Jundong Shao

Ultrasmall Black Phosphorus Quantum Dots: Synthesis and Use as Photothermal Agents

Black phosphorus quantum dots (BPQDs) were synthesized using a liquid exfoliation method that combined probe sonication and bath sonication. With a lateral size of approximately 2.6 nm and a thickness of about 1.5 nm, the ultrasmall BPQDs exhibited an excellent NIR photothermal performance with a large extinction coefficient of 14.8 L g(-1) cm(-1) at 808 nm, a photothermal conversion efficiency of 28.4%, as well as good photostability. After PEG conjugation, the BPQDs showed enhanced stability in physiological medium, and there was no observable toxicity to different types of cells. NIR photoexcitation of the BPQDs in the presence of C6 and MCF7 cancer cells led to significant cell death, suggesting that the nanoparticles have large potential as photothermal agents.

Biodegradable black phosphorus-based nanospheres for in vivo photothermal cancer therapy

Photothermal therapy (PTT) offers many advantages such as high efficiency and minimal invasiveness, but clinical adoption of PTT nanoagents have been stifled by unresolved concerns such as the biodegradability as well as long-term toxicity. Herein, poly (lactic-co-glycolic acid) (PLGA) loaded with black phosphorus quantum dots (BPQDs) is processed by an emulsion method to produce biodegradable BPQDs/PLGA nanospheres. The hydrophobic PLGA not only isolates the interior BPQDs from oxygen and water to enhance the photothermal stability, but also control the degradation rate of the BPQDs. The in vitro and in vivo experiments demonstrate that the BPQDs/PLGA nanospheres have inappreciable toxicity and good biocompatibility, and possess excellent PTT efficiency and tumour targeting ability as evidenced by highly efficient tumour ablation under near infrared (NIR) laser illumination. These BP-based nanospheres combine biodegradability and biocompatibility with high PTT efficiency, thus promising high clinical potential.

Surface Coordination of Black Phosphorus for Robust Air and Water Stability

A titanium sulfonate ligand is synthesized for surface coordination of black phosphorus (BP). In contrast to serious degradation observed from the bare BP, the BP after surface coordination exhibits excellent stability during dispersion in water and exposure to air for a long period of time, thereby significantly extending the lifetime and spurring broader application of BP.

PLLA Nanofibrous Paper-Based Plasmonic Substrate with Tailored Hydrophilicity for Focusing SERS Detection

We report a new paper-based surface enhanced Raman scattering (SERS) substrate platform contributed by a poly(l-lactic acid) (PLLA) nanofibrous paper adsorbed with plasmonic nanostructures, which can circumvent many challenges of the existing SERS substrates. This PLLA nanofibrous paper has three-dimensional porous structure, extremely clean surface with good hydrophobicity (contact angle is as high as 133.4°), and negligible background interference under Raman laser excitation. Due to the strong electrostatic interaction between PLLA nanofiber and cetyltrimethylammonium bromide (CTAB) molecules, the CTAB-coated gold nanorods (GNRs) are efficiently immobilized onto the fibers. Such a hydrophobic paper substrate with locally hydrophilic SERS-active area can confine analyte molecules and prevent the random spreading of molecules. The confinement leads to focusing effect and the GNRs-PLLA SERS substrate is found to be highly sensitive (0.1 nM Rhodamine 6G and malachite green) and exhibit excellent reproducibility (∼8% relative standard deviation (RSD)) and long-term stability. Furthermore, it is also cost-efficient, with simple fabrication methodology, and demonstrates high sample collection efficiency. All of these benefits ensure that this GNRs-PLLA substrate is a really perfect choice for a variety of SERS applications.

Metabolizable Ultrathin Bi2Se3 Nanosheets in Imaging-Guided Photothermal Therapy

Poly(vinylpyrrolidone)-encapsulated Bi2 Se3 nanosheets with a thickness of 1.7 nm and diameter of 31.4 nm are prepared by a solution method. Possessing an extinction coefficient of 11.5 L g(-1) cm(-1) at 808 nm, the ultrathin Bi2 Se3 nanosheets boast a high photothermal conversion efficiency of 34.6% and excellent photoacoustic performance. After systemic administration, the Bi2 Se3 nanosheets with the proper size and surface properties accumulate passively in tumors enabling efficient photoacoustic imaging of the entire tumors to facilitate photothermal cancer therapy. In vivo biodistribution studies reveal that they are expelled from the body efficiently after 30 d. The ultrathin Bi2 Se3 nanosheets have large clinical potential as metabolizable near-infrared-triggered theranostic agents.

