Supporting Information Synergistic Anticancer Potential of Artemisinin When Loaded with 8- Hydroxyquinoline-Surface Complexed-Zinc Ferrite Magnetofluorescent Nanoparticles and Albumin Composite Uday Narayan Pan, Pallab Sanpui, Anumita Paul * and Arun Chattopadhyay * Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India. Department of Biotechnology, BITS Pilani, Dubai Campus, P O Box 345055, Dubai International Academic City, Dubai, UAE. Centre for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India. *E-mail: arun@iitg.ac.in; *E-mail: anumita@iitg.ac.in S-1
Experimental section: Materials: Artemisinin, iron chloride hexahydrate (FeCl3.6H2O), trioctylphosphine oxide (TOPO), 1-octadecene, sodium oleate and fluorescein isothiocyanate isomer I were purchased from Sigma Aldrich. 8-Hydroxyquinoline, zinc chloride (ZnCl2), bovine serum albumin (BSA), oleic acid, and hexane were procured from Merck, India. 3-(4,5-dimethylthiazol-2- yl)-2,5-diphenyltetrazolium bromide (MTT) and ethanol were obtained from Himedia, India and Tedia USA, respectively. All chemicals were used without further purification. Milli-Q grade water was used in all the experiments. Instruments: Transmission electron microscopic images, high resolution transmission electron microscopic images (HR-TEM) and selected area electron diffraction (SAED) patterns and energy-dispersive X-ray spectrum (EDX) were obtained using JEOL JEM 2100F TEM at 200 KV. Nanoparticle dispersions of appropriate concentration were drop-cast on a carbon-coated copper grid, then dried and visualized under TEM. HR-TEM and SAED images were further analyzed using Gatan Digital Micrograph software to find out lattice fringes. Hitachi U-2900 UV-vis spectrophotometer was used for recording uv-vis absorbance spectra. PL emission and excitation were recorded using HORIBA FluoroMax-4 instrument. Powder XRD pattern of ZnFe2O4 NPs and other samples were recorded using Rigaku TTRAX III X-ray diffractometer. Magnetic measurements to obtain hysteresis loop and saturation magnetization were performed using 7410 series vibrating sample magnetometer. Carl Zeiss confocal LSM 880 was used to obtain fluorescence image of cells. Nikon Coolpix L810 camera was used to acquire digital photographs. Preparation of Zinc ferrite nanoparticles (ZnFe2O4 NPs): ZnFe2O4 NPs were synthesized in two steps. In the first step, a mixture of zinc oleate and iron oleate at 1:2 ratio was prepared. For that, 26.8 mmol of FeCl3.6H2O, 13.4 mmol of ZnCl2 and 36.5 g of sodium oleate were dissolved in 3:4:7 water, ethanol and hexane mixture and refluxed for 4 h at 70 o C. A brown S-2
color mixture of 1:2 Zn-oleate and Fe-oleate complexes was separated from upper hexane layer, then washed with water:ethanol mixture for five times, dried and kept for further use. In the second step 300 mg of 1:2 Zn-oleate and Fe-oleate complex mixture, 50 L of oleic acid and 25 mg of TOPO were added in 10 ml of 1-octadecene and heated at 120 C under reflux for 1 h. Then temperature was raised to 200 C and N2 gas were purged through it. Once N2 purging was completed temperature was again raised to 310 C and kept at this temperature for 2 h in order to complete the synthesis of ZnFe2O4 NPs. On completion of reaction, ZnFe2O4 NPs were washed with ethanol:hexane mixture and magnetically separated with the cycle being completed for five times to remove excess reactants and then redispersed in 50 ml of hexane and stored for further use. 1 Preparation of HQ-ZFNPs@BSA: First 2 ml of the stock ZnFe2O4 NPs dispersion was diluted to 10 ml using hexane. For surface complexation, 50 µl of the 10 mm ethanolic solution of HQ was added to it under sonication. Complexation