SIRPA and neoplasm: used a pH‐sensitive linker to combine azide‐modified EVs with dibenzocyclooctyne‐modified antibodies of CD47 and signal regulatory protein alpha (Figure 3b).[65] When injected without modification, most EVs are preferred to retain in liver or spleen rather than in the desired tumor sites.[66] Through covalently conjugating EVs with cyclic RGD peptide, enhanced antitumor effects can be improved by targeting tumor cells.[67] In addition, noncovalent strategies have also been leveraged to provide stable modification on EV membranes.