discussed. Conductometric titrations of divalent Co, Ni, Cu and Pt with the naphthol derivatives were carried out to give further insight into the stoichiometric composition of the complexes formed in solutions. The divalent Ni and Pd complexes with NNWA were studied spectrophotometrically and the stoichiometries of the complexes formed were established. The results indicate that all ligands form 1:1 and 1:2 [M: L] complexes and the influence of pH. time, sequence of addition and foreign ions on the formation of the complexes was studied. Beer's law was satisfactorily obeyed up to 6 ppm and 7 ppm for Ni and Pd respectively

Physicochemical studies on some 1,35-triphenylformazan derivatives and their complexes

The stability constants of the complexes formed between divalent Co, Ni, Cu and Zn ions with 1, 3, 5- triphenylformazan derivatives were determined potentiometrically and log Beta [1] and Log Beta[2] values calculated. The relations between the stability constants of the complexes and their ionization potential, electronegativity, ionic radius and atomic number were investigated. The effect of the substituents present on the ligand molecules is also considered, the relationships being treated statistically. The values indicate that Cu-complexes are highly susceptible to the influence of substituents on the one or five positioned phenyl moiety. The values of Delta G, Delta H and Delta S of the complexes are determined. The conductimetric titrations of the above divalent ions with formazan derivatives show breaks at molar ratios 1:1 and 1:2 which is in accordance with the results obtained from pH-metric titrations

Optical properties of PVA doped with CoCl2

Optical absorption measurements in the spectral range 4000-50000 cm[-1], were performed on cast thin films of polyvinyl alcohol[PVA] and its composites with cobalt chloride [CoCl [2]. Identification of the structure and assignments of energy bands have been derived in terms of the ligand field theory. A mechanism based on the equilibrium between six-coordinated and four- coordinated symmetry is proposed to account for the obtained spectra. Such equilibrium is attributed to a small difference between the stabilization energies, and the symmetry is found to be altered with cobalt chloride concentrations

Chelates of CE [III], Th [IV] and UO2 [VI] with some schiff bases

SCHIFF bases are well known to have pronounced biological activities. Their ready synthesis and active properties have contributed greatly to their popularity and to the study of many biological systems [1-3]. Metal complexes of Schiff bases are studied extensively due to synthetic flexibility of these compounds and their selectivity as well as sensitivity towards several metal ions. Several reviews have been devoted to coordination chemistry of Schiff base metal complexes [4-7] Dioxouranium [VI] complexes [1:2] of some salicylaldehyde Schiff bases have been synthesized [8] Anthranilic acid Schiff base complexes with Th [IV], UO[2] [VI], La [III], Ce [III] and Zr [IV] have been isolated and studied by several techniques [9] The coordination of Th [IV] and UO[2] [VI] with a number of mono and polydentate Schiff bases has been studied. Several bi-and trinuclear complexes have been investigated [10]. The present article deals with the evaluation of the ionization constants of Schiff bases [I], [II] and [III] and the stability constants of their complexes with Ce [III], Th [IV] and UO[2]>2 [VI] ions. The solid complexes which could be isolated were also investigated by elemental analysis and IR spectroscopy

Electrical conductivity, Spectroscopic and thermal studies on chelates of SPADNS with some transition metals

The solid complexes of SPADNS 2-[P-sulfonyl] -1,8-dihydroxynaphthalene 3,6-disulfonic acid trisodium salt] with Cr [III], Mn [II], Co [II], Ni [II] and Cu [II] were prepared and subjected to elemental analysis, IR, thermogravimetric and electrical conductivity studies. The optical properties as well as the type of coordination and its role in the conduction mechanism were also studied. Racah constants B and the activation energies delta E were determined and correlated with the covalent characters of the metal-SPANDS bonds within the chelates. The study revealed that both Co and Ni are in the divalent state and are octahedrally coordinated, while Cr is in the trivalent and is also six-coordinated

