Page 64 - Application Notebook - Solution for Food Safety

LAAN-A-LC-E285

Application High Performance Liquid Chromatography

News Analysis of Residual Antimicrobials in Meat with

Antimicrobial Screening System (Part 1)
No.L509

In May 2006, the positive list system took effect in Japan Q Sample Pretreatment
that, in principle, prohibited the sale of food products Sample pretreatment was performed based on
with residual levels of pesticides, animal feed additives, Simultaneous Analysis Method ᶗ for Veterinary Drugs by
and veterinary drugs (collectively referred to as HPLC (Livestock and Marine Products). 2),3) After
agricultural chemicals, etc.) above the level determined
by the Minister of Health, Labour and Welfare. 1) acetonitrile extraction and removing fat by acetonitrile/
Antimicrobials are a type of veterinary drug and animal hexane partitioning, sample solution was prepared by
feed additive, and used for the treatment and prevention evaporation then redissolution. Fig. 1 shows the sample
of disease in livestock and marine products. Quinolones pretreatment protocol, and Table 1 shows sample
and sulfonamides are two common groups of synthetic solution concentrations after pretreatment. Refer to the
antimicrobials. instruction manual of the system for the details of the
Shimadzu's quick and simple antimicrobial screening sample pretreatment procedure.
system is capable of screening 24 antimicrobials
compounds. An example screening analysis targeting 12
widely used quinolones (old quinolones, new quinolones) Sample (homogenized) 1 g
is described here. Application News No.L510 also Extraction
describes an example screening analysis targeting 12
antimicrobials including sulfonamides (also including Supernatant
antifolates).
Hexane Partitioning
Q Antimicrobial Screening System
Fat Removal
Shimadzu's antimicrobial screening system is able to
determine whether levels of antimicrobials subject to
regulation in various countries are above a maximum Acetonitrile Layer Hexane Layer
residue limit (MRL). Table 1 shows MRLs for the target
quinolones. Evaporation
The system uses an i-Series integrated HPLC instrument Residue
and RF-20Axs high-sensitivity fluorescence detector,
and comes with a sample pretreatment method, Redissolution
analytical column, analytical method files, and a UV
spectral library that allow for immediate operation after Acetonitrile Layer - Aqueous Layer
installation. When the analysis method capable of
simultaneous component analysis is used, the system HPLC
can be used for simultaneous screening of multiple
components. The determination of whether MRL have Fig. 1 Sample Pretreatment Protocol
been exceeded can be viewed immediately after the
system completes analysis. The photodiode array (PDA) Table 2 Analytical Conditions
detector built into the i-Series instrument supports
highly accurate screening with compound identification System : LC-2040C 3D, RF-20AXS
based on retention times as well as UV spectra. Column : Shim-pack FC-ODS (150 mm L. × 4.6 mm I.D., 3 μm)
Mobile Phase : A) 20 mM (Sodium) Phosphate Buffer Containing
0.1 M Sodium Perchlorate
Table 1 Maximum Residue Limits and Sample Solution B) Acetonitrile/Methanol=90/10
Concentration of Screening Target Compounds Time Program : Gradient Elution
Flowrate : 1.0 mL/min
MRL Sample Solution Column Temp. : 40 ˚C
Compound
(mg/kg) Concentration (mg/L) Injection Volume : 5 μL
1 Marbofloxacin 0.01 0.025 Detection : <LC-2040C 3D>
2 Ofloxacin 0.01 0.025 280 nm
3 Ciprofloxacin 0.01 0.025 <RF-20AXS>
Ex at 290 nm, Em at 495 nm
4 Danofloxacin 0.01 0.025 Ex at 325 nm, Em at 365 nm
5 Enrofloxacin 0.01 0.025
Cell Temp. : 40 ˚C (PDA), 30 ˚C (RF)
6 Orbifloxacin 0.01 0.025
7 Sarafloxacin 0.01 0.025
8 Difloxacin 0.01 0.025
9 Oxolinic acid 0.01 0.025
10 Nalidixic acid 0.01 0.025
11 Flumequine 0.01 0.025
12 Piromidic acid 0.01 0.025