polymer nanoparticles for rescuing vision in blind retinas

Guglielmo LanzaniCenter for Nano Science and Technology

Istituto Italiano di TecnologiaDept. of Physics, Politecnico di Milano

Oculus ReparoPolymer Nanoparticles for Rescuing

Vision in Blind Retinas

Center for Nano Science and Technology, Istituto Italiano di Tecnologia, Milan, ItalyMaria Rosa Antognazza, Greta Chiaravalli, Daniele Fazzi, Giovanni Manfredi, Sara Perotto. Alumni: Jonathan Barsotti, Sebastiano Bellani, Caterina Bossio, Eleonora Canesi, Andrea Desii, Michele Garbugli, Ester Giussani, Erica Lanzarini, Lucia Laudato, Francesco Lodola, Matteo Porro, Gabriele Tullii, Elena Zucchetti.

Center for Synaptic Neuroscience and Technology, Istituto Italiano di Tecnologia, Genoa, ItalyFabio Benfenati, Elisabetta Colombo, Mattia Difrancesco, Stefano Di Marco, Ermanno D. Papaleo, Cyril Eleftheriou, Giulia Mantero, Mattia Nova, Anna Rocchi, Dmytro Shmal. Alumni: Mattia Bramini, Marco Dal Maschio, Paul Feyen, Diego Ghezzi,

ISMN-ISOF-IMM-CNR Bologna Italy Giovanna Barbarella, Valentina Benfenati, Francesca Di Maria, Stefano Ferroni, Mattia Zangoli

Ospedale Sacro Cuore – Don Calabria (Verona), ItalyMaurizio Mete, Angela Russo, Grazia Pertile

Department of Health Science, Nuclear Medicine, University of Genoa, 16132 Genoa, ItalyAmbra Buschiazzo, Vanessa Cossu, Gianmario Sambuceti, Flavia Ticconi

Department of Biotechnology and Applied Clinical Science, University of L’Aquila, Italy. Silvia Bisti, Mattia Di Paolo, Rita Maccarone

Animal Facility, National Institute Cancer Research, IRCCS AOU San Martino-IST, 16132 Genoa, ItalyMichele Cilli, Laura Emionite

IBFM-CNR, Milan, ItalyCecilia Marini

Innovhub-SSI, Silk Division, 20133 Milan, ItalyIlaria Donelli, Giuliano Freddi

ISTM-CNR Perugia, ItalyEdoardo Mosconi, Paolo Salvatori, Filippo De Angelis

Istituto Officina dei Materiali CNR-IOM SLACS Cagliari, Cittadella Universitaria, 09042 Monserrato (California), ItalyMaria Ilenia Saba, Alessandro Mattoni

Georgia Institute of Technology, Atlanta, Georgia United StatesJean-Luc 6fYdas,Hong Li

Department of Biology - University of Pisa, ItalyJosé Fernando Maya-Vetencourt

Multi disciplinary collaboration

I b]j Yfg]hUdegli Studi di Milano-Bicocca,Milan, ItalySergio Brovelli, Francesco Bruni, Beatriz Santiago Gonzalez

ISASI-CNR, Naple, ItalyAngela Tino, Claudia Tortiglione

Politecnico di Milano, ItalyChiara Bertarelli, Cosimo D’Andrea, Francesco Scotognella

Università degli Studi di Bari “Aldo Moro”Dr. R. Ragni, Dr. D. Vona, Dr. E. Altamura, Prof. G. M. Farinola

OUTLINE

• Motivation

• Retina Prosthesis

• P3HT and Nanoparticles Photophysics

• Optostimulation mechanism

Il più sofisticato organo di senso

“To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree.”

Charles Darwin

Guglielmo Lanzani

The Retina

Guglielmo Lanzani

Evolution Strategy

George Wald

Nobel Prize in Physiology or Medicine

1967

Octopus

Great salad

The Blind Spot

1 mm

blood vessel-free

Distribuzione spaziale dei fotorecettori

2.3 micron10 micron

Guglielmo Lanzani

A broad field of view

Guglielmo Lanzani

How the brain perceives the world

I fotorecettori rispondono alla luce

Peacock Mantis

Third among the global causes of visual impairment with a blindness prevalence of 8,7%.

The World Health Organization assesses that 50 million persons suffer from AMD symptoms and 14 million persons are blind or severely visually impaired because of AMD.

It is the primary cause of visual deficiency in industrialized countries.

Motivation | Prosthesis | Photophysics | Mechanism

Age-related macular degeneration (AMD)

Retinitis Pigmentosa

Early Symptoms:Decreased night vision, loss of peripheral (side) vision

Late Symptoms:Vision loss, blindness

Inherited disease

1 in 3-4000 people1,5 M people worldwide


Organic Semiconductors Motivation | Prosthesis | Photophysics | Mechanism

IDEAMotivation | Prosthesis | Photophysics | Mechanism

Poly 3 hexhyl Thiophene Rods and Cones

Spectral Response

S n


20

• Motivation




P3HT NANOPARTICLES

P3HT nanoparticles

S n

Chem. Soc. Rev., 2018 10.1039/C7CS00860K

1 µm

10 µm


F. Benfenati

Maurizio Mete Grazia Pertile Grazia Pertile


Nanoparticles in retina

Microinjection

OCT Retina reattachment

No washout over time

P3HT-NPs

Wide retina coverage

P3HT-NPs

Nature Nanotechnology 15 (8), 698-708 (2020)


Pre

Post

30 DPI

240 DPI

Rescue of pupillary reflex in RCS rats subretinally microinjected with in P3HT-NPs


