Membranes Used in Drug Delivery Walter Trachim BMCB6583/2/12

Introduction Membrane-based drug delivery systems have been developed for a number of reasons Membrane-based drug delivery systems have been developed for a number of reasons Size Size Timing Timing Bioavailability Bioavailability Different types of delivery systems exist and are used in different applications Different types of delivery systems exist and are used in different applications

Membrane- Based Delivery A number of different membrane-based delivery systems exist. They include: A number of different membrane-based delivery systems exist. They include: Liposome Liposome Liposome/Nanoparticle Hybrid Liposome/Nanoparticle Hybrid PLGA PLGA

Delivery Systems Liposomes – Single or multiple lipid bi-layers arranged in concentric circles designed to contain an aqueous solution Liposomes – Single or multiple lipid bi-layers arranged in concentric circles designed to contain an aqueous solution Reliable : Reliable : Biocompatible Biocompatible Biodegradable Biodegradable Can be scaled, or their size can be modified Can be scaled, or their size can be modified Considerably lower toxicity levels Considerably lower toxicity levels

Delivery Systems PLGA – Polylactide-co-glycolide PLGA – Polylactide-co-glycolide Pros Pros Biocompatible Biocompatible Versatile – will encapsulate a wide variety of medications Versatile – will encapsulate a wide variety of medications Able to “tune” how drug is released Able to “tune” how drug is released Cons Cons Can be inefficient at low pH Can be inefficient at low pH Degraded easily in acid environments Degraded easily in acid environments

Membrane-Based Delivery Liposome-Nanoparticle Hybrids Liposome-Nanoparticle Hybrids Can be hydrophilic (encapsulated in the liposome) or hydrophobic (embedded in the lipid bilayer) Can be hydrophilic (encapsulated in the liposome) or hydrophobic (embedded in the lipid bilayer) Used primarily for diagnostic testing – imaging is a common application (PET, MRI) Used primarily for diagnostic testing – imaging is a common application (PET, MRI) Also used for chemotherapy, mainly as a guard against cytotoxicity Also used for chemotherapy, mainly as a guard against cytotoxicity

Membrane-Based Delivery Liposome – Quantum Dot Hybrids Liposome – Quantum Dot Hybrids Semiconductors – have fluorescent qualities Semiconductors – have fluorescent qualities Used for optically-based diagnostic applications Used for optically-based diagnostic applications Also used for chemotherapy – less prone to leakage Also used for chemotherapy – less prone to leakage LD found to be favorable for pulmonary imaging LD 50 found to be favorable for pulmonary imaging

Applications Cancer treatment – chemotherapy Cancer treatment – chemotherapy Pain management Pain management Time-release Time-release Anti-hypertensives Anti-hypertensives Anti-depressants Anti-depressants Sleep aids Sleep aids

References Al-Jamal, W., & Kostarelos, K. (2011). Liposomes: From a Clinically Established Drug Delivery System to a Nanoparticle Platform for Theranostic Nanomedicine. Accounts of Chemical Research, 44(10), doi: /ar200105p Al-Jamal, W., & Kostarelos, K. (2011). Liposomes: From a Clinically Established Drug Delivery System to a Nanoparticle Platform for Theranostic Nanomedicine. Accounts of Chemical Research, 44(10), doi: /ar200105p Samstein, R., Perica, K., Balderrama, F., Look, M., Fahmy, T. (2007). The use of deoxycholic acid to enhance the oral bioavailability of biodegradable nanoparticles. Biomaterials, 29, doi: /j.biomaterials Samstein, R., Perica, K., Balderrama, F., Look, M., Fahmy, T. (2007). The use of deoxycholic acid to enhance the oral bioavailability of biodegradable nanoparticles. Biomaterials, 29, doi: /j.biomaterials Wieber, A., Selzer, T., Kreuter, J. (2011). Characterisation and stability studies of a hydrophilic decapeptide in different adjuvant drug delivery systems: A comparative study of PLGA nanoparticles versus chitosan-dextran sulphate micriparticles versus DOTAP-liposomes. International Journal of Pharmaceutics, 421, doi:/ j.ijpharm Wieber, A., Selzer, T., Kreuter, J. (2011). Characterisation and stability studies of a hydrophilic decapeptide in different adjuvant drug delivery systems: A comparative study of PLGA nanoparticles versus chitosan-dextran sulphate micriparticles versus DOTAP-liposomes. International Journal of Pharmaceutics, 421, doi:/ j.ijpharm