Common Methods:
Bradford Assay:
Utilizes a dye-binding technique, inducing a color change in the presence of proteins. Suitable for a wide range of sample types.
Lowry Assay:
Offers high sensitivity, particularly useful for low protein concentrations.
Bicinchoninic Acid (BCA) Assay:
Renowned for compatibility with various sample types and ability to work with reducing agents.
UV Absorption at 280 nm:
Based on the principle that proteins absorb light at this wavelength, providing a rapid and straightforward method for determining protein concentration.
Nanodrop:
Nanodrop spectrophotometry accurately measures protein and nucleic acid concentrations using minimal sample volumes. This quick and efficient method provides reliable results, supporting research and development in the biopharmaceutical industry.
Electrophoretic Methods
Electrophoretic methods are pivotal in ensuring the quality and safety of products manufactured under GMP standards. Common techniques include SDS-PAGE, IEF, and Western Blotting.
Techniques:
SDS-PAGE (Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis):
Separates proteins based on molecular weight. Essential for assessing protein purity, ensuring product consistency, and detecting contaminants.
IEF (Isoelectric Focusing):
Separates proteins based on their isoelectric point (pI). Crucial for characterizing charge heterogeneity and detecting post-translational modifications.
Western Blotting:
Extends SDS-PAGE and IEF for specific detection of target proteins within complex mixtures. Confirms protein presence, verifies identity, and quantifies concentration. Indispensable in pharmaceutical research and quality control.
These methods allow manufacturers to monitor product quality, consistency, and safety, ensuring deviations from established standards are promptly corrected.
Capillary Electrophoresis (CE)
Capillary Electrophoresis (CE) is a powerful analytical technique used in the pharmaceutical and biotechnology sectors. It ensures the quality and safety of products, including biopharmaceuticals, proteins, and nucleic acids.
Methods:
CE-SDS:
Assesses protein purity and identity. Separates proteins based on size and charge, confirming the presence of target proteins and identifying contaminants.
CE-IEF:
Determines the isoelectric point of proteins, influencing behavior and stability. Aids in biopharmaceutical development
and characterization.
Capillary Zone Electrophoresis:
Analyzes small molecules and charged compounds. Provides precise quantification and identification of analytes in complex mixtures, essential for quality control and product validation.
