Text X362.2IE v1802

XEMAtest Milk 
Rapid immunochromatographic test for qualitative determination of milk antigen in foods, 
kitchen and production facilities
Version of the test I (1406)
Milk of cow (Bos taurus) and the products of its processing (dairy products) are the basic parts of human alimentation. Other related species – zebu (B. indicus), domesticated yak (B. grunnius), banteng (B.javanicus) and related genuses (buffaloes, goat, sheep, horse) are common sources of milk for human consumption in some geographical areas. 
Milk allergy can display the variety of symptoms from mild oral allergy or hives to severe life-threatening systemic reactions, i.e. anaphylactic shock or bronchial asthma. True (IgE- or IgG-antibody mediated) allergy to milk proteins is clinically distinguishable from milk intolerance caused by lactase deficiency. 
Allergy to milk proteins is one of most frequent allergies especially in infants and children, affecting 0.5%-3% of the populations in different age and geographical groups.
A target distribution of allergy to three major milk proteins (caseins, alpha-lactalbumin and beta-lactoglobulin) is almost equal among allergic patients, with slight predominance of caseins. The protein composition of dairy products is very variable, for example with substantial enrichment by casein in cheese and predominance of two other proteins in whey products.

Consumption and handling of milk is regulated by some religious confessions. 
Food Allergen Labeling and Consumer Protection Act (FALCPA) identified that milk allergy is one of the 8 major food allergies, and milk should be labeled on the package.
In EU milk is included into the list of allergens established by European Food Safety Authority, which must be indicated in foods according to EU law No 1169/2011 Annex II
XEMAtest Milk detects one of the major allergens – beta-lactoglobulin. This protein is a member of lipocalin family and comprises approximately 10% of dry weight of defatted milk proteins
XEMAtest Milk is based on immunochromatographic principle (lateral flow). The target antigen is bound by specific antibodies attached to colored microparticles. Then this complex migrates to the test line where binds to another specific antibody to form a colored line indicating positive result.
The test is applicable for qualitative detection or semiquantitative measurement of target antigens in the samples of complex foods and surface swabs. The qualitative detection is usually done for screening and the semiquantitative measurement is applied for monitoring or comparative studies.

TEST SENSITIVITY AND SPECIFICITY
ХEMAtest Milk utilizes utilizes a combination of monoclonal antibodies which enables to detect milk specific antigen in all milk species used in food industry.
ХEMAtest Milk does NOT detect human milk and the antigens of animal meats, blood and other parts of the animal body.
The sensitivity of ХEMAtest Milk varies 3-5 times between different species (goat, camel, horse) however the test detects all edible species tested to date.

A sensitivity of ХEMAtest Milk (LOD, limit of detection) by volume per volume is at least 10 ppm for pasteurized milk with the range of detection (ROD) 10-50000 ppm. For powdered milk the sensitivity is at least 1 ppm by weight per weight of dry material. The sensitivity of the test does not decrease with dry heating of the food up to 160 °C but may decrease in fat-rich environment (e.g. in cream).
In dry spots or other types of the material collected by wet swabs according to present instruction, the LOD is approximately 80 ng/ 100 square centimeters.
PLEASE NOTE: the sensitivity is calculated for the target antigenic material content in solid material extracted by the method described below, (solid/liquid ratio 1:10 wt/vol). The sensitivity of the test may be upgraded by lowering of the solid/liquid ratio, however this may result in thick liquid which will not penetrate into the test strip. The LOD data for liquid samples are 5x lower with standard procedure, ie with regular liquid specimens the test reaches higher sensitivity.
The sensitivity of ХEMAtest Milk may be also compared to the allergen preparation used for skin testing obtained from different manufacturers – it is approximately 50.000 to 100.000x fold dilution.
More details of test performance (sensitivity, specificity, variability, influence of matrix and processing) are available on request or online at www.xematest.com
If the visual test gives unclear results, we recommend to recheck the sample by the quantitative laboratory methods, e.g. Milk ELISA (XEMA, Cat# K362).

CONTENTS
•	2 test strips individually packed into sealed foil pouches;
•	2 Specimen collection tubes;
•	1 vial of Specimen extraction buffer, 10 ml;
•	Instruction for use.

