Thermoresponsive hollow magnetic microspheres with hyperthermia and controlled release properties

Abstract

Thermoresponsive hollow magnetic microspheres consisting of a hollow magnetic core, a carbon shell, and a smart polymer layer are presented in this article. A carbon nanomaterial was used as a steric stabilizer for Fe 3 O 4 nanoparticles and a supporter for polymer. The thermoresponsive monomer, N-isopropyl acrylamide, was grafted on the carbon-encapsulate hollows by surface radical polymerization. The experimental results indicate that the composites had a phase-transition temperature around 438C and a saturation magnetization of 56.9 emu/g; this showed apparent thermosensitivity and magnetism. The performances in hyperthermia evaluated by an inductive magnetic field showed that the hybrid microspheres had a specific absorption rate of 240 W/g. The model drug, 5-fluorouracil, was loaded in and released from the microspheres with different release rates at 35 and 508C. This demonstrated that the as-synthesized microspheres had a thermotriggered release ability and would be a good drug carrier in the biomedical field.

Thiophene Derivatives as Anticancer Agents and Their Delivery to Tumor Cells Using Albumin Nanoparticles

“…It was noticeable that the particle size was ~170 nm by TEM, smaller than the average size determined by DLS (205.4 ± 3.44 nm) at 25 °C. This was because DLS showed HSA nanoparticles in the hydrated state, while TEM displayed particle size in the dried state [28,29]. A favorable stability of TP 5 -NPs was ensured in the study of stability for 72 h in vitro, which can prolong retention of TP 5 -NPs in tumor tissue [30].…”

Fabrication and evaluation of controllable core/shell magnetic molecular imprinted polymers based on konjac glucomannan for trichlorfon

“…As shown in Figure (d), EDS demonstrated that Fe 3 O 4 contained more Fe and less C. The Fe signal consisted of the characteristic peaks of the magnetite nanoparticles, and the less intense C signal might originate from the carbon‐coated copper grid . The N signal as shown in Figure (e,f) was assigned to the graft monomer (AM), which proved that the polymer shell was successfully coated on the surface of the Fe 3 O 4 nanoparticles . In addition, the results showed that the amount of N increased with increasing monomer dose, which further indicated that controllable core/shell structures could be successfully generated.…”

Remotely actuated polymeric nanocomposites for biomedical applications

“…Other applications such as microrheology applications [34,157], lab-on-a-chip systems [158], drug delivery [98,159], hyperthermia [160,161] and microfluidics/mixing by applying a sinusoidal #» B of 30 mT and a frequency of 20 Hz, obtaining a mixing efficiency of ≈ 80% and an increment in efficiency to 95% by reducing the frequency to 5 Hz [150].…”