INTRODUCTION

The method is used for the determination of the mass fraction of methionine hydroxy analogue (DL-2-hydroxy-4-(methylthio)butyric acid (HMTBa) and its calcium salt) in fodder additives by capillary electrophoresis.

Currently, fodder additives containing HMTBa or its calcium salt, are presented on the market under such  brand names as MHA®, Alimet®, Rhodimet®, and others.

For the determination of free methionine in fodder additives use the method М 04-63-2016  (Lumex  Instruments set, order No 0300002780).

MEASUREMENT METHOD

The measurement method is based on capillary zone electrophoresis with direct UV detection at the wavelength of 200 nm.

MEASUREMENT RANGE

The measurement range for HMTBa is 60–100%. If necessary, a result of analysis may be expressed as methionine or calcium salt of HMTBa.

ADVANTAGES OF CE METHOD

CE method for the determination of HMTBa has a lot of advantages compared with other analytical methods used for this purpose, such as HPLC, potentiometry, complexometry:

· The HPLC column is not required, so the cost of the analysis drops dramatically compared with HPLC.

· Direct determination of the main analyte (HMTBa) in contrast to the indirect determination of  calcium (complexometry) and/ or total organic sulfur (potentiometry) content.

· Analysis time using CAPEL CE system is less than 5 minutes.