Fluorescence emission mechanism for the π-conjugated zwitterion 2,4-Bisimidazolylphenol base on ESIPT: A TDDFT theoretical reconsideration.

Molecules with zwitterionic characteristics exhibit significant potential for utilization in nonlinear optics, optoelectronics, and organic lasers owing to their large dipole moments. Recently, the synthesized compound 2,4-bis (4,5-diphenyl-1H-imidazol-2-yl) phenol (2,4-bImP) by Sakai et al. has been noticed for its unique photochromic properties in solvents [J.

Short-Range Charge Transfer in DNA Base Triplets: Real-Time Tracking of Coherent Fluctuation Electron Transfer.

The short-range charge transfer of DNA base triplets has wide application prospects in bioelectronic devices for identifying DNA bases and clinical diagnostics, and the key to its development is to understand the mechanisms of short-range electron dynamics. However, tracing how electrons are transferred during the short-range charge transfer of DNA base triplets remains a great challenge. Here, by means of ab initio molecular dynamics and Ehrenfest dynamics, the nuclear-electron interaction in the thymine-adenine-thymine (TAT) charge transfer process is successfully simulated.

Reconsideration of the ESIPT off mechanism for fluorescent probe MNC in aqueous solution.

Fluorescent probes with excited state intramolecular proton transfer (ESIPT) properties play a significant role in the research of life science and material science. Guo et al. designed 3-hydroxy-2-(6-Methoxynaphthalen-2-yl)-4H-chromen-4-one (MNC) as a control to achieve the dual-color fluorescence imaging of lipid droplets and endoplasmic reticulum (ER).

ESIPT mechanism of triple emission with hydroxy-oxadiazole compound in DMSO: A theoretical reconsideration.

The compound in solvents with triple fluorescence feature of excited state intramolecular proton transfer (ESIPT) has a broad prospect in fluorescent probes, dye sensors and molecular synthesis of photosensitive dyes. An ESIPT molecule hydroxy-bis-2,5-disubstituted-1,3,4-oxadiazoles (compound 1a) emits two fluorescence peaks in dichloromethane (DCM) and three fluorescence peaks in dimethyl sulfoxide (DMSO). [Dyes and Pigments 197 (2022) 109927].

Turn-on stimuli-responsive switch: strategies for activating a new fluorescence channel by pressure.

The stimulus-responsive smart switching of aggregation-induced emission (AIE) features has attracted considerable attention in 4D information encryption, optical sensors and biological imaging. Nevertheless, for some AIE-inactive triphenylamine (TPA) derivatives, activating the fluorescence channel of TPA remains a challenge based on their intrinsic molecular configuration. Here, we took a new design strategy for opening a new fluorescence channel and enhancing AIE efficiency for (E)-1-(((4-(diphenylamino)phenyl)imino)methyl)naphthalen-2-ol.

The dynamical temporal behaviors of guanine-cytosine coherent charge transfer.

The vibrational coupling between the nucleus and electrons is an important factor in determining the ultrafast charge transfer rate of DNA biological systems. However, in most typical DNA base pairs like the guanine-cytosine (G-C) base pair, the vibrational coupling of ultrafast coherent charge transfer has been largely ignored. Here, we simulate the nucleus-electron interaction in the coherent charge transfer of G-C using molecular dynamics and Ehrenfest dynamics.

Turning enol* emission of SBOH via restricting twisted intramolecular charge transfer behavior by pressure.

Stimuli-responsive luminogens with aggregation-induced emission and excited state intramolecular proton transfer (ESIPT) properties have applications in storage devices, anti-counterfeiting, imaging, and sensors. Nevertheless, group rotation appears in twisted intramolecular charge transfer (TICT) state, resulting in decreased fluorescence intensity. Inhibiting TICT remains a challenge based on their intrinsic molecular configuration.

Exploring the effect of nitrile substituent position on fluorescence quantum yield of ESIPT-based oxazoline derivatives: A TDDFT investigation.

We explore the mechanism specifically on quantum yields difference of 2-(4,4-Dimethyl-4,5-dihydrooxazol-2-yl)-3-hydroxybenzonitrile (1-CN) and 4-(4,4-Dimethyl-4,5-dihydrooxazol-2-yl)-3-hydroxybenzonitrile (3-CN) by density functional theory and time-dependent density functional theory within the Tamm-Dancoff approximation. The structures optimization and the potential energy curves scanning of singlet excited state directly prove that the excited state intramolecular proton transfer (ESIPT) can take place in 1-CN and 3-CN molecules. The calculated spectra show that the fluorescence peaks of two molecules come from the emission of keto* configuration.

Förster resonance energy transfer outpaces Auger recombination in CdTe/CdS quantum dots-rhodamine101 molecules system upon compression.

Förster resonance energy transfer (FRET) and Auger recombination in quantum dots (QDs)-molecules system are important mechanisms for affecting performance of their optoelectronic and photosynthesis devices. However, exploring an effective strategy to promote FRET and suppress Auger recombination simultaneously remains a daunting challenge. Here, we report that FRET process is promoted and Auger recombination process is suppressed in CdTe/CdS QDs-Rhodamine101 (Rh101) molecules system upon compression.

Structural basis of fullerene derivatives as novel potent inhibitors of protein acetylcholinesterase without catalytic active site interaction: insight into the inhibitory mechanism through molecular modeling studies.

Acetylcholinesterase (AChE) is an important kind of esterase that plays a key biological role in the central and peripheral nervous systems. Recent research has demonstrated that some fullerene derivatives serve as a new nanoscale class of potent inhibitors of AChE, but the specific inhibition mechanism remains unclear. In the present article, several molecular modeling methods, such as molecular docking, molecular dynamics simulations and molecular mechanics/generalized Born surface area calculations, were used for the investigation of the binding mode and inhibition mechanism of fullerene inhibitions for AChE.

Insight into the process of product expulsion in cellobiohydrolase Cel6A from Trichoderma reesei by computational modeling.

Glycoside hydrolase cellulase family 6 from Trichoderma reesei (TrCel6A) is an important cellobiohydrolase to hydrolyze cellooligosaccharide into cellobiose. The knowledge of enzymatic mechanisms is critical for improving the conversion efficiency of cellulose into ethanol or other chemicals. However, the process of product expulsion, a key component of enzymatic depolymerization, from TrCel6A has not yet been described in detail.

[The optimization of method for lentiviral vector to transfect CD34+ hematopoietic stem cells from human cord].

Objective: To identify the best transfect conditions for lentiviral vector to transfect CD34+ stem cells from human cord blood.

Methods: CD34+ hematopoietic stem cells from human cord blood were transduced with pTRIPdU3-RNAiTALh-EF1a-GFP plasmid expressing GFP by the second generation and third generation lentiviral vector system. The transfect conditions such as the concentration of the virus, polybrene, transfect volume and media, multiplicity of infection (MOI) values, incubating time and centrifugation in 12-well plate at 200 x g were tested to obtain optimal transfect conditions.