reaction happened immediately after addition of HQ. Surface complexed ZnFe2O4 NPs (HQ-ZFNPs) were separated using magnet and then washed with ethanol:hexane mixture and redispersed in 1% aqueous BSA solution under strong sonication for 2 h. Aqueous dispersion of HQ- ZFNPs@BSA was further separated with magnet and washed with 1% BSA solution for two times and finally dispersed in 1% aqueous BSA solution and kept at 4 C. Loading of Artemisinin (ART): To load ART into HQ-ZFNPs@BSA, first 2 ml of the stock ZnFe2O4 NPs dispersion was diluted to 10 ml using hexane and then 50 µl of 10 mm ethanolic solution of HQ was added to it under sonication for complexation. Once the complexation was over HQ-ZFNPs were separated using powerful neodymium magnet and a mixture of 2 ml of 1% BSA solution and 50 µl of 5 mg/ml ART was added and sonicated for 2 h. ART loaded HQ-ZFNPs@BSA was separated and washed following centrifugation. S-3
Encapsulation efficiency of artemisinin was calculated by determining the amount of ART present on the supernatant and comparing it with the amount of ART was initially added. To calculate the amount of ART present on supernatant a NaOH based spectrophotometric estimation method of ART was used. 1,2 A standard curve was also produced by mixing different amount of ART in the supernatant of HQ-ZFNPs@BSA followed by measuring the absorbance following the same NaOH based estimation method. 2 Supernatant of HQ- ZFNPs@BSA was taken as solvent to dilute ART-solutions to avoid influence of ph and other materials present in the supernatant, on the absorbance during estimation process. 3,4 The following formula was used to calculate the encapsulation efficiency, Encapsulation efficiency (%)= {( Cadd - Csup) / Cadd } 100 Where Cadd is concentration of ART originally added and Csup is concentration of ART present in the supernatant after pelleting down the ART loaded HQ-ZFNPs@BSA. Photostability: Photostabilities of aqueous dispersions of HQ-ZFNs@BSA and ethanolic solution of FITC were measured in HORIBA JobinYvon FluoroMax-4 spectrofluorimeter. Data were recorded under constant irradiation of 365 nm up to 1800 s at an interval of 0.1 s. Cell viability assay: HeLa, HepG2, A375, HEK, L132 and 3T3 cells were acquired from NCCS, Pune, India. Cell culture medium was prepared by mixing 10% (v/v) fetal bovine serum (FBS) and Penicillin- Streptomycin (100 U ml 1) with Dulbecco s modified Eagle s medium (DMEM) under incubation at 37 C and 5% CO2. MTT-based cell viability assay was performed in 96-wells plate with 10,000 cells. Cells were treated with different concentrations of different (as appropriate) materials for 24 h. For MTT assay, absorbance of the Fromazane was measured using Bio-Rad 680 microplate reader and cell viability calculated using the following formula: Cell Viability (%)= { S-4 A (T) A (C) } 100....(1)
Here A(T) absorbance of Fromazane in the treated sample, A(C) absorbance of Fromazane in non-treated control sample. Combination indices were calculated using CompuSyn software. Sample preparation for CLSM imaging: Cells were grown on a cover slip and treated with 100 µg/ml of HQ-ZFNs@BSA for 2 h. After treatment, cells were fixed with formaldehyde and chilled ethanol and mounted on a glass slide using glycerol. Images were taken in Carl Zeiss LSM 880 microscope with 355 laser excitation. To show the presence of HQ-ZFNPs@BSA inside lysosome, HeLa cells were treated with a mixture of HQ-ZFNPs@BSA and Red DND-99 LysoTracker for 2h and then images were taken under 365 and 561 laser excitations. Magnetically targeted imaging: In a 60 mm petri dish two coverslips were positioned at maximum distance to each other and HeLa cells were grown on them for overnight. Next, a powerful neodymium magnet was placed at the bottom of only one coverslip. Then, 100 µm/ml HQ-ZFNs@BSA was added to the petri-dish and kept for 2 h. Cells were then fixed using formaldehyde and ethanol and images were taken in Carl Zeiss LSM 880 microscope. S-5
