Determination of Free and Total Choline and Carnitine in Infant Formula and Adult/Pediatric Nutritional Formula by Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS): Single-Laboratory Validation, First Action 2015.10

2016 ◽  
Vol 99 (1) ◽  
pp. 204-209 ◽  
Author(s):  
David J Ellingson ◽  
Jeffrey J Shippar ◽  
Justin M Gilmore
Keyword(s):  
Infant Formula ◽  
Accurate Determination ◽  
Strong Cation Exchange ◽  
Microwave Hydrolysis ◽  
Liquid Chromatography Tandem Mass ◽  
Total Analysis ◽  
Acidic Conditions ◽  
Single Laboratory ◽  
Ammonium Compounds

Abstract Analytical methods for the analysis of both L-carnitine and choline are needed for reliable and accurate determination in infant formula and adult/pediatric nutritional formula. These compounds are different in how they are utilized by the human body, but are structurally similar. L-carnitine and choline are quaternary ammonium compounds, enabling both to be retained under acidic conditions with strong cation exchange (SCX) chromatography. This method analyzes both compounds simultaneously as either the free forms or as a total amount that includes bound sources such as phosphatidylcholine or acetylcarnitine. The free analysis consists of water extraction and analysis by LC/MS/MS, while the total analysis consists of extraction by acid assisted microwave hydrolysis and analysis by LC/MS/MS. Calibration standards used for calculations are extracted with all samples in the batch. A single laboratory validation (SLV) was performed following the guidelines of the AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) utilizing the kit of materials provided. The results achieved meet the requirements of SMPR 2012.010 and 2012.013 for L-carnitine and total choline, respectively.

2-Monochloropropanediol (2-MCPD), 3-Monochloropropanediol (3-MCPD), and Glycidol in Infant and Adult/Pediatric Nutritional Formula: Single-Laboratory Validation, First Action 2018.12

2019 ◽  
Vol 102 (4) ◽  
pp. 1205-1220 ◽  
Author(s):  
Jan Kuhlmann
Keyword(s):  
Fatty Acid ◽  
Infant Formula ◽  
Edible Oils ◽  
Accurate Determination ◽  
Fatty Acid Esters ◽  
Method Performance ◽  
Relative Standard ◽  
Single Laboratory ◽  
Acid Esters

Abstract Background: Fatty acid esters of glycidol, 2-Monochloropropanediol (MCPD), and 3-MCPD are heat-induced foodborne processing contaminants with possible adverse health effects. These compounds occur frequently in refined edible oils. Consequently, glycidyl esters and 2- and 3-MCPD esters might also be present in foods that contain refined edible oils. Objective: This manuscript describes the single-laboratory validation of an analytical method for the quantitative determination of glycidol, 2-MCPD, and 3-MCPD present as fatty acid esters or as free 2- or 3-MCPD in infant and adult/pediatric nutritional formula. Methods: Technically, the presented method is based on the combination of a Heat-Ultrasound Pressure-supported Solvent Extraction and a GC–MS determination of glycidol, 2-MCPD, and 3-MCPD. From a chemical perspective, the method includes an alkaline catalyzed transesterification, conversion of the unstable glycidol into monobromopropanediol, and the parallel derivatization of all analytes with phenylboronic acid. Results: Validation results showed that method linearity for all analytes in powdered and liquid infant formula ranged from 0.9981 to 0.9999 (n = 18). Repeatability relative standard deviation values for concentration levels between 1.3 μg/kg and 331 μg/kg were in the range of 1 to 12%. Relative recoveries were found to be between 93 and 107%. The analytes were quantifiable down to 5–10 μg/kg in powdered samples and 1–2 μg/kg in liquid samples. Conclusions: The reported results met actual AOAC Standard Method Performance Requirements. Highlights: In terms of consumer protection, the presented method is a novel approach for the sensitive and accurate determination of glycidol, 2-MCPD, and 3-MCPD in infant formula and related foodstuffs.

