LC/MS/MS Analysis of Neonicotinoid Pesticides in Dandelion Blossoms on Ascentis® Express C18 after Dispersive SPE (QuEChERS) using Supel QuE

LC/MS/MS Analysis of Neonicotinoid Pesticides in Dandelion Blossoms on Ascentis® Express C18 after Dispersive SPE (QuEChERS) using Supel™ QuE application for HPLC


analytical column

Product No.

Ascentis® Express C18, 2.7 μm HPLC Column

2.7 μm particle size, L × I.D. 10 cm × 3 mm

SPE tube or plate

Product No.

Supel QuE

Acetate Tube, pk of 50, AOAC® 2007.01

Supel QuE

Empty Centrifuge Tube with Lid, centrifuge tube volume 50 mL, pk of 50, suitable for EN 15662:2008 per BS


Product No.


PESTANAL®, analytical standard


sample preparation

Dispersive (QuEChERS)


3 g pulverized dandelion blossoms, homogenized in 10 mL water

extraction tube

Supel QuE Acetate extration tube (55234-U)

extraction process

add 25 mL of acetonitrile; add contents of Supel QuE acetate extraction tube; shake immediately for 1 minute; centrifuge at 3400 rpm for 5 minutes

clean-up tube

Supel QuE PSA/C18 tube (55288-U)

clean-up process

Transfer 1 mL of the acetonitrile layer into a Supel QuE PSA/C18 cleanup tube; shake for 1 minute; centrifuge at 3500 rpm for 3 minutes; (draw off 700 uL of supernatant, evaporate to dryness at 50 °C under nitrogen; reconstitute in 200 μL of 50:50 0.1% formic acid:0.1% formic acid in methanol)


Ascentis Express C18, 10 cm x 3.0 mm I.D., 2.7 μm particles (53814-U)

mobile phase

[A] 0.1% formic acid in water; [B] 0.1% formic acid in methanol


30% B from 0 to 5 min; to 100% B in 0.2 min; held at 100% B for 5.3 min; to 30% B in 0.5 min; held at 30% B for 5 min

flow rate

500 μL/min


3800 psi (262 bar)

column temp.

25 °C


MS, ESI(+), MRM, m/z 203.2/129.2, 271.2/225.0, 292.1/211.0, 256.0/175.2, 250.0/132.0, 223.2/126.0, 253.0/125.8


3 μL


Analysis Note

The advent of the die-off of honey bees due to colony collapse disorder (CCD) has spawned investigation into pesticide exposure as the cause. Neonicotinoids are among the suspected culprits. In this application, the QuEChERS approach using Supel QuE was used for extraction and cleanup prior to analysis of seven neonicotinoid pesticides in flower blossoms. Ascentis® Express C18 was chosen due to the high efficiency associated with its Fused-Core® particle, and its relatively low backpressure as compared to sub-2 micron UHPLC columns. This allowed the column to be used in a standard pressure HPLC system with a relatively high concentration of aqueous at the start of the mobile phase gradient.

Legal Information

Ascentis is a registered trademark of Merck KGaA, Darmstadt, Germany
Fused-Core is a registered trademark of Advanced Materials Technology, Inc.
Supel is a trademark of Sigma-Aldrich Co. LLC