Article
Biochemistry & Molecular Biology
Piotr Hanczyc, Przemyslaw Slota, Czeslaw Radzewicz, Piotr Fita
Summary: Two-photon excitation combined with the effect of light amplification provides a sensitive method for detecting amyloids of different forms. This study demonstrates the detection of amyloid structures using two-photon excited amplified spontaneous emission in brain tissue infiltrated with various amyloid phantoms. The relatively simple extension of currently used emission-based optical spectroscopy techniques can provide key information on pathogenic amyloid structures in tissue.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY
(2022)
Article
Optics
Sandro Heuke, Carla Silva Martins, Remi Andre, Loic Legoff, Herve Rigneault
Summary: Two-photon excited fluorescence (2PEF) microscopy is a popular nonlinear imaging method for biomedical samples. It uses multiple detectors and spectral filter sets to discriminate different fluorophores based on their emission behavior. However, 2PEF suffers from the loss of fluorescence photons outside the filter transmission range and may fail to discriminate fluorophores with similar emission profiles. Here, we propose an alternative 2PEF method that discriminates fluorophores based on their excitation spectra.
Article
Chemistry, Applied
Zhen Chen, Chenghu Dai, Qian Zhou, Huitian Du, Jihui Fan, Shenghao Han, Chuang Zhang, Zhiyong Pang
Summary: Exciplex-based TADF materials exhibit excellent optical properties by converting non-radiative states to radiative states, showing potential for nonlinear optical applications.
Article
Chemistry, Physical
Yu Wang, Mengtao Sun, Lingyan Meng
Summary: The high-order nonlinearity enables larger signal enhancements in two-photon spectroscopy compared to one-photon spectroscopy, important for conducting photoluminescence measurements at the single molecule level. Theoretical investigation on two-photon-excited fluorescence (2pF) of monolayer MoS2 in various tip-enhanced spectroscopy configurations achieved large enhancement factor on the order of 10^5 by optimizing tip parameters. Calculations of radiative and nonradiative decay rates further elucidated the 2pF emission mechanism.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Shi-Cheng Wang, Qiang-Sheng Zhang, Zheng Wang, Lin Zheng, Xiao-Dong Zhang, Ya-Nan Fan, Peng-Yan Fu, Xiao-Hong Xiong, Mei Pan
Summary: By designing a ligand with reduced symmetry, two alkaline-earth metal-based MOFs with dense packing structures and low porosity were obtained. The desolvated MOFs exhibited high quantum yields and excellent two-photon excited photoluminescence, while maintaining external-stimuli-responsive properties suitable for anticounterfeit fields.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Analytical
Yuchi Cheng, Huangmei Zhou, Jinming Xu, Yu Zhao, Xihang Chen, Rodolphe Antoine, Meng Ding, Kun Zhang, Sanjun Zhang
Summary: A two-photon excited ratiometric fluorescent pH sensor was developed by combining L-cysteine-protected AuNCs (Cys@AuNCs) with fluorescein isothiocyanate (FITC). The sensor showed a large dynamic range for pH measurement and had potential for sensitive quantitation of pH in living cells under two-photon excitation. In addition, the synthesized Cys@AuNCs exhibited excellent photoactivated peroxidase-like activity, promising for rapid colorimetric biosensing and control of catalytic reactions by photostimulation.
Article
Chemistry, Medicinal
Xue-Li Hao, Ai-Min Ren, Liang Zhou
Summary: Hydrogen sulfide (H2S) has important physiological and pathological roles, but abnormal levels can cause diseases. Researchers have explored the mechanism of a turn-on probe for H2S monitoring and investigated the effect of geometric modifications on optical properties. They found that introducing electron-withdrawing substituent groups in benzopyran can suppress molecular skeleton vibration and improve two-photon absorption (TPA) ability, making it a potential material for biological imaging and H2S detection.
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2023)
Article
Chemistry, Applied
Huitian Du, Chenghao Liu, Yuan Yu, Jing Li, Shenghao Han, Zhiyong Pang
Summary: In this study, a donor-spacer-acceptor (D-spacer-A) system with strong one-/two-photon excited fluorescence properties was constructed and the observed fluorescence properties were attributed to the utilization of long-range exciplex states, based on comprehensive analysis of photoluminescence spectra, PL transient decay curves, PL quantum yield values, and transient absorption measurements. This work contributes to the understanding of long-range exciplex states in D-spacer-A exciplex TADF systems.