Determination of Sodium Fluoroacetate in Dairy Powders by Liquid Chromatography–Tandem Mass Spectrometry: Single-Laboratory Validation, First Action 2015.02

2016 ◽  
Vol 99 (1) ◽  
pp. 242-251 ◽  
Author(s):  
Lauren M Fleury ◽  
Bryan G Scahill ◽  
Rilka Taskova
Keyword(s):  
Infant Formula ◽  
Intermediate Precision ◽  
Method Performance ◽  
Expert Review ◽  
Liquid Chromatography Tandem Mass ◽  
Expert Review Panel ◽  
Single Laboratory ◽  
Lc Tandem Ms ◽  
Dairy Powders

Abstract A single-laboratory validation (SLV) study was conducted for the determination of sodium fluoroacetate in dairy powders by LC-tandem MS (LC-MS/MS). Linearity of response was confirmed by analysis of samples fortified over the concentration range 0.10–100 μg/kg. The LOD was estimated to be 0.028 μg/kg (0.028 ppb) from the SD of the measured concentrations of infant formula samples fortified at 0.10 μg/kg. The corresponding LOQ calculates at 0.085 μg/kg (0.085 ppb), which ensures excellent reliability of quantification at the limit of reporting of 1.0 μg/kg (1 ppb). Repeatability and intermediate precision were estimated from the SD of the recovery of samples fortified at 0.075, 0.10, 0.20, 0.50, 1.0, and 10.0 μg/kg. The previously mentioned method performance values were established using a representative stage 2 (6–12 months) bovine infant formula, and the robustness of the method was tested by the analysis of 107 unique dairy powders and formulations fortified at 1.0 μg/kg. The data collected in this study satisfy the requirements of SLV studies established by the AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN), and the method was awarded First Action Official MethodSM status by the AOAC Expert Review Panel on SPIFAN Nutrient Methods (Contaminants) on March 17, 2015.

Determination of total proteinogenic amino acids and taurine by pre-column derivatisation and UHPLC: Single Laboratory Validation, First Action 2019.09

2020 ◽  
Author(s):  
George Joseph ◽  
Asha Varughese ◽  
Ann Daniel
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Infant Formula ◽  
Retention Time ◽  
Sulfonic Acid ◽  
Internal Standard ◽  
The Other ◽  
Method Performance ◽  
Single Laboratory

