Surface Engineering of g-maghemite (Fe 2 O 3 ) Nanoparticles Process Optimization Using Design Of Experiments (DoE) for sirna-mediated Gene Silencing

Transcription

1 Surface Engineering of g-maghemite (Fe 2 O 3 ) Nanoparticles Process Optimization Using Design Of Experiments (DoE) for sirna-mediated Gene Silencing Prof. J.-P. Lellouche (Dpt of Chem. BIU & BINA) Profs. S. Michaeli & Ron S. Kenett (BINA & KPA Ltd. on-going cooperation) Liron L. Israel & Emmanuel Lellouche (PhD students) $$$$ VII th European Project SaveMe (grant agreement n ) (FP7-NMP LARGE-4 area - Large Collaborative Projects) & Israeli Ministry of Trade & Industry KAMIN/RIMONIM (Magnet project) funding Bar-Ilan University, Dpt of Chemistry, Nanomaterials Research Center, Institute of Nanotechnology & Advanced Materials (BINA) Ramat Gan, Israel Phone: , Fax: , lellouj@biu.ac.il & jp.m.lellouche@gmail.com

2 # Ultra-small [CeL n ] 3/4+ cation/complex-doped g-fe 2 O 3 NPs (fabrication & selected characterization features) # Anti-aggregation & [CeL n ] 3/4+ cation/complex-mediated properties of corresponding ultra-small hydrophilic NPs Coordinative attachment chemistry of organic species (25kDa b-pei polymer) # Global DoE-driven optimization of the [CeL n ] 3/4+ cation/complex doping step # Gene silencing experiments (sirna delivery) & selected NP/composite toxicity

3 Ultra-Small CAN-maghemite (CAN- -Fe 2 O 3 ) NPs - Fabrication Process Data New nanofabrication conditions = Hydrophilic ultra-small maghemite ( -Fe 2 O 3 ) NPs (mono-electronic CAN oxidant-mediated ultrasound-assisted processing) Absolute NP aggregation control (charge control): Neither use of any surfacepassivating bifunctional ligand nor physically adsorbed natural/non-natural polymer Pre-formed Massart magnetite (Fe 3 O 4 ) nanoparticles (NPs) CAN [Ce(IV)(NH 4 ) 2 (NO 3 ) 6 ], MeCOMe/EtOH, C, 0.5-1h, high power ultrasonication Ce 3/4+ cation doping of the NP surface = Inorganic method for NP aggregation control Ce 3/4+ cation-stabilized maghemite NPs (CAN- g-fe 2 O 3 NPs) Fe(III) atom Fe Fe Fe O(H) NP Fe core Fe Fe Fe O(H) Fe [CeL n ] 3/4+ Doping Ce 3/4+ metal cation/complex L L L Ce L L L 3/4 + [CeL n [ 3/4+ -based coordination chemistry L: Coordinating monodentate/ polydentate ligand (OH, H 2 O, O-N(=O)-O, R-NH 2 and/or R-NH-linker-NH-R' (PEI) ligands) CAN

4 Ultra-Small CAN-maghemite (CAN- -Fe 2 O 3 ) NPs Selected Characterization Data Ce element/[celn] 3/4+ complexes: Very low level of Ce (NP surface - ICP-AES: Ce/Fe wt/wt ratio = 0.029, Ce/Fe molar ratio = ) XRD & XPS features Compatible with a crystalline -Fe 2 O 3 phase Ultra-small nm-sized (TEM) positively charged (z potential: mv) NPs: Ce 3d 5/2 - BE = ev)

5 HR-TEM/Compositional EDAX Analysis = Presence of the Ce element (0.24% weight/0.02% atom)

6 Super-paramagnetic NPs Saturation Ms: 75.2 emu/g & blocking T C: C

7 Ultra-Small CAN-maghemite (CAN- -Fe 2 O 3 ) NPs MRI Relaxivity Data (Bioimage Ltd. MRI Research & Consulting) Clinically approved SPIONs: Ferumoxides (Feridex/Endorem, r 1 /r 2 relaxivites: 23.9 & 98.3 mm - 1 sec -1 ) at a particle size of nm, & Ferucarbotran (Resovist, r 1 /r 2 relaxivites: 25.4 & mm -1 sec -1 respectively) at a particle size 60 nm Main effect of SPION particles on T 2 * relaxation = MRI usually performed using T 2 /T2*-weighted sequences Wang YX. Superparamagnetic iron oxide based MRI contrast agents: Current status of clinical application. Quant Imaging Med Surg 2011;1: DOI: /j.issn Bioimage Ltd. MRI Research & Consulting CAN- -Fe 2 O 3 NPs: r 1 : & r 2 : 189 mm -1 sec -1

