AOAC Final Action Methods in 2017

832 J OSEPH ET AL . : J OURNAL OF AOAC I NTERNATIONAL V OL . 101, N O . 3, 2018

An extensive campaign was carried out through AOAC INTERNATIONAL and ISO/International Dairy Federation meetings and other contacts to recruit potential laboratories for MLT. Formal invitations were sent to more than 30 laboratories around the world by the study director, and 15 laboratories agreed to participate. Delivery of SPIFAN matrixes to a laboratory in Thailand failed due to issues with the country ’ s import clearance requirements. Two laboratories could not progress with the MLT within the time frame due to inadequate resources or other commitments. The remaining 12 laboratories from 10 different countries who participated in the MLT study are listed in Table 1. The study was carried out using SPIFAN II matrixes, which represent most of the products in the scope of the project (infant formula and adult nutritionals made from any combination of milk, soy, rice, whey, hydrolyzed protein, starch, and amino acids, with and without intact protein). Fourteen different product types were provided to each laboratory, including two practice samples and 12 samples for MLT over 2 separate days. Two split samples of each matrix were included in the package as blind coded duplicates to analyze on the same day. The samples are summarized in Table 2. The homogeneity assessment of SPIFAN product matrixes was performed by analyzing several active nutritional ingredients. The testing was performed by Covance Laboratories Inc. (at one of their facilities). The homogeneity report was provided to the study director before commencing the MLT study. It confirmed that all powder samples were homogeneous. The participating laboratories were requested to analyze two practice samples in duplicate using the First Action method provided and to report the results to the study director. It was communicated to the laboratories that any deviation, such as the necessity to substitute reagents, analytical column, apparatus, or instruments, must be duly recorded and reported. Electronic templates were provided to the participants for data reporting, and raw data were requested when necessary. After the data review, the study director identified the laboratories that had the capability to run the analysis successfully. The study director also had discussions with the laboratories that produced unacceptable data to see whether there were any technical reasons that could be resolved within a reasonable time frame in order to include them in the second part of the study.

active in the human system. The chemical formula of biocytin is C 16 H 28 N 4 O 4 S, with a MW of 372.48. The naturally active forms of biotin in foodstuffs are d -biotin and d -biocytin, although the fortified form is exclusively d -biotin. These two forms, therefore, should be determined in order to estimate the total biotin nutritional value. Due to the absence of a standard analytical procedure for total biotin, the objective of SPIFAN is to establish an international consensus method for the determination of total biotin in infant formula and adult nutritionals that will meet the demand of the analytical community, benefit market supply, and assist in the resolution of a dispute. The AsureQuality Auckland Laboratory has developed a method that is specific, precise, accurate, and robust for the analysis of biotin and biocytin in infant formula and adult/ pediatric nutritional formulas (1 – 8). The method meets the Standard Method Performance Requirements (SMPRs SM ; 9, 10) and has an assured LOQ of 0.1 µg/100 g (1 ppb) based on a simple mathematical relationship between the lowest standard concentration and a dilution factor. The method involves IAC (R- Biopharm Rh ˆ one EASI-EXTRACT ® Biotin, or equivalent) cleanup and extraction, followed by LC – UV set at 200 nm. The laboratory has carried out an extensive single-laboratory validation (SLV) study (11) following SPIFAN SLV guidelines (12) using SPIFAN kit samples and NIST SRM 1849a. The SLV, along with the method, was reviewed by the AOAC Expert Review Panel in 2016 and approved as First Action Official Method 2016.02 (13). The objective of the MLT study was to establish method reproducibility between various laboratories to demonstrate the suitability of the method as an international reference method (14), with endorsement as an AOAC Final Action method and possible adoption in the future by the International Organization for Standardization (ISO) and Codex. The study was chaired by George Joseph from AsureQuality Ltd (Auckland, New Zealand) and monitored by the AOAC Official Methods Board through its delegated personnel. The study is divided into two parts: method setup and qualification of participants (part 1) and MLT by the qualified participants (part 2). Collaborative Study (MLT)

Downloaded from https://academic.oup.com/jaoac/article-abstract/101/3/831/5653969 by guest on 05 May 2020

Table 1. MLT participants

Lab No.

Laboratory name

Address

Country

1 2 3 4 5 6 7 8 9

Abbott Laboratories

3300 Stelzer Rd, Columbus, OH 43219 151 bis, Ave Jean Jaures, Pessac 33600

United States

Aquanal Laboratoire Aquitaine Analyses

France

AsureQuality New Zealand Ltd AsureQuality Singapore Pte. Ltd

131 Boundary Rd, Auckland 0600

New Zealand

29 Tai Seng Ave 534119

Singapore

DTS Food Laboratories

71 Boundary Rd, Melbourne VIC 3051

Australia

FirstSource Laboratory Solutions LLP

IDA, Nacharam Cross Rd, Hyderabad 500076

India

Fonterra Co-operative Group Ltd

Cnr No. 1 Rd and SH26, Waitoa 3341 3600 Eagle Nest Dr, Crete, IL 60417

New Zealand United States United Kingdom

M´erieux NutriSciences R-Biopharm Rh ˆ one Ltd Mead Johnson, China

45 Acre Rd, Glasgow G20 0XA

10 11 12

Xia Yuan Rd, Dongji ID, Guangzhou 510730

People ’ s Republic of China

Mead Johnson, The Netherlands

Middenkampweg 2, Nijmegen 6545CJ

The Netherlands

Nestl´e Research Centre, Switzerland

Case Postale 44, Lausanne 26, CH-1000

Switzerland