Abstract Background A method has been developed and validated for selective, accurate and precise determination of total proteinogenic amino acids and taurine from Infant Formula and Adult/Pediatric Nutritional Formulas (powders, ready-to-feed liquids, and liquid concentrates). The method was reviewed by the AOAC INTERNATIONAL SPIFAN Expert Review Panel (ERP) during the 133rd AOAC Annual Meeting & Expo on September 7, 2019 in Denver, CO, USA and was recommended to First Action Official MethodsSM status. Objective The method involves protein hydrolysis to amino acids, a simple pre-column derivatisation of amino acids and separation of derivatised amino acids by UHPLC. The quantification of amino acids is performed by multi-point calibration using norvaline as the internal standard. The analytical method is capable of quantitative determination for 22 proteinogenic amino acids, but cannot be used to quantitate tryptophan, which is destroyed during the acid hydrolysis step. Asparagine is determined as aspartic acid and glutamine as glutamic acid. The cystine and cysteine are converted to S-2-carboxyethylthiocysteine (CYSx) and the derivative is separated from the other amino acids. Citrulline which is present in some matrices and it is separated from other amino acids is not included in the method performance evaluation in the single laboratory validation (SLV). Method The proposed method met all the performance requirement limits set in standard method performance requirements (SMPR) 2014.013 for total proteinogenic amino acids and taurine. The correlation coefficient of multi-point calibration was not less than 0.999 for any amino acids at any point in the SLV study confirming the validity of linear dynanic range (LDR) and linearity of the method. The individual amino acids in the chromatogram were identified by absolute retention time and relative retention time (RRT) with respect to the internal standard norvaline. There were no significant (S/N Ratio <10) interferences from the reagents or by-products of derivatisation and targeted matrices. The method demonstrated high selectivity. Result Accuracy of the method was validated using standard reference materials (NIST SRM 1869 and 1849a) and spike recovery studies. The amino acid results in the SRMs were within the ranges of Reference Mass Fraction Values. The accuracy of the method was corroboratively validated by spike recovery studies. The average spike recovery range between 93 to 107% ensure the accuracy of the method for amino acids and compliance to the AOAC SMPR 2014.013. Conclusions Precision data of the method demonstrate that it meets the stakeholder requirements as per the SMPR. The mean RSDr for all the amino acids for 17 matrices selected for the SLV were not more than 4%. The method is very sensitive and the LOQ can go down to approximately ten times lower than the SMPR requirements. The sensitivity of method is a direct reflection of its signal to noise ratio which ensures guaranteed method performance at the lower levels of amino acids in these matrices. Highlights Taurine (aminoethane sulfonic acid) unlike the other amino acids is a beta-sulfonic amino acid that is not used in protein synthesis but is found as a free amino acid in tissues. The acidic functional group (-COOH) in common amino acid is replaced with a sulfonic acid (-SO3H) group in Taurine. The method offers baseline separation of citrulline which is an alpha amino acid generally present in Infant Formula and Adult/Pediatric Nutritional products. The separation of citrulline eliminates the risk of interference of this compound with other amino acids. The method can also separate and quantitate hydroxyproline, an important component of collagen that is often used to quantitate collagen. The method is simple and does not include any proprietary chemicals or instruments and can be performed on any basic reverse phase UHPLC system with UV detection.

scholarly journals Simultaneous Determination of Free Carnitine and Total Choline by Liquid Chromatography/Mass Spectrometry in Infant Formula and Health-Care Products: Single-Laboratory Validation

2008 ◽  
Vol 91 (4) ◽  
pp. 777-785 ◽  
Author(s):  
Pierre Andrieux ◽  
Tamara Kilinc ◽  
Christian Perrin ◽  
Esther Campos-Giménez
Keyword(s):  
Health Care ◽  
Standard Deviation ◽  
Simultaneous Determination ◽  
Relative Standard Deviation ◽  
Infant Formula ◽  
Free Carnitine ◽  
Official Method ◽  
Relative Standard ◽  
Single Laboratory

Abstract A single-laboratory validation study was conducted for a liquid chromatographic/mass spectrometric (LC/MS) method for the simultaneous determination of the free carnitine and total choline in milk-based infant formula and health-care products. The sample preparation used for both carnitine and choline was adapted from AOAC Official Method 999.14, with an acidic and enzymatic hydrolysis of esterified forms of choline. Carnitine and choline were quantified by ion-pair chromatography with single-quadrupole MS detection, using their respective deuterated internal standards. The repeatability relative standard deviation was 2.5 and 2.1, respectively, for carnitine and choline. The intermediate reproducibility relative standard deviation was <4.7 and 2.4, respectively, for carnitine and choline. The ranges of the average product-specific recoveries were 9298 and 94103, respectively, for carnitine and choline. Choline concentration determined in infant formula reference material SRM 1846 was in agreement with the reference value. The proposed method was compared with the enzymatic methods for a range of products; good correlation (r = 0.99) was obtained, although a significant bias was observed for both analytes. The method, with a short chromatographic run time (7 min), is convenient for routine analysis to enhance analytical throughput and is a good alternative to enzymatic assays.

