Screening of antibiotics

Hi everyone.

In our lab we are currently considering implementing screening of antibiotics. The most of the samples that we could potentially get are meat and milk products. As I understand, the preparation of this types of samples is a little bit complicated, especially for primotest and delvotest. Do you maybe have any suggestion, any idea of a method for doing antibiotics?

How are you doing this analisys in your lab?

Tnx in advance.

The milk processors that I have been in  use the charm test for antibiotics. what milk products are you testing? (fluid white, cultured, flavored, etc.  I don't have any meat experience - sorry.  

Well, we are currently subcontracting our antibiotic analysis. And the plan is to do by ourselves. The main problem is that it is possible to use premi and delvo tests for milk and meat, but majority of our samples are products ( white cheese, hard cheese, cream, sour cream, sausages, ham, smoked meat etc. ). And basically, what we are trying to do is to avoid four plates method, because it is old, time consuming method and it has low sensitivity. So we are looking for any type of quick, screen test analysis, that is workable for products. Or maybe, does anyone have experience with sample preparation of meat and milk products for premi and delvo? Is it at all workable?

Also, is anyone working HAPLC quantification of antibiotics? What are your experiences,problems,dilemmas? 

Anything, just not to do 4 plates. I am desperate :)

Best regards,

Janie

Dear colleague,

your problem is stil not tatally solved in a comfortable way. Microbial Inhibition Assays (MIAs) like Devo o Premitest could be used (with some modifications), but be aware that they are not sensitive enough for some important classes including, for instance, chloramphenicol (CAP). Even some governmental labs in Italy are still screening by the 4 or 5 plates method, that is a little better and provide you at the end with some informations about which class the antibiotic belongs, but cannot detect CAP and still have not satisfactory LODs for other molecules.

My suggestion is to operate considering the real risk of an occurrence. You should very carefully choose an external lab (not only accredited generically, but with the ISO17025 for these tests and able to provide you results of Proficiency Test with your kind of samples). Monitor for about one year the regular supplier and identify which are the molecules that sometimes are in the milk of meat. Then you could choose to use immunoassay kits (preferably ELISA) to maintain a strict control of such molecules, as well for SULFA, TETRA, CAP (milk, meat) and nitrofuran metabolites (meat).

Best Regards

Maurizio

paleologo.maurizio@gmail.com