NMR guided design of an electrospunnanofiber with antibacterial properties

Simona Tomaselli, Katiuscia Pagano, Henriette Molinari, Laura Ragona

NMR LaboratoryIstituto per lo Studio delle Macromolecole, ISMAC-CNR

Via A. Corti 12, Milanoe-mail: laura.ragona@ismac.cnr.it

Solution NMR of biomacromolecules: supramolecular interactions

KINETICS

NMR

AGGREGATION

A-FABP

PPARg LBD

INTERACTIONSprotein-protein &

protein-ligand interactions

DYNAMICS

DRUG DESIGN

FGF2

FGFR

NANO-CARRIERS

Aggregation kinetics of amyloid peptide

Pagano et al., Plos One, 2012

Ronca et al., Cancer Cell, 2015

Tomaselli et al., Chem. Neurosci., 2017

Tomaselli et al., FEBS J., 2015Ragona et al., BBA, 2014

Bile acid binding protein as an host system

-as a carrier of lipophilic molecules

BABP as host system to be exploited

-for encapsulation of bioactive molecules, fluorescente dyes, antibacterial molecules

(covalent and non-covalent complexes)

2 nm

2 nm

0.8 nm

host

Development of host-guest systems for applications in optoelectronics

F17

Y14

M73

V38

M107 H98

F113R120

E109

L118

A B

BABP rhodamine

NMR interaction studies

400 450 500 550 600

Op

tical A

bso

rpti

on

Wavelength (nm)

a

b

c

d

RHD 10-4M

RHD 10-5M

BABP:RHD

BABP:GCDA:RHD

Rhodamine is encapsulated in BABP

The bio host-guest complex is preserved in the solid state

Rhodamine, encapsulated in BABP, behaves as a monomer in solution

Tomaselli S, Giovanella U, Pagano K, Leone G, Zanzoni S, Assfalg M,

Meinardi F, Molinari H, Botta C, Ragona L.

Biomacromolecules, 2013

Fiber functionalization

Non-woven nano textiles obtained using the electrospinning technique areattractive materials for a wide range of high-tech applications.

Their ultrathin diameter, the good control of their internal structure, density, and porosity make them ideal for very specific applications such as

filtration, sanitary textiles and wound dressing.

Controllable composition and hosting allow to create breathable fiber mats withuploaded functional molecules

such as antibiotics, vitamins, growth factors, metals, antibacterial molecules.

NMR guided design of an electrospun nanofiber with antibacterial properties

Bile acid binding protein

a broad-spectrum antibacterial molecule

promiscuous carrier of lipophilic molecules

NMR

BABP binds Irgasan within its barrel cavity

F

G

H

I

J

8091

111123

85

98

102

B ACDE

Helix I

Helix II

71

65

62

61

72

75

77

F 180°

Combination of:poly(ethylene oxide) PEO

(easily processable, ensures good mechanical properties of

the final product) and Keratin

(increases skin compatibility,favours the healing process)

Keratin:PEO70:30

BABP: IRG

Nanofiber mean diameter 100-120 nm

BABP:IRG complex is uploaded in a keratin/PEO matrix

Perspectives Drug release properties

Cross-linking to modify and tune the fiber biodegradation rate

Tune nanofiber properties according to the selected guests

Lipid binding protein

Keratin/PEO

Irgasan

The lipid carrier protein retains the antibacterial agent in the obtained nanofiber.

The nanofiber maintains its functional properties for at least three months

Antibacterial activity of nanofibers

Tomaselli S, Ramirez DO, Carletto RA, Varesano A, Vineis C, Zanzoni S, Molinari H, Ragona L.. MacromolBiosci, 2016

Silk fibroin

2016-2018 CNR-ANAS (Azerbaijan) bilateral projectHenriette Molinari, Laura Ragona, Chiara Botta

Title: “BIOMAT: EPR, FT-IR, Confocal Raman and NMR spectroscopies aimed atelucidation of structural and photophysical properties of biomaterials”

• Aggregation state of silk fibroin

• Fibroin/rhodamine interaction studies bysolution NMR

• Photophysical characterization of RHD filmsobtained incorporating RHD in fibroin through:

i) silkworms supply (bio-incorporation) andii) in vitro formation of non covalent host-guest

complex

Diffusion Ordered NMR Spectroscopy