The present invention relates a to method for preparing a biological sample for use in an immunolabeling process. The invention also relates to corresponding kits for use in the immunolabeling process. The method comprises the following steps: —labeling the biological sample with a labeling component, the labeling component provided with a first enhancer antigen, and —providing a first enhancer antibody, the first enhancer antibody selected to solely bind to the first enhancer antigen, wherein the first enhancer antigen is a non-biological peptide containing one or more “non-natural” amino acids and is not present in the immunolabeling process.