Remote magnetic switch off microgate for nanofluidic drug delivery implants Marco Farina 1,2 & Andrea Ballerini 1,3 & Gianluca Torchio 1,2 & Giulia Rizzo 1,2 & Danilo Demarchi 2 & Usha Thekkedath 1 & Alessandro Grattoni 1 # Springer Science+Business Media New York 2017 Abstract In numerous pathologies, implantable drug deliv- ery devices provide advantages over conventional oral or par- enteral approaches. Based on the site of implantation and re- lease characteristics, implants can afford either systemic de- livery or local administration, whereby the drug is delivered at or near the site of intended action. Unfortunately, current im- plantable drug delivery systems provide limited options for intervention in the case of an adverse reaction to the drug or the need for dosage adjustment. In the event that drug delivery must be terminated, an urgent surgical retrieval may be the only reliable option. This could be a time sensitive and costly effort, requiring access to trained professionals and emergency medical facilities. To address such limitations, here we dem- onstrate, in vitro and ex vivo, a novel microsystem for the rapid and effective switch off of drug delivery from an im- plantable nanofluidic system, by applying a safe external elec- tromagnetic field in the FDA approved dose range. This study represents a proof of concept for a technology with potential for broad applicability to reservoir-based delivery implants for both complete interruption or remote titration of drug administration. Keywords Drug Delivery . Implantable Device . Remote control . Electromagnetic field 1 Introduction In the treatment of chronic pathologies, implantable drug de- livery systems offer significant advantages compared to the conventional oral administration or injections. Implants can achieve sustained and controlled drug release, eliminating Brollercoaster^ effect in drug concentration in the blood and eliminate issues associated with patient compliance to the therapeutic regimen (Ainslie and Desai 2008). Additionally, next-generation devices are enabling electronic control and remote management of drug release providing telemedical means to healthcare workers and patients (Santini et al. 2000; Nguyen et al. 2013; Meng and Hoang 2012; Tikka et al. 2011). However, in the event of an adverse patient reaction to the drug, a malfunction of the delivery system or a failure of electronic compo- nents leading to drug overdosing, emergency surgical ex- plantation remains the only option for ceasing drug re- lease. Even in the case of subcutaneous placement, device extraction requires trained personnel and specialized med- ical facilities, which may not be at reach. A non-surgical external deactivation of the implantable system could allow minimally-trained personnel, or the pa- tients themselves, to safely halt drug release quickly and ef- fectively, giving the flexibility and additional time to reach a medical facility for further intervention. There are numerous implantable drug delivery technologies under development and a few are progressing through regulatory pathway (Safari and Zarnegar 2014). Among these, some adopt micro-nanofluidics to create miniaturized systems to regulate the administration of pharmacologically active compounds for long periods (Fine et al. 2013; Ferrati et al. 2013). Similar devices have been explored for clinical applications in cardio- vascular and chronic disorders such as diabetes, hormone re- placement therapy, mental illnesses, and cancer, among others * Alessandro Grattoni agrattoni@houstonmethodist.org 1 Department of Nanomedicine, Houston Methodist Research Institute, 6670 Bertner Avenue, R8-216, Houston, TX 77030, USA 2 Department of Electronics and Telecommunications, Politecnico di Torino, Torino, Italy 3 Department of Oncology and Onco-Hematology, University of Milan, Milan, Italy Biomed Microdevices (2017) 19:42 DOI 10.1007/s10544-017-0180-5