Analysis of Aflatoxin B1, B2, G1, and G2 in Corn Meal, Wheat Meal, and Raw Peanut Paste Matrices

The Supel™ Tox AflaZea SPE cartridge was used to demonstrate the cleanup of corn meal, wheat meal, and raw peanut paste matrices prior to the analysis of Aflatoxin B1, B2, G1, and G2. In the procedure, corn meal, wheat meal, and raw peanut paste extracts were spiked with Aflatoxin Standard Mix (Product No. 34036) and run through the Supel Tox AflaZea SPE cartridges. The eluate was collected and diluted for HPLC analysis.

Results from cleanup using Supel Tox AflaZea SPE cartridges

Figure 1. Results From Cleanup using Supel Tox AflaZea SPE Cartridges

HPLC Conditions
column:
Ascentis® Express C18, 10 cm x 2.1 mm I.D., 2.7 µm (Product No. 53823-U); mobile phase: (A) water, (B) acetonitrile, (C) methanol (700:120:120,A:B:C) with 0.780 g potassium bromide and 230 µL nitric acid; flow rate: 0.400 mL/min; column temp.: 35 °C; detector: Fluorescence detector; Excitation: 360 nm; Emission: 440 nm
injection: 40 µL


Results illustrate that Supel Tox AflaZea SPE cartridges provide exceptional cleanup of corn meal, wheat meal, and raw peanut paste samples, yielding high analyte recoveries and low %RSD for aflatoxin analysis.

Analyte Recovery and %RSD of Aflatoxins from Corn, Wheat, and Peanut Paste (n = 3)

Figure 2. Analyte Recovery and %RSD of Aflatoxins from Corn, Wheat, and Peanut Paste (n = 3)


In the “bind and elute” strategy, the analyte of interest becomes bound to the SPE sorbent. The unwanted matrix is removed, and the analyte is ultimately eluted. In “interference removal,” the unwanted matrix components remain bound to the sorbent, while the purified analylte is eluted. This strategy reduces the number of purification steps, allowing for time savings and increase in sample throughput. The Supel Tox AflaZea, DON, and Tricho SPE cartridges employ the “interference removal” strategy.

Comparison of "Bind and Elute" and "Interference" Principles

Figure 3. Comparison of "Bind and Elute" and "Interference" Principles


Comparison of Supel Tox SPE Cartridges to Immunoaffinity Columns for Matrix Removal Prior to Mycotoxin Analysis

  • Ten times faster = Ten times sample throughput
  • Vast improvement in reproducibility

An experiment comparing the use of the Supel Tox AflaZea SPE cartridge to a leading immunoaffintiy column for the analysis of Aflatoxins B1, B2, G1, and G2 in peanut paste, illustrates that the Supel Tox AflaZea SPE cartridge is superior to the immunoaffinity purification methods in terms of process simplicity, time required for sample preparation, and control of variation.

Table 1. Procedure for Analysis of Aflatoxin (n = 3) using Immunoafinity vs. Supel Tox

  Immunoaffinity Supel Tox AflaZea SPE Cartridge
Sample Prep Time
(post-extraction to pre-analysis)
  • 60 minutes
  • 8 samples/day (if processing 1 at a time)
  • 6 minutes
  • 80 samples/day (if processing 1 at a time)
Ease of Use
  • Large volumes of liquid
  • Controlled drop rates
  • Numerous complicated steps
  • Additional buffer salts required
  • Must be refrigerated, brought to room temp before use
  • Small volumes of liquid
  • Vacuum filtration used
  • Steps few and not complicated
  • No additional reagents required
  • Column does not require special storage conditions
Procedure
(post-extraction to analysis)
Stage 1 (15 minutes)
  1. Configure manifold for waste collection
  2. Add 1 mL sample to 17 mL phosphate buffered saline, vortex
  3. Uncap/Mount/Drain Cartridges by gravity
  4. Apply Reservoirs, Load Sample onto Cartridges
Stage 2 (15 minutes)
  1. Rinse Interferences
  2. Reconfigure Manifold for Sample Collection
  3. Elute/Collect Sample
Stage 3 (30 minutes)
  1. Evaporate Sample to Dryness
  2. Reconstitute Sample and Vortex
  3. Transfer 0.2 mL Sample to Vial
  4. Dilute Sample and Vortex
Analysis
Purify and Transfer (6 minutes)
  1. Configure manifold for sample collection
  2. Mount Cartridges
  3. Load 2 mL sample
  4. Elute and Collect Under Vacuum
  5. Transfer 0.2 mL Sample to Vial
  6. Dilute Sample and Vortex
Analysis

 

Cleanup of Aflatoxins in Peanut Paste: Immunoaffinity Versus Supel™ Tox (n=3)

Figure 4. Cleanup of Aflatoxins in Peanut Paste: Immunoaffinity Versus Supel™ Tox (n=3)

Legal Information

Supel is a trademark of Sigma-Aldrich Co. LLC
Ascentis is a registered trademark of Sigma-Aldrich Co. LLC

Materials

     
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