Photodynamic Therapy, Optical Trapping and Photostimulated Emission Using Upconverting Nanoparticles

Transcription

1 Photodynamic Therapy, Optical Trapping and Photostimulated Emission Using Upconverting Nanoparticles John A. Capobianco Department of Chemistry Biochemistry, Centre for NanoScience Research, Concordia University, Montreal, Canada

2 Nanostructures in biology Nanometer scale interesting in biological systems, proteins are 10 s of nanometer in size Allows to probe and modify biological systems Nanostructures have been proposed/used for: drug delivery labelling agents sensors optical imaging nanothermometry MRI Photodynamic Therapy

3 Lanthanide doped Nanoparticles Attractive features: Stability with respect to photobleaching Long photoluminescence lifetime Low toxicity Sharp f-f absorption and emission peaks Flexibility in surface chemistry Small size - optical properties not sensitive to size Emission colour may be tuned More importantly, they can undergo a process known as upconversion J. C. Boyer, F. Vetrone, L. A. Cuccia, J. A. Capobianco, J. Am. Chem. Soc., (2006), 128, F. Wang, X. Liu, J. Am. Chem. Soc., (2008), 130,

4 Upconversion Upconversion is a non-linear anti-stokes process that efficiently converts two or more low-energy excitation photons, which are generally near infrared (NIR) light, into a higher energy outcome photon (e.g., NIR, visible, ultraviolet) through the use of long lifetime and real ladder-like energy levels of trivalent lanthanide ions embedded in an appropriate inorganic host lattice. Excited State Absorption Energy Transfer Upconversion E 2 E 2 hν E 1 E 1 E 1 hν hν hν G G G Ion 1 Ion 1 Acceptor Ion 2 Donor 4

5 Ln 3+ -Doped Fluoride Nanoparticles 20 nm Thermal decomposition synthesis of fluoride NPs (NaY(Gd)F 4, LiYF 4 ) yields hydrophobic and monodisperse nanoparticles Particle size and morphology can be tailored by varying reaction conditions (time, temperature) Solvothermal synthesis yields water dispersible nanoparticles ~20-30 nm in size JACS, 2006, 2006, 128, , Nano Lett., 2007, 7, , Chem. Mater., 2009, 21, , Adv. Mater., 2009, 21, , Adv. Funct. Mater., 2009, 19,

6 Photodynamic Therapy

7 Targeting,Therapeutic and Imaging Cancer Cells Targeting ligand Photosensitizer Receptor Cancer Cell Excitation NIR excitation used to excite upconverting nanoparticles less harmful to cells NIR light has greater tissue penetration depth and eliminates autofluoresence Targeting, Imaging and Therapeutics A nanoparticle bearing a recognition ligand and a therapeutic agent is introduced into a biological system Targeting ligand specifically recognizes a receptor site on a cancer cell The nanoparticle is taken up in the cell by endocytosis NIR light will excite the lanthanide nanoparticle, which will emit light. This light is absorbed by the photosensitizer, which generates singlet oxygen cell death

8 Photodynamic Therapy (PDT) Photosensitizer PDT Drug administration Light Oxygen Light exposure and cell injury

9 2 nd Generation - Temoporfin Soret Band Q Bands Temoporfin, Foscan, or 5,10,15,20-tetra(m-hydroxyphenyl)chlorin (m-thpc) Structurally distinct compounds, late 1980s High chemical purity and strong long-wavelength absorption Low dose of 0.15 mg/kg

10 Fluorescence Resonance Energy Transfer Blue upconversion emission from LiYF 4 : Tm 3+ /Yb 3+ UCNP The FRET Spectral Overlap Integral Overlap between donor emission and acceptor absorption Donor and acceptor must be in close proximity (1-10 nm) Product-Highlights/Fluorescence-Resonance-Energy-Transfer-FRET.html Accessed date: 05/02/2013

11 LiYF 4 :Tm 3+ /Yb 3+ -m-thpc Construct

12 Modification of Temoporfin

13 Mass Spectrometry Purified products m-thpc 15.4% m-thpc-mba 58.3% m-thcp-2mba 15.2% m-thcp-3mba 11.1% m-thcp-4mba 0

14 Mass Spectrometry

15 UV/Vis Absorption UV/Vis absorption spectra of ( ) m-thpc, m-thpc-mba isomers eluted at ( ) 7.5 min and ( ) 10.1 min from Prep LC-MS.

