Insulin-Like Growth Factor 1 (IGF-1) and Insulin-Like Growth Factor Binding Protein 3 (IGFBP-3) Growth Panel
Method Description Describes how the test is performed and provides a method-specific reference
IGF-1 testing is performed using the IDS iSYS instrument. The IDS-iSYS Insulin Like Growth Factor-1 is a sandwich, chemiluminescent assay. Samples are incubated with an acidic solution to dissociate IGF-I from the binding proteins. A portion of this, along with a neutralization buffer, a biotinylated anti-IGF-I monoclonal antibody, and an acridinium labeled anti-IGF-I monoclonal antibody are incubated. Streptavidin labeled magnetic particles are then added and following an additional incubation step, the magnetic particles are captured using a magnet. After a washing step and addition of trigger reagents, the light emitted by the acridinium label is directly proportional to the concentration of IGF-I in the original sample.(Instruction manual: Immunodiagnostic Systems Inc. Scottsdale, AZ, IS-3900PLv02, 10/19/2011)
The IMMULITE 2000 IGFBP-3 is a solid-phase, enzyme-linked chemiluminescent immunoassay based on murine monoclonal antibodies. The patient sample and alkaline phosphatase-conjugated anti-insulin-like growth factor binding protein 3 (IGFBP-3) antibodies are simultaneously incubated with an antibody-coated bead. During this time, IGFBP-3 in the sample forms an antibody sandwich complex that binds to the streptavidin on the bead. Unbound enzyme conjugate is then removed by washing, after which substrate is added. The chemiluminescent substrate, a phosphate ester of adamantyl dioxetane, undergoes hydrolysis in the presence of alkaline phosphatase to yield an unstable intermediate. The continuous production of this intermediate results in the sustained emission of light. The photon output is directly proportional to the concentration of IGFBP-3 in the sample.(Package insert: IMMULITE 2000 IGFBP-3 Siemens Medical Solutions Diagnostics, Los Angeles, CA, PIL2KGB-11, 2008-07-29)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday 5 a.m. - 12 a.m., Saturday 6 a.m. - 6 p.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Same day/1 day
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test