First-principles calculations of 0D/2D GQDs-MoS mixed van der Waals heterojunctions for photocatalysis: a transition from type I to type II.

The fabrication of type II heterojunctions is an efficient strategy to facilitate charge separation in photocatalysis. Here, mixed dimensional 0D/2D van der Waals (vdW) heterostructures (graphene quantum dots (GQDs)-MoS) for generating hydrogen from water splitting are investigated based on density functional theory (DFT). The electronic and photocatalytic properties of three heterostructures, namely, CH-MoS, CH-MoS and CH-MoS are estimated by analyzing the density of states, charge density difference, work function, Bader charge, absorption spectra and band alignment.

Theoretical insights on type I/II photoreactions of potential Zn(II) polypyridyl photosensitizers for two-photon photodynamic therapy.

Large two-photon absorption cross-sections are vital to photosensitizers (PSs) in TP-PDT, which can be used to develop in-depth treatment for diseased cells and minimize the harm to surrounding cells. Here, we conduct a study about photophysical properties of one Ru(II) polypyridyl complex and two designed Zn(II) polypyridyl complexes by means of DFT and TD-DFT methods. The main results are as follows: firstly, the two-photon absorption spectrum of two designed complexes Zn-OMe and Zn-OCOOCH are all within the phototherapeutic window (550-900 nm).

Theoretical insight into the photophysical properties of long-lifetime Ir(iii) and Rh(iii) complexes for two-photon photodynamic therapy.

Two-photon photodynamic therapy (TP-PDT) plays crucial roles in curing tumors because it involves deep penetration of drugs into the tissue and has minimal damage to the surrounding cells. Our theoretical study was aimed at providing fresh insights into photosensitizers, such as [Ir(N^C)2(N^N)]+ (N^C = 2-phenylpyridine, N^N = bis-benzimidazole) and [Rh(N^C)2(N^N)]+, to treat cancer via the TP-PDT route. To better understand the properties of the complexes [Ir(N^C)2(N^N)]+ and [Rh(N^C)2(N^N)]+, the one-photon and two-photon absorption electronic spectra, energy gap (ΔES-T), strength of two-photon absorption cross-section (δ), spin-orbit matrix element (S1|ĤSO|Tj), and phosphorescence lifetimes (τ) were calculated by DFT and TD-DFT.

Theoretical study on photophysical properties of three high water solubility polypyridyl complexes for two-photon photodynamic therapy.

Two-photon photodynamic therapy (TP-PDT) is a very promising treatment that has drawn much attention in recent years due to its ability to penetrate deeper into tissues and minimize the damage to normal cells. Here, the properties of three highly water soluble Ru(ii) and Zn(ii) polypyridyl complexes as photosensitizers (PSs) were examined, including the one-photon and two-photon absorption (OPA and TPA) spectra, singlet-triplet energy gap (ΔH-L), TPA cross-section and spin-orbit coupling constant via Density Function Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT). Their potential therapeutic use as photosensitizers in TP-PDT is proposed, where the reasoning is as follows: first, they possess strong absorption in the therapeutic window; second, the vertical excitation energy is greater than 0.

A theoretical study of a series of water-soluble triphenylamine photosensitizers for two-photon photodynamic therapy.

In this study, the therapeutic activity of a series of water-soluble triphenylamine (TP) photosensitizers (Ps) was explored by using theoretical simulations. The key photophysical parameters which determined the efficiency of Ps, such as absorption electronic spectra, singlet-triplet energy gaps and spin-orbit matrix elements were calculated at density functional theory and its time-dependent extension (DFT, TD-DFT). The calculated results showed that these TP photosensitizers possessed large two-photon absorption cross-section in the near-infrared region (NIR), efficient intersystem crossing (ISC) transition from the first singlet excited state to the low lying triplet excited states and sufficient energy for generating reactive oxygen species (ROS).

[Reconstructive approaches of alimentary canal for subtotal gastrectomy].

Objective: To explore the optimal technique of digestive tract reconstruction for radical proximal gastrectomy.

Methods: The clinical data for 120 cases of proximal gastric cancer undergoing radical proximal gastrectomy at our hospital from 2000 to 2009 were analyzed retrospectively. They included three approaches of digestive tract reconstruction.