Interaction of Ferromagnetic Shape Memory Alloys and RGD Peptides for Mechanical Coupling to Cells: from Ab Initio Calculations to Cell Studies

Abstract

Due to their magneto‐mechanical coupling and biocompatibility, Fe‐Pd based ferromagnetic shape memory alloys are a highly promising materials class for application as contact‐less magneto‐mechanical transducers in biomedical environments. For use in cell and tissue actuators or strain sensors, sufficient adhesion to mediate strains clearly constitutes a prerequisite. As the RGD sequence is the most important binding motif for mammalian cells, which they express to facilitate adhesion, the potential of RGD coatings to achieve this goal is explored. Employing large‐scale density functional theory calculations the physics of bonding between RGD and Fe‐Pd surfaces, which is characterized by coordinate bonds of O and N atoms to Fe, accompanied by electrostatic contributions, is clarified. Theoretical predictions on adhesion, that are confirmed experimentally, suggest RGD as suitable strain mediator to Fe‐Pd surfaces. On the cell side, favorable adhesion properties of RGD‐coated Fe‐Pd are manifested in cell morphology and spreading behavior. Demonstrating that the adhesion forces between RGD and Fe‐Pd exceed those exerted by cells to the RGD coating, as well as traction forces acting onto integrin bonds, the findings pave the way for novel type of applications as cell and tissue actuator or sensor within the areas of tissue engineering and regenerative medicine.

Adhesion of Neurons and Glial Cells with Nanocolumnar TiN Films for Brain-Machine Interfaces

“…In fact, on ITO, the cell area mean Additionally, with regards to the analysis of the single-cell short-term adhesion behavior, we also investigated the spreading of cells in networks over longer time scales of several days cultured on the electrode materials. Cell spreading, and thereby increase of cell size, is usually coupled to an increased number of adhesion points, which in turn leads to enhanced cell adhesion and improved bioactivity of the underlying substrate material [38,39]. Here, we measured the size of actin phalloidin labeled U-87 MG and SH-SY5Y cells, viz.…”

Ion-irradiation-assisted tuning of phase transformations and physical properties in single crystalline Fe7Pd3ferromagnetic shape memory alloy thin films

“…In contrast, there seems to be no direct correlation between coercivity and ion fluence. The in-plane coercivity for the irradiated and unirradiated samples varies between (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) Oe and can be neglected, while the unirradiated sample reveals (107-110) Oe. Irradiation with 10 14 ions cm −2 nearly doubles coercivity to (224-232) Oe, while with fluence increasing to 5 × 10 15 ions cm −2 , it decreases to a minimum of (32-33) Oe.…”

“…Later, ordered and tetragonal L1 0 FePd attracted interest for data storage applications due to its high uniaxial magnetocrystalline anisotropy [5]. Despite yielding lower maximum theoretical strains than Ni-Mn-Ga [6], Fe 7 Pd 3 is characterized by attractive complementary materials properties, including an 'inverse' MSM effect when compared with Ni-Mn-Ga (Ni-Mn-Ga and Fe-Pd contract parallel and perpendicular to the direction of the magnetic field, respectively), much higher ductility and biocompatibility [7,8], which paves the way for use in medical applications (e.g., as adjustable implants or active elements [9]). Fe 7 Pd 3 exhibits four metastable phases at room temperature, viz.…”

Designing Optimal Scaffold Topographies to Promote Nucleus-Guided Mechanosensitive Cell Migration Using in Silico Models

“…For example, in discerning the origin of observed biological behavior, in silico models enable to sort active regulatory mechanism from passive physics [Nickaeen19,Winkler19]. In silico models also provide complementary data, hardly accessible with in vitro and even less in vivo models: (i) at different scales, very small ones, for example, using methods solving the mechanics of clouds of electrons [Zink13] (ii) and of different type, quantities that cannot be measured directly, called internal state variables in thermodynamics, among which forces and stresses can be found for example [Milan16].…”