Light-Dark Test (5 lux)

Rescue of visually driven behavior in RCS rats subretinally microinjected with in P3HT-NPs

Nature Nanotechnology 15, 698 (2020)


Time Spent in the DarkEscape Latency

Light-evoked metabolic activation of V1 is rescued in dystrophic RCS rats injected with P3HT nanoparticles

240 DPI


VEPs

RCS

Long-Evans

1.0

0

1

0.1

VEP

ampl

itude

Spatial frequency (c per deg)

How to measure visual acuity ?Motivation | Prosthesis | Photophysics | Mechanism

Visual AcuityNature Nanotech 15 (8), 698-708 (2020)Motivation | Prosthesis | Photophysics | Mechanism

• Motivation




P3HT in contact with electrolyte

A

SC

NeAVCε2

2 2=−

ITO

PEl

Nitrogen

Air

Liquid+light

Cexp=180 nF

d < 15 nm

Cg = 17,8 nF(Mott-Schottky)

Nature Photonics 7, 400 (2013), J. Phys. Chem. C 118, 6291(2014)

Surface Polarization Drives Photoinduced Charge Separation at the P3HT / Water Interface

ACS Energy Lett. , 2016, 1 (2), pp 454–463

P. Salvatori, E. Mosconi, M. Saba, A. Mattoni, H. Li, J-L. Brédas, F. De Angelis


Nanoparticle Absorption

Aggregates ~24%

Exciton bandwidth W=33 meV

I. Bargigia et al. ChemBioChem 2018, 19, 1 – 6


0,4 0,8 1,2 1,6 2,0 2,4 2,8

103

2x103

3x103

4x103

5x1036x1037x103

Inte

nsity

(a.u

)

q (Å-1)

200nm ai=0-1° 200nm ai=0.15°

100

010

-20 0 20 400,0

0,5

1,0

KRK Living Cell Water

Time (ps)

#5 αi=0.15°

#4 αi=0.1°

#7 αi=0.05°d100=1.67nm P3HT lamellar stackingd010=0.38nm P3HT π-π stacking

GIWAXS of P3HT NPs (200nm) spry coated on silicon TRPL

L L ~ 12 nm20

0nm

Fabiola Liscio CNR-IMM Bologna (I)

• Motivation




30 DPI 240 DPIP3HT NPs do not promote photoreceptor survival in dystrophic retinas

50 μm


Experimentum crucis


10 W/cm2

Office (500 Lux) ~ 25 mW/cm2

Sun Light 104-105 luxTV studio 103 luxOffice 500 luxMoonlight 1 lux

ILLUMINANCE [lux=lm/m2]


Photo-excitation mechanisms

CAPACITIVE FARADAIC

THERMAL CHEMICAL

𝑖𝑖𝑚𝑚 = 10 𝜇𝜇𝜇𝜇

𝐽𝐽𝑚𝑚 = 1𝑘𝑘𝜇𝜇𝑐𝑐𝑐𝑐2

𝑄𝑄𝑚𝑚 = 10𝜇𝜇𝜇𝜇𝑐𝑐𝑐𝑐2


A A-

𝐼𝐼 = 1W𝑐𝑐𝑐𝑐2


𝑧𝑧 = 𝑡𝑡𝑡𝑡𝑡𝑡 × y ≈ 𝑡𝑡 × y ≅ 1,22 𝜆𝜆2p y = 7 � 10−4 𝑐𝑐𝑐𝑐

a=π z2

I (corneal) = 20 lux= 20 lm/m2

λ=555 nm2p=0.1 cm (pupil diameter)

Pupil reflex

𝑃𝑃 = 𝐼𝐼 × 𝜋𝜋𝑝𝑝2

𝐼𝐼𝑅𝑅 =𝑃𝑃𝜋𝜋𝑧𝑧2

= 𝐼𝐼𝑝𝑝2

𝑧𝑧2≈ 15

𝑐𝑐W𝑐𝑐𝑐𝑐2 ≪ 1

W𝑐𝑐𝑐𝑐2

y=1 cm


∆𝑇𝑇 =𝐼𝐼0𝜋𝜋𝑅𝑅𝑁𝑁𝑁𝑁2

4𝜋𝜋𝑘𝑘𝑟𝑟𝐼𝐼0: light intensity (1 mW/cm2)𝑅𝑅𝑛𝑛𝑛𝑛: Nanoparticle radius (175 nm)𝑘𝑘: thermal conductivity of water (0.6 W/mK)𝑟𝑟: distance from nanoparticle centre

𝑟𝑟Nanoparticle heating:

At the particle surface: ∆𝑇𝑇~10_7 K

In VIVO thermal effect can be ruled out


Guglielmo Lanzani

Photo-excitation mechanisms

CAPACITIVE FARADAIC

THERMAL CHEMICAL

𝑖𝑖𝑚𝑚 = 10 𝜇𝜇𝜇𝜇

𝐽𝐽𝑚𝑚 = 1𝑘𝑘𝜇𝜇𝑐𝑐𝑐𝑐2



A A-

𝐼𝐼 = 10𝑐𝑐W𝑐𝑐𝑐𝑐2


Future Perspectives

Transferring to human experimentation

Cure degenerative blindness

Future perspectivesin brain stimulation

Transformational potential:Novel approach for neuronal stimulation and for the cure of retina and brain diseases

ORGANIC NANOPARTICLES

Funding

Premio Nazionale Innovazione

Mr. Monti

Ra.Mo

OLIMPIA

Fondazione 13 Marzo

polymer nanoparticles for rescuing vision in blind retinas

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