Pharmacomagnetography to evaluate the performance of magnetic enteric-coated tablets in the human gastrointestinal tract.

A magnetic enteric-coated tablet containing diclofenac sodium was produced, and its performance under physiological and disturbed gastrointestinal motility was assessed through pharmacomagnetography analysis. In vitro studies were performed using conventional methods and in vivo studies were conducted on healthy volunteers before (control) and after domperidone administration. The magnetic tablet's gastrointestinal (GI) transit and disintegration process were monitored using the Alternating Current Biosusceptometry sensors combined with drug plasmatic concentration. The Gastric Residence Time, Colon Arrival Time, Small Bowel Transit Time, Disintegration Time and the pharmacokinetics parameters were calculated. The pH-dependent polymers used to coat the magnetic tablets were able to avoid the premature drug release on gastric or small intestine simulated medium. Gastric Residence Time was accelerated compared with the control group (p < 0.01). No significant differences were found regarding small bowel transit, colon arrival, disintegration process, or pharmacokinetics parameters. A strong correlation between magnetic monitoring and pharmacokinetics parameters analysis was determinant to evaluate the efficiency in the drug delivery at a specific site in the human gastrointestinal tract. In addition, a tablet with a damaged coating was used as a proof of concept to show the suitability of our methodology to evaluate the tablet. Our study showed that pharmacomagnetography is a multi-instrumental approach towards assessing drug delivery and bioavailability.