FPRs are increasingly recognised for their roles in inflammation, with therapeutic potential for activation or inhibition, depending on context. For example, FPR1 is required for effective immune recognition of tumour cells during chemotherapy but its activation during intracerebral haemorrhage exacerbates brain inflammation. Imaging of FPR1 is of growing interest for diagnostics. For example a fluorescent FPR1 peptide-based probe was recently used to visualise infiltrating neutrophils during abdominal aortic aneurysm in mice, and imaging revealed the location of granulomas associated with Tuberculosis infection. A greater understanding of the fundamental biology of this receptor (e.g. dimerisation, trafficking) and its expression and localisation in cells and tissues, would aid in defining when and where FPR1 could be targeted for therapeutic or diagnostic gain. We sought to design here a chemical probe to label FPR1 to irreversibly introduce a fluorophore to this receptor to study its cell biology in situ.