Trastuzumab (Herceptin ) is indicated for the treatment of HER2-positive breast cancer, and adjuvant therapies for metastatic gastric cancer and gastroesophageal cancer. Serum concentration of Trastuzumab may predict some clinical outcome during therapy. It is also possible that the surveillance of circulating Trastuzumab concentration during therapy represents a direct factor for immunogenicity and some other side effects. Identification of biomarkers and risk factors for adverse drug reactions that might be related to serum concentrations, and maintaining the effective minimum concentration of Trastuzumab in order to potentially avoid some side effects, might be beneficial using a reliable method.
Reagent preparation Prepare only the appropriate amount of required reagent on the day of use. Store all reagents as per instructions stated on the label. 1. Wash Buffer (1X) Preparation: Dilute wash buffer concentrate with ultra-pure water 1/10 before use (for example add 10mL concentrate to 90mL ultra-pure water). Mix well. 2. Detection Reagent (1X) Preparation: Dilute detection reagent with assay buffer 1/1000 before use (for example add 10ul concentrate to 10ml of assay buffer). Mix welll. 3. Preparation of Calibrators: Prepare calibrators with concentrations ranging from 1000 ng/mL to 62.5 ng/mL. The following is an example calibrator curve.
Results calculation 1. Construct a standard curve by plotting the absorbance obtained from each standard against concentration. Use a 4 or 5 parameter curve fit. Alternatively a log-log curve fit may be used. 2. The concentration of the unknowns can be read directly from this standard curve using the absorbance value for each sample. 3. Any sample undiluted or diluted still reading greater than the highest standard should be diluted appropriately with calibrator diluent and retested. If the samples have been diluted, the concentration determined from the standard curve must be multiplied by the dilution factor.
Sample preparation Dilute calibrators and test samples 1/50 with assay buffer (for example add 5uL of prepared calibrator or sample to 245uL of assay buffer). Mix well. Do not store diluted samples.
Intra-assay coefficient of variation (CV) <10%. Inter-assay CV <10%.
Notes
This kit is compatible with EDTA-plasma, heparinplasma and serum samples. Samples can be stored at or below -20°C for up to 1 year.
Usage Notes
Quantification of Trastuzumab in biological matrices
Protocol
The Trastuzumab ELISA kit is designed to measure free Trastuzumab with high specificity and sensitivity . This assay employs the sandwich enzyme immunoassay technique. A precoated anti-Trastuzumab 96 well plate is provided. Calibrator, quality control samples and test samples are pipetted into the appropriate wells. Trastuzumab present in biological matrices is bound by the immobilized capture antibody. After washing away any unbound substances, enzyme linked detection antibody is added to the wells. The plate is washed to remove any unbound antibody-enzyme reagent and a substrate solution is added to the wells for color development. The color development is proportional to the amount of Trastuzumab present in test samples and the concentration is calculated from the standard series.
Gene ID
2064
Applications
ELISA
Storage
-20C, 1 year
Reviews of Trastuzumab (Herceptin) Pharmacokinetic ELISA