REAGEN™ BTS Combo Strip Test Kit is a qualitative and rapid lateral flow assay designed to detect beta-lactam, tetracycline, and sulfonamide antibiotic residues in raw commingled cow’s milk.This test uses a uses novel antibiotic binding proteins which are highly active in cold milk and eliminate the need for a heating block. This test is designed for rapid field use or reference lab settings. The unique features of the kit are:

§  Rapid strip test method –7 minutes

§  Works in cold milk

§  Novel binding proteins that requires no heating step

§  High sensitivity

§  High reproducibility

Procedure Overview

The assay uses a competitive colloidal gold based format. The milk sample (200 μL) is added to a clear plastic reaction vessel, and used to resuspend the lyophilized reagents to a uniform pink color in the bottom of the microtiter wells. The milk is incubated briefly (3 min) to allow the antibiotic binding proteins on the gold particles to engage with any antibiotic present in the milk. The test strip is then inserted into the sample well with the arrows pointing downward initiating capillary flow up the strip. Any gold particles that are not complexed with antibiotics present in the milk will bind to their respective test line, forming a signal (red line) at that position. Each test strip is imprinted with three test lines and one Control line (C-line)at the top. The top test line specifically detects for beta-lactams, the middle test line detects for tetracyclines, and the bottom test line detects for sulfonamide antibiotics. If the binding protein on the gold particle has engaged with either beta-lactams,tetracyclines, or sulfonamide antibiotic residues present in the milk sample, the gold particle will flow past the test line corresponding to that antibiotic and reach the C-line. For visual interpretation of the test results, any test line signal intensity that is stronger than the signal at the C-line indicates a negative result. Signal at any test line which is equal or less intense compared to the C-line indicates the presence of the corresponding antibiotic in the milk. The greater the reduction in signal intensity at the test line, the greater the concentration of beta-lactam, tetracycline or sulfonamide antibiotic residues present in the milk. The assay is also designed to simultaneously detect sulfonamide, tetracycline and beta-lactam antibiotics.

Sensitivity (Detection Limit)

Beta-lactam Antibiotics
Penicillins		Cefalosporins
Antibiotic (MRL)	Detection limit (μg/L)	Antibiotic (MRL)	Detection limit (μg/L)
Penicillin G (4)	3-4 ppb	Ceftiofur (100)	75-100 ppb
Ampicillin (4)	4-5 ppb	Cephapirin (60)	6-15 ppb
Amoxicillin (4)	4-5 ppb	Cefazolin (50)	35-50 ppb
Cloxacillin (30)	4-8 ppb	Cefoperazone(50)	5-20 ppb
Oxacillin (30)	4-8 ppb	Cephquinome (20)	10-20 ppb
Dicloxacillin (30)	5-8 ppb	Cephalonium (10)	4-8 ppb
Nafcillin (30)	15-30 ppb
Sulfonamide Antibiotics		Tetracycline Antibiotics
Antibiotic (MRL)	Detection limit (μg/L)	Antibiotic (MRL)	Detection limit (μg/L)
Sulfmethazine (100)	25-50 ppb	Tetracycline (100)	50-100 ppb
Sulfamethoxazole (100)	25-50 ppb	Chlorotetracycline (100)	15-50 ppb
Sulfadiazine (100)	50-75 ppb	Doxycycline (100)	5-20 ppb
Sulfathiazole (100)	75-100 ppb	Oxytetracycline (100)	50-70 ppb
Sulfadimethoxine (100)	50-75 ppb
Sulfaquinoxaline (100)	75-100 ppb
Sulfapyridine (100)	2-4 ppb
Sulfamethoxypyridazine (100)	3-4 ppb
Sulfamethizole (100)	40-50 ppb
Sulfamerazine (100)	25-50 ppb
Sulfachloropyridazine (100)	25-50 ppb

 

REAGEN LLC is an indrustry-leading biomedical enterprise focused on designing and producing a broad range of ELISA kits, including clinical diagnostic kits, food and feed safety kits, and veterinary disease kits. we also manufacture microplate readers, plate washers, and related instruments and equipment.