THE SEPARATION AND DETERMINATION OF THE ALKALI METALS, USING PERCHLORIC ACID. I. THE SOLUBILITIES OF THE PERCHLORATES OF THE ALKALI METALS IN MIXED ORGANIC SOLVENTS

1925 ◽  
Vol 47 (3) ◽  
pp. 762-769 ◽  
Author(s):  
G. Frederick Smith
1960 ◽  
Vol XXXV (I) ◽  
pp. 34-48 ◽  
Author(s):  
Gerd Ittrich

ABSTRACT A series of organic solvents and phenol derivatives have been examined for the extraction of the pink Kober-colour complex. Optimal results could be achieved for fluorimetry by a solution of 2 % (w/v) p-nitrophenol and 1 % (v/v) ethanol in acetylenetetrabromide, when the green mercury line (546 mμ was used as primary light. The sensitivity, stability and specificity have been improved, compared with the previously described reaction. By changing the sequence of purification steps and by reducing the volume of the urine sample (5 ml) the method for the determination of total oestrogens has been simplified. Approximately 10 determinations can be done within 3–4 hours by one person. Recovery experiments and comparative determinations with a previously described method have been carried out. The excretion of total oestrogens in a complete menstrual cycle is determined with the described method.


2014 ◽  
Vol 32 (11) ◽  
pp. 1251
Author(s):  
Jing DA ◽  
Xianglu HUANG ◽  
Gangli WANG ◽  
Jin CAO ◽  
Qingsheng ZHANG

1987 ◽  
Vol 33 (8) ◽  
pp. 1427-1430 ◽  
Author(s):  
R Sakuma ◽  
T Nishina ◽  
M Kitamura

Abstract We evaluated six deproteinizing methods for determination of uric acid in serum by "high-performance" liquid chromatography with ultraviolet detection: those involving zinc hydroxide, sodium tungstate, trichloroacetic acid, perchloric acid, acetonitrile, and centrifugal ultrafiltration (with Amicon MPS-1 devices). We used a Toyosoda ODS-120A reversed-phase column. The mobile phase was sodium phosphate buffer (40 mmol/L, pH 2.2) containing 20 mL of methanol per liter. Absorbance of the eluate was monitored at 284 nm. The precipitation method with perchloric acid gave high recoveries of uric acid and good precision, and results agreed with those by the uricase-catalase method of Kageyama (Clin Chim Acta 1971;31:421-6).


2016 ◽  
Vol 99 (6) ◽  
pp. 1533-1536 ◽  
Author(s):  
Jéssica Sayuri Hisano Natori ◽  
Eliane Gandolpho Tótoli ◽  
Hérida Regina Nunes Salgado

Abstract Norfloxacin is a broad-spectrum antimicrobial agent, widely used in humans and animals for the treatment of urinary tract infections. It is a second-generation fluoroquinolone. Several analytical methods to analyze norfloxacin have been described in the literature. However, most of them are complex and require the use of large amounts of organic solvents. This paper describes the development and validation of a green analytical method for the determination of norfloxacin in raw material by FTIR spectrophotometry. This method does not require the use of organic solvents, minimizing waste generation in the process and its environmental impacts. The development of methods that promote the reduction, prevention, or elimination of waste generation has become highly attractive to the pharmaceutical industry because of the growing demand from civil society and government authorities for environmentally friendly products and services. The FTIR spectrophotometry method was validated according to International Conference on Harmonization guidelines, showing adequate linearity (r = 0.9936), precision, accuracy, and robustness. This validated method can be used as an environmentally friendly alternative for the quantification of norfloxacin in raw material in QC routine analysis.


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