Applications of polymeric coatings have emerged as a promising direction for preparing multilayered assemblies and controlling surface properties. In addition to providing a foundation for interfacing soft materials onto solid supports, polymers afford opportunities to develop hybrid constructs with properties difficult to achieve using monolayer-based chemical modification methods. In particular, the microenvironments of polymers are proposed to facilitate charge transfer to redox-active sites, manage delivery of chemical substrates, improve product specificity during catalytic transformations, and lend chemical protection to underpinning solid-state supports as well as embedded components. In this article, we highlight selected examples of polymeric materials utilized in electrocatalytic and photoelectrosynthetic fuel production.
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3D printing of drug-eluting bioactive multifunctional coatings for orthopedic applications
Three-dimensional (3D) printing is implemented for surface modification of titanium alloy substrates with multilayered biofunctional polymeric coatings. Poly(lactic-co- glycolic) acid (PLGA) and polycaprolactone (PCL) polymers were embedded with amorphous calcium phosphate (ACP) and vancomycin (VA) therapeutic agents to promote osseointegration and antibacterial activity, respectively. PCL coatings revealed a uniform deposition pattern of the ACP-laden formulation and enhanced cell adhesion on the titanium alloy substrates as compared to the PLGA coatings. Scanning electron microscopy and Fourier-transform infrared spectroscopy confirmed a nanocomposite structure of ACP particles showing strong binding with the polymers. Cell viability data showed comparable MC3T3 osteoblast proliferation on polymeric coatings as equivalent to positive controls. In vitro live/dead assessment indicated higher cell attachments for 10 layers (burst release of ACP) as compared to 20 layers (steady release) for PCL coatings. The PCL coatings loaded with the antibacterial drug VA displayed a tunable release kinetics profile based on the multilayered design and drug content of the coatings. Moreover, the concentration of active VA released from the coatings was above the minimum inhibitory concentration and minimum bactericidal concentration, demonstrating its effectiveness against Staphylococcus aureus bacterial strain. This research provides a basis for developing antibacterial biocompatible coatings to promote osseointegration of orthopedic implants.
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- Award ID(s):
- 2100850
- PAR ID:
- 10426925
- Date Published:
- Journal Name:
- International journal of bioprinting
- Volume:
- 9
- Issue:
- 2
- ISSN:
- 2424-7723
- Page Range / eLocation ID:
- 158-175
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.18063/ijb.v9i2.661