8 Ultra-Small CAN-maghemite (CAN- -Fe 2 O 3 ) NPs [CeL n ] 3/4+ cation/complex-mediated NP functionalization/significance = Design of Experiment - Driven Global Doping Process Optimization Fe FeO(H) Fe CAN-g-Fe 2 O 3 NPs [CeL n ] 3/4+ L L L Ce L L L 3/4+ L: Coordinating ligand (OH, H 2 O, O-N(=O)-O, R- NH 2 and/or R-NH-linker-NH-R' (PEI) ligands) kda PEI Aq. H 2 O 2, 10 C, overnight 3. RNA complexation NP RNA-loaded PEI 25-ox -CAN-g-Fe 2 O 3 NPs CAN oxidant = Dual role: Fe 3 O 4 phase oxidant & elemental Ce donor Unusual highly positive NP z potential/surface charge due to [CeL n ] 3/4+ cation/cpx doping even at a so low level - Ce/Fe wt/wt ratio = 0.029, Ce/Fe molar ratio = Innovative way of NP decoration chemistry: [CeL n ] 3/4+ cations/complexes acting as very strong Lewis Acid centers together with corresponding lanthanide coordination capability of any Lewis base N/O/S-containing organic species (ccordination attachment of polymers, small ligands, peptides, oligosaccharides, antibodies, & more Experimental Design of Experiments (DoE) for doping process global optimization (opti- Mization of selected NP physico-chemical features)

9 CAN DOE -maghemite (CAN DOE - -Fe 2 O 3 ) NPs: Design of Experiment (DoE) methodology for globally optimized USassisted doping process: 4 main factors set-up at both low & high value levels # Ageing time of starting Fe 3 O 4 (magnetite) NPs # CAN oxidant amount # MeCOMe solvent value (v/v 1/1mixture MeCOMe/ddH 2 O) # High-power US time (power modulator: 25%) = Four factor two-level full factorial design (MINITAB 16 DoE software - version , Minitab Inc.) with one factor replicate (corner points) & center points = Table of 17 experiments ( center point 1 block) Ageing time [h] CAN oxidant [mg] MeCOMe volume [ml] Reaction time [h] DLS [nm] ξ Potential [mv] Wt Ce/Fe ratio NP Size [TEM, nm]

10 CAN DOE -maghemite (CAN DOE - -Fe 2 O 3 ) NPs Data analysis of critical factors influence Most influential factor: CAN amount Entry 3: Ce doping increase by a 266.1% factor!!! All other factors & 2 nd /3 rd order standardized effects found less influential/significant Highest w/w Ce/Fe ratios for 6.0 ml MeCOMe & CAN amount(s) >> mg

11 CAN DOE - -Fe 2 O 3 NPs Data analysis of critical factors influence Smallest (TEM) NPs ( nm) obtained for similarly high amounts/volume of CAN & MeCOMe components Same conditions also provided NP highest z potenvalues ( mv) & smallest hydrodynamic diameters (40-50 nm range) CAN oxidant [mg] Contour Plot of potential [mv] vs CAN oxidant [mg], acetone [ml] potential [mv] < > 55 CAN oxidant [mg] CAN oxidant [mg] Contour Plot of Size/TEM vs CAN oxidant [mg], acetone [ml] acetone [ml] Contour Plot of DLS [nm] vs CAN oxidant [mg], acetone [ml] Size/TEM < > 8.00 DLS [nm] < > acetone [ml] acetone [ml]

12 CAN DOE - -Fe 2 O 3 NPs Data analysis of critical factors influence Two-way interaction plot graphs: analysis of the way the different factors interact & influence process response(s) Two-way Interaction plot graphs = Both US time & MeCOMe volume show significant intercations for z potential & NP (TEM) size responses

13 CAN DOE - -Fe 2 O 3 NPs Use of the MINITAB 16 software profile optimizer tool Software optimizer tool = takes under consideration differently important responses with predictive capabilities for given designed conditions # Proposed optimal conditions: 4.22h ageing time (Fe 3 O 4 NPs), mg CAN, 6.0 ml MeCOMe, & 0.5 high-power US Blue values for calculated responses # Experimentally DoE Tool obtained values: nm (DLS), z potential: mv, w/w Ce/Fe ratio: (even higher than the Tool calculated value), & 6.61±2.04 nm NP diameter

14 CAN DOE - -Fe 2 O 3 NPs Use of the MINITAB 16 software profile optimizer tool (Selected Physico-Chemical Characterization Data) Hydrodynamic NP Ø: 60.00± 1.98 nm potential: +45.7±1.88 mv ICP-AES elemental analysis: wt/wt Ce/Fe ratio = (60.5% higher than software prediction) x 3.5 fold!! the value found for non-optimized conditions (0.029) (TEM) NP Ø: 6.61±2.04 nm (slightly lower than the software predicted value nm)

