Protein Forest
Protein Forest has developed a technological breakthrough that enables the rapid fractionation of proteins by their isoelectric points.
Our digital ProteomeChip technology platform is based on established electrophoresis principles, but is faster and easier to use.
The dPC™ product platform is used to enhance the sensitivity and performance of protein analysis techniques, such as mass spectrometry, chromatography and immunoblotting, by providing a rapid and reliable separation of complex protein mixtures into fractions that are easier to analyze.
Proteins are fundamental macromolecules that drive virtually all biological processes. They function as enzymes, structural components, signaling molecules, and transporters, among many other roles. Composed of amino acids linked by peptide bonds, proteins adopt complex three-dimensional structures essential for their function.
Understanding and studying proteins is crucial in fields such as molecular biology, biotechnology, and medicine. To analyze proteins, scientists must first extract them from biological samples—a process that requires precision to preserve their integrity and activity.
Protein Extraction: Principles and Techniques
Protein extraction is the process of isolating proteins from biological materials such as cells, tissues, or whole organisms. The goal is to obtain functional, high-purity proteins for downstream applications like enzymatic assays, structural studies, or drug development.

1. Sample Preparation
The first step in protein extraction involves preparing the biological sample:
- Tissue or Cell Disruption – Proteins must be released from cells or tissues by breaking membranes using mechanical, chemical, or enzymatic methods.
- Choice of Buffer – The extraction buffer maintains protein stability, prevents degradation, and provides optimal conditions for solubility. Buffers typically contain:
- pH stabilizers (e.g., Tris-HCl)
- Salt (e.g., NaCl, KCl) to maintain ionic balance
- Detergents (e.g., SDS, Triton X-100) to disrupt membranes
- Protease inhibitors to prevent degradation
2. Protein Extraction Methods
Different techniques are used to lyse cells and extract proteins, depending on the sample type and target protein.
a) Mechanical Disruption
- Sonication – Uses high-frequency sound waves to break open cells.
- Homogenization – Physically grinds or shears cells using high pressure or grinding tools.
- Freeze-Thaw Cycles – Repeated freezing and thawing of samples disrupts cell membranes.
b) Chemical and Enzymatic Extraction
- Detergents (e.g., SDS, Triton X-100) dissolve membranes and release proteins.
- Enzymes (e.g., lysozyme for bacterial cells, proteases for breaking down unwanted proteins) can assist in lysis.
3. Protein Purification
After extraction, proteins must be purified to remove contaminants:
- Centrifugation – Separates soluble proteins from cell debris.
- Precipitation – Salting-out (e.g., ammonium sulfate precipitation) isolates proteins based on solubility.
- Chromatography – Techniques like size-exclusion, ion exchange, and affinity chromatography help in purifying specific proteins.
4. Protein Quantification and Analysis
To confirm successful extraction, proteins are quantified and analyzed using:
- Bradford Assay / BCA Assay – Measures total protein concentration.
- SDS-PAGE and Western Blot – Separate and detect specific proteins.
- Mass Spectrometry – Identifies protein composition and modifications.