Two-Photon Photoexcited Photodynamic Therapy and Contrast Agent with Antimicrobial Graphene Quantum Dots

Abstract

A graphene quantum dot (GQD) used as the photosensitizer with high two-photon absorption in the near-infrared region, a large absolute cross section of two-photon excitation (TPE), strong two-photon luminescence, and impressive two-photon stability could be used for dual modality two-photon photodynamic therapy (PDT) and two-photon bioimaging with an ultrashot pulse laser (or defined as TPE). In this study, a GQD efficiently generated reactive oxygen species coupled with TPE, which highly increased the effective PDT ability of both Gram-positive and -negative bacteria, with ultralow energy and an extremely short photoexcitation time generated by TPE. Because of its two-photon properties, a GQD could serve as a promising two-photon contrast agent for observing specimens in depth in three-dimensional biological environments while simultaneously proceeding with PDT action to eliminate bacteria, particularly in multidrug-resistant (MDR) strains. This procedure would provide an efficient alternative approach to easily cope with MDR bacteria.

Two‐Photon‐Excited Silica and Organosilica Nanoparticles for Spatiotemporal Cancer Treatment

“…The potential of 3D‐resolved two‐photon‐actuated nanomedicine has been exploited via various nanomaterials such as semiconductor and carbon nanodots, polymeric, organic, silicon, gold, graphene and graphene oxide, silica hybrid, and other inorganic nanomaterials. What are the advantages of silica‐based nanoparticles?…”

Photosensitizers for Two‐Photon Excited Photodynamic Therapy

“…The advantages of using nanocarriers lie in their excellent colloid dispersity in water, which enables the solubilization of hydrophobic PSs in physiological conditions and an enhanced accumulation of PSs at tumor sites through an enhanced permeability and retention effect . The currently reported nanoparticles for 2PE‐PDT mainly include carbon‐, silica‐, or gold‐based nanoparticles, semiconductor quantum dots (QDs), and nonconjugated polymer nanostructures …”

Amino-Functionalized Nitrogen-Doped Graphene-Quantum-Dot-Based Nanomaterials with Nitrogen and Amino-Functionalized Group Content Dependence for Highly Efficient Two-Photon Bioimaging

“…This finding was confirmed through an uptake assay. The nanomaterial-Ab EGFR -treated cancer cells exhibited oxidative stress independent of reactive oxygen species (ROS) under TPE, as determined using singlet oxygen sensor green (SOSG), trans-1-(2 -methoxyvinyl)pyrene (t-MVP), 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5carboxanilide (XTT), and glutathione (γ-L-glutamyl-L-cysteinyl-glycine, GSH) probes ( Table 3 as well as Supplementary Tables S2 and S3) [29][30][31][32][33][34][35]. The aforementioned result was consistent with the signal of 1 O 2 phosphorescence at 1270 nm emitted from the amino-N-GQD-polymers ( Figure 7).…”

“…The Ti:sapphire femtosecond laser (Tsunami, Spectra-Physics, Santa Clara, CA, USA) optical system with a pulse width of less than 100 fs and a repetition rate of 80 MHz, an inverted optical microscope (Axiovert 200, Zeiss, Oberkochen, Germany), a x-y galvanometer scanner (6215H, Cambridge, MA, USA), a triple-axis sample-positioning stage (ProScan TM II, Prior Scientific Instruments Ltd., Cambridge, UK), a z-axis piezoelectric nano-positioning stage (Nano-F100, Mad City Labs, Madison, WI, USA), an acousto-optic modulator (AOM) (Neos 23080-x-1.06-LTD, BMI Surplus Inc., Hanover, MA, USA), photomultiplier tubes (PMTs) (H5783P, Hamamatsu, Shizuoka Prefecture, Japan), and a data acquisition (DAQ) card with a field-programmable gate array (FPGA) module (PCI-7831R, National Instruments, Austin, TX, USA). The optical system was used according to the previous studies [29,[41][42][43].…”