Bio-Inspired Surface Modification of Magnetite Nanoparticles with Dopamine Conjugates

Abstract

Organically-coated nanomaterials are intensively studied and find numerous applications in a wide range of areas from optics to biomedicine. One of the recent trends in material science is the application of bio-mimetic polydopamine coatings that can be produced on a variety of substrates in a cost-efficient way under mild conditions. Such coatings not only modify the biocompatibility of the material but also add functional amino groups to the surface that can be further modified by classic conjugation techniques. Here we show an alternative strategy for substrates modification using dopamine conjugates instead of native dopamine. Compared to the classic scheme, the proposed strategy allows separation of the “organic” and “colloidal” stages, and simplified identification and purification steps. Modification with pre-modified dopamine made it possible to achieve high loading capacities with active components up to 10.5% wt. A series of organo-inorganic hybrids were synthesized and their bioactivity was analyzed.

Preparation of stable colloidal dispersion of surface modified Fe3O4 nanoparticles for magnetic heating applications

“…Several studies have recently reported on the modification of the surface of magnetite nanoparticles and improvement of their properties for various applications, including: collection of spilled oils on the earth’s surface 25 , removal of coomassie brilliant blue-R250 dye (CBB) from aqueous solutions 26 , dye absorption 27 , inhibiting hen egg-white lysozyme (HEWL) fibrillization and destroying mature fibrils 28 . Polyamines 25 , multifunctional pyridinium ionic liquids 26 , citric acid 28 , trisodium citrate 28 , dopamine conjugates 29 , oleic acid and polyacrylic acid 30 were utilized in these studies to modify the surface of nanoparticles. Using different agents to modify the surface of nanoparticles yields unique properties, such as the ability to reuse magnetite nanoparticles modified with polyamines 25 , increasing the absorption of coomassie brilliant blue-R250 dye (CBB) from aqueous solutions from 84.4 mg/g in case of nanoparticles without surface modification to more than 700 mg/g in case of surface modified magnetite nanoparticles 26 , The increase in dye absorption from 60% for nanoparticles without surface modification to 98% for those modified with citric acid and the effect on their anti-amyloid potential 27 , improving bioreactivity with dopamine conjugates 29 , and the increase in dispersibility in aqueous environments by surface modification using polyacrylic acid 30 , the significantly increased stability in saline water and the creation of hydrophobic properties with surface modification using oleic acid 31 are all examples of these outcomes.…”

MOF-808 on Polyacrylonitrile Nanofibers for Degradation of Chemical Warfare Agents

“…The process is simple, environmentally friendly, and cost-effective. Moreover, the rich functionality of PDA provides many active sites for subsequent modification of the substrate; thus, PDA has received considerable attention. − For example, Nuo Xu et al deposited PDA on the surface of carbon fiber (CF) and exploited the strong adhesion to prepare the CF-PDA@Ag composite material with greatly improved mechanical properties; Dan Song et al utilized the strong adhesion of the PDA coating, abundant catechol functional groups, and the binding ability of horseradish peroxidase to prepare the MCNCs@PDA nanocomposite, which had an ultrahigh adsorption capacity …”

The Influence of Magnetic Fields on Electrophoretic Processes in Magnetic Colloids with Different Stabilization Mechanisms

“…Since they are more stable and retain aggregative stability for a long time, they are widely applied in engineering and instrumentation [15][16][17][18]. In recent years, interest has shifted to the electrophoretic properties of water-based colloidal systems and their possible applications for magnetic drug delivery methods or medical diagnostics [19][20][21][22][23]. Electrophoretic systems are used for the creation of magnetic coatings for microelectronics [24], the deposition of protective coatings [25], heat transfer systems [26], electronic-paper displays [27], microfluidic devices [28,29], and bioanalytical assays [30][31][32].…”