New developments in the field of Drug Release instrumentation.

I J BRUVERA; BEA SANZ; G. F. GOYA; A. TORO-CÓRDOVA

Barcelona

Conferencia; NanoBio&Med2018; 2018

Phantoms Foundation

A large number of nanotechnology-based drug delivery systems (DDS) are reported every year in the scientific literature. However, only a tiny fraction of these innovative approaches reaches pre-clinical or clinical phase studies. Different nanocarriers and release methods have shown good therapeutic efficiency at in vitro and in vivo levels, and some of those have proven positive therapeutic results in humans. From silica-based porous nanoparticles to liposomes or polymeric nanoparticles, new products commercially available already include nanovectors as drug carriers, and these new systems need to be characterized accordingly. Non-invasive strategies for remotely triggering drug release have been proposed mainly for liposomalbased nanovectors. [1] These strategies can be based on different triggering stimuli, including (but not restricted to) enzymatic [2], temperature [3], light [4] , magnetic fields [5] and ultrasound. [6] Of special clinical interest is the control of drug release profiles on demand by a remote alternating magnetic field of low frequency (i.e., at the low part of the RF spectrum, 100 ? 800 kHz), because of the deep penetration of these waves without noticeable interaction with biological tissues. In a collaborative effort between the Magnetic Hyperthermia Group and nB Nanoscale Biomagnetics S.L., we developed a new device (see Figure 1) capable of remote triggering and in situ quantification of therapeutic drugs, whenever a magnetically-responsive material need to be tested. Some examples are hydrogels (made of alginates, PNIPAAm, etc.) or functionalized MNPs as drug carriers. The heating efficiency of these materials can be measured by their specific power absorption (SPA) values, concurrently with the kinetics profiles of drug release. The rates of drug release of any thermo-responsive material can be further controlled through application of AC magnetic field, using a time-modulated set of pulses to release the desired amount of drug. After several tests of standard thermoresponsive materials loaded with B12 vitamin as a concept drug, the outcome has shown good control of the kinetics profiles by time and field exposure. For example, using calibration methods before experiments, a time-pulse programming was applied to ferrogels samples to control the kinetic releaseprofiles. Under these conditions, the device was able to detect amounts of drug released as tiny as 5- 12(1) ng, demonstrating its potential for highprecision real-time quantitative control of drug release.