The dysregulation of microRNAs (miRNAs) has been implicated in a variety of pathologies, such as inflammatory and autoimmune diseases, neurological disorders, as well as several types of cancer. Anti-miRNA platforms highly effective in in-vitro cell assays have been reported, but translation to the clinic is hampered by poor in-vivo stability of nucleic acids and ineffective uptake of nucleic acids by target cells. This study aims to overcome these obstacles by designing, producing and testing new miRNA targeting materials constituted by Peptide Nucleic Acids (PNAs, synthetic mimics of natural DNA and RNA) [1]. Indeed, PNAs conjugate the effectiveness of the natural nucleic acids targeting with chemical/thermal stability and resistance to enzymatic biodegradation. A novel efficient method has been developed for covalently linking Peptide Nucleic Acid (PNA) oligomers and superparamagnetic iron oxide nanoparticles (SPION), to produce water soluble hybrid nanomaterials that can act as MRI contrast agents, as hyperthermia promoters and as PNA carriers. The multistep procedure involveed: (i) preparation of oleate-stabilized SPION by using the thermal decomposition method, to control the size of the magnetic core; (ii) exchange of the oleate layer by dimercaptosuccinic acid (DMSA), to impart water solubility and to provide functional groups for PNA grafting; (iii) functionalization of a PNA oligomer with a terminal maleimide moiety, to allow SPION–PNA conjugation by thiol-maleimide Michael addition reaction, exploiting the SH groups of DMSA on the SPION surface. The method was tested using a model PNA decamer containing all four nucleobases (–CTAGATCACT–). SPION–PNA conjugation by SH addition was found more efficient than conjugation through amide bond between the COOH groups of DMSA and the terminal NH2 groups of PNA. Elemental analysis, UV-Vis and IR spectra, ζ-potential, TEM, AFM, relaxivity and magnetic measurements of the SPION used for PNA binding is reported, and compared to the one relative to the SPION–PNA conjugate.

Superparamagnetic iron oxide nanoparticles functionalized by peptide nucleic acids / M. Galli, A. Guerrini, S. Cauteruccio, P. Thakare, D. Dova, F. Orsini, P. Arosio, C. Carrara, C. Sangregorio, A. Lascialfari, D. Maggioni, E. Licandro. ((Intervento presentato al 9. convegno International Symposium on Nano & Supramolecular Chemistry tenutosi a Napoli nel 2017.

Superparamagnetic iron oxide nanoparticles functionalized by peptide nucleic acids

M. Galli;S. Cauteruccio;P. Thakare;F. Orsini;P. Arosio;A. Lascialfari;D. Maggioni;E. Licandro
2017

Abstract

The dysregulation of microRNAs (miRNAs) has been implicated in a variety of pathologies, such as inflammatory and autoimmune diseases, neurological disorders, as well as several types of cancer. Anti-miRNA platforms highly effective in in-vitro cell assays have been reported, but translation to the clinic is hampered by poor in-vivo stability of nucleic acids and ineffective uptake of nucleic acids by target cells. This study aims to overcome these obstacles by designing, producing and testing new miRNA targeting materials constituted by Peptide Nucleic Acids (PNAs, synthetic mimics of natural DNA and RNA) [1]. Indeed, PNAs conjugate the effectiveness of the natural nucleic acids targeting with chemical/thermal stability and resistance to enzymatic biodegradation. A novel efficient method has been developed for covalently linking Peptide Nucleic Acid (PNA) oligomers and superparamagnetic iron oxide nanoparticles (SPION), to produce water soluble hybrid nanomaterials that can act as MRI contrast agents, as hyperthermia promoters and as PNA carriers. The multistep procedure involveed: (i) preparation of oleate-stabilized SPION by using the thermal decomposition method, to control the size of the magnetic core; (ii) exchange of the oleate layer by dimercaptosuccinic acid (DMSA), to impart water solubility and to provide functional groups for PNA grafting; (iii) functionalization of a PNA oligomer with a terminal maleimide moiety, to allow SPION–PNA conjugation by thiol-maleimide Michael addition reaction, exploiting the SH groups of DMSA on the SPION surface. The method was tested using a model PNA decamer containing all four nucleobases (–CTAGATCACT–). SPION–PNA conjugation by SH addition was found more efficient than conjugation through amide bond between the COOH groups of DMSA and the terminal NH2 groups of PNA. Elemental analysis, UV-Vis and IR spectra, ζ-potential, TEM, AFM, relaxivity and magnetic measurements of the SPION used for PNA binding is reported, and compared to the one relative to the SPION–PNA conjugate.
set-2017
Settore CHIM/03 - Chimica Generale e Inorganica
Settore CHIM/06 - Chimica Organica
Superparamagnetic iron oxide nanoparticles functionalized by peptide nucleic acids / M. Galli, A. Guerrini, S. Cauteruccio, P. Thakare, D. Dova, F. Orsini, P. Arosio, C. Carrara, C. Sangregorio, A. Lascialfari, D. Maggioni, E. Licandro. ((Intervento presentato al 9. convegno International Symposium on Nano & Supramolecular Chemistry tenutosi a Napoli nel 2017.
Conference Object
File in questo prodotto:
File Dimensione Formato  
abstract_poster_napoli_2017.pdf

accesso aperto

Tipologia: Altro
Dimensione 371.28 kB
Formato Adobe PDF
371.28 kB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/556080
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact