We also obtained ex vivo NIR imaging results of major organs and tumours at 72 h post-injection (Supplementary Fig. 15) and the results showed that the both tumour and liver yielded a strong signal in Ch1 imaging, while only tumour had strong signal in Ch2 imaging, proving the effective tumour accumulation and hypoxia-specific response of Ir-NP probe. This evidence concerns the gene SUCO and neoplasm.