|
|
|
|
Services for Identification and Assay Sample Preparation
Your attention to the following will expedite assays and prevent errors:
1. Samples must yield at least 0.20 mL and must be aseptic. If smaller volumes are provided, the lower limit of detection may be increased. Since the necessity for repeat assays does arise, although infrequently, we suggest that samples >=0.4 mL be provided whenever possible if the suspected titers are low.2. CLINICAL SAMPLES WITH POTENTIAL INFECTIVITY (ESPECIALLY HUMAN IMMUNODEFICIENCY VIRUS AND VIRAL HEPATITIS) MUST BE SO DESIGNATED in a packing list, and must be shipped using recommended practice for etiologic agents [18]. Sterile 2 mL cryovials having O- rings or sterile 1.5 to 2- mL microcentrifuge tubes are recommended primary containers. Samples should be stabilized with at least 2% serum or 1 mg per mL other protein if there is any question concerning stability. Samples which are accumulated intermittently should be stored at - 70 degrees C prior to shipping. Samples need not be absolutely sterile good aseptic technique will suffice. Samples should not be sterilized by filtration.
3. To facilitate your interpretation of results, all sample preparation must occur in your laboratory. If you wish to measure acid- labile activity, split the sample and acidify one portion (>= 0.2 mL) to pH 2- 3 (see Table 2), incubate overnight at 4 degrees C, then neutralize and freeze both portions for assay.
4. Please code the samples numerically with consecutive integers only! Samples not so labeled will be returned.
5. Please provide us with a rough estimate (order of magnitude or “literature” values) of the titers of samples, groups of samples, or the entire range of titers. Please also describe briefly the origin of samples. We must be able to infer titration ranges and include appropriate standards.
6. Samples should be shipped frozen on dry ice. Please confirm shipping and receiving dates prior to shipping.
7. Cell stocks for assays are usually set up on the preceding Friday. If samples are received by Friday, assays will generally begin on the following Tuesday or Wednesday, and results will be calculated and reported at the beginning of the following week.
|
