Though ICG is the most widely used fluorophore in clinical trials, it has no characteristic of tumour imaging as its short half-life and fast excretion rate via the bile. Therefore, researchers have designed new type of fluorophores by conjugation with some molecules (antibodies, peptides, etc.) to enhance their affinity for specific cancer types. IRDye 800CW is the most common used fluorophore for creating fluorescently labelled imaging agents, as it has the similar excitation and emission wavelengths as ICG, but unlike of ICG which has no reactive functional group, IRDye800CW can be functionalized with either an n-hydroxysuccinamide (NHS) or maleimide reactive group which allows it to be conjugated with some biomolecules (Fig. ). In the last decade, clinical trials have reported IRDye800CW labelled cetuximab or panitumumab using in the cases of EGFR (epidermal growth factor receptor) expressing tumors such as head & neck cancers or high-grade glioblastoma , IRDye800CW labelled bevacizumab for VEGF-A (vascular endothelial growth factor) expressing cancers (breast cancer or oesophagus cancer ) and rectal/colon cancer , pancreatic cancer . (Table ). The conjugates of antibodies and IRDye800CW are tumor targeting, and can be used to detect cancer or track the sentinel lymph nodes for metastatic disease identification intraoperatively. But with the half-life usually more than 10 days, the surgeries have to be scheduled 1-7 days after the intravenous infusion of IRDye800CW labelled antibodies in order to operate at optimal tumour-to-background ratio. For now, all the clinical trials on IRDye800CW labelled antibodies are staying on the investigation of feasibility or safety or optimal dose discussion, and more trials have to be done to process into a further phase.