Magnetically induced drug release from niosome-based nanocarriers loaded with doxorubicin

Niosomes co-loaded with doxorubicin and magnetic nanoparticles were synthesised using the thin film hydration method. The loading efficiency of the doxorubicin was between 60-70%. The hydrodynamic diameter measured as the average number (mean ± standard deviation), using dynamic light scattering, was found to be 188 ± 68 nm, 141 ± 86 nm and 169 ± 69 nm for the plain niosomes, niosomes loaded with doxorubicin and niosomes loaded with doxorubicin and magnetic nanoparticles, respectively. The zeta potential for all three niosome samples was determined to be −26.4 mV ± 1.9 mV. The thermally mediated release of doxorubicin was monitored using fluorescence spectroscopy and found to follow 1st order kinetics. The rate constant for the thermal release was 1.2 × 10⁻⁶, 1.0 × 10⁻⁴ and 5.1 × 10⁻⁴ min⁻¹ at 298, 313 and 333 K, respectively. The doxorubicin was also released using an alternating magnetic field, this also followed 1st order kinetics and had a rate constant of 1.7 × 10⁻² min⁻¹. This is four orders of magnitude greater than the thermal release at the same temperature (298 K). The work shows the magnetically controlled, burst release from a drug-loaded niosome delivery system. The release was triggered on demand by the application of the alternating magnetic field, resulting in 86% doxorubicin release within 3 hours compared to 3% release in 30 days via thermal release.