ISO 16186 pdf free download
ISO 16186-2021 pdf free download.Footwear一Critical substances potentially present in footwear and footwear components一 Determination of dimethyl fumarate (DMFU).
6.6 Volumetric flasks
6.7 Gas chromatograph with mass selective detector (GC-MS or GC-MS/MS).
6.8 Amber glass vial, with screw cap that can be tightly sealed (e.g. volume of 10 ml).
6.9 Activated magnesium silicate cartridge.
NOTE The two following cartridges have been found suitable.
a) Pre-packed cartridge of FL-PR FIorisil®2) (170 pm. 80 A) 2 g/12 ml.
b) Bulk material ofFlorisil® 100-200 mesh, fine powder.
6.10 Nitrogen evaporator, with conical tubes and with adjustable temperature, suitable for operation up to 40 °C.
7 Sampling
The test specimen shall consist of a single material type (made of textile, leather, polymer or other organic material), which is tested separately.
Cut the homogenous material samples into pieces ofabout 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, taking into consideration the limits ofdetection and quantification.
NOTE 2 Desiccant can be a source of DMFU contamination of the footwear. Desiccant samples can be used without any processing.
8 Procedure
8.1 Standard procedure
Weigh (1,0 ± 0,1) g ofthe sample in a glass vial (62), record the mass to the nearest 1 mg, add 0,1 ml of the solution of internal standard working solution (5.6.2) and 9.9 ml of acetone (M). and seal the vial. Extract the sample at (60 ± 5) °C for (60 ± 5) mm in an ultrasonic bath (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 a gentle stream of nitrogen (6.10).
Filter this solution through a PTFE membrane filter (&4).
Transfer an aliquot of the extract to a GC vial () 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 (&Z), record the mass to the nearest 1 mg, add 0,1 ml of the solution of internal standard (5.6.2) and 9,9 ml of acetone (&1). and seal the vial. Extract the sample at (60 ± 5) °C for (60 ± 5) mm in an ultrasonic bath (fh3).
2) Florisil is a registerd trademark of U.S. Silica Company. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of the product named. Equivalent products may be used If they can be shown to lead to the same results.
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 () 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 (M) and transfer it to a GC-MS vial ().
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 (5A), 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 &Z).
An example of calibration measurement is given in Clause A.2
8.4 Determination of dimethyl fumarate
Determine the DMFU extracted in thi or 2 by GC-MS or GC-MS/MS (61).
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.
9 Expression of results
9.1 Calculation of dimethyl fumarate in the sample
Plot a calibration graph of the response against the known standard concentration (corrected for the response for the internal standard). From the calibration graph, interpolate the concentration of the dimethyl fumarate in mg/I (p1).ISO 16186 pdf download.