Rapid tests to determine residues
β-lactams, tetracyclines, chloramphenicol, streptomycins, cephalexin
in Milk , whey.
General information:
The kit is used for the determination of β-lactams, tetracyclines, chloramphenicol, streptomycins, cephalexin (penicillin G, cloxacillin , amoxicillin , oxacillin , nafcillin , ampicillin , dicloxacillin , benzathine penicillin (benzicillin), hetacillin , piperacillin , proca in-penicillin , ticarcillin , cefkin , cephalonium , ceftiofur, cefapirin, cefoperazone , cefacetril, cefazolin, cefadroxil, cefoxazole, cefotaxime , cefuroxime , tetracycline , chlortretracycline , doxycycline , oxytetracycline, streptomycin, dihydrostreptomycin , chloramphenicol , cephalexin ) in raw, pasteurized, sterilized, reconstituted milk powder, whey, whey dry reconstituted milk.
Storage conditions:
Test kits should be stored at 2-8 °C. Do not freeze!
Shelf life: 12 months. The batch number and expiration date are indicated on the packaging.
Operating principle:
Test kit detection limit: |
| Table 1 | ||
β-lactams | ||||
Penicillins | Detection limit | Cephalosporins | Detection limit | |
ppb (µg/l) | ppb (µg/l) | |||
|
| |||
Penicillin G | 1-2 | Tsefkin | 5-7 | |
Cloxacillin | 2-5 | Cephalonium | 3-5 | |
Amoxicillin | 2-3 | Ceftiofur | 60-80 | |
Oxacillin | 4-6 | Cefapirin | 4-8 | |
Nafcillin | 7-9 | Cefoperazone | 3-5 | |
Ampicillin | 2-3 | Cefacetril | 10-20 | |
Dicloxacillin | 2-5 | Cefazolin | 15-25 | |
Benzathine penicillin (Benzicillin) | 2-4 | Cefadroxil | 10-15 | |
Hetacillin | 5-8 | Cefoxazole | 70-90 | |
Piperacillin | 5-6 | Cefotaxime | 25-30 | |
Procaine-penicillin | 2-4 | Cefuroxime | 25-30 | |
Ticarcillin | 3-6 | Cephalexin | 10-15 | |
Tetracyclines | Detection limit | Tetracyclines | Detection limit | |
ppb (µg/l) | ppb (µg/l) | |||
|
| |||
Tetracycline | 6-8 | Doxycycline | 3-4 | |
Chlortetracycline | 5-7 | Oxytetracycline | 7-9 | |
Other antibiotics | ppb (µg/l) | Other antibiotics | ppb (µg/l) | |
|
|
|
| |
Streptomycin | 50 | Dihydrostreptomycin | 50 | |
Chloramphenicol | 0.2-0.3 |
|
|
Set contents: The set includes everything needed for 96 definitions:
- a bottle with a reagent for negative control (does not contain antibiotics );
Sample preparation of milk and whey samples:
Powdered milk , powdered whey: in a suitable flask, dissolve the sample with warm distilled water (according to the current regulatory documentation), mix thoroughly.
Reconstituted milk powder , reconstituted whey powder: samples must be liquid and homogeneous. The samples should be free of clots and product separation phases. The sample temperature must be at least 4 °C, not frozen or heated. Mix the sample thoroughly before testing.
Preparing the Mini-T type incubator:
The analysis can be carried out either with or without an incubator.
When using an incubator, do the following: Place the incubator on a workbench with a flat surface. Connect the power supply to the incubator, and then plug IT into a 220V outlet. Set the switch to the operating position. Next, set the operating temperature to 40 ° C and wait until the device warms up. Once the incubator has reached operating temperature, you can place the sample well in the appropriate hole.
Carrying out self-monitoring of the test kit:
Before starting to work with samples, you should perform a self-diagnosis of the test kit. To do this, use the negative and positive control samples included in the kit. Further work with a kit with confirmed characteristics and detection limits of antibiotics is permitted if a completely negative result is obtained from the analysis of the negative control sample, and a completely positive result from the analysis of the positive control sample.
Add 2 ml of distilled or deionized water to the vial containing the negative control sample and mix thoroughly. The prepared negative standard should be stored at a temperature of 2-8 °C for no more than 24 hours. A frozen negative sample at or below -16°C should be stored in the refrigerator for no more than 30 days. Before use, the negative control should be brought to room temperature and mixed thoroughly. Next, follow the procedure for analyzing milk and whey (read below).
Add 200 µl of the reconstituted negative control sample to the reagent well containing the positive control sample. Using a pipette, mix them thoroughly. After mixing, the sample mixture and the reagent from the well should have a homogeneous structure. Place the well containing the pink antibody reagent into a preheated 40°C incubator or well plate. Pipette 200 µl of the resulting positive control sample and transfer it to the well containing the pink reagent, using the pipette to mix 10 times until the pink color is uniform. Incubate the mixture for 3 minutes. Then place the test strip from the kit into the sample well and incubate for another 7 minutes.
After incubation, remove the test strip from the sample well and interpret the result within 3 minutes.
If the test kit is stored correctly, internal quality control using positive and negative standards may only be performed once before handling the tests, when the test kit box is first opened.
Procedure for analyzing milk and whey:
Read the instruction manual before analysis. Determine how many tests you need, remove the required number of tests from the refrigerator. Kit reagents should be at room temperature. It is advisable to use reagents and test strips from open tubes within 24 hours of removal from the refrigerator to avoid distortion of the results. All kit reagents that are not in use must be stored in the refrigerator. Avoid exposure of reagents to direct sunlight and excess moisture. The reagent in the well is specially dried. Don't think it's spoiled.
Then place the test strip from the kit into the well with the reagent and sample and incubate in the incubator for another 7 minutes at 40 ° C.
Then place the test strip from the kit into the well with the reagent and sample and incubate for another 7 minutes. If the test strip is staining slowly, it is recommended to increase the incubation time by 1 - 2 minutes.
After incubation, remove the test strip from the reagent and sample well and interpret the result visually within 3 minutes, or read using the BMZ 6000 reader (if equipped). To save your result, remove the filter from the bottom end
of the test strip.
Visual interpretation of the result:
Negative result (-): the control line (C) is colored red; the test line corresponding to its antibiotic (T1 ... T5) is colored brighter red than the control line (C) or has the same staining intensity as the control line (C). This means that the sample contains no antibiotics at all, or contains less than the detection limit of the test kit (see Table 1).
Positive result (+): the control line (C) is colored red; the test line corresponding to its antibiotic (T1 ... T5) is absent or has a weaker staining intensity compared to the control line (C). This means that the sample contains a band-matched antibiotic greater than the detection limit of the test kit (see Table 1).
Invalid result: the control line (C) did not appear at all. This means that the test was performed incorrectly or the test strip has deteriorated. The test must be repeated.
Note: