Abstract

Multi-functional nanoparticles are garnering considerable attention for their applications in nanomedicine due to their unique capabilities. Notably, nanoparticles can be engineered to deliver a specific compound at a controlled rate, to spatially target a particular location, and even to remotely destroy cells once the particles have reached their destination. Additionally, highly specific functionalities can be incorporated into the particles including fluorescence, magnetic properties, light scattering, and drug delivery. In many cases, biomolecules (e.g. antibodies, oligonucleotides, or peptides) are bound to the particle surface to direct the particle to a specific location or target. Circulation times can be lengthened by protecting the particles with a stealth coating enabling the particles to avoid the body’s scavenging mechanisms, and many nanoparticles can be tracked within the body to study their capabilities and behaviors in vivo. This presentation will highlight recent advances in the development of two unique nanomedicinal particle platforms including poly (D,L-lactide-co-glycolic acid) (PLGA) and mesoporous silica nanoparticles (MSN). PLGA is a biodegradable polymer commonly used to make particles for in vivo studies and is generally regarded as safe. PLGA is approved by both the US Food and Drug Administration (FDA) and European Medicine Agency (EMA) for use in vaccines, drug delivery, and tissue engineering. Key advantages of MSN are associated with their high surface area and facile surface tunability. Often described as “nanosponges,” MSN can adsorb large amounts of molecules dissolved in solution thanks to this high surface area. Synthesis and characterization for these advanced nanomaterials will be discussed, and the presentation will demonstrate their utility as drug delivery vehicles and targeted therapeutic platforms. Both types of nanoparticles are currently used as potential prophylactic vaccines against HIV (NIH grants); MSN with enlarged pore size have been designed to encapsulate message RNA coding for envelop protein of the virus (glycoprotein, gp160). In addition, their surface has been modified to specifically target a family of professional antigen presenting cells (APC), namely the dendritic cells. Transcription of the particles by the cells as well as the translation of their genetic content has been proven in vitro. PLGA particles encapsulating another variant of the envelop protein (gp140) have been prepared, their surface has been decorated with the same envelop protein in order to activate and prolong the immune response.