Deposition of Chitosan on Plasma-Treated Polymers—A Review

Abstract

Materials for biomedical applications often need to be coated to enhance their performance, such as their biocompatibility, antibacterial, antioxidant, and anti-inflammatory properties, or to assist the regeneration process and influence cell adhesion. Among naturally available substances, chitosan meets the above criteria. Most synthetic polymer materials do not enable the immobilization of the chitosan film. Therefore, their surface should be altered to ensure the interaction between the surface functional groups and the amino or hydroxyl groups in the chitosan chain. Plasma treatment can provide an effective solution to this problem. This work aims to review plasma methods for surface modification of polymers for improved chitosan immobilization. The obtained surface finish is explained in view of the different mechanisms involved in treating polymers with reactive plasma species. The reviewed literature showed that researchers usually use two different approaches: direct immobilization of chitosan on the plasma-treated surface or indirect immobilization by additional chemistry and coupling agents, which are also reviewed. Although plasma treatment leads to remarkably improved surface wettability, this was not the case for chitosan-coated samples, where a wide range of wettability was reported ranging from almost superhydrophilic to hydrophobic, which may have a negative effect on the formation of chitosan-based hydrogels.

The Ageing of μPlasma-Modified Polymers: The Role of Hydrophilicity

“…Moreover, all the new peaks that appeared on the HDPE surface after the μPlasma modification were attributed to oxygen-containing polar groups, indicating that the functional groups on the HDPE surface reacted with the oxygen in the plasma during the treatment process. These newly formed polar functional groups are known to give higher hydrophilicity to the polymer surface [ 28 , 29 ]. However, over a period of five hours post-treatment, there was a decrease in the intensity of all treatment-associated bands.…”

From Basics to Frontiers: A Comprehensive Review of Plasma-Modified and Plasma-Synthesized Polymer Films

“…It overlaps with the extreme end of the UVC range and extends into even shorter wavelengths. Plasma UV radiation can result in the breakdown and crosslinking of carbon chains in the uppermost layers of the polymer, leading to enhancements in the polymer's durability and mechanical properties [137,138,139] . Experiments involving nanoscratching, as conducted by Tajima et al, demonstrate an appreciable increase in surface shear resistance of plasma-modified LDPE.…”

Intelligent Materials and Nanomaterials Improving Physical Properties and Control Oriented on Electronic Implementations

“…The advanced manufacturing approaches include different versatile techniques (see Table 1), such as 3D printing [6][7][8][9][10][11][12][13][14][15], 4D printing [16][17][18][19][20] (3D printing adding the time variable), innovative materials to be processed in actual industrial manufacturing processes [21][22][23][24][25][26][27][28], laser manufacturing [29][30][31][32][33][34][35][36][37], pulsed spray techniques [38][39][40][41][42][43], electrospinning techniques [44][45][46], and plasma treatments [47][48][49][50]. In Figure 3 are illustrated some graphical elements of the above-mentioned topics.…”

“…Finally, plasma treatment [47][48][49][50] is used to change the material's surface morphology and properties. For this application, AI could indicate the local regions to treat, gaining wettability or bio-functionalization properties or maintaining the metallic surface characteristics over time (including cleaning actions, refreshing the surface properties).…”