Xiaoxiao Tan

MoS2 Quantum Dot@Polyaniline Inorganic–Organic Nanohybrids for in Vivo Dual-Modal Imaging Guided Synergistic Photothermal/Radiation Therapy

In this study, we introduce a versatile nanomaterial based on MoS2 quantum dot@polyaniline (MoS2@PANI) inorganic-organic nanohybrids, which exhibit good potential to not only enhance photoaccoustic (PA) imaging/X-ray computed tomography (CT) signal but also perform efficient radiotherapy (RT)/photothermal therapy (PTT) of cancer. Upon the intravenous injection of MoS2@PANI hybrid nanoparticles, the in vivo tumor could be precisely positioned and thoroughly eliminated under the PA/CT image-guided combination therapy of PTT/RT. This versatile nanohybrid could show good potential to facilitate simultaneously dual-modal imaging and synergetic PTT/RT to realize better anticancer efficiency.

Indocyanine Green-Loaded Silver Nanoparticle@Polyaniline Core/Shell Theranostic Nanocomposites for Photoacoustic/Near-Infrared Fluorescence Imaging-Guided and Single-Light-Triggered Photothermal and Photodynamic Therapy

Photoacoustic (PA)/near-infrared fluorescence (NIRF) dual-modal imaging-guided phototherapy has been wide explored very recently. However, the development of high-efficiency and simplified-performed theranostic system for amplifying imaging-guided photothermal therapy/photodynamic therapy (PTT/PDT) is still a great challenge. Herein, a single-light-triggered indocyanine green (ICG)-loaded PEGylation silver nanoparticle core/polyaniline shell (Ag@PANI) nanocomposites (ICG-Ag@PANI) for PA/NIRF imaging-guided enhanced PTT/PDT synergistic effect has been successfully constructed. In this study, the synthesized Ag@PANI nanocomposites are utilized not only as the promising photothermal agent but also as potential nanovehicles for loading photosensitizer ICG via π-π stacking and hydrophobic interaction. The as-prepared ICG-Ag@PANI possesses many superior properties such as strong optical absorption in the near-infrared (NIR) region, enhanced photostability of ICG, as well as outstanding NIR laser-induced local hyperthermia and reactive oxygen species (ROS) generation. In the in vivo study, PA/NIRF dual-modal imaging confirms the accumulation and distribution of ICG-Ag@PANI in the tumor region via enhanced permeability and retention (EPR) effect. Moreover, the PTT effect of ICG-Ag@PANI rapidly raised the tumor temperature to 56.8 °C within 5 min. It is also demonstrated that the cytotoxic ROS generation ability of ICG is well maintained after being loaded onto Ag@PANI nanocomposites. Remarkably, in comparison with PTT or PDT alone, the single 808 nm NIR laser-triggered combined PTT/PDT therapy exhibits enhanced HeLa cells lethality in vitro and tumor growth inhibition in vivo.

An efficient dual-loaded multifunctional nanocarrier for combined photothermal and photodynamic therapy based on copper sulfide and chlorin e6.

The therapeutic effectiveness of photodynamic therapy (PDT) was hampered by the poor water solubility and instability in physiological conditions of the photosensitizers. Here, we designed folate conjugated thermosensitive liposomes (TSL) as the nanocarrier to improve the solubility, stability and biocompatibility of photosensitizer Chlorin e6 (Ce6). Based on the photothermal effect, we combined copper sulfide (CuS) as the photothermal agent to realize heat-triggered Ce6 release as well as synergistic effect of photothermal and photodynamic therapy. In vitro MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed that Ce6-CuS-TSL had low dark toxicity, while performed excellent phototoxicity under the combined 660 and 808 nm laser irradiation compared to any single laser irradiation alone. Moreover, in vivo combination therapy study revealed that Ce6-CuS-TSL inhibited tumor growth to a great extent without evident side effect under the laser irradiation. All detailed evidence demonstrated a considerable potential of Ce6-CuS-TSL for synergistic cancer treatment.

