SN/T 1594-2019 PDF English
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| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivery | Name of Chinese Standard | Status |
| SN/T 1594-2019 | English | 280 |
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Determination of buprofezin residue in tea and herbal tea for export
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| SN/T 1594-2005 | English | 519 |
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Inspection of buprofezin residue in tea for import and export. Gas chromatographic method
| Obsolete |
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SN/T 1594-2019: Determination of buprofezin residue in tea and herbal tea for export---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/SNT1594-2019
Determination of buprofezin residue in tea and herbal tea for export
Foreword
This standard was drafted in accordance with the GB/T 1.1— 2009.
This standard is the revision of SN/T 1594— 2005《Inspection of buprofezin residue in tea for import and
export-Gas chromatographic method》.
The differences between this standard and SN/T 1594-2005 are as follows :
— Changed the name of standard ；
— Extended the scope ；
— Amended the pretreatment and instrument condition of GC method ；
— Added LC-MS/MS method.
Please pay attention that some contents in this standard may refer to patents. The institution doesn’t take
on the responsibility to identify these patents.
This standard is proposed by and is under the charge of General Administration of Customs of the People’s
Republic of China.
This standard was drafted by Hangzhou Customs District of the People’s Republic of China.
The main drafters of this standard are Zhu Xiaoyu, Huang Chaoqun, Cui Xiaomei, Lou Chengjie, Wu
Juan, Chen Li, Jiang Qinting, Fang Qun.
This standard replaces the standard previous published as :
— SN/T 1594— 2005.
Determination of buprofezin residue in tea and herbal tea for export
1 Scope
This standard specifies the determination of buprofezin residue in tea and herbal tea by liquid chromatography-
tandem mass spectrum and gas chromatography.
This standard is applicable to the determination of buprofezin in green tea, black tea, pu’er tea, oolong
tea, burdock tea, chrysanthemum tea, eucommiae tea and barley tea for export.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute
provisions of this standard. For dated references, subsequent amendments to, or revisions of any of
these publications do not apply. However parties to agreements based on this standard are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below.
For undated references, the latest edition of the normative document referred to applies.
GB/T 6682 Water for analytical laboratory use— specification and test methods
Method Ⅰ LC-MS/MS Method
3 Principle
The test samples are extracted with water-acetone. The extract is partitioned with hexane, cleaned up
by florisil solid phase and detected by liquid chromatography-tandem mass spectrometry using external
standard method.
4 Reagents and materials
Unless otherwise specified, all the reagents used should be chromatographic pure, “water” is distilled
water.
4.1 Acetone.
4.2 Hexane.
4.3 Diethyl ether.
4.4 Methanol.
4.5 Sodium chloride : analytical grade.
4.6 Ammonium acetate.
4.7 Formic acid.
4.8 Hexane-diethyl ether (6+4, V/V): Volume 600 mL hexane, then add 400 mL diethyl ether, mix them.
4.9 Ammonium acetate-formic acid mixed solution : Accurately weigh 0.38 g, of ammonium acetate,
dissolved with water, then added 1.0 mL of formic acid and diluted to 1000 mL with water.
4.10 Standard : Buprofezin, C16H23N3OS, CAS NO.69327-76-0, Purity ≥ 99.0%.
4.11 Standard stock solution : Accurately weigh appropriate standard(4.10), dissolved with methanol,
the concentration of solution is 200 μg/mL. Stored under 0~4 ℃ and stable for 6 months.
4.12 Standard intermediate solution : Accurately transfer 0.50 mL of standard stock solution, diluted
to 10 mL with methanol. The concentration of solution is 10 μg/mL. Then accurately transfer 1.0 mL of this
solution, diluted to 10 mL with methanol. The concentration of standard intermediate solution is 1.0 μg/mL.
4.13 Standard work solution : Accurately transfer 1.0 mL of standard intermediate solution, diluted to 50
mL with methanol. The concentration of standard work solution is 20 ng/mL. Accurately transfer 0.25 mL,
0.50 mL, 1.0 mL, 2.5 mL and 5.0 mL of the solution which concentration is 20 ng/mL, diluted to 10 mL
with methanol. The concentrations of standard work solutions are 0.50 ng/mL, 1.0 ng/mL, 2.0 ng/mL, 5.0
ng/mL and 10 ng/mL. Stored under 0℃ ~4 ℃ and stable for 3 months.
4.14 Florisil SPE column : 1 g, preconditioned with 5 mL of hexane before use.
4.15 Millipore filter : ≤ 0.45 μm , organic phase.
5 Apparatus and equipment
5.1 Liquid chromatography tandem mass spectrometry, equipped with ESI.
5.2 Electronic balance : accurate to 0.000 1 g and 0.01 g.
5.3 Vortex mixer.
5.4 Homogenizer.
5.5 Centrifuge(4 000 r/min).
5.6 Rotary vacuum evaporator.
5.7 Solid Phase Extraction System.
6 Preparation and storage of test sample
6.1 Preparation of test sample
Take approximately 500 g of representative sample, smashed thoroughly by a chopper, passed through a 2.0
mm sieve, and put into clean containers, which is sealed and labeled.
6.2 Storage of test sample
Test samples should be stored at room temperature. In course of sampling and sample preparation, attention
must be taken to avoid contamination or any factors which may cause the change of residue content.
7 Procedure
7.1 Extraction
Weigh 2 g (accurate to 0.01 g) of the test sample into a 50 mL polypropylene tube, 10 mL of water was
added. The sampled was soaked for 2 h. Then 20 mL of acetone was added. After homogenized for 2
minutes, 4 g sodium chloride and 15 mL of hexane were added. the sample was mixed for 1 minute and
centrifuged at 4 000 r/min for 5 minutes. The upper solution was transferred into a concentrate bottle, the
residual was extracted with 15 mL of hexane again, the solution was transferred into the same concentrate
bottle and condensed to nearly dry, waiting for cleaning-up.
7.2 Cleaning-up
Add 10 mL of hexane to dissolve the residual. 1.0 mL of the solution was transfered to a florisil column
(4.14) . After sample loading, buprofezin was eluted by 10 mL of hexane-diethyl ether (4.8). The eluate
was evaporated and redissolved with 2.0 mL of methanol for determination by LC-MS/MS.
7.3 Determination
7.3.1 LC-MS/MS operating condition
LC-MS/MS operating condition is as follows :
a)Column : C18, 100 mm ×2.1 mm (i.d), 3.5 μm, or the equivalent ；
b)Mobile phase : Ammonium acetate-formic acid mixed solution and methanol, for gradient elute
condition, see Table 1 ；
......
Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al.
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