Supporting Information for Photoswitchable micelles for the control of singlet-oxygen generation in photodynamic therapies Yan Zhai, Henk J. Busscher,,* Yong Liu, Zhenkun Zhang, Theo G. van Kooten, Linzhu Su, Yumin Zhang, Jinjian Liu, Jianfeng Liu, Yingli An, Linqi Shi,, * State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin 300071, China University of Groningen and University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Science & Peking Union Medical College, Tianjin, 300192, P.R. China Email address: shilinqi@nankai.edu.cn * Corresponding author: University of Groningen and University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands Email address: h.j.busscher@umcg.nl
Scheme S1. Synthesis route of BDTE.
Scheme S2. Synthetic route of PEG-b-PCL.
Table S1. Cumulative percentage release of ZnTPP or BDTE from different micelles suspended for 72 h in 14 ml PBS (ph = 7.4) (3 mg/ml) after 72 h. Micelles were loaded with 10 or 100 µg ZnTPP or BDTE alone per mg micelles, respectively or 10 µg ZnTPP per mg micelles with corresponding amounts of BDTE in ZnTPP/BDTE 1 and ZnTPP/BDTE 20 micelles. Cumulative release (%) ZnTPP BDTE ZnTPP/BDTE 1 micelle ZnTPP/BDTE 20 micelle ZnTPP 2.7 -- 3.3 4.8 BDTE -- 2.7 3.0 3.7
(a) (b)
(c) Figure S1. NMR spectra of BDTE and intermediate products obtained during its synthesis. (a) 1 H NMR spectra (400 MHz, 298 K) of 1,5-Bis-3-(2-chloro-5-dimethylthienyl)-1,5- pentadione. (b) 1 H NMR spectra (400 MHz, 298 K) of 1,2-bis(5-chloro-2-methylthiophen-3- yl)cyclopent-1-ene. (c) 1 H NMR spectra (400 MHz, 298 K) of BDTE. All NMR spectra were taken on a Bruker AVANCE II (Karlsruhe, Germany) and compounds were dissolved in CDCl3.
Figure S2. ESI mass spectrum of BDTE. High resolution electrospray ionization mass spectrum, obtained using a Varian 7.0T FTMS (California, USA) The mass to charge ratio (m/z) was measured to be 415.1299, consistent with the calculated value of 415.1297 based on the molecular composition of C26H22N2S2 [M+H]+.
Figure S3. 1 H NMR spectra of PEG-b-PCL copolymer in CDCl 3. Nuclear magnetic resonance (NMR) spectrum (400 MHz, 298 K) was recorded on Bruker AVANCE II (Karlsruhe, Germany).
Figure S4. UV/Vis spectroscopy to yield calibration curves for the calculation of the actual ratio of ZnTPP and BDTE from their initial feeding ratio during preparation. (a) UV/Vis spectra of BDTE at various concentrations in DMF. (b) Calibration curve, i.e. the UV/Vis absorbance at 281 nm as a function of the concentration of BDTE in DMF. (c) UV/Vis spectra of ZnTPP at various concentrations in DMF. (d) Calibration curve, i.e. the UV/Vis absorbance at 425 nm as a function of the concentration of ZnTPP in DMF. 9
Figure S5. Micellar diameters of PEG-b-PCL micelles as a function of time in water. (a) Colloidal stability of ZnTPP and BDTE loaded micelles. (b) Colloidal stability of ZnTPP/BDTE X micelles. Data are means over three independent experiments, with error bars indicating standard deviations. 10
Figure S6. Evaluation of the 1 O 2 generation ability of ZnTPP/BDTE X micelles by singlet oxygen sensor green (SOSG). Fluorescence change (I/I 0 at 525 nm) of SOSG in different ZnTPP/BDTE X micelles (1 µm ZnTPP) during irradiation with 405 nm laser light (8 mw/cm 2 ) to initiate singlet-oxygen generation in a cycle of closing (308 nm) and re-opening (Vis > 450 nm, long-wavelength, pass-filtered Xe-light) of the photoswitches. (a) Micelles suspended in water. (b) Micelles suspended in PBS. SOSG exhibits weak blue fluorescence, while in the presence of singlet-oxygen, it emits a green fluorescence (excitation/emission maxima ~504/525). A stock solution of 0.5 mm SOSG in DMSO was prepared. 10 µl of SOSG in DMSO (0.5 mm) was added to 1 ml of different micelle suspensions (0.1 mg/ml). SOSG was excited at 504 nm and the emission was read at 525 nm. 11