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Comprehensive Summary: Fluorophores play a significant role in achieving high‐contrast imaging in complex physiological environment. Herein, we present the results of our studies on the development of various fluorophores, such as anti‐solvatochromic fluorophores, long wavelength emission two‐photon fluorophores, large Stokes shift fluorophores and solid‐state fluorophores, to achieve high‐contrast bioimaging in physiological environments. In this study, we have primarily focused on the design, optical performance, imaging mechanisms, and the applications of these fluorophores with respect to complex physiological conditions. What is the most favorite and original chemistry developed in your research group? Orderly assembly of small‐molecule dyes and their applications for long‐term in situ bioimaging. How do you get into this specific field? Could you please share some experiences with our readers? We have long been engaged in the field of fluorescence imaging for biomedical applications, and realized that obtaining the target's in situ information is urgent and challenging. Our exploration revealed that the orderly assembly of specific molecular dyes is an effective strategy to overcome this problem. Keeping curiosity and thinking is the key to solving problems in scientific research. What is the most important personality for scientific research? Clear mind and perseverance. What's your hobby? Communicating with Youngs. How do you keep balance between research and family? To make a proper allotment of time. How do you supervise your students? Let them know what they want and fight for it. [ABSTRACT FROM AUTHOR]

Fluorescent probes have become an indispensable tool in the detection and imaging of biological and disease‐related analytes due to their sensitivity and technical simplicity. In particular, fluorescent probes with far‐red to near‐infrared (FR‐NIR) emissions are very attractive for biomedical applications. However, many available FR‐NIR fluorophores suffer from small Stokes shifts and sometimes low quantum yields, resulting in self‐quenching and low contrast. In this work, we describe the rational design and engineering of FR‐NIR 2,4,6‐triphenylpyrylium‐based fluorophores (TPP‐Fluors) with the help of theoretical calculations. Our strategy is based on the appending of electron‐donating substituents and fusing groups onto 2,4,6‐triphenylpyrylium. In contrast to the parent TPP with short emission wavelength, weak quantum yields, and low chemical stability, the obtained novel TPP‐Fluors display some favorable properties, such as long‐wavelength emission, large Stokes shifts, moderate to high quantum yields, and chemical stability. TPP‐Fluors demonstrate their biological value as mitochondria‐specific labeling reagents due to their inherently positive nature. In addition, TPP‐Fluors can also be applied to develop ratiometric fluorescent probes, as the electron‐donating ability of the 2,6‐phenyl substituents is closely correlated with their emission wavelength. A proof‐of‐concept ratiometric probe has been developed by derivatizing the amino groups of TPP‐Fluor for the detection and imaging of nitroreductase in vitro and in hypoxic cells. [ABSTRACT FROM AUTHOR]

Superoxide anion radical (O 2 − ), the “primary” reactive oxygen species (ROS) in living systems, is linked to a variety of physiological and pathological processes. Therefore, developing an effective strategy to monitor the fluctuation of O 2 − in biological systems is of great importance. This paper describes a new turn-on two-photon fluorescent probe for endogenous O 2 − detection and imaging, which was rationally designed and synthesized via a non-redox strategy. In the presence of O 2 − , the probe exhibited notable fluorescence enhancement (∼235-fold) with a low detection limit down to 1 nM, indicating a high signal-to-background ratio and excellent sensitivity. In addition, short response time, good biocompatibility, low cytotoxicity, long-term stability against light illumination, specificity to O 2 − over general reductants, and pH stability were demonstrated, indicating that the requirements for cellular O 2 − determination are met. Furthermore, the probe was successfully applied in two-photon fluorescence imaging of endogenous O 2 − in living cells and tissues and showed high imaging resolution and a deep-tissue imaging depth of ∼150 μm, illustrating the promising potential for practical applications in complex biosystems and providing a valuable theoretical basis and technical support for the study of physiological and pathological functions of O 2 − . [ABSTRACT FROM AUTHOR]