Atmospheric pressure cold plasma versus wet-chemical surface treatments for carboxyl functionalization of polylactic acid: A first step toward covalent immobilization of bioactive molecules

On the Effectiveness of Oxygen Plasma and Alkali Surface Treatments to Modify the Properties of Polylactic Acid Scaffolds

“…A n insignificant increase of the O/C ratio was obtained when comparing PLA and PLASMA 1 min groups of samples. Similar results were obtained in previous studies that carried out a comparison between oxygen plasma and alkali treatments [ 32 ]. Reactive species contained in the oxygen plasma (which include neutral oxygen molecules and atoms, radicals, free electrons, and positively and negatively charged ions [ 22 , 40 ]) are less prone to react with the carbonyl groups of the polymer chain than hydroxide ions, giving the strong nucleophilic nature of the latter [ 41 ].…”

“…Results of the TBO test (as illustrated in Figure 1 ) showed that the 0.2 N NaOH + citric acid group had the highest concentration of carboxyl groups on their surface. This was an expected result, since carboxyl groups are predominantly incorporated when applying an alkali treatment method [ 32 ] and the subsequent washing step with an organic acid adds more of these hydrophilic groups onto the PLA surface by ester bond´s hydrolysis [ 14 , 18 ]. Carboxyl groups were also generated, albeit to a lesser extent, by applying the alkali treatments coupled with a washing step using an inorganic acid (HCl) or in the scaffolds treated with the PLASMA 10 min method.…”

“…In addition, the use of organic and inorganic acids as a final washing step after alkali treatment was evaluated. Few examples can be cited from the literature comprising an experimental assessment of different treatment methods with varying conditions applied to PLA surfaces, including films [ 32 ] and composite samples [ 33 ], but no references were found regarding 3D structures. In addition, there is a lack of information in the literature about the comparison of how the surface modifications on PLA surfaces evolve over time.…”

Supercritical Impregnation of PLA Filaments with Mango Leaf Extract to Manufacture Functionalized Biomedical Devices by 3D Printing

“…Nevertheless, the use of polymers as manufacturing material for biomedical devices also presented some drawbacks with regard to biocompatibility. Thus, underperformance or the proliferation of certain cells [ 9 ] could represent a hazard for the patient. On the other hand, in the specific case of PLA, due to its hydrophobicity, it is specially difficult for cells to become attached onto its surface [ 10 ].…”

Facile control of the surface property and hydrolytic degradation of poly(l-lactide) materials by coating poly(l-lactide)-based triblock copolymers with hydrophilic or hydrophobic block

“…10,11 However, in addition to surface properties and hydrolytic degradation behavior and rate, bulk physical properties such as mechanical and thermal properties are altered by these methods. Surface treatments such as polymer coating [15][16][17] and alkali-treatment [18][19][20][21][22][23][24] are promising and versatile methods to control surface properties and hydrolytic degradation behavior and rate without altering the bulk physical properties. Another advantage of surface treatments is their applicability on site after processing or molding of polymer materials and thereby the surface property is controllable on site.…”