Microfluidic Fabrication of Gadolinium-Doped Hydroxyapatite for Theragnostic Applications

Abstract

Among the several possible uses of nanoparticulated systems in biomedicine, their potential as theragnostic agents has received significant interest in recent times. In this work, we have taken advantage of the medical applications of Gadolinium as a contrast agent with the versatility and huge array of possibilities that microfluidics can help to create doped Hydroxyapatite nanoparticles with magnetic properties in an efficient and functional way. First, with the help of Computational Fluid Dynamics (CFD), we performed a complete and precise study of all the elements and phases of our device to guarantee that our microfluidic system worked in the laminar regime and was not affected by the presence of nanoparticles through the flow requisite that is essential to guarantee homogeneous diffusion between the elements or phases in play. Then the obtained biomaterials were physiochemically characterized by means of XRD, FE-SEM, EDX, confocal Raman microscopy, and FT-IR, confirming the successful incorporation of the lanthanide element Gadolinium in part of the Ca (II) binding sites. Finally, the magnetic characterization confirmed the paramagnetic behaviour of the nanoparticles, demonstrating that, with a simple and automatized system, it is possible to obtain advanced nanomaterials that can offer a promising and innovative solution in theragnostic applications.

Tackling current production of HAp and HAp-driven biomaterials

“…149 Stirred tank batch reactors and microreactors are used to carry out doped HAp synthesis. 150,151 However, doping ions can affect the nucleation and growth kinetics or crystallization dynamics, leading to alterations in the final morphology of HAp particles. 152,153 Hence, on one hand, the size and shape of the particles may be tuned by adjusting the concentration of the doping metal ions; on the other hand, it sets up an obstacle toward the production of HAp particles with the same morphology and size with different doping ratios.…”

Synthesis and Characterization of Hydrogel Droplets Containing Magnetic Nano Particles, in a Microfluidic Flow-Focusing Chip

“…The control of the size, shape, and polydispersity along with the precise generation and repeatability of droplet operations, have made a droplet-based microfluidic system a potent high throughput platform for biomedical research and applications. In addition to being used as micro reactors, droplet-based systems have also been used to directly synthesize particles and encapsulate many biological entities for biomedicine and biotechnology applications [ 18 , 19 ].…”

In Vivo Assessment of High-Strength and Corrosion-Controlled Magnesium-Based Bone Implants

“…Among the different coating techniques used, micro arc oxidation (MAO) is one of the most successful processes to create a coating layer that is tightly bonded to the Mg alloy substrate with a porous surface morphology that allows for the deposition of subsequent coating layers as needed [24,26,30]. This can be beneficial when the inclusion of nanomaterials of different elements to the implant's surface is required, such as hydroxyapatite, gadolinium, or iron/zinc [31,32].…”