title: Fabrication of indocyanine green encapsulated biodegradable microbubbles for structural and functional imaging of cancer.
abstract: We developed a novel dual-modal contrast agent for the structural and functional imaging of cancer. The contrast agent was fabricated by encapsulating indocyanine green (ICG) in poly(lactic-co-glycolic acid) (PLGA) microbubbles using a modified double-emulsion method. More stabilized absorption and fluorescence emission characteristics were observed for aqueous and plasma suspensions of ICG-encapsulated microbubbles. The technical feasibility of concurrent structural and functional imaging was demonstrated through a series of benchtop tests in which the aqueous suspension of ICG-encapsulated microbubbles was injected into a transparent tube embedded in an Intralipid phantom at different flow rates and concentrations. Concurrent fluorescence imaging and B-mode ultrasound imaging successfully captured the changes of microbubble flow rate and concentration with high linearity and accuracy. One potential application of the proposed ICG-encapsulated PLGA microbubbles is for the identification and characterization of peritumoral neovasculature for enhanced coregistration between tumor structural and functional boundaries in ultrasound-guided near-infrared diffuse optical tomography.
authors: The Ohio State University, Department of Biomedical Engineering, 270 Bevis Hall, 1080 Carmack Road, Columbus, Ohio 43210, USA. xu.202@osu.edu
authors: Ronald X
authors: RX
authors: Xu
authors: Jiwei
authors: J
authors: Huang
authors: Jeff S
authors: JS
authors: Xu
authors: Duxin
authors: D
authors: Sun
authors: George H
authors: GH
authors: Hinkle
authors: Edward W
authors: EW
authors: Martin
authors: Stephen P
authors: SP
authors: Povoski
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D003952:Diagnostic Imaging / Q000379:methods*; D007208:Indocyanine Green / Q000737:chemistry*; D019344:Lactic Acid / Q000737:chemistry*; D016014:Linear Models; D045423:Microbubbles; D009369:Neoplasms / Q000175:diagnosis*; D019047:Phantoms, Imaging; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D013050:Spectrometry, Fluorescence / Q000379:methods; D019265:Spectroscopy, Near-Infrared / Q000379:methods; D014463:Ultrasonography / Q000379:methods
chemical_list: D001672:Biocompatible Materials; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D007208:Indocyanine Green