Abstract
We describe a low-power micro-actuator based on electroactive polymers - also called artificial muscles - to control the aperture area of a membrane. Using this device, the flux of drug molecules out of a depot can be influenced enabling time-resolved drug delivery patterns for individual or chronotherapeutic medication, e.g. in spastic or pain therapy. The depot can therefore either be constantly pressurized and the aperture area determines the outgoing flow rate, or the depot is kept pressureless enabling diffusion based transport of the drug molecules across the membrane. Measurements describing both modes of operation are presented. Flow rates of 0 and 4 µl/min at a depot pressure of 30 mbar and diffusion rates of 2.6 µg/h and 5.9 µg/h were determined for the “closed” and “open” state of the membrane, respectively. The low power consumption of less than 10 µW for freezing a state makes this “adjustable diffusion barrier (ADB)” an interesting alternative to existing valve concepts.
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References
Langer, R. (2003) Where a Pill Won’t Reach. Sci Am 288:50–57
LaVan D A, McGuire T, Langer R (2003) Small-scale systems for in vivo drug delivery. Nat Biotechnol 21:1184–1191
Deo S K, Moschou E A, Peteu S F et al. (2003) Responsive Drug Delivery Systems. Anal Chem A-Pages 75:207A–213A
Winkelmueller M, Winkelmueller W (1996) Long-term effects of continuous intrathecal opioid treatment in chronic pain of nonmalignant etiology. J Neurosurg 85:458–467
Zahavi A, Geertzen J H, Middel B et al. (2004) Long term effect (more than five years) of intrathecal baclofen on impairment, disability, and quality of life in patients with severe spasticity of spinal origin. J Neurol Neurosurg Psychiatry 75:1553–1557
Maloney J M, Uhland S A, Polito B F et al. (2005) Electrothermally activated microchips for implantable drug delivery and biosensing. J Control Release 109:244–255
Su Y, Lin L (2004) A Water-Powered Micro Drug Delivery System. Journal of Microelectomechanical Systems,13:75–82
Low L, Seetharaman S, He K, Madou M J (2000) Microactuators toward microvalves for responsive controlled drug delivery. Sens. Actuators B 67:149–160
Prescott J H, Lipka S, Baldwin S et al. (2006) Chronic, programmed polypeptide delivery from an implanted, multireservoir microchip device. Nat Biotechnol 24:437–438
Proos E R, Prescott J H, Staples M A (2008) Long term stability and in vitro Release of hPTH(1–34) from a Multi-reservoir Array, Pharm Res 25:1387–1395
Causley J et al. (2005) Electrochemically-induced fluid movement using polypyrrole. Synth Met 151:60–64
Smela E (2003) Conjugated Polymer Actuators for Biomedical Applications. Adv Mater 15:481–494
Smela E (1999) Microfabrication of PPy microactuators and other conjugated polymer devices. J Micromech Microeng 9:1–18
Jager E W H, Smela E, Inganäs O (1999) On-chip micoelectrodes for electochemnistry with moveable PPy bilayer actuators as working electodes. Sens Actuators B 56:73–78
Billat S, Kliche K, Gronmaier R et al. (2008) Monolithic integration of micro-channel on disposable flow sensors for medical applications. Sens Actuators A 145–146:66–74
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© 2009 Springer-Verlag Berlin Heidelberg
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Herrlich, S., Ziolek, S., Hoefemann, H., Zengerle, R., Haeberle, S. (2009). Adjustable Diffusion Barrier for Controlled Drug Release in Spastic and Pain Therapy. In: Vander Sloten, J., Verdonck, P., Nyssen, M., Haueisen, J. (eds) 4th European Conference of the International Federation for Medical and Biological Engineering. IFMBE Proceedings, vol 22. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-89208-3_568
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DOI: https://doi.org/10.1007/978-3-540-89208-3_568
Publisher Name: Springer, Berlin, Heidelberg
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