TY  - JOUR
A1  - Lützow, Karola
A1  - Hommes-Schattmann, Paul J.
A1  - Neffe, Axel T.
A1  - Ahmad, Bilal
A1  - Williams, Gareth R.
A1  - Lendlein, Andreas
T1  - Perfluorophenyl azide functionalization of electrospun poly(para-dioxanone)
JF  - Polymers for advanced technologies
N2  - Strategies to surface-functionalize scaffolds by covalent binding of biologically active compounds are of fundamental interest to control the interactions between scaffolds and biomolecules or cells. Poly(para-dioxanone) (PPDO) is a clinically established polymer that has shown potential as temporary implant, eg, for the reconstruction of the inferior vena cava, as a nonwoven fiber mesh. However, PPDO lacks suitable chemical groups for covalent functionalization. Furthermore, PPDO is highly sensitive to hydrolysis, reflected by short in vivo half-life times and degradation during storage. Establishing a method for covalent functionalization without degradation of this hydrolyzable polymer is therefore important to enable the surface tailoring for tissue engineering applications. It was hypothesized that treatment of PPDO with an N-hydroxysuccinimide ester group bearing perfluorophenyl azide (PFPA) under UV irradiation would allow efficient surface functionalization of the scaffold. X-ray photoelectron spectroscopy and attenuated total reflectance Fourier-transformed infrared spectroscopy investigation revealed the successful binding, while a gel permeation chromatography study showed that degradation did not occur under these conditions. Coupling of a rhodamine dye to the N-hydroxysuccinimide esters on the surface of a PFPA-functionalized scaffold via its amine linker showed a homogenous staining of the PPDO in laser confocal microscopy. The PFPA method is therefore applicable even to the surface functionalization of hydrolytically labile polymers, and it was demonstrated that PFPA chemistry may serve as a versatile tool for the (bio-)functionalization of PPDO scaffolds.
KW  - biological applications of polymers
KW  - fibers
KW  - functionalization of polymers
KW  - microstructure
Y1  - 2018
U6  - https://doi.org/10.1002/pat.4331
SN  - 1042-7147
SN  - 1099-1581
VL  - 30
IS  - 5
SP  - 1165
EP  - 1172
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Hommes-Schattmann, Paul J.
A1  - Neffe, Axel T.
A1  - Ahmad, Bilal
A1  - Williams, Gareth R.
A1  - Vanneaux, Valerie
A1  - Menasche, Philippe
A1  - Kalfa, David
A1  - Lendlein, Andreas
T1  - RGD constructs with physical anchor groups as polymer co-electrospinnable cell adhesives
JF  - Polymers for advanced technologies
N2  - The tissue integration of synthetic polymers can be promoted by displaying RGD peptides at the biointerface with the objective of enhancing colonization of the material by endogenous cells. A firm but flexible attachment of the peptide to the polymer matrix, still allowing interaction with receptors, is therefore of interest. Here, the covalent coupling of flexible physical anchor groups, allowing for temporary immobilization on polymeric surfaces via hydrophobic or dipole-dipole interactions, to a RGD peptide was investigated. For this purpose, a stearate or an oligo(ethylene glycol) (OEG) was attached to GRGDS in 51-69% yield. The obtained RGD linker constructs were characterized by NMR, IR and MALDI-ToF mass spectrometry, revealing that the commercially available OEG and stearate linkers are in fact mixtures of similar compounds. The RGD linker constructs were co-electrospun with poly(p-dioxanone) (PPDO). After electrospinning, nitrogen could be detected on the surface of the PPDO fibers by X-ray photoelectron spectroscopy. The nitrogen content exceeded the calculated value for the homogeneous material mixture suggesting a pronounced presentation of the peptide on the fiber surface. Increasing amounts of RGD linker constructs in the electrospinning solution did not lead to a detection of an increased amount of peptide on the scaffold surface, suggesting inhomogeneous distribution of the peptide on the PPDO fiber surface. Human adipose-derived stem cells cultured on the patches showed similar viability as when cultured on PPDO containing pristine RGD. The fully characterized RGD linker constructs could serve as valuable tools for the further development of tissue-integrating polymeric scaffolds. Copyright (c) 2016 John Wiley & Sons, Ltd.
KW  - electrospinning
KW  - RGD peptides
KW  - cell adhesion
KW  - biofunctionalization
Y1  - 2017
U6  - https://doi.org/10.1002/pat.3963
SN  - 1042-7147
SN  - 1099-1581
VL  - 28
SP  - 1312
EP  - 1317
PB  - Wiley
CY  - Hoboken
ER  -