SPECIMEN HANDLING 
The specimens should be brought to temperature range +18...+35 °C before use; testing of colder specimens diminishes the sensitivity of the assay; testing of hot specimens is NOT possible!
The test is designed to detect the target antigen in different types of the material, please select the relevant section of the text below.

TEST PROCEDURE FOR SOLIDS
1.	Allow the test strips to reach room temperature for 5-10 minutes before opening the pouches. 
2.	Put a small piece of tested material (0,1-0,5 g) into a Specimen collection tube. If the balances are available, record the actual weight in grams. 
3.	If the accurate volume measurement tool (pipette) is available, calculate required Specimen extraction buffer volume as 10x actual weight (for example, if the weight is 0,23 g, add 2,3 ml of the buffer). Otherwise, add not more than half of tube volume of Specimen extraction buffer. Adjust the sensitivity of the assay if the weight/volume ratio is different from 1:10.
4.	Screw the cap securely onto the tube and shake vigorously for 15 – 30 seconds or use the vortex mixer. Allow to settle for 2 minutes. 
5.	If the liquid is thick and cloudy, it may not penetrate into the test strip, and testing fails. To avoid it, allow to settle for longer period (up to 6 hours). The extract may be also filtered by textile material or centrifuged.
6.	Open the pouch, taking care not to damage the test strip. Dip the test strip into the liquid layer, do not touch the solid settled down on the bottom.
7.	Allow the strip to remain in the solution for 5 – 10 seconds. Remove the test strip and place onto a clean horizontal surface; do not touch or move the test strip for 10 minutes. Read the test result. 

CAUTION: ENSURE THE TEST STRIP IS DIPPED AS SHOWN IN A FIGURE. THE DIRECTION AND THE DEPTH OF IMMERSION MUST BE AS SHOWN FOR CORRECT OPERATION. 

TEST PROCEDURE FOR LIQUIDS
The limitation for liquid specimens is their viscosity and turbidity (presence of particulate matter). If the specimen is viscous and cannot reach the test zone of the test strip, it should be diluted by Specimen extraction buffer right in the Specimen collection tube or separately. In this case, the sensitivity of the test should be adjusted by dilution factor. Cloudy specimens should be allowed to settle, filtered through textile material, or centrifuged.
1.	Allow test strips to reach room temperature for 5-10 minutes before opening the pouches. 
2.	Collect 1 ml of liquid specimen into a Specimen collection tube (by first marker on the tube wall or using a pipette).
3.	Add an equal volume of Specimen extraction buffer, screw the cap securely onto the tube and mix by shaking or use the vortex mixer.  If the liquid is cloudy, allow to settle, then follow the instructions from point 5 of test procedure for solid materials outlined above
TEST PROCEDURE FOR SURFACE SWABS 
1.	Allow test strips to reach room temperature for 5-10 minutes before opening the pouches.
2.	Add 1 ml of Specimen extraction buffer to the tube into a Specimen collection tube (by first marker on the tube wall or using a pipette)
3.	 Place the swabbing tool (for example, cotton tip) into the tube, rinse the swabbing tool in the buffer
4. Squeeze off any excessive liquid off the swabbing tool against the tube wall
5. Swab the tested surface with special attention to suspected spots. 
6. Put the swab back into the tube containing the rest of the buffer and shake vigorously for 15 – 30 seconds or use the vortex mixer.
7. Remove the swab from the tube and follow the instructions from point 5 of test procedure for solid materials outlined above.

INTERPRETATION OF THE RESULTS
Test is considered POSITIVE if TWO colored lines appear in the test zone.

Test is considered NEGATIVE if only ONE colored line is clearly visible.
 
If NO colored line is formed, the test is INVALID. 

Try to repeat it with another test strip, check the correct specimen handling and test procedure, expiry date and storage conditions.
PRECAUTIONS
*The test strips should be stored at +10...+30 °C
*Use the test within 10 minutes after opening the pouch because the test strips are very sensitive to moisture
*Do not touch the reaction membrane
*Do not use the test strip if its pouch is torn, or test strip is broken or damaged
*The test strips are disposable; do not use them repeatedly
*Do not use the test strips beyond the expiration date

MANUFACTURER: 
Xema group of companies
www.xematest.com