scholarly journals Uv light impact on phthalates migration from children’s toys into artificial saliva

2021 ◽  
pp. 97-97
Author(s):  
Tatjana Andjelkovic ◽  
Danica Bogdanovic ◽  
Ivana Kostic-Kokic ◽  
Gordana Kocic ◽  
Radmila Pavlovic
Keyword(s):  
Sample Preparation ◽  
Extraction Method ◽  
Polar Solvent ◽  
Uv Light ◽  
Artificial Saliva ◽  
Migration Test ◽  
Plastic Toys ◽  
The Mean ◽  
High Polarity

Phthalates has been widely used in children's toys as plastic plasticizers and softeners. Therefore, attention should be paid to plastic toys, especially those that children can put in their mouths. In this paper quantification of five phthalates: DMP, DnBP, BBP, DEHP and DnOP in plastic toys, as well as irradiation of toys with UV light was performed. After sample preparation and development of the liquid-liquid phthalate extraction method from artificial saliva phthalate quantitative determination using the GC-MS technique was performed. The mean Recovery value for DEHP is 77.03 ? 2.76 %. The determination of phthalate in the recipient models (artificial saliva and n-hexane) was performed after 6, 15 and 30 days of the migration test using the GC-MS technique. Based on the known mass.% DEHP in the analyzed toys, the percentage of phthalate migration from each analyzed toy to the recipient model after 6, 15 and 30 days of the migration test was calculated. The results show that there is no significant migration of DEHP into artificial saliva, due to high polarity of the recipient (artificial saliva is polar), unlike n-hexane where the migration of DEHP is significant because it is a non-polar solvent.

scholarly journals DETERMINATION OF IODINE CONCENTRATION AND DISTRIBUTION IN RAT THYROID FOLLICLES BY ELECTRON-PROBE MICROANALYSIS

1969 ◽  
Vol 43 (1) ◽  
pp. 115-121 ◽  
Author(s):  
William L. Robison ◽  
David Davis
Keyword(s):  
Sample Preparation ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Freeze Drying ◽  
Iodine Concentration ◽  
Sodium Concentration ◽  
Thyroid Glands ◽  
The Mean ◽  
Rat Thyroid

The concentration and the distribution of iodine in various sized follicles of rat thyroid glands have been analyzed by electron-probe microanalysis. The results of the iodine analysis were grouped according to uncorrected lumen diameter size. No significant differences in iodine concentration were observed among the various size categories. When the results for all follicles from a given sample were pooled, the standard error of the mean was approximately 4%. Usually 40–50 follicles per animal were analyzed. The concentration of iodine ranged from 0.9 to 2.1% by weight among individual animals. Scanning pictures and step-scan analysis showed the iodine distribution to be quite uniform across the colloid area. Several techniques of sample preparation were used; they produced no significant differences in the iodine concentrations observed. Sodium concentration, also determined in all samples, was found to vary from 2 to 9% by weight. Because of the mobility of the sodium ion, its distribution was greatly affected by the method of sample preparation. The technique that best preserved the natural chemistry of the sample was that of freezing the tissue, sectioning, and then freeze-drying.

Liquid Chromatographic Determination of Salinomycin Sodium in Feed Premix and Biomass Samples

1987 ◽  
Vol 70 (3) ◽  
pp. 504-506 ◽  
Author(s):  
Gary P Dimenna ◽  
James A Creegan ◽  
Lennox B Turnbull ◽  
George J Wright
Keyword(s):  
Extraction Method ◽  
Chromatographic Determination ◽  
Turbidimetric Method ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic Determination ◽  
The Mean ◽  
Feed Premix ◽  
Liquid Chromatographic ◽  
Refractive Index Detection

Abstract A liquid chromatographic (LC) method has been developed for determination of sodium salinomycin (SS) in feed premix and biomass samples. SS is extracted from samples with acetonitrile, and the extract is diluted to volume. An aliquot is then injected directly into the chromatographic column, and refractive index detection is used to determine the presence of SS. The LC method proved to be both fast and specific; SS was quickly separated from lasalocid, monensin, and narasin. To test the efficiency of this extraction method, premix and biomass samples were spiked with SS. The mean recovery of SS from the spiked premix samples was 101.6%, and from the spiked biomass samples, 99.4%. Six premix samples were then assayed for SS in triplicate on 5 successive days, and 10 biomass samples were assayed for SS in triplicate on 3 different days. The coefficients of variation for the premix assay values ranged from 2.50 to 7.87%. For the biomass assay, CVs ranged from 0.9 to 3.5%. Premix and biomass samples were assayed for SS by this LC method in 2 laboratories and by a turbidimetric method using Bacillus subtilis in a third laboratory. The assay values obtained for SS were equivalent.

