ISO 16186-2021 pdf free download – Footwear — Critical substances potentially present in footwear and footwear components — Determination of dimethyl fumarate (DMFU).
6.8Amber glass vial, with screw cap that can be tightly sealed (e.g.volume of 10 ml).
6.9Activated magnesium silicate cartridge.
NOTE The two following cartridges have been found suitable.a)Pre-packed cartridge of FL-PR FlorisilR2) (170 um,80 A) 2 g/12 ml.b)Bulk material of FlorisilR 100-200 mesh, fine powder.
6.10 Nitrogen evaporator, with conical tubes and with adjustable temperature, suitable for operationup to 40°C.
7 Sampling
The test specimen shall consist of a single material type (made of textile, leather, polymer or otherorganic material), which is tested separately.
Cut the homogenous material samples into pieces of about 3 mm to 5 mm edge length.
NOTE 1 Up to three test specimens (of equal mass) of the same material type can be tested together,takinginto consideration the limits of detection and quantification.
NOTE2 Desiccant can be a source of DMFU contamination of the footwear. Desiccant samples can be usedwithout any processing.
8Procedure
8.1Standard procedure
Weigh (1,0±0,1) g of the sample in a glass vial (6.2), record the mass to the nearest 1 mg, add 0,1 ml ofthe solution of internal standard working solution (5.6.2) and 9,9 ml of acetone (5.1), and seal the vial.Extract the sample at (60 ±5) °C for (60主5) min in an ultrasonic bath(6.3).
WARNING – Do not open the vial before cooling as the content can be under pressure.
After cooling to below at least 27 C, decant the solution and, if necessary, reduce to 1,0 ml under agentle stream of nitrogen (6.10).
Filter this solution through a PTFE membrane filter (6.4).
Transfer an aliquot of the extract to a GC vial (6.5) and seal with a cap.8.2 Procedure for complex matrix
8.2.1 Extraction
Weigh(1,0±0,1) g of the sample in a glass vial (6.2), record the mass to the nearest 1 mg, add 0,1 ml ofthe solution of internal standard (5.6.2) and 9,9 ml of acetone (5.1), and seal the vial.Extract the sampleat (60± 5)C for (60 ± 5) min in an ultrasonic bath(6.3).
8.2.2 Clean-up
After cooling to below at least 27 °C, transfer 5 ml of the extract to a conical tube and reduce to around 0,2 ml under a gentle stream of nitrogen (6.10).
Reconstitute the extract to 1 ml with n-Hexane (5.2).
Purify the reconstituted extract on an activated magnesium silicate cartridge (6.9) by the following procedure.
a) Conditioning with 6 ml of n-hexane/acetone, with a volume fraction of 80/20.
b) Decant 1 ml of the reconstituted extract on the SPE cartridge.
c) Elute with 4 ml of n-hexane/acetone, with a volume fraction of 80/20 (V/V).
d) Collected the eluent in a 5 ml volumetric flask, fill up to the mark with acetone.
e) Filter the solution through a PTFE membrane filter (6.4) and transfer it to a GC-MS vial (6.5).
8.3 Preparation of calibration solutions Prepare at least 3 calibration solutions of a mixture of dimethyl fumarate and dimethyl maleate, including internal standard, from the working solutions (5.6.4 and 5.6.2), in acetone (5.4), at suitable concentrations for the analysis. Each solution shall contain the internal standard in a concentration that matches the internal standard concentration in the final sample extract (i.e. taking into account any volume reduction in 8.2). An example of calibration measurement is given in Clause A.2 8.4 Determination of dimethyl fumarate Determine the DMFU extracted in 8.1 or 8.2 by GC-MS or GC-MS/MS (6.7). Sufficient separation of the dimethyl fumarate and dimethyl maleate is required in order to avoid false- positive results caused by dimethyl maleate. Examples of chromatographic conditions are given in Annexes A and B.ISO 16186 pdf download.