Frequently Asked Questions about DIARECT Antigens

How should I handle antigens upon receipt?
Upon receipt, our antigen products should remain frozen until use. We recommend thawing the solutions at room temperature, taking care that they do not remain at room temperature for longer periods of time. Mix the antigens gently before use.
If you only plan on using a portion of the product, please thaw and dispense into aliquot volumes that are most practical for your application. Please note that we can only guarantee shelf life if the antigens are not repeatedly frozen and thawed.

Can I use antigens that arrive unfrozen?
No, we do not recommend using antigens without a guaranteed cold chain. If you receive a thawed product please inform our customer service immediately. Regarding dry ice shipments please visit our web site for detailed information on temperature tests.

What is the shelf life of your products?
Most of our autoantigen products have a guaranteed shelf life of five years unless otherwise noted on our Data Sheets and Certificates of Analysis. This is provided that they are kept frozen at -70°C or less.

How can I benefit from DIARECT´s Reservation System?
We offer the reservation of a specified amount of antigen(s) (up to a whole production run). Usually the amount of antigen under reservation is sufficient for our customers' manufacturing needs for at the most 18 months. You simply inform us of your antigen requirements for this period, and after approximately four months we will give you feedback regarding the accuracy of your estimate. The reservation system also includes providing the customer early enough with samples of new lots of the respective antigen. This allows for a smooth transition when evaluating for the qualification of a new lot for subsequent reservation.

What does Ec / BV stand for?
BV and Ec represent the type of expression system that was used to produce the antigen of interest. BV stands for DIARECT's baculovirus / insect cell expression system, while Ec stands for DIARECT's E. coli expression system.