Determination of Quaternary Ammonium Compounds in Oranges and Cucumbers Using QuEChERS Extraction and Ultra-Performance Liquid Chromatography/Tandem Mass Spectrometry

2014 ◽  
Vol 97 (4) ◽  
pp. 1021-1026 ◽  
Author(s):  
Francisco Javier Arrebola-Liébanas ◽  
María Angeles Herrera Abdo ◽  
José Luis Fernandez Moreno ◽  
José L Martínez-Vidal ◽  
Antonia Garrido Frenich
Keyword(s):  
Quaternary Ammonium ◽  
Ultra Performance Liquid Chromatography ◽  
Quaternary Ammonium Compounds ◽  
Fast Method ◽  
Benzethonium Chloride ◽  
Liquid Chromatography Tandem Mass ◽  
Didecyldimethylammonium Chloride ◽  
Accredited Laboratory ◽  
Ammonium Compounds

Abstract A simple and fast method has been developed for determining relevant quaternary ammonium compounds in cucumber and orange samples. The target compounds were benzoalkonium chloride (BAC-10, BAC-12, BAC-14, and BAC-16), didecyldimethylammonium chloride, and benzethonium chloride, all frequently used biocides in the agrifood industry. An extraction based on the buffered Quick, Easy, Cheap, Effective, Rugged, and Safe method and determination by ultra-performance LC/MS/MS that eluted the biocides in less than 5 min were used. The method was fully validated and implemented in a UNE-EN-ISO/IEC 17025 accredited laboratory for its application to the analysis of real samples. Performance characteristics of the method are reported, including an estimation of measurement uncertainty. Calibration curves were set between 0.01 and 0.150 mg/kg, LOD values were always between 0.4 and 1.0 μg/kg, LOQ values were in the range 1–4 μg/kg, recovery was between 81 and 115%, intraday and interday precision were always lower than 17% (expressed as RSD), and expanded uncertainty was always lower than 40%. The validation was accomplished for the two studied matrixes at spiking concentrations of 0.011 and 0.050 mg/kg. The method has been applied to the analysis of 30 cucumber and orange samples that were found to contain concentrations of BAC-12 that ranged between 0.015 and 0.210 mg/kg and of BAC-14 between 0.018 and 0.081 mg/kg.

Phenylboronic Acid Solid Phase Extraction Cleanup and Isotope Dilution Liquid Chromatography-Tandem Mass Spectrometry for the Determination of Florfenicol Amine in Fish Muscles

2015 ◽  
Vol 98 (3) ◽  
pp. 566-574 ◽  
Author(s):  
Della Wai-Mei Sin ◽  
Clare Ho ◽  
Yiu-Tung Wong
Keyword(s):  
Isotope Dilution ◽  
Solid Phase ◽  
Phenylboronic Acid ◽  
Accurate Determination ◽  
Internal Standard ◽  
Fish Muscles ◽  
Liquid Chromatography Tandem Mass ◽  
Cleanup Procedure ◽  
Acid Catalyzed

Abstract Florfenicol (FFC) residues in foods are regulated as the sum of florfenicol and its metabolites measured as florfenicol amine (FFA). An isotope dilution LC-MS/MS method utilizing phenylboronic acid (PBA) SPE cleanup is established for the accurate determination of FFA in fish muscles (i.e., salmon and tilapia) after acid catalyzed hydrolysis. Comparisons of the PBA SPE cleanup procedure with other cleanup procedures such as mixed-mode cationic (MCX) SPE and solid supported liquid–liquid extraction were performed. Quantification of FFA in fish muscles was accomplished by using matrix-matched calibration with FFA-D3 as the internal standard. The method was validated with FFA fortified fish muscles at three different levels (50, 100, and 200 μg/kg). Conversion of FFC to FFA by acid catalyzed hydrolysis was evaluated and found to be ≥88%. The recoveries of FFA in fish muscles at the three fortification levels ranged from 89 to 106%, and RSDs were ≤9% in all cases. The LOD values in salmon and tilapia muscles were 0.13 and 1.64 μg/kg, respectively. The LOQ values in salmon and tilapia muscles were 0.29 and 4.13 μg/kg, respectively. This method is suitable for the application in routine control of FFC in fishes according to its residue definition.

Sign in / Sign up

Export Citation Format

Share Document