Enzyme immunoassay (ELISA) for the quantitative measurement of levels of IGF-I in serum or plasma. Human IGF-I measurements are used in the diagnosis and treatment of growth disorders involving the anterior lobe of the pituitary gland. For research use only, not for use in diagnostic procedures.<br><br>
Insulin-like growth factors (IGF) I and II play a pivotal role in regulating the proliferation, differentiation and specific functions of many cell types (1-3). IGF-I is identical with Somatomedin C (Sm-C) (4) and has a molecular weight of 7649 Dalton (5). Its major regulators are growth hormone (GH) and nutrition (6), although its production in specific tissues is affected by a multitude of tropic hormones and other peptide growth factors. IGFs are avidly bound to specific binding proteins (IGFBP). The seven classes of IGFBPs which are known at present (7,8,22). A major problem of IGF-I measurement results from the interference of IGFBPs in the assay. Direct determinations in untreated serum samples (11) give false values because of the extremely slow dissociation of the IGF-I/IGFBP-3 complexes during the assay incubation.<br><br>
IGF-I is present in low concentrations in various body fluids and in conditioned cell culture media of many cell lines. However, the determination of IGF-I in these specimens is particularly difficult due to the presence of IGFBPs usually in excessive amounts. The IGFBP-blocked IGF-I ELISA avoids these problems and allows the simple, correct and sensitive IGF-I determination in numerous samples with minimal expenditure of time.<br><br>
Therefore, various techniques were applied to physically separate IGF-I from its binding proteins before measurement, including (a) size exclusion chromatography under acidic conditions, (b) solid-phase extraction and (c) acid-ethanol extraction (2,12,13). These
- Assay Description:
- 1 hour (RT) + 30 min. (RT) + 15 min. (RT) = 1 hour, 45 min. total clock time
- Catalog number:
- E20
- configuration:
- 96 Determinations, 12x8 removable strips
- controls:
- 2 controls, lyophilized
- design:
- Enzyme immunoassay (ELISA) technique
- FDA Status:
- For research use only, not for use in diagnostic procedures
- MSDS:
- notes:
- The protocol for this product (see above) is intended to serve as an example only. Please refer to the Instructions For Use provided with the assay kit for precise details.
- Other names:
- Insulin-like growth factor-1, IGF-1
- Protocol:
- Sample types:
- Serum or plasma
- Sample volume:
- 20 μL of properly diluted unknown / determination
- standards:
- 5 standards, lyophilized
- Standard range:
- 2 - 50 ng/mL
- storage:
- 2 - 8 °C
- sensitivity:
- 0.091 ng/mL
- Species:
- Human
