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The effects of photodynamic therapy (PDT) are limited by the hypoxic tumor microenvironment (TME). In this paper, a new type of biocompatible multifunctional photosensitizer delivery system was fabricated to relieve tumor hypoxia and improve the efficacy of PDT. The photosensitizer hematoporphyrin monomethyl ether (HMME) and catalase (CAT) were encapsulated in the pores of mesoporous graphitic-phase carbon nitride nanosheets (mpg-C 3 N 4 ). Next, hyaluronic (HA) was coated on the surface of the mpg-C 3 N 4 via an amide linkage to construct the tumor-targeting HAase/CAT dual activatable and mpg-C 3 N 4 /HMME response photosensitizer delivery system (HA@mpg-C 3 N 4 -HMME/CAT). Upon intravenous injection, HA@mpg-C 3 N 4 -HMME/CAT shows high tumor accumulation owing to the tumor-targeting HA coating. Meanwhile, CAT within mpg-C 3 N 4 could trigger decomposition of endogenic TME H 2 O 2 to increase oxygen supply in-situ to relieve tumor hypoxia. This effect together with mpg-C 3 N 4 /HMME dual response is able to dramatically improve PDT efficiency. The hypoxia status of tumors was evaluated in vivo to demonstrate the success of the O 2 -supplying. And the in vitro and in vivo results showed the excellent therapeutic effect of the HA@mpg-C 3 N 4 -HMME/CAT photosensitizer delivery system. O 2 -supplying PDT may enable the enhancement of traditional PDT and future PDT design. [ABSTRACT FROM AUTHOR]

Although antibacterial activities of graphene oxide (GO) and its derivatives have been investigated comprehensively, their antifungal properties are still less reported. Yet, fungal contamination seriously threatens the public health. Herein, we present a design of graphene oxide-borneol (GOB) composite, and report its great antifungal effect. This GOB composite is prepared by esterification of borneol with thiomalic-acid-modified GO sheets, where the linker molecule is used to increase surface carboxyl groups. As a result, the antifungal activity displays a dramatically conversion from no activity of GO and its derivatives to distinct antifungal adhesion and growth inhibition of the GOB. Under microscopy, few spores can be found on the GOB surface, while large numbers of sporangia and spores adhere and grow on the control groups. It is also worth noting that on the GOB sample the fallen spore does not germinate even after 5 days, demonstrating a long-term antifungal effect of the GOB composite. Further studies confirm that carbon stereochemistry rather than wettability plays a crucial role on the antifungal adhesion properties. This study not only highlights a promising GOB composite as a candidate of graphene-based antifungal agent, but also provides us with in-depth understanding of the interactions between fungi and graphene-based materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Versatile nanoparticles for MMP2-triggered enhanced photo-immunotherapy. • Targeting tumor with HA-AuNR arouses ICD and activates antitumor immune response. • M2pep reverses immunosuppression by selectively depleting M2-TAMs. • This study provides a strategy to increase antitumor efficacy. Despite the potential of immunotherapy in various solid tumors, the efficiency of immunotherapy is limited by little tumor-infiltrating lymphocytes (TILs) and abundant immunosuppressive M2-type tumor-associated macrophages (M2-TAMs) in the tumor microenvironment (TME). Herein, we design a versatile photo-immunotherapy nanoparticle (termed as HA-AuNR/M-M2pep NP) to conquer above challenges. The HA-AuNR/M-M2pep NP is composed of hyaluronic acid modified gold nanorod (HA-AuNR) surface-modified with matrix metalloproteinase-2 (MMP2)-responsive M2pep fusion peptides (M-M2pep). Upon tumor site, the fabricated HA-AuNR/M-M2pep NP releases M2pep through the cleavage of MMP2-sensitive peptide to selectively deplete M2-TAMs and improve immunoactivity of TME. Meanwhile, HA-AuNR could target to tumor cells and realize precise tumor photothermal therapy (PTT) under near infrared light irradiation, which further triggers immunogenic cell death (ICD) of tumor cells and elicits antitumor immunity. In vivo antitumor studies reveal that HA-AuNR/M-M2pep NPs-mediated PTT and M2-TAMs depletion recruit TILs, activate effector T lymphocytes, secrete antitumor cytokines (e.g. IFN-γ, TNF-α), and effectively inhibit the growth of tumor. Collectively, HA-AuNR/M-M2pep NP-mediated photo-immunotherapy based on dual targeted delivery and bio-responsive drug release holds tremendous promise to enhance antitumor efficacy. [ABSTRACT FROM AUTHOR]