Determination of Nitroimidazole Metabolites in Swine and Turkey Muscle by Liquid Chromatography

1992 ◽  
Vol 75 (5) ◽  
pp. 790-795 ◽  
Author(s):  
Edward T Mallinson ◽  
A Carolyn Henry ◽  
Loyd Rowe
Keyword(s):  
Liquid Chromatography ◽  
Solid Phase Extraction ◽  
Extraction Method ◽  
Solid Phase ◽  
Phase Extraction ◽  
Recovery Curves ◽  
External Standard ◽  
The Mean ◽  
Initial Extraction

Abstract The method described can determine hydroxy dimetridazole and hydroxy ipronidazole in turkey and swine muscle tissue at levels of 2 ppb. After an initial extraction with ethyl acetate and subsequent evaporation, the samples are solvated in acid and back-extracted. A C18 solid-phase extraction is performed after neutralization of the acidic extract. The basis for quantitation was an external standard containing both analytes. After performing 10 recovery curves with blank control tissue spiked at 0, 1,2, and 4 ppb, the mean recoveries of hydroxy dimetridazole and hydroxy ipronidazole were 61.8 and 64.6%, respectively. Recovery variation was less than 20% for both analytes over all 10 curves. The performance of the extraction method was verified in tissues incurred through the dosing of live animals.

Simple extraction method and radioimmunoassay for somatostatin in human plasma.

1981 ◽  
Vol 27 (6) ◽  
pp. 888-891 ◽  
Author(s):  
T L Peeters ◽  
Y Depraetere ◽  
G R Vantrappen
Keyword(s):  
Human Plasma ◽  
Plasma Proteins ◽  
Extraction Method ◽  
Plasma Samples ◽  
Analytical Recovery ◽  
Simple Extraction ◽  
The Mean ◽  
Radioimmunological Determination ◽  
Dilution Curves

Abstract Interference by human plasma proteins in the radioimmunological determination of somatostatin was eliminated by subjecting plasma samples to acid--ethanol precipitation. The assay was performed on the lyophilized supernate from 300 microliters of human plasma, with reagents that are commercially available. Sensitivity was 2.6 pg, corresponding to 8.7 ng/L of plasma. The intra-assay CV was 8%; the inter-assay CV was 12% for a low (30 ng/L) and 15% for a high (100 ng/L) standard. The mean analytical recovery of exogenous somatostatin from plasma was 95%, and the standard synthetic cyclic somatostatin showed parallel dilution curves with extracted plasma samples. Neither gastrin HG-17 and HG-34, pentagastrin, secretin, glucagon, vasoactive intestinal polypeptide, substance P, nor pancreatic polypeptide interfered in the assay system. Mean immunoreactive somatostatin in 20 normal fasting subjects was 31.5 (SD 15.6) ng/L and ranged from 14 to 67 ng/L.

scholarly journals Development of a HPLC Method for the Quantitative Determination of Capsaicin in Collagen Sponge

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Chun-Lian Guo ◽  
Hong-Ying Chen ◽  
Bi-Ling Cui ◽  
Yu-Huan Chen ◽  
Yan-Fang Zhou ◽  
...  
Keyword(s):  
Ultrasonic Wave ◽  
Extraction Method ◽  
Chromatographic Method ◽  
Pharmaceutical Products ◽  
Hplc Method ◽  
Collagen Sponge ◽  
Hplc Assay ◽  
The Mean ◽  
Perfect Recovery

Controlling the concentration of drugs in pharmaceutical products is essential to patient’s safety. In this study, a simple and sensitive HPLC method is developed to quantitatively analyze capsaicin in collagen sponge. The capsaicin from sponge was extracted for 30 min with ultrasonic wave extraction technique and methanol was used as solvent. The chromatographic method was performed by using isocratic system composed of acetonitrile-water (70 : 30) with a flow rate of 1 mL/min and the detection wavelength was at 280 nm. Capsaicin can be successfully separated with good linearity (the regression equation isA= 9.7182C+ 0.8547;R2= 1.0) and perfect recovery (99.72%). The mean capsaicin concentration in collagen sponge was 49.32 mg/g (RSD = 1.30%;n= 3). In conclusion, the ultrasonic wave extraction method is simple and the extracting efficiency is high. The HPLC assay has excellent sensitivity and specificity and is a convenient method for capsaicin detection in collagen sponge. This paper firstly discusses the quantitative analysis of capsaicin in collagen sponge.

Automated Fluorometric Determination of Thiamine and Riboflavin in Infant Formulas

1979 ◽  
Vol 62 (3) ◽  
pp. 642-647
Author(s):  
Walter E Dunbar ◽  
Kenneth E Stevenson
Keyword(s):  
Sample Preparation ◽  
Infant Formulas ◽  
Fluorometric Method ◽  
Fluorometric Determination ◽  
Automated Method ◽  
Coefficients Of Variation ◽  
Manual Methods ◽  
The Mean ◽  
Better Than

Abstract Commercial infant formulas were analyzed simultaneously for thiamine and riboflavin by an automated fluorometric method and by the AOAC manual fluorometric methods. For 10 products, the mean thiamine and riboflavin results determined using the automated method ranged from 104 to 113% and 90 to 112%, respectively, of those by the AOAC manual methods. The coefficients of variation for thiamine and riboflavin ranged from 1.05 to 3.90% and 0.60 to 2.48%, respectively, for the automated method, and 1.48 to 3.86% and 0.69 to 10.9%, respectively, for the manual methods. Using the automated method, mean recoveries of thiamine and riboflavin added to samples were 103 and 104%, respectively. The automated method used a common sample preparation to determine both thiamine and riboflavin, and gave results equivalent to, or better than, those obtained by the manual methods.

Sign in / Sign up

Export Citation Format

Share Document