Biomedical subjects

I Kuselman

Publications and source records attributed to I Kuselman.

7 recordsLinked to original sources

PubMed2001

Distributions of results of cetirizine dihydrochloride assay in bulk material.

The distribution of the cetirizine dihydrochloride assay results in correlation with the pharmacopoeia limits is analyzed. The data for analysis were obtained at Chemagis Ltd., Israel, for 13 batches during a year in two laboratories by five analysts using three different titroprocessors (total 114 results of the determination). The hypothesis on the normal distribution of the data was tested using omega(2)-criterion and accepted at the level of confidence 0.90. A control chart is designed for indication of warning and action limits of the determination results and for diagnoses of outliers in the further titrations. The distribution of the analyte content in different batches and the distributions of the titration results at the pharmacopoeia limits were plotted. The probabilities of the erroneous decisions of Type 1 and Type 2 on the batch quality were calculated from these distributions.

Anti-Allergic Agents↗

PubMed1999

Water determination in drugs containing thiols.

A new rapid analytical method is applied for water determination in alpha-Mono-thioglycerol and Captopril tablets containing thiols, and therefore, not amenable for direct Karl Fischer titration. The method is based on the consecutive titration first of thiol by a novel reagent, and then of water by a conventional K. Fischer reagent in the same sample and cell with the electrometric 'dead-stop' location of the end point in both titrations. The new reagent consists of iodine, potassium iodide and sodium acetate in non-aqueous medium. Estimated repeatability and accuracy of both water and thiol determinations are satisfactory.

Captopril↗

PubMed1999

Water determination in drugs containing ascorbic acid.

A new rapid analytical method was applied for water determination in tablets of vitamin C, Ce De Calcium Veterinary, and C-Tamin-500 containing ascorbic acid and therefore is not amenable for direct Karl Fischer (KF) titration. The method is based on the consecutive titration first of ascorbic acid by a novel reagent and then of water by a conventional KF reagent (KFR) in the same sample and cell with the electrometric "dead-stop" location of the end point in both titrations. The new reagent consists of iodine, potassium iodide, and sodium acetate in nonaqueous medium. Estimated repeatability and accuracy of both water and ascorbic acid determination are satisfactory.

Ascorbic Acid↗

PubMed1996

Microcell for anodic stripping voltammetry of trace metals.

A microcell for batch injection stripping voltammetry of trace metals with the use of a rotating disk working electrode has been developed and tested for samples of 0.2-0.3 mL. The detection limits for Pb(2+), Cd(2+) and Zn(2+) are 0.03 ppb and 0.3 for a deposition time of 5.0 and 0.5 min, respectively.

Journal Article↗

PubMedDate not supplied

Simultaneous determination of water and enediols or thiols in chemical products and drugs not amenable to direct Karl Fischer titration.

A method proposed for determining water and enediols or thiols is based on consecutive titration of the enediols or thiols by a novel reagent and of water by the conventional Karl Fischer reagent in the same cell. The time for both titrations is 8-20 min. The novel reagent consists of iodine, sodium acetate as a base, and potassium iodide in a nonaqueous solvent system. The method is applicable for quality control of chemical products and drugs during their production and trade.

Ascorbic Acid↗

PubMedDate not supplied

pH-metric determination of acid numbers of petroleum oils without titration.

A pH-metric method was developed for determination of the acid numbers of oils containing organic and inorganic acids at levels <0.1 mg KOH/g oil. The method is based on rapid and complete extraction of acids from a test portion of oil into a special reagent, and measurement of the conditional pH of the mixture "oil-reagent" by a glass electrode. The method uses nontoxic reagents, is not time and labor consuming, and is cheap and simple enough for automation.

Electrodes↗

PubMedDate not supplied

pH-metric determination of the acid value of vegetable oils without titration.

The acid value (AV) of vegetable oils is determined without titration by using a new reagent consisting of triethanolamine in a solution of water and isopropyl alcohol. When the oil sample is mixed with the reagent in the pH-metric cell, free fatty acids from the sample are extracted into the reagent (3-4 min). The initial pH, called conditional pH'1, is measured, a standard acid (HCl) is added, and the final pH, pH'2, is measured. AV is calculated from the difference between pH'1 and pH'2. The method is applicable for quality control of vegetable oils during their production, trade, and use.

2-Propanol↗