16 Energy Transfer Process I - presence of the acceptor I o - absence of the acceptor Energy transfer efficiency: ~ 33% E = 1 I/I o,

17 Generation of Singlet Oxygen Absorption spectra of a solution of DPBF and UCNP-m-THPC-MBA (1 mg/ml) Irradiation: 980 nm Pseudo 1 st order rate constant: k=4.75x10-3 min -1

18 Cell Viability of HeLa Cells Incubation time: 4 hrs Irradiation source: 980 nm Irradiation time: 1 hr

19 Computational Method Gaussian 09 Program B3LPY/ 6-31G, Geometry optimization UV/Vis spectrum Molecular orbitals

20 Temoporfin (m-thpc) UV/Vis spectrum calculated in liquid phase using EtOH as solvent

21 m-thpc-mba(i) UV/Vis spectrum calculated in liquid phase using EtOH as solvent

22 m-thpc-mba(ii) UV/Vis spectrum calculated in liquid phase using EtOH as solvent

23 m-thpc-mba(iii) UV/Vis spectrum calculated in liquid phase using EtOH as solvent

24 Influence of Linkers on m-thpc Computational Results 1. UV/Vis spectrum of m- THPC-MBA(I) and (II) showed no difference compared to m-thpc 2. m-thpc-mba(iii) resulted in a red-shift of the Soret band, as well as a decrease in absorption coefficient

25 Challenges of trapping small particles Detecting trapped particles Trapped NPs are usually evidenced from scattering measurements Scattering is expected to be weak for optically trapped UCNPs in water because of Low refractive index contrast Low scattering of IR light

26 Optical trapping set-up CCD Trapping beam 2 photon emission 100X 0.8NA UCNPs solution

27 Trapping demonstration [UCNPs] = cm -3 in water 0 s 40 s 80 s 100 s 140 s

28 NIR Photo-stimulated Nanophosphor TRAPPING Eu 2+ UV Excitation Dy 3+ Eu 2+ DE-TRAPPING NIR Excitation Eu nm Dy 3+ Eu 2+

29 Optical Properties CaS:Eu 2+ (0.02 %mol)/ Dy 3+ (X %mol) Intrinsic Defects λ exc = 312 nm Dy 3+ Transition 4 F 9/2 6 H 13/2 Eu 2+ Transition 4f 6 5d 4f 7 Dy 3+ Transition 4 F 9/2 6 H 9/2 D.C. Rodríguez-Burbano., E. Martín-Rodríguez., P. Dorembos., M. Bettinelli., J.A. Capobianco. J. Mater. Chem C., XX (XXXX) p XX XX. (Accepted)

30 Intrinsic Defects: Undoped CaS Ca 2+ (100 pm) λ exc = 312 nm Na + (102 pm) K + (138 pm) Less formation of defects sites D.C. Rodríguez-Burbano., E. Martín-Rodríguez., P. Dorembos., M. Bettinelli., J.A. Capobianco. J. Mater. Chem C., XX (XXXX) p XX XX. (Accepted)

31 CaS:Dy 3+ (X% mol) λ exc = 312 nm λ exc = 312 nm 4 F 9/2 6 H 15/2 4 F 9/2 6 H 13/2 4 F 9/2 6 H 13/2 Na 2 S (Precursor) K 2 S (Precursor)

32 Photo-stimulation using 980 nm 4 f 6 5d D.C. Rodríguez-Burbano., E. Martín-Rodríguez., P. Dorembos., M. Bettinelli., J.A. Capobianco. J. Mater. Chem C., XX (XXXX) p XX XX. (Accepted)

33 PHOTO-CONTROL OF BIOMOLECULES UV UV Vis Bis-AzoPC DPPC: 1,2-dipalmitoyl-sn-glycero-3-phosphocholine Bandarab H.M.D., Burdette S.C., Chem. Soc. Rev., (2012), 41, Beharry, A.A., Woolley, G.A., Chem. Soc. Rev., (2011), 40, Morgan, C.G.,Bisby, R.H., Johnson, S.H., Mitchell, A.C., FEBS Letters., (1995) 375,

34 AZOBENZENE PHOTOSWITCHING MOLECULE 314 nm π-π* trans cis 250 nm 280 nm 440 nm 450 nm n-π* Beharry, A.A., Woolley, G.A., Chem. Soc. Rev., (2011), 40,

35 AZOBENZENE PHOTOSWITCHING USING UCNP UV 4-(Phenylazo)benzoate LiYF 4 : Tm 3+ /Yb 3+

36 AZOBENZENE PHOTOSWITCHING USING UCNP UV 4-(Phenylazo)benzoate LiYF 4 : Tm 3+ /Yb 3+

37 FLUORESCENCE RESONANCE ENERGY TRANSFER (FRET) λ EXC : 980 nm AzoPhenoxyCOO - : 9-[(4-Phenylazo)-phenoxy]-nonan-1-oxy

38 FLUORESCENCE RESONANCE ENERGY TRANSFER λ EXC : 980 nm ET UV: 51% ET UV: 36% Li-UCNP: LiYF 4 :Tm 3+ /Yb 3+ AzoPhenoxyCOO - : 9-[(4-phenylazo)-phenoxy]-nonan-1-oxy OAF: Oleic acid free

39 PHOTOSWITCHABLE LIPOSOMES CONTROLLED BY UCNP UV LiYF 4 -UCNP Phosphate Dye Azobenzene

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42 Molecular Orbitals Calculated molecular orbitals (from bottom to top, HOMO -1 through LUMO +1) for m-thpc, m-thpc- MBA(I), m-thpc-mba(ii), and m- THPC-MBA(III), from left to right. The electron density is shown as the balloons in red (positive wavefunction) and green (negative wavefunction).