Figure S1: (A-B) TEM images and (C) size distribution (calculated from 50 NPs) of ZFNPs. Figure S2: Powder XRD pattern of (a) HQ-ZFNPs and (b) ZFNPs showing characteristic peaks at 2θ of 29.7, 35.4, 43.0, 53.5, 56.8, 62.4 and 74.0, corresponding to (220), (311), (400), (422), (511), (440) and (533) planes, respectively, S-6
Figure S3: FTIR spectra of (a) HQ-ZFNPs, (b) ZFNPs and (c) HQ. S-7
Figure S4: (A-B) TEM images, (C) SAED pattern, (D) HR-TEM image and (E) corresponding IFFT pattern, and (F) size distribution of HQ-ZFNPs@BSA. KeV Figure S5: EDX spectrum of HQ-ZFNPs@BSA displaying the presence of iron and zinc. S-8
Figure S6: (A) Size-distribution of HQ-ZFNPs@BSA dispersed in water as measured by DLS. (B) Zeta potential distribution of aqueous dispersion of HQ-ZFNPs@BSA at physiological ph. S-9
Figure S7: Digital images of ZnFe2O4 NPs and HQ under day light or UV light and in presence or absence of magnet. S-10
Figure S8: UV-vis spectra of (A) aqueous solution of BSA and (B) powdered HQ-ZFNPs. Emission spectra of (C) aqueous solution of BSA with excitation at 278 nm (λem=345 nm) and (D) powdered HQ-ZFNPs with excitation at 365 nm (λem=518 nm). Digital images of (E1) HQ-ZFNPs powdres inside cuvette showing strong green emission and (E2) BSA powder under 365 nm UV light. S-11
Figure S9: Excitation spectrum of HQ-ZFNPs@BSA. The emission maximum was set at 503 nm. Figure S10: Time-resolved photoluminescence spectrum of HQ-ZFNPs@BSA. S-12
Figure S11: Stability of HQ-ZFNPs@BSA in human blood serum measured in terms of fluorescence emission intensity. S-13
Figure S12: CLSM Z-staking images of different cell lines showing internalization of HQ- ZFNPs@BSA. S-14
Figure S13: CLSM images of control cells taken in similar sets of conditions as treated one. Table S1: Combination indices of ART-loaded HQ-ZFNPs@BSA in different cell line. S-15
Figure S14: Isobologram plots showing synergistic effect of ART loaded HQ-ZFNPs@BSA in HeLa, A375 and HePG2 cells. S-16
Figure S15. CLSM images of HeLa cells treated with HQ-ZFNPs@BSA (A) in presence and (B) in absence of sodium azide (0.1%). (C) PL emission intensity plot calculated from image A and B, showing 89% decrease in PL emission intensity in A compared to B due to presence of known endocytosis inhibitor sodium azide. Indicating endocytosis as the preferred way of uptake of HQ-ZFNPs@BSA by HeLa cells. S-17
Figure S16. CLSM Images of HeLa cells showing co-localization of HQ-ZFNPs@BSA with LysoTracker-labeled lysosomes. S-18
Referances: 1. Pan, U. N.; Sanpui, P.; Paul, A.; Chattopadhyay, A. Surface-Complexed Zinc Ferrite Magnetofluorescent Nanoparticles for Killing Cancer Cells and Single-Particle-Level Cellular Imaging ACS Appl. Nano Mater 2018, 1, 2496-2502. DOI: 10.1021/acsanm.8b00545 2. A. Bharati, S.C. Sabat A Spectrophotometric Assay for Quantification of Artemisinin Talanta, 82, 2010, 1033-1037. 3. Pan, U.N.; Khandelia, R.; Sanpui, P.; Das, S.; Paul, A.; Chattopadhyay, A. Protein- Based Multifunctional Nanocarriers for Imaging, Photothermal Therapy and Anticancer Drug Delivery ACS Appl. Mater. Interfaces 2017, 9, 19495 19501. 4. Khandelia, R.; Bhandari, S.; Pan, U. N.; Ghosh, S. S.; Chattopadhyay, A. Gold Nanocluster Embedded Albumin Nanoparticles for Two-Photon Imaging of Cancer Cells Accompanying Drug Delivery Small 2015,11, 4075 4081 DOI: 10.1002/smll.201500216 S-19