Bio-Rad Guide Describes the Performance of Standards, a Chemiluminescent Detection Kit In Common Western Blotting Applications

Bio-Rad Laboratories, Inc., a multinational manufacturer and distributor of life science research and clinical diagnostic products, announced today the availability of application note (bulletin 5567A) entitled “Molecular Weight Estimation and Quantitation of Protein Samples Using Precision Plus Protein™ WesternC™ Standards, the Immun-Star™ WesternC™ Chemiluminescent Detection Kit, and the Molecular Imager^® ChemiDoc™ XRS Imaging System.”

Estimation of molecular weight (MW) from western blots is a common technique used to characterize proteins that counts on reliable markers to obtain accurate measurements.

The application note describes the performance of the Precision Plus Protein WesternC standards and the Immun-Star WesternC chemiluminescent detection kit in common western blotting applications. Precision Plus Protein WesternC standards have 10 sharp prestained bands across a broad MW range. These bands are visible at all steps of a western blotting experiment.

In the study described in the application note, the standards provide an accurate method of MW estimation for two independent protein samples on chemiluminescent western blots. While convenient and accurate MW estimation from blots is the principal benefit of the Precision Plus Protein WesternC standards, the benefits of direct band visualization during all steps of the process is a clear advantage over unstained protein markers.

While convenient and accurate, MW estimation from blots is the principal benefit of the Precision Plus Protein WesternC standards. The benefits of direct band visualization during all steps of the process provides a clear advantage over unstained protein markers.

In addition to MW analysis, the application note also demonstrates that it is possible to quantify the amount of a target protein in a western blotting experiment using a known purified control protein to construct a standard curve. This technique can be particularly useful when trying to estimate the amount of a protein expressed in a complex sample such as a cell lysate.

Chemiluminescent Detection
Chemiluminescent detection is a highly sensitive and proven method for visualizing proteins on western blots that can take advantage of the quantitative capabilities inherent in digital imaging systems. The Immun-Star WesternC chemiluminescent detection kit is optimized to produce an intense signal of prolonged duration suitable for the requirements of CCD-based imagers.

As demonstrated in this study, methods using the WesternC chemiluminescent substrate and the ChemiDoc XRS imager to measure signal volume yielded reliable estimates of target protein quantity for both a purified sample and a crude lysate.

Using numerous images, figures, tables, schematics, and diagrams. The application note shows how the Precision Plus Protein WesternC standards, Immun-Star WesternC chemiluminescent detection kit, and ChemiDoc XRS provided a convenient and accurate method for generating high-quality and quantitative results from western blotting experiments.

Availability
Bulletin 5567A is available either from a local Bio-Rad sales office or can be downloaded from via the article webpage.