Dual-Modal Imaging-Guided Theranostic Nanocarriers Based on Indocyanine Green and mTOR Inhibitor Rapamycin.

The development of treatment protocols that resulted in a complete response to photothermal therapy (PTT) was usually hampered by uneven heat distribution and low effectiveness. Here, we reported an NIR fluorescence and photoacoustic dual-modal imaging-guided active targeted thermal sensitive liposomes (TSLs) based on the photothermal therapy agent Indocyanine green (ICG) and antiangiogenesis agent Rapamycin (RAPA) to realize enhanced therapeutic and diagnostic functions. As expected, the in vitro drug release studies exhibited the satisfactory result of drug released from the TSLs under hyperthermia conditions induced by NIR stimulation. The in vitro cellular studies confirmed that the FA-ICG/RAPA-TSLs plus NIR laser exhibited efficient drug accumulation and cytotoxicity in tumor cells and epithelial cells. After 24 h intravenous injection of FA-ICG/RAPA-TSLs, the margins of tumor and normal tissue were accurately identified via the in vivo NIR fluorescence and photoacoustic dual-modal imaging. In addition, FA-ICG/RAPA-TSLs combined with NIR irradiation treated tumor-bearing nude mice inhibited tumor growth to a great extent and possessed much lower side effects to normal organs. All detailed evidence suggested that the theranostic TSLs which were capable of enhancing the therapeutic index might be a suitable drug delivery system for dual-modal imaging-guided therapeutic tools for diagnostics as well as the treatment of tumors.

Photosensitizer loaded PEG-MoS2–Au hybrids for CT/NIRF imaging-guided stepwise photothermal and photodynamic therapy

In this study, we developed X-ray computed tomography (CT)/near-infrared fluorescence (NIRF) imaging for visually guiding the photothermal therapy (PTT)/photodynamic therapy (PDT) of antitumor nanocomposites (PEG-MoS2-Au-Ce6), by adsorbing chlorin e6 (Ce6) to the gold nanoparticle (AuNPs)-decorated molybdenum disulfide (PEG-MoS2) nanosheets. The NIR photosensitizer Ce6 was adsorbed onto the PEG-MoS2-Au hybrids viaπ-π stacking and hydrophobic interactions, where Ce6 remained in its quenched state due to the surface plasmon resonance (SPR) capacity of AuNPs, as well as the coupling interaction with PEG-MoS2 nanosheets. However, Ce6 was dequenched and boosted strong NIR fluorescence signals after being released from the surface of PEG-MoS2-Au hybrids upon heat generation, thus producing the PDT effect for anti-tumor therapy. Moreover, the PEG-MoS2 nanosheets and Ce6 in the PEG-MoS2-Au-Ce6 nanocomposites could be further used for CT and NIRF dual-modal imaging, respectively. In vitro NIR-triggered drug release studies indicated that the PEG-MoS2-Au-Ce6 nanocomposites rapidly release the drug around the tumor site under the photothermal effect. Therefore, this dual-modality nanosystem simultaneously enables precise cancer diagnosis and therapy.

Theranostic liposomes containing conjugated polymer dots and doxorubicin for bio-imaging and targeted therapeutic delivery

