Enhanced calcium ion mobilization in osteoblasts on amino group containing plasma polymer nanolayer

Abstract

BackgroundBiomaterial modifications—chemical and topographical—are of particular importance for the integration of materials in biosystems. Cells are known to sense these biomaterial characteristics, but it has remained unclear which physiological processes bio modifications trigger. Hence, the question arises of whether the dynamic of intracellular calcium ions is important for the characterization of the cell–material interaction. In our prior research we could demonstrate that a defined geometrical surface topography affects the cell physiology; this was finally detectable in a reduced intracellular calcium mobilization after the addition of adenosine triphosphate (ATP).ResultsThis new contribution examines the cell physiology of human osteoblasts concerning the relative cell viability and the calcium ion dynamic on different chemical modifications of silicon–titanium (Ti) substrates. Chemical modifications comprising the coating of Ti surfaces with a plasma polymerized allylamine (PPAAm)-layer or with a thin layer of collagen type-I were compared with a bare Ti substrate as well as tissue culture plastic. For this purpose, the human osteoblasts (MG-63 and primary osteoblasts) were seeded onto the surfaces for 24 h. The relative cell viability was determined by colorimetric measurements of the cell metabolism and relativized to the density of cells quantified using crystal violet staining. The calcium ion dynamic of osteoblasts was evaluated by the calcium imaging analysis of fluo-3 stained vital cells using a confocal laser scanning microscope. The positively charged nano PPAAm-layer resulted in enhanced intracellular calcium ion mobilization after ATP-stimulus and cell viability. This study underlines the importance of the calcium signaling for the manifestation of the cell physiology.ConclusionsOur current work provides new insights into the intracellular calcium dynamic caused by diverse chemical surface compositions. The calcium ion dynamic appears to be a sensitive parameter for the cell physiology and, thus, may represent a useful approach for evaluating a new biomaterial. In this regard, reliable in vitro-tests of cell behavior at the interface to a material are crucial steps in securing the success of a new biomaterial in medicine.

Enhancement of Intracellular Calcium Ion Mobilization by Moderately but Not Highly Positive Material Surface Charges

“…with 100 nm Ti particles obtained from the Center for Microtechnologies (ZFM, University of Technology Chemnitz, Germany) at 1 × 1 × 0.075 cm in size (length × width × depth) for cell analysis, or 2 × 1 × 0.075 cm for ζ-potential analysis as previously reported (Staehlke et al, 2018).…”

Surface phosphonation treatment shows dose-dependent enhancement of the bioactivity of polyetheretherketone

“…21,22 As such, the tailoring of surface chemicals such as in the case of covalent graing of functional groups or biomolecules without the hindrance of the detachment is a promising alternative to coating techniques. Our groups and others have reported that implants with incorporated functional groups such as carboxyl, 23,24 sulfonic groups, 25 amino 26 and phosphonate groups, 27,28 or biomolecules such as RGD peptides 29 and antimicrobial peptides 30 exhibit up-regulated bone cells osteogenic activity in vitro and osseointegration in vivo.…”

In Vitro Comparative Study of Oxygen Plasma Treated Poly(Lactic–Co–Glycolic) (PLGA) Membranes and Supported Nanostructured Oxides for Guided Bone Regeneration Processes

“…Test 1 : For the determination of cell adhesion and osteoblast viability, osteoblasts were cultured on the PLGA experimental (HA, SiO 2 , TiO 2 ) and PLGA control membranes, in triplicate, plating 120,000 cells. At 24 h, the cultures were analysed by the microphotography of osteoblasts [ 16 , 17 , 18 ]. Previously, the cells had been fixed with 70% ethanol for 5 min, as it was not possible to observe them without prior fixation.…”