Hybrid Nanomaterials for Biomedical Imaging and Cancer Therapy Wenbin Lin

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1 Hybrid anomaterials for Biomedical Imaging and Cancer Therapy Wenbin Lin Department of Chemistry University of orth Carolina Chapel Hill, C wlin@unc.edu

2 Magnetic Resonance Imaging Precontrast Post-contrast Measures MR signal of protons, mainly those of water Different concentrations in different tissues lead to contrast in the image T 1 weighted images show more intense signal where the longitudinal relaxation rate is fast (T 1 is short) Properties eeded for a Good Contrast Agent: Large spin number Slow electron relaxation Site for water coordination, and the ability to undergo fast water exchange with the solvent Slow rotational diffusion

3 T 1 -weighted MRI Contrast Agents High spatial Resolution o limit to penetration depth High soft tissue contrast Low sensitivity! Use of non-radiative contrast agents to increase MR signal intensity Free Gd 3+ TXIC! Relaxivity (T -1 1 vs [Gd]) r 1 ~ 4 mm -1 s -1 (3 T).1 to.2 mmol kg -1 7 to 1 g / 7 kg human

4 Why anoparticulate Contrast Agents? Sensitivity: Enhanced r 1 due to increased rotational correlation time increases S/ ratio decreases dose High Metal Payloads: Large particle r 1 increase in potential applications (e.g. targeting) Pharmacokinetics: Surface modification for longer circulation times increases S/ avoid RES and take advantage of EPR Target Specificity: taking advantage of over-expressed biological markers Artemov, D. J. Cellular Biochem. 23, 9, 518.

5 Targeted MR Contrast Artemov, D. J. Cellular Biochem. 23, 9, 518. Mulder et al. Bioconjugate Chem. 24, 15,

6 Fluorescently-Labeled MR-Enhancing Silica anoparticles = W = 15: 37 nm, ~1 Gd/particle 1 / T (1/s) Si-DTTA = trimethoxysilylpropyl diethylenetriaminetetraacetate R2: 6. mm-1 s-1 R1: 19.7 mm-1 s [Gd] (mm) R1 = ~4 1 5 mm -1 s -1 R2 = ~ mm -1 s -1

7 Monocyte Cell Labeling: LCFS and MRI Studies 4X 256 SS R2 256 FS % Viability [anoparticle] (ug/5 cells) Efficient nanoparticle uptake by monocyte cells (>98 %) Efficient cellular MR enhancement o cytotoxicity observed W.J. Rieter, J.S. Kim, K.M. L. Taylor, H. An, W. Lin, T. Tarrant, W. Lin, Angew. Chem. 27, 46,

8 Collagen Induced Arthritis (CIA): A Rheumatoid Arthritis (RA) Model A chronic, inflammatory, autoimmune disease that causes one s immune system to attack the joints. Loss of mobility due to pain and joint destruction. Infiltration of synovium by activated monocytes.

9 In Vivo ptical Detection + saline mg/kg P + 25 mg/kg P Control Arthritic

10 Luminescence Correlates to Clinical Index + saline mg P + 5. mg P.76, p= , p= , p=.17

11 Ex Vivo CIA Monocyte Labeling FITC P Merge T-Cells (CD3) +Collagen +P Monocytes (MMA) +Collagen + P Monocytes in the inflamed joint contain the Ps while T-cells, which are also implicated in rheumatoid arthritis, do not contain the Ps. Kim, J. S.; An, H.; Rieter, W. J.; Esserman, D.; Taylor, K. M. L.; Sartor, R. B.; Lin, W.; Lin, W.; Tarrant, T. K. Clin. Exp. Rheum., 29, 27, µm

12 MR Image Correlation to Fluorescence Pre-P 12h post-p 3D High-Res MRI Pre-P 12h post-p T1 T2 In Vivo Fluorescence

13 Layer-by-Layer Self-Assembly of Multifunctional anoparticles 1 PSS 1 Repeat P P1A P1B P2A + + H H Si Gd H 2 H 2 Gd-DTTA H 1 Gd H 2 H 9 n S PSS n H H S Gd H H 1a n [GdP-FITC] / [P] (ug/mg) 6 3 y = 1.772x x R 2 = Layer Kim, J.S.; Rieter,W.J.; Taylor, K.M.L.; An, H.; Lin, W.;Lin, W. J. Am. Chem. Soc. 27, 129, 8962.

