A multipurpose solid-phase method for protein determination with Coomassie brilliant blue G-250

Area of Science:

• Biochemistry
• Analytical Chemistry
• Protein Analysis

Background:

• Traditional protein determination methods face challenges with interfering substances and limited sample volumes.
• Need for a versatile and reliable protein quantification method applicable to diverse biological matrices.

Purpose of the Study:

• To introduce and validate the multipurpose method for protein determination (MMPD) as an alternative protein assay.
• To assess MMPD's performance with various sample types, including those with interfering substances.

Main Methods:

• MMPD utilizes Coomassie brilliant blue G-250 dye binding to immobilized proteins on paper filter disks.
• Protein quantification is achieved by measuring the absorbance (A600) of eluted protein-dye complexes.
• The method requires small sample volumes (5 microliters) and allows for sample storage up to two weeks.

Main Results:

• MMPD demonstrates quantitative comparability with the Lowry method and other established protein assays.
• Standard curves using bovine serum albumin show two linear segments between 2.5 and 80 micrograms.
• The method is effective for analyzing bovine serum albumin in various solutions and complex biological homogenates.

Conclusions:

• MMPD is a versatile and reliable method for protein determination in both vegetal and animal products.
• It is particularly advantageous when traditional methods are hindered by interfering substances or small sample sizes.
• The ability to store samples prior to analysis adds to MMPD's practical utility.