PMC

In vitro ultrasound contrast-enhanced images in a latex tube (a) US images of various concentrations of PPyHMs; (b) Normalized US intensities over PPyHMs concentration; (c) Time-dependent echogenic behaviors of PPyHMs at the concentration of 20 mg mL⁻¹. In vivo ultrasonograms in the rabbit right kidney (d) pre- and (e) post-administration of PPyHMs.

(a) Schematic illustration of the formation of echogenic PPyHMs for combined US imaging and PTT via a facile O/W microemulsion method; SEM and ultrathin-section TEM images of obtained PPyHMs with (b) PVP and (c) PVA as stabilizers; (d) UV-vis-NIR spectra of various concentrations PPyHMs dispersed in RPMI-1640 culture medium, inset was the photograph for various concentrations of PPyHMs dispersed in RPMI-1640 culture medium, indicating good dispersibility; (e) Heating curves of PPyHMs in RPMI-1640 culture medium at different concentrations under 808 nm laser irradiation.

Photothermal destruction of U87-MG cells with or without PPyHMs and NIR laser (808 nm, 6 W cm⁻²) treatments (a, b, c, d, e and f). White circle indicates the laser spot; live/dead stain for viability shows dead cells as red while viable cells as green; (g) Cell viability of HUVECs with 24 h exposure to various concentrations of PPyHMs; (f) U87-MG cell viability after treatment with different concentrations of PPyHMs and NIR laser for different irradiation time.

(a) IR thermal images of tumor-bearing mice with and without PPyHMs injection exposed to the NIR laser at the power density of 0.64 W cm⁻² recorded at different time intervals. (b) contrast-enhanced ultrasonograms after the intratumoral injection of PPyHMs (0.2 mL, 2 mg mL⁻¹) into the mice from PPyHMs + laser group for visualization of the agent distribution to guide the following PTT (tumors are highlighted in the red circles). (c) The tumor growth curves of different groups of mice after PTT treatment. The tumor volumes were normalized to their initial sizes. (d) Representative photographs of mice bearing U87-MG tumors after various different treatments indicated. (e) H&E stained tumor slices collected from different groups of mice immediately after laser irradiation. The PPyHMs injected tumor was severely damaged after laser irradiation.