Figure 13.

(A) Schematic illustration of inhalable particles as carriers for delivery of drug loaded nanoparticles to the deep lung. (B) Scanning microscopic images of microparticles made from mannitol and leucine using a spray-drying process. The microparticles were loaded with nanoparticles made from glyceryl monostearate and soybean phosphatidylcholine with a double emulsion process. (C) A zoomed-in image of (B). (D) Fluorescence images of lungs from untreated rat (E) and rat after intrapulmonary delivery of microparticles fluorescein-labeled nanoparticles. (F) Schematic illustration of a nanoparticle-hydrogel hybrid (NP-gel) system with tissue adhesive properties for localized antibiotic delivery under flow conditions. In this design, dopamine methacrylamide (DMA) containing catechol functional group was conjugated into gel matrix for adhesion. (G) NP-gel was tested for adhesion under a flow (shear stress = 3.2 Pa) on E. coli bacterial film (green: nanoparticles in the gel; bacteria: red), HEK 293T cell monolayer (blue: cell nuclei; green: nanoparticles in the gel), and shaved mouse skin. (H) E. coli biofilm formation when the bacteria were treated with PBS, blank gel (gel without nanoparticles or ciprofloxacin), free ciprofloxacin, ciprofloxacin loaded nanoparticles (without hydrogel), and ciprofloxacin-loaded NP-gel (scale bar = 5 mm). Reprinted from Advanced Drug Delivery Reviews, Vol 127, Gao W, Chen Y, Zhang Y, Zhang Q, Zhang L, Nanoparticle-based local antimicrobial drug delivery, Pages No.46–57, Copyright (2018), with permission from Elsevier.¹⁸⁴