BioSInt UnitSuperfici ed Interfacce biofunzionali

Cecilia Pederzolli

Istituto "Marie Curie" Pergine

Eleonora BusanaChiara Condler

Stage estivi studenti 2009-2010

LaboratorioScienze Biomoleculari ed Interfacce

Centro Materiali e Microsistemi

CNR Centro Nazionale Ricerche IBF Istituto di BiofisicaM. Dalla Serra

Studio dei fenomeni che avvengono all’interfaccia - biosuperfici, biomembrane -

con duplice obiettivo:

Aumentare la comprensione dei meccanismi molecolari alla base delle malattie

Sviluppare sistemi innovativi di diagnosi e terapia (biomedicina)

Settore di integrazione di diverse discipline: fisica, biologia, chimica

Protein-protein interaction

Cell-protein layer interaction

BIOMATERIALProtein layer

Biointerfaces

The problemMaterials for medical devices have been selected on the basis of mechanical and physical properties, with less consideration given to their interactions with the biological environment

Poor interfacial biocompatibilityPoor interfacial biocompatibility

Surface properties play a crucial roleprotein adsorption, cell adhesion etc. are all surface-induce phenomena and depend on a large extent on the properties of the outer few atomic layers of materials

Cell

to exercise a control over the way in which the biological fluids or individual biomolecules respond to the material surface

surface passivation

ligand

blocking agent

+ + + + + + + +

ligand spacer arm

DNA surface immobilisation

oligonucleotide

1) Reduction of the aspecific adhesion

1) Reduction of the aspecific adhesion

2) Specific immobilisation of biomolecules

2) Specific immobilisation of biomolecules

Goal:Methods for covalent immobilization of biomolecules resulting in better biomolecule activity,

reduced nonspecific adsorption, and greater stability.

Surface modification processes

Drug delivery systems

Using micro nano-capsules (liposomes, particles) the transport and release of drugs and active molecules can be possible in a controlled way

Inhibition of bacterial grown3x3 m

System - in solution - on implants surface

Active principles - PFT bacterial toxins inhibitors - traditional antibacterial molecules - peptides

Active multilayers deposited from liposomes

cell membrane

Lipid-based nano-structured materials

CNR-IBF Trento, MIT Boston

Partnership

no treatm

ent

RFMP treatment

biological sample

lysis buffer

Mix, Incubation & purification

Eluted DNA

time scale (minutes)0 <120 diagnoseblood

Mixer

PCR mix

PCR & detection

Sviluppo di materiali per la realizzazione di microsistemi per l’analisi del DNA in diagnostica

molecolare

surface

inherited diseasesInfections by pathogens...

Molecular diagnostics

Surface analysis and chemical modification of silicon-based materials for the development of a lab-on-chip capable to perform a genetic analysis starting from the extraction of genomic DNA directly from blood to the genetic identification of specific mutations and/or SNPs (single nucleotide polymorphism).

The system is a silicon/pyrex microchip (1x1cm, 6 µL total volume), where whole blood is injected (0.5 µL), DNA is extracted and used as a template for on-chip PCR. Products are revealed by fluorescence detection directly on chip.

Olivetti Jet, Biodiversity, Telethon, Politecnico di Torino

Partnership

DNA IN

DNA OUT

1st channel

10th channel

Channels 2-9

PicoGreen stained genomic DNA

Research overview

Carbon nanotube-based sensors for DNA detection

CNT – fluorescein π stacking interaction

ECL detection by means of Ru(bpy)3

2+ labelled DNA

As expected, the maximum ECL intensity falls in correspondence of Ru(bpy)3

2+ electrochemical oxidation (+1.2 V vs. Ag)

Molecular diagnostics

SEM and TEM analysis

1. Realization of electric contact on CNT cylinder

2. CNT embedding in PDMS matrix3. Thermal treatment at 100 °C4. Electrode detaching from silicon

support5. Electric conductivity test Electrodes

Politecnico di Torino, University of Bologna

Partnership

The first of three voltammetric cycles is indicated by solid line, while the subsequent two by dashed lines. The curve modifications from first to third cycle are indicated by the arrow directions

Valeria AntoniniRamona DallapiccolaLorenzo LunelliMarta MarchiorettoLorenza MarocchiLaura PasquardiniFederica PirasCristina PotrichMayra Tejuca Laura Tosatto Michele VinanteManuela Zanetti

Il gruppo di ricerca