Tinea corporis, clinical and mycological study in Dakahlia

Our study was carried out in an attempt to classify and identify the causative fungi of tinea corporis as well as the incidence of the disease in our locality Trichophyton rubrum was the commonest isolated dermatophyte [35.75%]. Trichophyton violaceum comes next in frequency [16.58%], followed by trichophyton metagrophyte and Epidermophyton floccosum [7.77%], Trichophyton schoenleinii [4.66%] while trichophyton tonsurans [0.25%], trichophyton verrucosum [1.56%] and Microsporum canis [0.52%] were at the lowest end of the list, Candida were isolated from 24.87% of positive cases

Use of iodine, iodates, periodate or dichromate in the potentiometric determination of dithionite and disulphite

A new potentiometric method is reported for the accurate determination of dithionite and disulphite using iodine, iodate, periodate, or dichromate. When iodine is used as oxidant the iodide produced is determined by titration with mercury [II] nitrate solution. When iodate, periodate or dichromate are used as oxidants a known excess of the oxidant is used, then after reaction a known excess of iodide solution is added and unreacted iodide is determined by titration with mercury [II] nitrate solution. All end points were determined potentiometrically using silver amalgam standard calomel electrodes. Potential breaks averaged 322 and 383 mV/0.1 ml for titrants for dithionite and disulphite determinations respectively and were sharp enough for precise determination of end points over a wide range of concentrations and even with low concentrations of the analysts

Applications involving iodide and persulphate: use of persulphate and iodide in the potentiometric determination of arsenite, phosphite, hypophosphite and quinol

A new reliable potentiometric method is given for the determination of persulphate based on reduction with iodide and titration of unreacted iodide with Hg [II] using silver amalgam as the indicator electrode in conjunction with a standard calomel electrode over a wide range of concentrations. The end point potential breaks amounted to 365-440 mV per 0.1 ml titrant and hence the high accuracy of the present method. Rapid and accurate potentiometric methods have been developed for estimation of arsenite, phosphite, hypophosphite and quinol based on oxidation with persulphate and subsequent determination of unreacted pxidant potentiometrically as mentioned above. The results are quite satisfactory and the end points are well defined with very sharp potential breaks ranging from 200 to 398 mV per 0.1 ml of mercury [II]

Antibiotic concentration into the sinus secretions in case of chronic maxillary sinusitis

The ability of different antibiotics to penetrate into the diseased maxillary sinus mucosa and to sinus secretion was investigated in patients with chronic maxillary sinusitis. 50 patients were given a course either of rifampicin [18 patients], cephalexin [16 patient] or ampicillin [16 patient], 60 aspirated, and 90 irrigated secretion samples were assessed for determination of the concentration of these antibiotice. The highest concentration was achieved with rifampicin and the lowest was with cephalexin

Intekoital and foecal escherichia coli o-serotypes and its relationship to bacteriuria during pregnancy

Cultures from interoital swab, ectal swab and urine specimen elected from 130 patients who had a history of recurrent urinary tract infection. The intertal and rectal E. coli count increased significantly with the urinary count. The prognostic importance of the interoital swab cultures is shown during the follow up by the fact that 60% of the cases develop urinary tract infection when the original interiotal swab E. coli, while only 40% develop urinary tract infection when the initial interoital swab was negative. This difference is statistically significant. The infections were found to occur early in cases with initial E. coli, Patients who developed urinary tract infection were significantly older. There was a higher incidence of corrospondence between the urinary E. coli and the faecal and interoital E. coli strains in symptomatic cases than in asymptomatic bacteriuria indicating that the symptomatic urinary tract infections were not preceeded by asymptomatic bacteriuria. The most frequent E. coli O-group was 0-6. This suggests that E. coli 0-6 group is pathogenic for urinary tract. E. coli 0-6 showed corrospondence between urinary, interiotal and faecal isolates. The results suggest that the availability of E. coli in the vestibular and recte flora constitutes a permissive factor for ascending urinary tract infections to occur

Mutagenic effect of primovlar contraceptive tablets on E. coli

This study was carried out to determine if there is any mutagenic effect for Primovlar, the oral contraceptive tablets, on E. coil isolated from normal vagina. It was found that primovar stimulated E. coli growth in low doses and inhibited it in high doses in both complete minimal media. Higher percentage of mutants were obtained following the drug treatment than spontaneously with higher percentage of uracil-requiring mutants. This study proved that the induced uracil-requiring mutants were functional indicating the possibility of carcinogenicity for the drug