Electrochemically Driven Hydroxyapatite Nanoparticles Coating of Medical Implants

Abstract

Calcium phosphates are of great interest for biomedical applications such as bone tissue engineering, bone fillers, drug and gene delivery, and orthopedic and dental implant coating. Here, the first electrochemically driven coating of medical implants using hydroxyapatite (HAp) nanoparticles (NPs) as building blocks is reported. This uncommon combination offers a simple, straightforward, and economic process with well controllable, pure, single‐phase HAp. Crystalline, pure HAp NPs are formed by precipitation reaction. The HAp NPs are dispersed by either citrate or poly(acrylic acid) to form pH sensitive dispersion. Controllable and homogeneous coating of medical implants is accomplished by altering the pH on the surface upon applying either a constant potential or current. The process involves protonation of the carboxylic acid moieties, which causes the irreversible aggregation of the HAp NPs due to diminishing the repulsive forces between the particles. Deposition is further demonstrated on a commercial dental implant. Moreover, the adhesion of the coating satisfies FDA and international standard requirements. A porous interconnected network of bone‐like HAp layer is formed during soaking in a simulated body fluid for 30 d and is similar to bone generation, and it therefore holds promise for further in vivo testing.

Built‐In Electric Fields Dramatically Induce Enhancement of Osseointegration

“…[2,3] A growing number of implant modifica tion approaches to simulate biophysical and biochemical regulatory niches have been developed to facilitate bone forma tion. [4][5][6] However, ideal osseointegration remains a great challenge in clinic practice.…”

The electrochemical fabrication of hydrogels: a short review

“…3 [37]. The potential for new opportunities for constructing at the micro-and nano-scale is attracting increasing attention in a large range of potential applications, including synthesis of conducting polymers [38]; for use in regenerative medicine [39,40]; and the rapidly growing field of biosensors and microfluidic devices [41][42][43][44][45]; Electrochemically fabricated hydrogels can also be used to create antibacterial surfaces [46] and the coating of medical implants [47,48].…”

The future of electrochemical deposition: nanomaterial building blocks

“…We have recently developed different approaches, which we term "from nano to nano" [6][7][8][9][10][11]. The basic idea is to cause the destabilization of nanomaterials dispersed in a solution as a result of applying potential or current.…”