Page 76 - Application Notebook - Solution for Food Safety

LAAN-A-LM-E111

Application Liquid Chromatography Mass Spectrometry

News Ultra-Sensitive and Rapid Assay of Neonicotinoids,

Fipronil and Some Metabolites in Honey by
No.C140 UHPLC-MS/MS [LCMS-8060]

Neonicotinoids are a class of insecticides widely used to After incubation at room temperature for one hour
protect fields as well as fruits and vegetables. with gentle shaking, a commercially available salt mix
Recently the use of these compounds became very from Biotage (4 g MgSO4, 1 g Sodium Citrate, 0.5 g
controversial as they were pointed as one cause of the Sodium Citrate sesquihydrate, 1g NaCl) was added.
honeybees colony collapse disorder. Since pollination is After manual shaking, samples were centrifuged at
essential for agriculture, extensive studies have been 3000 g for 5 minutes at 10 ºC.
conducted to evaluate the impact of neonicotinoids on Supernatant (6 mL) was transferred into a 15 mL
bee health. Following this the European Food Security tube containing 1200 mg of MgSO4, 400 mg PSA
Authoritiy (EFSA) limited the use of thiamethoxam, and 400 mg C18 from Biotage. After centrifugation
clothianidin and imidacloprid. Fipronil, a pesticide from at 3000 g and 10 ºC for 5 minutes the supernatant
a different chemical class, has been also banned by was transferred into a LCMS certified inert glass vial
EFSA for maize seed treatment due to its high risk for for analysis (Shimadzu LabTotal 227-34001-01).
honeybee health.
In order to better understand the effect of these Q Recovery
compounds on bees and their contamination in pollen An “all-flowers” honey from the local supermarket
and honey, a highly sensitive assay method was was extracted with or without spike at 50 ppt. A blank
necessary. A method was set up using Nexera X2 with extract (no honey) was prepared to evaluate losses or
LCMS-8060. non specific interactions. Results are presented in
Table 1.
Q Sample Preparation Calculated recoveries are within acceptance values 70-
Thiamethoxam-d3, imidacloprid-d4 and chlothianidin-d3 120 % from EU SANTE/11945/2015.
were used as internal standards.
Compound extraction was performed using a QuEChERS Table 1 Measured Recoveries in Honey
(Quick, Easy, Cheap, Effective, Rugged and Safe) method Compound Recovery Compound Recovery
with an additional dispersive Solid Phase Extraction Acetamiprid 78.8 % Fipronil sulfone 74.2 %
(dSPE) step. Acetamiprid-N-desmethyl 93.4 % Imidaclorpid 83.2 %
5 g of honey (±1 %) were weighted in a 50 mL Chlothianidin 70.6 % Nitenpyram 87.0 %
polypropylene tube. 5 μL of internal standard solution at Dinotefuran 76.5 % Thiacloprid 82.2 %
5 μg/mL of each compound in acetonitrile was added on Fipronil 78.1 % Thiamethoxam 75.6 %
honey and let dry for 10 minutes. 10 mL of ultra pure
water were added and the samples were homogenized
by vortex mixing for 1 minute. 10 mL of acetonitrile were
then added followed by vortex mixing for 1 minute.

Acetamiprid Acetamiprid-N-desmethyl Chlothianidin Dinotefuran Fipronil
Q 223.10 > 126.00 3.86e3 Q 209.05 > 126.05 3.31e3 Q 250.10 > 169.10 3.93e3 Q 203.00 > 114.10 1.78e3 Q 435.00 > 330.00 2.31e3
100.00 100.00 100.00 73.21 100.00

% % % % %

0.00 0.00 0.00 0.00 0.00
2.10 2.15 2.20 2.25 2.30 2.35 2.40 2.45 2.10 2.15 2.20 2.25 2.30 2.35 2.40 2.45 2.00 2.05 2.10 2.15 2.20 2.25 2.30 2.35 1.50 1.55 1.60 1.65 1.70 1.75 1.80 1.85 3.00 3.05 3.10 3.15 3.20 3.25 3.30 3.35
Fipronil sulfone Imidacloprid Nitenpyram Thiacloprid Thiamethoxam
Q 451.00 > 282.00 4.01e3 Q 256.10 > 175.10 6.43e3 Q 271.00 > 126.00 2.33e3 Q 253.10 > 126.00 6.00e3 Q 292.10 > 211.10 4.07e3
100.00 100.00 100.00 100.00 100.00

% % % % %

0.00 0.00 0.00 0.00 0.00
3.05 3.10 3.15 3.20 3.25 3.30 3.35 3.40 2.00 2.05 2.10 2.15 2.20 2.25 2.30 1.55 1.60 1.65 1.70 1.75 1.80 1.85 1.90 2.25 2.30 2.35 2.40 2.45 2.50 2.55 1.80 1.85 1.90 1.95 2.00 2.05 2.10
Fig. 1 Chromatogram of the Target Compounds at Their Lower Limit of Quantification