Biopolymer Thin Films Synthesized by Advanced Pulsed Laser Techniques

Abstract

This chapter provides an overview of recent advances in the field of laser-based synthesis of biopolymer thin films for biomedical applications. The introduction addresses the importance of biopolymer thin films with respect to several applications like tissue engineering, cell instructive environments, and drug delivery systems. The next section is devoted to applications of the fabrication of organic and hybrid organic-inorganic coatings. Matrix-assisted pulsed laser evaporation (MAPLE) and Combinatorial-MAPLE are introduced and compared with other conventional methods of thin films assembling on solid substrates. Advantages and limitations of the methods are pointed out by focusing on the delicate transfer of bio-macromolecules, preservation of properties and on the prospect of combinatorial libraries' synthesis in a single-step process. The following section provides a brief description of fundamental processes involved in the molecular transfer of delicate materials by MAPLE. Then, the chapter focuses on the laser synthesis of two polysaccharide thin films, namely Dextran doped with iron oxide nanoparticles and Levan, followed by an overview on the MAPLE synthesis of other biopolymers. The chapter ends with summary and perspectives of this fast-expanding research field, and a rich bibliographic database.

Biomimetic Coatings Obtained by Combinatorial Laser Technologies

“…They are in the forefront of several discoveries in nanoscience and nanotechnology. Laser-based deposition techniques have been widely employed for the fabrication of various thin biomimetic composite coatings [7,63,[95][96][97][98]. The book edited by Schmidt and Belegratis [99] presents a detailed state-of-the-art of the laser technologies until seven years ago as well as the materials that are typically employed in cutting-edge biomimetic applications.…”

“…By readapting setup configurations, in particular employing multiple pulsed laser beams and/or multi-targets, combinatorial-PLD and combinatorial-MAPLE were developed to fabricate thin blended coatings with a gradient of composition in a single-step process. The key benefits and drawbacks of these techniques have been previously addressed in a comparison with other non-laser-based methods [7,62,63,97] and are briefly summarized in the following. Both methods are highly versatile, with individual process parameters able to control and tailor morphological and structural coating properties.…”

“…MAPLE process uses milder conditions (e.g., laser energies one order of magnitude lower than in case of PLD), just above the threshold of frozen target vaporization. It therefore allows for the fabrication of either inorganic, organic, or hybrid coatings with a high versatility [59,96,97,[102][103][104][105]. MAPLE offers specific benefits with respect to PLD, demonstrated by the safe transfer and deposition of delicate compounds such as proteins [106,107] or biopolymers, without impeding on the stability of their functional characteristics, which rely on preserving their nanoscale structure [103].…”

Composite Coatings Based on Renewable Resources Synthesized by Advanced Laser Techniques

“…In spite of the vast list reported in the literature of biomaterials deposited in form of thin films, each of the above-mentioned methods have some limitations in terms of coating thickness, multilayer deposition, adherence, composition or crystallinity. Between all techniques, laser-based technologies are exhibiting a lot of advantages, as: fabrication of a wide range of different biomaterials, controlled film thickness, good adhesion to substrate [55]. Furthermore, laser-based technologies imply a low material consumption and ensure the stoichiometry preservation of the growing films [39].…”

“…This brand new developed technique-Combinatorial-MAPLE-stands for a simple, single step, biofabrication path which can easily limit the time of manipulation and biomaterials consumption [55].…”