Black-Phosphorus-Incorporated Hydrogel as a Sprayable and Biodegradable Photothermal Platform for Postsurgical Treatment of Cancer

Abstract Photothermal therapy (PTT) is a fledgling therapeutic strategy for cancer treatment with minimal invasiveness but clinical adoption has been stifled by concerns such as insufficient biodegradability of the PTT agents and lack of an efficient delivery system. Here, black phosphorus (BP) nanosheets are incorporated with a thermosensitive hydrogel [poly(d,l‐lactide)‐poly(ethylene glycol)‐poly(d,l‐lactide) (PDLLA‐PEG‐PDLLA: PLEL)] to produce a new PTT system for postoperative treatment of cancer. The BP@PLEL hydrogel exhibits excellent near infrared (NIR) photothermal performance and a rapid NIR‐induced sol–gel transition as well as good biodegradability and biocompatibility in vitro and in vivo. Based on these merits, an in vivo PTT postoperative treatment strategy is established. Under NIR irradiation, the sprayed BP@PLEL hydrogel enables rapid gelation forming a gelled membrane on wounds and offers high PTT efficacy to eliminate residual tumor tissues after tumor removal surgery. Furthermore, the good photothermal antibacterial performance prevents infection and this efficient and biodegradable PTT system is very promising in postoperative treatment of cancer.

Near-infrared light-triggered drug delivery system based on black phosphorus for in vivo bone regeneration

A near-infrared (NIR) light-triggered drug delivery platform is produced by incorporating SrCl2 and BP nanosheets (BPs) into poly(lactic-co-glycolic acid) (PLGA) for bone regeneration. The fabricated BP-SrCl2/PLGA microspheres show efficient NIR absorption and photothermal effects due to the BPs. The NIR-triggered release behavior of Sr2+ by flawing the PLGA shells is investigated and the microspheres exhibit excellent cell viability and biodegradability. Implantation of the BP-SrCl2/PLGA microspheres into a rat femoral defect demonstrates good tissue compatibility and excellent bone regeneration capacity under NIR light irradiation. Our study indicates that local release of Sr2+ at optimal time periods controlled by NIR irradiation improves bone regeneration significantly and this NIR-triggered drug delivery system composed of BPs is suitable for therapies requiring precise control at specific time.

2D Material-Based Nanofibrous Membrane for Photothermal Cancer Therapy

One of the clinical challenges facing photothermal cancer therapy is health risks imposed by the photothermal nanoagents in vivo. Herein, a photothermal therapy (PTT) platform composed of a 2D material-based nanofibrous membrane as the agent to deliver thermal energy to tumors under near-infrared (NIR) light irradiation is described. The photothermal membrane, which is fabricated by an electrospinning poly(l-lactic acid) (PLLA) nanofibrous membrane loaded with bismuth selenide (Bi2Se3) nanoplates, exhibits very high photothermal conversion efficiency and long-term stability. Cell experiments and hematological analyses demonstrate that the Bi2Se3/PLLA membranes have excellent biocompatibility and low toxicity. PTT experiments performed in vivo with the Bi2Se3/PLLA membrane covering the tumor and NIR irradiation produce local hyperthermia to ablate the tumor with high efficiency. Different from the traditional systematical and local injection techniques, this membrane-based PTT platform is promising in photothermal cancer therapy, especially suitable for the treatment of multiple solid tumors or skin cancers, and long-term prevention of cancer recurrence after surgery or PTT, while eliminating the health hazards of nanoagents.

Photothermal Therapy: Metabolizable Ultrathin Bi2 Se3 Nanosheets in Imaging-Guided Photothermal Therapy (Small 30/2016).

Ultrathin Bi2 Se3 nanosheets are prepared by a solution method. As described on page 4136 by X.-F. Yu, Q.-Q. Wang, P. K. Chu, and co-workers, such ultrathin Bi2 Se3 nanosheets exhibit strong near infrared (NIR) light absorption, excellent photothermal and photoacoustic performance, enabling efficient imaging-guided photothermal therapy. Furthermore, these Bi2 Se3 nanosheets are well metabolized. These attractive properties render the Bi2 Se3 nanosheets promising as a NIR-triggered theranostic agents in cancer therapies.