Rationale:: Matrix metalloproteinases (MMPs)–mediated extracellular matrix destruction is the major cause of development and progression of abdominal aortic aneurysms. Systemic treatments of MMP inhibitors have shown effectiveness in animal models, but it did not translate to clinical success either because of low doses used or systemic side effects of MMP inhibitors. We propose a targeted nanoparticle (NP)–based delivery of MMP inhibitor at low doses to the abdominal aortic aneurysms site. Such therapy will be an attractive option for preventing expansion of aneurysms in patients without systemic side effects. Objective:: Our previous study showed that poly( d , l -lactide) NPs conjugated with an antielastin antibody could be targeted to the site of an aneurysm in a rat model of abdominal aortic aneurysms. In the study reported here, we tested whether such targeted NPs could deliver the MMP inhibitor batimastat (BB-94) to the site of an aneurysm and prevent aneurysmal growth. Methods and Results:: Poly( d , l -lactide) NPs were loaded with BB-94 and conjugated with an elastin antibody. Intravenous injections of elastin antibody–conjugated BB-94-loaded NPs targeted the site of aneurysms and delivered BB-94 in a calcium chloride injury-induced abdominal aortic aneurysms in rats. Such targeted delivery inhibited MMP activity, elastin degradation, calcification, and aneurysmal development in the aorta (269% expansion in control versus 40% elastin antibody–conjugated BB-94-loaded NPs) at a low dose of BB-94. The systemic administration of BB-94 alone at the same dose was ineffective in producing MMP inhibition. Conclusions:: Targeted delivery of MMP inhibitors using NPs may be an attractive strategy to inhibit aneurysmal progression.

In this research, we have investigated the photocatalytic degradation of carbon-coated TiO2 nanoparticles in polypropylene-based nano-composites. For this purpose, polypropylene-based nano-composites were prepared using carbon-coated TiO2 nanoparticles and commercially available TiO2 nanoparticles (Degussa, P25). Our results from SEM, FTIR, and tensile tests showed that the photocatalytic property of TiO2 causes chain scission reactions, crosslinking and consequently photocatalytic degradation of polypropylene that affects the mechanical properties of exposed nano-composites. We have observed that with greater carbon content of the TiO2 nano-powders, there is less photocatalytic degradation.