Luminescence switching of CdTe quantum dots in presence of water-soluble spironaphthoxazine

► The CdTe QDs containing a WSPO was used as the optical probe photoisomerization. ► The presence of WSPO could induce a fluorescence change of CdTe QDs. ► Reversible modulation of fluorescence intensity of CdTe QDs was achieved using UV-vis light.