Article
Chemistry, Multidisciplinary
Dan Li, Xiangquan Deng, Zhourui Xu, Deliang Wang, Gaixia Xu, Pingyu Zhang, Ping Qiu, Weixin Xie, Dong Wang, Ben Zhong Tang, Ke Wang
Summary: Molecular engineering was used to develop an NIR-II fluorescence probe, DCTBT, for deep-brain two-photon imaging. DCTBT showed good biocompatibility, high photostability, bright NIR-II emission, and a large two-photon fluorescence action cross section at the 1700 nm excitation window. It achieved imaging depths of 2180 and 1135 μm in mouse brain with removed and intact skull, respectively, surpassing all existing probes and imaging modalities. DCTBT labeling also enabled hemodynamic imaging of blood flow with a depth of 714 μm in mouse brain vessels with the intact skull.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Analytical
Attila Csomos, Ervin Kovacs, Miklos Madarasz, Flora Zsofia Fedor, Anna Fulop, Gergely Katona, Balazs Rozsa, Zoltan Mucsi
Summary: A library of fluorescent GFP chromophore based chemosensors (GFZnPs) was prepared for the detection of Zn2+ using two-photon microscopy. These sensors exhibit high selectivity, excellent water solubility, and wide pH-range usability, making them one of the best two-photon probes for Zn2+.
SENSORS AND ACTUATORS B-CHEMICAL
(2024)
Article
Physics, Multidisciplinary
Jakob Hinney, Adarsh S. Prasad, Sahand Mahmoodian, Klemens Hammerer, Arno Rauschenbeutel, Philipp Schneeweiss, Juergen Volz, Max Schemmer
Summary: The study explores quadrature squeezing observed in a weak guided light field transmitted through an ensemble of atoms coupled to an optical nanofiber. By measuring the squeezing spectrum, direct access to the phase and amplitude of the energy-time entangled part of the two-photon wave function is obtained. The research provides a diagnostic tool for quantum optics devices by characterizing the entangled two-photon component.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Hongqian Cao, Yanfei Qi, Xibao Gao, Zi Jin Wei, Jiarui Xia, Lei Wang, Hao Wang, Yang Yang, Junbai Li
Summary: The novel peptide nanodrug, consisting of three functional motifs - bis(pyrene), FFVLK and CREKA, is used as a two-photon excited photosensitizer for precise photodynamic therapy (PDT), showing excellent two-photon imaging ability, tumor target effect and high reactive oxygen species productivity to improve treatment precision and efficiency in PDT.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Analytical
Wenhui Song, Baoli Dong, Yaru Lu, Zihong Li, Weiyao Zhang, Weiying Lin
Summary: Superoxide anion has been identified as a key signaling molecule in the physiological and pathological processes of diabetes, leading to the development of a new two-photon fluorescent probe called RDX for monitoring abnormal concentrations of superoxide anion in diabetic conditions. The probe showed high sensitivity, excellent selectivity, and low toxicity, and successfully imaged tissue and diabetic mice, demonstrating its potential for clinical applications.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Nanoscience & Nanotechnology
Sebastian G. Mucha, Marta Piksa, Lucyna Firlej, Agnieszka Krystyniak, Miroslawa O. Rozzycka, Wioletta Kazana, Krzysztof J. Pawlik, Marek Samoc, Katarzyna Matczyszyn
Summary: This study explores acetone-derived polymer dots (PDs) as candidates for albumin probes. The PDs show no cytotoxicity, exhibit high photostability, and demonstrate green fluorescence under both one-photon and two-photon excitation. The results indicate that the PDs are sensitive to the proteinaceous environment and can enhance their fluorescence through dispersion within proteins. Furthermore, the PDs do not disrupt the secondary protein structures and can serve as good nanomarkers for non-destructive probing and sensing of albumins.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Engineering, Environmental
Sweta Rani, Rahul Kumar Das, Arun Jaiswal, Gaurav Pratap Singh, Ajinkya Palwe, Sumit Saxena, Shobha Shukla
Summary: In this study, a 4D ultra-sensitive nanosensor based on multimodal carbon quantum dots was developed using two-photon lithography. The sensor can detect organo-arsenic(V) species at ppb levels and has sub-wavelength resolved features with selective sensitivity towards the analyte. By measuring the change in fluorescence intensity, concentrations of the analyte as low as 1 ppb can be detected.
CHEMICAL ENGINEERING JOURNAL
(2023)