Copper sulfide (CuS) nanodisks have tunable and directionally localized surface plasmon resonance excitation in the near infrared spectrum suggesting that they may be suitable as photoacoustic (PA) imaging contrast agents. To investigate the PA characteristics and cytotoxicity for in vivo imaging, CuS nanodisks were prepared by solvent based synthesis followed by surface modification with poly(ethylene glycol) methyl ether thiol (PEG-thiol, Mw=1000). The size (diameter=31.1±7.45 nm, aspect ratio= 4.54±1.51 nm) and uniformity of CuS nanodisks were measured under scanning transmission electron microscope (Figure a). The synthesized CuS sample was diluted with ethanol and prepared in small tubing (ID=0.85 mm, OD=1.27 mm) placed in parallel for PA scanning. Figure b shows the ultrasound (grey) and PA (red) signal of the tubing. At isomolar concentrations, the CuS nanodisk has a stronger and more stable PA signal than gold nanorod (GNR)—a standard PA contrast agent. At a concentration of 1.25 nM, CuS offered 2.3-fold better signal than GNR at 700 nm (near maximum GNR absorption), where the maximum PA signal of CuS nanodisks occurs at 950 nm. The CuS signal was more stable over 10 minutes of excitation at 700 nm; the GNR decreased by 11 % (P&lt;0.001) (Figure c). In addition, cell viability assays revealed little impact; 95 % of ovarian cancer cells were viable after being incubated with CuS nanodisk at 5 nM for 24 hours (n=8, p&lt;0.03) (Figure d).

Copper sulfide nanodisks are photoacoustic imaging contrast agents

251st National Meeting (2016)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.