The diverse applicability of diazo compounds as versatile reagents has enlarged the chemical toolbox in organic synthesis. Over past few decades, transition metal-catalyzed compound activation ignited classical synthetic methodology via utilizing highly reactive metal carbenoid species. Many reviews have also appeared literature which discloses advantage and disadvantages compound. Recently, tr...

A rapid and sensitive flow-injection spectrophotometric method is proposed for the determination of sulfadiazine and sulfamethoxazole. This method is based on the diazotization of sulfonamide with sodium nitrite, and a coupling reaction of the diazo-compound with alpha-naphthylamine. The optimum experimental conditions are obtained by using the controlled and weighted centroid simplex method. T...

We evaluated the results of two surveys of neonatal bilirubin determinations in 66 Slovakian clinical chemistry laboratories. Identical control samples prepared as described by Vink (Clin. Chem. 33 (1987) 1817-1821) and commercially available control serum were used for both surveys. These control samples were analysed in the participating laboratories using various modifications of diazo techn...

A colorimetric sensor for nitrite ion with high selectivity and sensitivity by unmodified citrate-capped gold nanoparticles (Au NPs) is presented. Recognition of nitrite is developed on the basis of a highly specific diazo reaction between nitrite and phenylenediamine (PDA). PDA caused the Au NPs to aggregate owing to the strong covalent NH-Au bond, with a clear color change of solution from re...

In the present study, a series of azo derivatives (TR-1 to TR-9) have been synthesised via diazo-coupling approach between substituted aromatic amines with phenol or naphthol derivatives. The compounds were evaluated for their therapeutic applications against alpha-glucosidase (anti-diabetic) and pathogenic bacterial strains E. coli (gram-negative), S. aureus (gram-positive), (gram-positive) dr...

The hydrogen peroxide produced from glucose by glucose oxidase action at pH 7 is determined by the peroxidase oxidative coupling of N,N-diethylaniline with 4-amino-antipyrine. A 20-al sample of plasma or serum is reacted at room temperature for 10 mm. The sensitivity of the method is such that 60 zg of glucose (300 mg/dl) in a final volume of 5 ml gives an absorbance of 0.8 at 553 nm with a 1-c...

Delta bilirubin (B delta), isolated from serum, has an absorption maximum near 440 nm and a molar absorptivity of 72,000 L mol-1cm-1 in either Tris HCl (0.1 mol/L, pH 8.5) or phosphate (0.13 mol/L, pH 7.4) buffer. This absorptivity exceeds by approximately 50% and 59%, respectively, that of unconjugated bilirubin in the same buffers. This finding suggests that substantial errors can be incurred...

The concept of amplitude-modulated multiplexed flow analysis has been extended to the simultaneous determination of multiple analytes in a sample. A sample solution containing nitrite and nitrate ions is delivered from two channels, but the flow rates are varied at different frequencies. One of the channels has a reduction column for converting nitrate ions to nitrite ions. Downstream, the abso...