Effect of oxygen plasma on surface properties and biocompatibility of PLGA films

Abstract

In this study, poly(D, L-lactide-co-glycolide) (PLGA) films were prepared by solvent casting method and the surfaces of the films were modified by application of oxygen plasma. A radio frequency (RF) generator working at 13.56 MHz was used to create plasma, and powers at different levels changing between 20 and 300 W were applied. The variations in chemistry, topography and surface free energy (SFE) of the films were investigated by electron spectroscopy for chemical analysis (ESCA), atomic force microscopy (AFM) and goniometer, respectively. The cell-material interactions of the modified samples were evaluated by cell culture tests using 3T3 fibroblast cell line.As the applied power of the RF generator was increased from 20 to 300 W, the surface oxygen content (examined by ESCA) first increased up to 100 W, and then decreased mostly because of crosslink formation by elimination of oxygen. Surface roughness (examined by AFM) and hydrophilicity (examined by water contact angle measurements) increased parallel to the applied power. SFE and the basic component of SFE also increased while the acidic component did not show a significant change with power according to the geometric mean approach. In vitro material-cell interaction studies showed that oxygen plasma modification enhanced the cell attachment and cell proliferation on PLGA samples.

Plasma Surface Modification of Biodegradable Polymers: A Review

“…According to our knowledge, no literature on plasma treatment of polyglycolic acid has been published so far. However, quite a few research articles deal with plasma modification of the copolymer PLGA 122–130. In the past, mostly pure oxygen plasmas have been employed to modify the surface of PLGA 122, 123, 126, 130.…”

“…However, quite a few research articles deal with plasma modification of the copolymer PLGA 122–130. In the past, mostly pure oxygen plasmas have been employed to modify the surface of PLGA 122, 123, 126, 130. For example, Hasirci et al123 applied a low pressure oxygen RF discharge for the surface modification of 50/50 PLGA films and observed an increased hydrophilicity: the PLGA water contact angle decreased from 67° to approximately 38° after plasma treatment.…”

“…In the past, mostly pure oxygen plasmas have been employed to modify the surface of PLGA 122, 123, 126, 130. For example, Hasirci et al123 applied a low pressure oxygen RF discharge for the surface modification of 50/50 PLGA films and observed an increased hydrophilicity: the PLGA water contact angle decreased from 67° to approximately 38° after plasma treatment. Untreated and plasma‐treated PLGA films were studied with FTIR to discover changes in chemical composition but similar to the PLA films, no differences could be detected.…”

Non-Thermal Plasma Surface Modification of Biodegradable Polymers

“…However, quite a few research articles deal with plasma modification of the copolymer PLGA (Khorasani et al, 2008, Hasirci et al, 2010, Khang et al, 2002, Park et al, 2007, Park et al, 2010, Safinia et al, 2007, Safinia et al, 2008, Shen et al, 2008, Wang et al, 2004. 50/50 PLGA films were modified in an oxygen plasma at low pressure and a decrease of the contact angle from 67° to below 40° after plasma treatment was observed.…”

Benefits of oxygen and nitrogen plasma treatment in Vero cell affinity to poly(lactide-co-glycolide acid)

“…The characterization study indicated that the surface composition and the functional groups on the surface of PLLA and PHBV after plasma treatment had a great effect on cell affinity of these films 17 . In a comparative study, Croll et al 17 and Hasirci 19 studied the plasma etching effect on PLGA. The results showed an increase of hydrophilicity of PLGA membranes.…”