Paper Title
A PH-Sensitive No-Generating Carrier For Attenuating Inflammatory Responses

Abstract
Inflammation is a kind of defensive system that body can respond to various stimuli such as infection or irritation. Physiologically, inflammation is regarded as a protective mechanism; however, long-term inflammation has been known to cause many diseases such as osteoarthritis, cancer, and diabetes. Inflammation is highly related to overproduction of reactive oxygen species (ROS).Thus, preventing excess ROS is crucial for attenuating inflammatory responses.Previous studies indicate that nitric oxide (NO) is able to quench ROS. Nevertheless, its short half-life restricts the clinical application. Herein, this studydeveloped a pH-responsive NO-generating microsphere, with a PLGA shell and anaqueous core that contained an NO donor and a surfactant molecule. Under inflammatory acidic environment, the NO donor decomposed and generated NO bubbles. The surfactant molecule then stabilizedNO bubbles, preventing their breakdown and increasing their activity. These preserved NO further quenched ROS and attenuated inflammatory responses. This novel delivery platform provides a new strategy for treating inflammatory diseases. Index Terms - Inflammation; ROS; nitric oxide; pH-responsiveness