The technical principle and operation process of the multi-channel domestic Western blotting instrument mainly rely on its efficient and accurate protein detection capability. Western blot is an experimental technique used to detect and analyze the expression of specific proteins, widely applied in fields such as molecular biology and medical research.
The following are the technical principles and operating procedures of a multi-channel domestic protein blotting instrument:
Technical Principle
The basic principle of protein imprinting is to separate the protein in the sample by molecular weight through gel electrophoresis, and transfer the separated protein to the membrane through membrane transfer. Then, by binding to specific antibodies on the membrane, the presence and expression level of the protein are detected.
The multi-channel protein blotting instrument mainly improves experimental efficiency by parallel processing of multiple sample channels in one instrument. The core technical principles include:
Protein separation:
Gel electrophoresis (SDS-PAGE): proteins in the sample are separated by polyacrylamide gel electrophoresis. Proteins with smaller molecular weight migrate faster in the electric field, while larger proteins migrate slower, so as to achieve separation according to size.
Protein transfer:
Membrane transfer: transfer the separated protein from the gel to the membrane (usually PVDF membrane or nitrocellulose membrane) by electrotransfer (electrophoresis). Proteins on the membrane will be fixed in specific positions.
Protein detection:
Antibody incubation: By using specific antibodies (usually antibodies targeting the target protein), the antibodies bind to the target protein on the membrane.
Chemiluminescence or colorimetric reaction: Enzyme labeled secondary antibodies bind to target proteins and generate signals through chemiluminescence or colorimetric reactions. The presence and expression levels of proteins are detected by imaging systems.
Multi channel technology:
The multi-channel protein blotting instrument, based on traditional single channel protein blotting, can simultaneously process multiple sample channels in the same experimental process. This is achieved through multiple sample wells and parallel operations, which improves the efficiency of the experiment and the comparability of data.
operating procedure
The operation process of a multi-channel domestic protein blotting instrument usually includes the following main steps:
1. Sample preparation
Collect samples of cells or tissues to be tested.
Use lysis buffer to break down cells and extract proteins.
Quantify the extracted proteins to ensure that an equal amount of protein is added to each sample.
2. SDS-PAGE electrophoresis
Prepare polyacrylamide gel, usually SDS-PAGE gel, SDS (sodium dodecyl sulfate) is used to destroy the structure of protein, make it negatively charged and separate it according to molecular weight.
The samples were loaded into gel, and electrophoresis was carried out in the electric field to separate proteins with different molecular weights.
3. Film transfer
Transfer the protein in gel to PVDF membrane or nitrocellulose membrane. The film transfer process is usually achieved through electrical transfer.
Use a membrane transfer instrument (such as the membrane transfer unit in a multi-channel protein blotting instrument) to adjust parameters such as current, voltage, and transfer time to ensure efficient and uniform transfer of proteins onto the membrane.
4. Blocking
Treat the membrane with a blocking solution (such as 5% skim milk powder or BSA solution) to block non-specific binding sites and prevent antibodies from binding to other parts of the membrane.
5. Antibody incubation
Primary antibody incubation: Place the membrane in a primary antibody solution, usually a specific primary antibody against the target protein. The incubation time can range from 1 hour to overnight depending on the characteristics of the antibody.
Secondary antibody incubation: Incubate with secondary antibodies labeled with enzymes (such as horseradish peroxidase HRP) or other detectable molecules to enhance the signal.
6. Chemiluminescence detection
When using chemiluminescent substrates (such as ECL reagents) for the reaction, HRP enzyme catalyzes the luminescence of the substrate.
Use imaging systems (such as chemiluminescence imaging systems) to capture luminescent signals and generate protein detection images.
The multi-channel design of the multi-channel protein blotting instrument allows for simultaneous signal capture of multiple samples, improving efficiency.
7. Data analysis
Analyze the expression level of proteins based on the brightness and size of the detected bands. The intensity of the band is directly proportional to the expression level of the target protein.
Use software for quantitative analysis of bands and compare them with standard protein scales to calculate the relative expression level of proteins.
Advantages and Features
Multi channel parallel operation: It can process multiple samples simultaneously, improving work efficiency and data comparability.
High degree of automation: By using instruments to automatically control steps such as membrane transfer, antibody incubation, and washing, human errors are reduced.
High sensitivity and high-throughput: suitable for detecting low abundance proteins and capable of processing large amounts of samples.
Wide applicability: It can be applied to various experiments, such as protein expression analysis, antibody specificity verification, protein-protein interaction research, etc.
Conclusion
The multi-channel domestic protein blotting instrument greatly improves the efficiency and accuracy of protein blotting experiments through efficient and automated operation processes. It provides researchers with higher throughput and faster protein detection tools, especially when multiple samples need to be processed simultaneously, demonstrating significant advantages.