15 CAN DOE - -Fe 2 O 3 NPs Use of the MINITAB 16 software profile optimizer tool (Selected Physico-Chemical Characterization Data) Hydrodynamic NP Ø: 60.00± 1.98 nm XPS & EDAX/ICP analyses confirm elemental Ce presence (higher amounts) 60.0 nm Increased doping Ce amount: Presence of nitrate [CeL n ] 3/4+ complexing ligands on the NP surface N 1s peak: ev BE

16 CAN DOE - -Fe 2 O 3 NPs: chemical modifications using 25kDa b-pei/modified b-pei polymers for gene silencing (sirna delivery) - Selected Physico- Chemical Characterization Data) [CeL n ] 3/4+ cation-stabilized maghemite NPs (CAN-g-Fe 2 O 3 NPs) Fe O(H) Fe [CeL n ] 3/4+ [CeL n [ 3/4+ -based coordination chemistry L L L Ce L L L KDa b-pei (coordination mode) 2. sirna/rna complexation 3/4 + L: Coordinating monodentate/ polydentate ligand (OH, H 2 O, O-N(=O)-O, R- NH 2 and/or R-NH-linker-NH-R' (PEI) ligands) HO O RNA-loaded b-pei 25 -CAN-g-Fe 2 O 3 NPs N O OH Dipicolinic acid (red: coordinating atoms) sirna/rna cell delivery & gene silencing or KDa b-pei (coordination mode) 2. Aq. H 2 O 2, 10 C 3. sirna/rna complexation NP NP RNA-loaded PEI 25-ox -CAN-g-Fe 2 O 3 NPs

17 b-pei 25 -CAN DOE -g-fe 2 O 3 NPs Selected characterization data # w/w b-pei/fe ratio: ±1.55 (TEM) & 82.90±1.26 (DLS) nm # w/w Ce/Fe: # z Potential: mv # Presence of both NO 3 (-) anions/b-pei phase (XPS N 1s peaks at BEs & ev) # TGA analysis: b-pei phase (73.62 w% at C temperature range) # Strong T* 2 contrast NP agent: r 1 & r* 2 relaxivity values of & mmol -1 s -1 # Super-paramagnetic NPs # Effective gene silencing capabilities using a dual luciferase (Firefly & Renilla) system = Human osteosarcoma U2OS-Luc cells

18 b-pei 25 -CAN DOE -g-fe 2 O 3 NPs - Selected characterization data sirna capture at increasing Fe/siRNA w/w ratios sirna capture at increasing b-pei 25 /sirna w/w ratios

19 b-pei 25 -CAN DOE -g-fe 2 O 3 NPs Selected characterization data Gene silencing properties = quite high effectiveness (very low Fe/siRNA w/w ratios)

20 b-pei 25-ox -CAN DOE -g-fe 2 O 3 NPs Selected characterization data & gene silencing capability # 0.1, 0.5 & 5% molar oxidation of b-pei 25 amine groups (sreening experiments) # w/w b-pei/fe ratio: ±2.65 (TEM) & (DLS) nm # w/w Ce/Fe: # z Potential: mv # Super-paramagnetic NPs # Effective gene silencing capabilities using a dual luciferase (Firefly & Renilla) system = Human osteosarcoma U2OS-Luc cells with total absence of in vivo toxicity Luciferase silencing in U2OS-Luc cells by CAN-g-Fe 2 O 3 NPs + PEI + 0.5% mass H [contact process] PEI/Fe=5.25 Luciferase silencing in U2OS-Luc cells by CAN-g-Fe 2 O 3 NPs + PEI + 5% mass H [contact process] PEI/Fe=5.25 % of control control Firefly Renilla % of control control Firefly Renilla Fe/siRNA mass ratio Fe/siRNA mass ratio

21 sirna capture by b-pei 25-ox -CAN DOE -g-fe 2 O 3 NPs at increasing Fe/siRNA w/w ratios 0.1% molar oxidation b-pei 25 # in vivo injection till 4.0 mg sirna/kg (24h: 2 mg/kg + 2 mg/kg) mice alive!

22 # Innovative ultra-small [CeL n ] 3/4+ cation/complex-doped g-fe 2 O 3 NPs = New type of non-toxic magnetic (MRI-enabling) nanoscale inorganic carriers # Effective use of statistically relevant Design of Experiments (DoE) methods for optimization of NP surface engineering (doping step by lanthanide [CeL n ] 3/4+ cations/complexes) # NP Aggregation control executed = new concept using positive metallic cation implantation/doping # Potential straight obtainment of dual / [CeL n ] 3/4+ cation/complex-doped g-fe 2 O 3 NPs On-going work focusing also on hard-totransfect cells 22

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