This work was devoted to the development of a lipid-based theranostic nanoparticle able to simultaneously host conjugated polymer dots, doxorubicin (Dox) and folate acid (FA). Poly(9,9-dioctylfluorene-2,7-diyl-co-benzothiadiazole) (PFBT) was chosen as the fluorescent probe because of its high brightness in in vitro cellular uptake studies and good biocompatibility in in vitro/in vivo toxicity experiments. The theranostic liposomes (PFBT–Dox–Lip–FA) exhibited a hydrodynamic size of 127.30 ± 3.20 (nm) with a zeta potential of −25.00 ± 2.00 (mV). Mostly importantly, the extent of Dox release at 24 h from PFBT–Dox–Lip–FA showed a satisfactory result under mild hyperthermia conditions compared with Dox–Lip–FA. Such rapid release led to a lower half maximal inhibitory concentration (IC50) in MCF-7 cells at 16.8 ± 4.5 (μg mL−1), whereas the IC50 of Dox–Lip–FA (37 °C) was 28.3 ± 3.7 (μg mL−1). The cellular uptake study also revealed higher drug accumulation in tumor cells for theranostic liposomes. In vivo studies of PFBT–Dox–Lip–FA on tumor-bearing mouse models revealed that the distribution of liposomes in the tumors could be indicated accurately by PFBT. Besides, tumor-bearing mice could be significantly inhibited by PFBT–Dox–Lip–FA. Together with its negligible in vivo toxicity, PFBT–Dox–Lip–FA is a useful system for simultaneous cancer diagnosis and targeted drug delivery.

Hollow Au-Cu Nanocomposite for Real-Time Tracing Photothermal/Antiangiogenic Therapy

High absorption in the near-infrared (NIR) region is essential for a photoabsorbing agents to realize efficient photothermal therapy (PTT) for cancer. Here, a novel hollow Au-Cu nanocomposite (HGCNs) is developed, which displays a significantly enhanced NIR surface plasmon resonance absorption and photothermal transduction efficiency. Besides, fluorescent polymer dots poly(9,9-dioctylfluorene-2,7-diyl-co-benzothiadiazole) (PFBT) and chemotherapeutic mammalian target of rapamycin (mTOR) inhibitor agent rapamycin (RAPA) are attached onto the HGCNs (RAPA/PFBT-HGCNs) for real-time NIR fluorescence tracing and combined PTT/antiangiogenesis therapy. In particular, due to the fluorescence resonance energy transfer effect, RAPA/PFBT-HGCNs can act as NIR-activatable on/off probe system for real-time tracing of tumor tissues. A standard in vitro cellular uptake study, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, dual-staining study, and flow cytometry assay reveal that the RAPA/PFBT-HGCNs combined with NIR laser exhibit higher drug accumulation and cytotoxicity in both tumor cells and epithelial cells. Moreover, the margins of tumor and normal tissue can be accurately indicated by NIR-stimulated dequenched PFBT after 24 h intravenous administration. Further, tumor growth can be considerably hampered by the optimal formulation plus laser treatment with relatively lower side effects. Consequently, the work highlights the real-time tracing and enhanced PTT/antiangiogenesis therapy prospects of the established HGCNs with tremendous potential for treatment of cancer.

CHAPTER 2:Image-guided Drug Delivery Systems Based on NIR-absorbing Nanocarriers for Photothermal-chemotherapy of Cancer

In recent years, great efforts have been given to researching multifunctional nanoagents that combine diagnostic and therapeutic functions for highly efficient and low toxicity antitumor treatments. In particular, combining real-time imaging with spatially precise photothermal therapy mediated by nanoparticles responsive to near-infrared (NIR, λ = 700–1100 nm) light through conversion of photo energy into heat has attracted interest due to its simplicity, safety and noninvasiveness, as well as targeting and remote-control properties. Apart from being directly utilized for image guided photothermal ablation of cancer, the photothermal effect of NIR-absorbing organic nanomaterials has also been exploited for remotely controlled drug release. This photothermal-controlled drug delivery system provides promising approaches to reverse multidrug resistance, for which the poor cellular uptake and insufficient intracellular drug release remain the rate-limiting steps for reaching the drug concentration level within the therapeutic window. In this chapter, we will systematically discuss the latest progress in the development of organic and inorganic nanocarriers used as a photothermal-controlled drug delivery system for the combined photo-chemotherapy of cancer. Various types of NIR-absorbing nanocarriers developed for the delivery of drugs, as well as image-guided combined photothermal-chemotherapies, will be reviewed. The final section will address the future prospects and challenges in this rapidly growing field.