14 How to Increase Gd Loadings w/o Sacrificing Relaxivities? Particle Diameter (nm) layer 3 layer 6 layer Layers of Gd-Polymer n+ R (1 5 s -1 ) Layer of [Gd-Polymer] n+

15 HT-29 Cell Targeting with RGD Peptides Control K7RGD LbL unfunctionalized K7GRD

16 In vitro Target-Specific MR Imaging of HT-29 Cancer Cell T1-weighted MR image o P GRD LbL P RGD LbL P Unfunctionalized LbL P

17 Mesoporous Silica anospheres as MRI Contrast Agents 2 µm Gd-Si-DTTA = Si Gd H 2 H y = 11.8x Weight % 9 7 1/T (sec -1 ) y = 65.5x y = 28.8x +.17 y = 1.2x Temperature ( C) Concentration (mm)

18 J. Am. Chem. Soc. 28, 13, Mesoporous Silica anospheres for Multimodal in vivo Imaging 2.1 µmol/kg 31 µmol/kg

19 Degradable MS-Gd anoparticles = MS-Gd = MS-Gd-1 cleaved from MS-Gd-1 and cleared from kidney in vivo 1/T (s-1) y = x R 2 =.9983 y = x R 2 = [Gd] (mm) % Released Time (hours) Release profile in the presence of 1 mm cysteine at 37 C

20 Biodegradable Hydrogel anoparticles umber % Size (nm) Water EtH 3L EtH 3L Water nm T 1 -Weighted % release A B C Time (hr) Release profile in the presence of 1 mm cysteine at 37 C

21 Manganese anoscale Metal-organic Frameworks Thin Coating Thick Coating Weight % Silica Coated (9147) PVP Coated (9145B) Uncoated anorods (4115) Thicker silica coated (9148) Temperature ( C) PVP TES 2 2 H H Si Et H H Et Et = H H = H H H H 2 H H S H C 2 H JACS, 28, 13, Cl Et Si Et Et

22 Silica-Coated Mn MFs for Multimodal Imaging Pre-contrast ~13 minutes after injection ~65 minutes after injection

23 Iodinated MFs for CT Imaging I-MF Iodixanol % dissolved dekrafft, Angew. Chem., in revision. time (h)

24 Targeted Delivery of Anticancer Drug-Containing anoparticles H 3 H 3 A Pt A Cl Cl 2e- H 3 Cl Pt H 3 Cl DA binding Cell death Poor Solvent a) PVP b) TES CP-1 CP-1 = = Tb 3+ = c(rgdfk) 5 nm 5 nm Rieter, W.J.; Pott, K.M.; Taylor, K.M.L.; Lin, W. J. Am. Chem. Soc., 28, 13,

25 We have also shown that the cytotoxicity of these particles can be enhanced by conjugating with targeting molecules. MFs with Large Payloads of Platinum Anticancer Drugs % Released CP-1 CP-1'-a CP-1'-b Time (h) % Survival Cisplatin DSCP CP-1 CP-1'-a+c(RGDfK) CP-1'-b+c(RGDfK) [Pt] (µm) Preliminary inhibitory assays show that MFs are very effective in killing HT-29 human colon cancer cells in vitro.

26 Post-Synthetic Modifications of MIL-11 anoparticles for Targeted Delivery of Cisplatin and ptical Contrast Agents a) b) c) d) e) f) Taylor-Pashow, K.M.L.; Della Rocca, J.; Xie, Z.; Tran, S.; Lin, W. J. Am. Chem. Soc. 29, 131,

27 Joe Della Rocca Kathryn dekrafft Wave Wang Demin Chen Caleb Kent Joe Falkowski Rachel Huxford Anna Dunn Dr. Sam Ma Dr. Zhigang Xie Dr. Feijie Song Dr. Min Zhang Acknowledgements Collaborators Terri Tarrant, MD Arthritis Center Weili Lin, Ph.D. Radiology tto Zhou, Ph.D. Physics Dr. William Rieter Dr. Jason S. Kim Dr. Kathryn Taylor Kimberly Pott Christie koruwa Athena Jin Sylvie Tran March 28 ational Science Foundation (CHE and DMR) ational Institutes of Health (CI ) UC Cancer Research Fund DARPA DE