Colorimetric immunostaining with 2 primary antibodies on free-floating sections

CAT# SI103 Category

Colorimetric immunostaining with 2 primary antibodies on free-floating sections


This service includes tissue preparation, sectioning, immunostaining, mounting, coverslipping and labeling of slides. As a result, you will receive up to 60 immunostained sections per brain or per tissue block ready for microscopic observations.

Procedure:  Following cryoprotection, tissue will be rapidly frozen in isopentane pre-cooled to -70°C. The frozen tissue will then be cut on a cryostat and collected in our unique section cryoprotection solution (cf. Products, Cat. #PC101). Subsequently, sections cut through various levels (or the levels of your choice) will be processed free-floating for immunostaining with 2 specific antibodies according to the avidin-biotin-complex (ABC) method¹ (cf. photo samples below).

BrdU and NeuN double-immunostaining. 30 µm cryostat section was cut from the hippocampal dentate gyrus of a mouse sacrificed 24 hrs after the injection with 5-bromo-2-deoxyuridine (BrdU). The section was processed free-floating for BrdU-(blue) and then for NeuN-(red) immunoreactivity according to the ABC-AP method (cf. also photo samples of SI203).
C-fos and kir2.3 double immunostaining. 30 µm cryostat section through the rat hypothalamus was processed free-floating for kir2.3- (brown) and then for c-fos- (red) immunoreactivities according to the avidin-biotin-complex method. Note nuclear labeling of c-fos immunoreactivity.


  • A quotation is required before placing an order.
  • The investigator needs to provide fixed tissue and the specific antibody.
  • Please contact us for more information.


  1. Hsu S. M., Raine L. and Fanger H. (1981) Use of avidin-biotin-peroxidase complex (ABC) in immunoperoxidase techniques: a comparison between ABC and unlabeled antibody (PAP) procedures. J. Histochem. Cytochem. 29, 577-580.