Filtern
Dokumenttyp
- Zeitschriftenartikel (2)
- Vortrag (1)
Sprache
- Englisch (3)
Schlagworte
- Multiphoton lithography (3) (entfernen)
Organisationseinheit der BAM
Eingeladener Vortrag
- nein (1)
Mussel-inspired polydopamine (PDA) initiated a multifunctional modification route that leads to the generation of novel advanced materials and their applications. However, existing PDA deposition techniques still exhibit poor spatial control, have a very limited capability of micropatterning and do not allow to locally tune PDA topography. Herein, we demonstrate PDA deposition based on Multiphoton Lithography (MPL) that enables full spatial and temporal control with nearly total freedom of patterning design. Using MPL, we achieve 2D microstructures of complex design with pattern precision of 0.8 μm without the need of a photomask or stamp. Moreover, this approach permits adjusting the morphology and thickness of the fabricated microstructure within one deposition step, resulting in a unique tunability of materials properties. The chemical composition of PDA is confirmed and its ability for protein enzyme immobilization is demonstrated. This work presents a new methodology for high precision and complete control of PDA deposition, enabling PDA incorporation in applications where fine and precise local surface functionalization is required. Possible applications include multicomponent functional elements and devices in microfluidics or lab-on-a-chip systems.
Inspired by the chemistry of mussel adhesive proteins, polydopamine (PDA has been shown as one of the most versatile platforms for altering the properties and incorporating new functionalities to nearby any material surface despite its nature. Rich chemistry of PDA enables broad variety of surface modification and diverse secondary reactions that makes it extremely interesting for a wide range of application including biomedical field, e.g., drug delivery, adhesives, cell adhesion, biosensing. Despite high potential of polydopamine, the lack of deposition control and precision in existed methods limits their applications in microdevices and miniaturized functional systems like, for example, MEMS, microfluidic and sensorics.
Herein, we demonstrate a novel maskless approach for surface micropatterning with polydopamine based on Multiphoton Lithography that overcomes present limitations. Neither strong oxidants, metal ions nor adjustment of pH to alkaline is required by this technique. The spatial resolution down to 0.8 µm has been achieved which is at least an order of magnitude smaller than shown by other existed methods. We are able to control the morphology and thickness of the micropattern by altering fabrication parameters allowing structure gradient.
Apart from the glass substrate, we achieved PDA patterning at surfaces of different nature such as polychlorotrifluoroethylene, polydimethylsiloxane, polyethylene terephthalate, silicon wafers, and fluorinated glass coverslips. Post-modification of polydopamine micropatterns with protein enzyme like trypsin is demonstrated to highlight its sensing potential.
Presented in this work microfabrication technique empowers advanced applications of mussel-inspired materials in single-molecule bioassays, sensors and other complex microdevices.
Long-time behavior of surface properties of microstructures fabricated by multiphoton lithography
(2021)
The multiphoton lithography (MPL) technique represents the future of 3D microprinting, enabling the production of complex microscale objects with high precision. Although the MPL fabrication parameters are widely evaluated and discussed, not much attention has been given to the microscopic properties of 3D objects with respect to their surface properties and time-dependent stability. These properties are of crucial importance when it comes to the safe and durable use of these structures in biomedical applications. In this work, we investigate the surface properties of the MPL-produced SZ2080 polymeric microstructures with regard to the physical aging processes during the post-production stage. The influence of aging on the polymeric microstructures was investigated by means of Atomic Force Microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). As a result, a time-dependent change in Young’s Modulus, plastic deformation, and adhesion and their correlation to the development in chemical composition of the surface of MPL-microstructures are evaluated. The results presented here are valuable for the application of MPL-fabricated 3D objects in general, but especially in medical technology as they give detailed information of the physical and chemical time-dependent dynamic behavior of MPL-printed surfaces and thus their suitability and performance in biological systems.