What are the recommended brands of primary antibody reagents for Western blot protein detection?

CST, Abcam, Invitogen/Thermo, Millipore/Sigma are common choices among imported brands. If the target protein is low expressed, don't just look at the brand, focus on checking whether the antibody data page has made tissue samples and low expression models. The background weight may not necessarily be the antibody itself, and factors such as blocking, dilution, membrane washing time, and secondary antibody concentration can also affect it. The delivery time of three weeks is indeed long. You can find a domestic agent who has stock, or ask the salesperson to apply for packaging samples. Most regular equipment within a budget of 3000 can be covered, but it is necessary to confirm whether the specification is 100 µ L or 100 µ g, and to suggest a dilution ratio to calculate the cost per film.

A more practical approach when selecting an antibody is to first confirm the protein molecular weight, subtype, and modification site, and then search for the antibody in reverse. Multi antibody sensitivity is usually higher and suitable for low expression, but batch heterogeneity is greater; Monoclonal antibodies have good specificity, but may not recognize denatured epitopes. When organizing samples, attention should be paid to whether the lysis is sufficient, whether the sample size is sufficient, and if necessary, enrichment or increasing the sample size should be done. Background weight can optimize both the dilution of primary antibody and the concentration of secondary antibody simultaneously, by changing the blocking solution (such as 5% BSA or skim milk powder comparison) and washing conditions. Many so-called antibody problems are actually caused by the system not being properly adjusted.

Domestic brands can look at Proteintech, Huaan Bio, Zheneng, Abclonal, BiYuntian, Affinity, especially Proteintech data is relatively complete, many antibodies have WB and IHC plots. Domestic products are cost-effective, but batch consistency needs to be looked at by yourself. It is recommended to first buy a 20 µL small package or apply for a trial package, use the same batch of tissue lysate to run the glue, set a negative-positive control and internal reference, and observe the location of the target band, miscellaneous band and background. Don't buy in large quantities directly because it's cheap, try it before ordering. Some domestic manufacturers can also arrive within a week, which is more flexible than imports.

In terms of sourcing, shelf life and trial packs are more important than brand rankings. The three-week delivery period has a great impact on the progress of the experiment. You can give priority to finding domestic spot or domestic manufacturers. The 3000 yuan budget has options in imports and domestic production, but different specifications vary greatly. Ask for the concentration, volume, recommended dilution ratio and number of runnable membranes when inquiring. After obtaining the new antibody, it is recommended to compare it with the old antibody. At least look at the target band and the internal reference band to confirm that the specificity has not decreased. If the supplier can provide inter-batch validation data or literature citations, the priority can be increased.