Improved method for determination of 2,2-dichloropropionic acid in chlorinated propionic acid by use of buffered mercuric nitrate solution

1971 ◽  
Vol 19 (1) ◽  
pp. 189-191
Author(s):  
Roland P. Marquardt
Keyword(s):  
Propionic Acid ◽  
Nitrate Solution ◽  
Improved Method ◽  
Mercuric Nitrate

Improved Colorimetric Determination of Salicylic Acid and Its Metabolites in Urine

1975 ◽  
Vol 21 (8) ◽  
pp. 1167-1168 ◽  
Author(s):  
Nagy A Farid ◽  
Gordon S Born ◽  
Wayne V Kessler ◽  
S M Shaw ◽  
W E Lange
Keyword(s):  
Salicylic Acid ◽  
Sodium Salicylate ◽  
Nitrate Solution ◽  
Ethylene Dichloride ◽  
Ferric Nitrate ◽  
Colorimetric Determination ◽  
Improved Method ◽  
Salicyluric Acid ◽  
Sample Recovery

Abstract We describe an improvement in the Levy and Procknal method [J. Pharm. Sci. 57, 1330 (1968)] for determination of salicylic acid and its metabolites in urine. Salicylic acid and salicyluric acid are successively extracted from 1 or 2 ml of urine (acidified with HCl) by two 10-ml portions each of carbon tetrachloride and ethylene dichloride. The extracts of each solvent are shaken with 5 ml of ferric nitrate solution (a 10-fold dilution of 17 g of Fe(NO3)3·9H2O in 1 liter of 70 mmol/liter HNO3). The aqueous phases are centrifuged and their absorbances measured at 530 nm. For total salicylate, 3 ml of urine and 3 ml of HCl are heated in a partially evacuated serum vial at 100 °C for 16 h and then salicylic acid is assayed in the hydrolyzed sample. Recovery of a weighed oral dose of sodium salicylate in urine was 105.4%; it was 127.9% by the Levy and Procknal method for the same sample. The improved method is faster and more accurate.

SERUM TRIIODOTHYRONINE DETERMINATION BY SATURATION ANALYSIS

1973 ◽  
Vol 72 (4) ◽  
pp. 714-726 ◽  
Author(s):  
A. Burger ◽  
B. Miller ◽  
C. Sakoloff ◽  
M. B. Vallotton
Keyword(s):  
Ionic Strength ◽  
Limit Of Detection ◽  
Improved Method ◽  
Accuracy Of Measurement ◽  
Tracer Amount ◽  
The Mean ◽  
Physiological Values ◽  
Hyperthyroid Patients ◽  
Solvent Blank

ABSTRACT An improved method for the determination of serum triiodothyronine (T3) has been developed. After addition of a tracer amount of the hormone, T3 was extracted from 1 ml serum under conditions of pH and ionic strength which favoured T3 extraction (89%) over thyroxine (T4) extraction (58%). Chromatography of the extracted material on Sephadex LH-20 separated T3 completely from residual T4. The T3 eluate was dried, then re-dissolved in 0.5 ml NaOH 0.04 n. To 0.2 ml duplicate aliquots, a standard amount of TBG was added for the competitive protein analysis. After one hour incubation at 4°C, separation of bound from free T3 was achieved on small Sephadex G-25 columns. Overall recovery was 67 ± 10.8% and correction for the loss was made. The solvent blank was 37 ± 27 (sd) ng/100 ml. Accuracy of measurement of known quantities of T3 added to serum was 98.4%. The coefficient of variation within the assay was 6.2% and between the assays it was 11.4%. The limit of detection (0.1 ng) corresponded to a concentration of 25 ng/100 ml. T4 added to serum did not interfere with T3 determination until high non-physiological values were reached. The mean ± sd serum T3 in 54 euthyroid subjects was 153 ± 58 ng/100 ml and in 24 hyperthyroid patients it was 428 ±186 ng/100 ml; 4 out of the 24 hyperthyroid values were within 2 sd of the mean euthyroid group. All the values found in the euthyroid group were well above the limit of detection of the method.

An Improved Method for the Determination of Metabolic Fecal P

1957 ◽  
Vol 16 (1) ◽  
pp. 201-206 ◽  
Author(s):  
J. R. Luick ◽  
G. P. Lofgreen
Keyword(s):  
Improved Method

Improved Method for the Determination of Ethylenebisdithiocarbamate Residues in Plants, Fruits, and Vegetables

1967 ◽  
Vol 50 (5) ◽  
pp. 1102-1108
Author(s):  
Charles F Gordon ◽  
Richard J Schuckert ◽  
William E Bornak
Keyword(s):  
Sulfuric Acid ◽  
Fruits And Vegetables ◽  
Analytical Procedure ◽  
Improved Method ◽  
Modified Method ◽  
Fungicide Residues ◽  
Crop Types ◽  
Large Representative

Abstract A modified method for the determination of dithiocarbamate fungicide residues on crops is presented. A large representative subsample of the frozen crop is blended in ice-cold deaerated water and an aliquot of the homogenate is added to the analytical apparatus containing hot 5 0% sulfuric acid. Dithiocarbamates are decomposed to evolve CS2 which is removed by a continuous gentle air-sweep from the digestion flask. Variations in technique allow the analysis of dithiocarbamate fungicide residues in several ranges, 1-10, 10-200, and 200-1000 /ig maneb. Recoveries from a wide variety of crops averaged 70 to 103%. Certain crop types present low recoveries and/or high apparent control values, but modifications in the analytical procedure are successful in solving these problems.

Qualitative and quantitative determination of trace aldehydes and ketones in food preservative propionic acid for quality improvement

2021 ◽  
Author(s):  
Yiwen Cao ◽  
Shenjie Zhu ◽  
Lin Zhang ◽  
Qun Cui ◽  
Haiyan Wang
Keyword(s):  
Quality Improvement ◽  
Quantitative Analysis ◽  
Quantitative Determination ◽  
Propionic Acid ◽  
Qualitative And Quantitative Analysis ◽  
Food Preservative ◽  
Qualitative And Quantitative ◽  
Aldehydes And Ketones ◽  
Aldehyde Content

Aiming at the difficulty in qualitative and quantitative analysis of trace compositions in food preservative propionic acid, the trace compositions and the key components influencing the total aldehyde content in...

Sign in / Sign up

Export Citation Format

Share Document