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BLG ELISA KIT

β-lactoglobulin ELISA Kit is intended for quantitative determination of β-lactoglobulin (BLG) in raw as well as in thermally modified foods.

β-lactoglobulin ELISA Kit contains all required reagents for extraction and quantitative determination of β-lactoglobulin (BLG).

It is possible to determine up to 40 / 16 samples in duplicates (96 wells microtitre plate / 48 wells microtitre plate) with the set β-lactoglobulin ELISA Kit.

Time required for the sample preparation and extraction: 1 hour (10 samples)
Time required for ELISA determination: 2 hours and 30 minutes
Limit of detection (LOD): 0.07 ppm (mg/kg)
Limit of quantification (LOQ): 0.20 ppm (mg/kg)
Calibration scale range: 0.2 – 20 ppm (mg/kg)
Expiration time: 18 months (at 2 – 8 °C)

Milk is one of main allergenic foods, especially for children. Prevalence of this allergy differs in different countries; the incidence varies between 1 % and 3 %. Native milk and milk products contain protein allergens (see below) as there is no proof for the proposition that milk processing could change the protein structure to the extent of changing its allergenic properties. This is also the case with thermally processed milk. Cow’s milk contains 30 - 35 g proteins/litre. Its acidification to the pH value of 4.6 causes formation of 2 fractions – whey (20% content of proteins) and curd (80% content of proteins). The whey contains mainly beta-lactoglobulin (BLG), alpha-lactalbumine (ALA), bovine serum albumin (BSA), lactoferrin (LF) and immunoglobulins (Igs). The curd consists of casein (CAS) that occurs in 4 modifications – named Alpha s1, Alpha s2, Beta and Kappa.

The determination of BLG is based on its immunochemical reaction with a specific antibody. BLG present in calibrator, control sample or analysed sample – extract of the analysed foodstuff – reacts in the first step with a specific antibody coated on the walls of wells of a microtitre plate. After rinsing of unbound proteins follows the second incubation step during which the specific antibody conjugated with an enzyme (horse-radish peroxidase) reacts with the coated BLG. After incubation, the wells are rinsed and the conjugate bound in the wells is detected by the addition of a chromogenic substrate. The intensity of resulting colouration is proportional to the concentration of BLG in the calibrators and samples.