Purchase this article with an account.
Piotr Stafiej, Sahar Salehi, Jochen Gutmann, Dirk W. Schubert, Friedrich E Kruse, Thomas Bahners, Thomas Armin Fuchsluger; Nanofiber-assembled biomatrix for corneal tissue engineering: Enhanced drug delivery by integration of specific surface linkers. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):4151.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
We have previously demonstrated that Polycaprolactone (PCL) / Poly(glycerol sebacate) (PGS) nanofiber-biomatrix shows properties for ocular surface reconstruction (biodegradability, extracellular matrix (ECM) attributes). Manufactured by electrospinning, this biocompatible scaffold promotes growth of corneal cells. To further optimize the biomatrix for drug delivery we now assembled specific surface groups for immobilization of proteins, like growth-factors or specific cell-binding proteins.
The biomatrix was electrospun in different PCL:PGS blend ratios (1:1, 1:2, 1:3, 1:4) and cut into a sample size of 1 cm2. Fiber surfaces were functionalized by a wet-chemical treatment of the scaffolds. In a first step, amino-functional groups were introduced to existing hydroxyl groups, after which thio-functional groups were added. The amount of thiol groups was analyzed by Ellman’s reagent and subsequently measured. MTT apoptosis tests were performed to determine negative effects following this modification. Fiber morphology was examined by Scanning Electron Microscopy (SEM).
Thiol groups could be introduced by the described wet-chemical process in each PGS containing sample. Interestingly, the amount of introduced thiol groups decreased with increasing concentration of PGS (PGS:PCL 110±3,74 nM [1:1], 51±33 nM [2:1], 23±14 nM [3:1], 8±2 nM [4:1]). Separate samples made of unblended PGS, PCL, and of untreated cotton served as controls. Here, thiol groups could not be established on PCL fibers, while significant amounts were detected on PGS and cotton, both materials having hydroxyl groups. SEM images did not show major changes in fiber morphology. No significant increase of apoptosis could be measured.
Thio-functional groups could be established on the surfaces of a PGS:PCL nanofiber biomatrix by a wet-chemical process. The treatment did not affect fiber morphology and did not significantly increase apoptosis. Hence, the fiber modification did not reactively affect biomatrix properties. Further research will reveal, how binding of specific proteins to these surface groups will increase proliferation and differentiation of corneal cells.
This PDF is available to Subscribers Only