Plant organelle/membrane isolation
- Mitochondrial fraction
- Nuclear fraction
- Plasma membrane fraction
- Thylakoid extraction
- Arabidopsis thylakoid preparation
- Arabidopsis thylakoid extraction
- Arabidopsis lumen extraction
- BBY preparation
- Chlorophyll measurements
- PSII RC extraction for cryo-EM
- Extraction of leaf proteins
- Diatom protein extraction
- Phenol protein extraction
- Protein extraction from grasses
- Ponceau membrane staining
- TCA acetone precipitation method
- Collection of articles
- Western blot protocol
- Western blot video tutorial
- Peptide neutralization/competition assay
- Simultaneous Western blot
- Quantitative Western blot
- Quantitative Western blot video tutorial
- Western blot troubleshooting
- Western blot using IgY
- Dot blot
- ELISA
- Immunoprecipitation
- Immunoprecipitation/IgY
- Immunohistochemistry
- Anti-KLH antibody removal
- Yolk delipidation
- Meiotic staining
Technical information
Antibody typesPurification
- Antibody purification
- Antibody purification - small amount of protein
- IgY purification methods
- Protein purification using antibodies
- Elution of antibodies from affinity columns
Technical information > Molecular weight and isoelectric point of various animal immunoglobulins
| Immunoglobulin | Approximate MW/ kDa (g·mol−1) | Number of subunits | pI* | A280 (mg/ml) |
|---|---|---|---|---|
| IgA, human | 162 | 4 | n.a. | 1.34 |
| IgE, human | 190 | 4 | n.a. | 1.53 |
| IgG, goat | 144 | 4 | n.a. | 1.30 |
| IgG, human | 153 | 4 | 6.6 - 7.2 | 1.38 |
| Subclass IgG1, human | 146 | 4 | 8.6 ± 0.4 | n.a. |
| Subclass IgG2, human | 146 | 4 | 7.4 ± 0.6 | n.a. |
| Subclass IgG3, human | 170 | 4 | 8.3 ± 0.7 | n.a. |
| Subclass IgG4, human | 146 | 4 | 7.2 ± 0.8 | n.a. |
| IgG, mouse | 155 | 4 | ∼ 7.0 | 1.40 |
| IgG, rabbit | 150 | 4 | 6.5 - 7.5 | 1.36 |
| IgM, human | 950 | 20 | 5.5 - 7.4 | 1.33 |
*Isoelectric point (pI) values are theoretical calculations based on the distribution of charged amino acid residues in a protein sequence. Experimental conditions, such as buffer composition and pH, can also influence the behavior of proteins in solution. Beyond this, factors such as post-translational modifications and specific characteristics of the antibodies can also effect the pI. Therefore, precise determination of the pI for a particular protein often requires experimental techniques such as isoelectric focusing or capillary electrophoresis.
Polyclonal antibodies do not have a set isoelectric point as they are a mixture of various classes.
Mouse immunoglobulin subclasses: IgG1, IgG2a, IgG2b, IgG2c, IgG3
Rabbit immunoglobulin subclass: IgG (only one)
Rat immunoglobulin subclasses: IgG1, IgG2a, IgG2b, IgG2c
For more extensive information on different types of immunoglobulins, please visit the following pages: IgG, IgM, IgY
Average serum concentration of human IgGs (mg/ml):
- IgG1: 8
- IgG2: 4
- IgG3: 0.8
- IgG4: 0.4
Antibodies to unconjugated human immunoglobulins
Immunoglobulins from various species in different purity grades
