Session 2C: Inaugural Lectures by Fellows/Associates

Biomaterial Strategies To Overcome Barriers For Drug Delivery

Drug delivery strategies have the potential to increase the bioavailability of drugs and penetrate across anatomical barriers to reach deeper target tissues. Biodegradable and trigger responsive biomaterials act as platforms for the design of efficient drug delivery carriers. Biomimetic, trigger responsiveness, nanosize based penetration, site specific self-assembly and sol–gel transitions act as platform strategies to design smart biomaterials specifically suited for drug delivery in various systems. Several examples of these strategies and their translation will be covered in the talk. Amphiphilic phospholipid nanovesicles mimic the pulmonary surfactant and can be optimized to form respirable aerosols with deep penetration into the alveoli with non-invasive nebulization techniques. These act as platforms for antioxidant, anti-inflammatory and anticancer drugs with synergistic pulmonary surfactant actions for therapy in acute respiratory distress syndrome and pulmonary metastasis respectively. Transdermal delivery requires strategies to pass through the ceramide rich stratum corneum barrier. Nanoparticles of fluidizing phospholipids and fatty acids can be modulated to alter bilayer packing and act as platforms to pass through the stratum corneum, or pass along the follicular route for dermal and systemic effects. Stabilization of the platform in oils has led to micronutrient loaded infant massage oils containing multivitamins and iron for neonatal development, leveraging traditional practices of infant massage with nanotechnology. Nanoparticle in biopolymeric microneedle platforms having conical morphology pass through the stratum corneum to form dermal depots for sustained release of drugs. Ultrasound responsive biomaterials consisting of sulphur hexafluoride loaded microbubbles linked to drug loaded lipopolymeric nanoparticles undergo cavitation in the presence of an ultrasound trigger. This phenomenon can be utilized for triggered drug release while the contrast enhancing property produces theranostic advantages for site specific therapy in cancers. Another barrier for drug delivery to the central nervous system is the blood brain barrier. Nanoparticle in slow degrading amphiphilic in situ gels act as depot formulations for postsurgical delivery of chemotherapeutics in glioblastoma with minimal systemic accumulation. Miltefosine based lipid nanoparticles that are mucoadhesive and stable nasal fluid, can exploit the intranasal route along the olfactory nerves for direct nose to brain delivery. The urothelium of the urinary bladder poses another challenge to delivery of drugs to the urinary bladder. Intravesical delivery is limited by decreased retention and urinary excretion and poor penetration through the urothelium. Nanoparticle in in situ gels which are stable in variable pH and in the presence of urine are optimized for enhanced penetration through the urothelium. The platforms have potential in superficial bladder carcinoma, deep muscle penetrating stages and interstitial cystitis for enhanced effectiveness over several weeks. Core shell trigger responsive nanoparticles for posterior segment ocular drug delivery and for sequential delivery of multiple drugs are also explored. Nanocomposite gels have been developed that act as quick hemostatic, multifunctional agents for trauma care with hemostatic, antibacterial and wound healing properties. The talk will highlight some of these technologies, the strategies underlying the innovations and their translation.