Organic molecules with an aggregation-induced emission (AIE) effect have recently been attracting more and more attention due to their colossal potential in solid emitters and chemo/biosensors. The number and variety of AIEgen compounds are expanding very rapidly to obtain better application performance and a wider area of application. Among AIEgen systems, tetraphenylethylene (TPE) and its derivatives are the class that have received the most extensive study and the most rapid development because of their facile synthesis. Due to its C2 symmetry and at least tetratopic reaction positions, the TPE unit is also an ideal building block for constructing macrocycles and cages. The resultant cyclic TPE compounds have exhibited many exceptional performances that are difficult to access in their open chain counterparts, such as AIE enhancement, improvement in selectivity and sensitivity as sensors, emission tuning by guests, supramolecular catalysis, further disclosure of the AIE mechanism, molecular adsorption, storage and release, the propeller-like conformation exploitation of the TPE unit in chiral materials and so on. Recently, therefore, a large variety of studies about the synthesis, properties and application research of TPE macrocycles and cages have been reported. These TPE macrocycles and cages significantly expand the research area for the AIE phenomenon and its applications, and represent a development of the AIE area. However, up to now, no review of TPE macrocycles and cages has been available. Thus, this review serves as a summary of the designs, synthesis, photophysical properties, self-assembly, applications and prospects of TPE macrocycles and cages.

Various strategies for TSQ-induced fluorophore stabilization and their application in sm-FRET as well as in super-resolution imaging microscopy are thoroughly reviewed.

Early diagnosis of malignant skin lesions is critical for prompt treatment and a clinical prognosis of skin cancers. However, it is difficult to precisely evaluate the development stage of nonmelanoma skin cancers because they are derived from the same tissues as a result of the uncontrolled growth of abnormal squamous keratinocytes in the epidermis layer of the skin. In the present study, we developed a linear-kernel support vector machine (LSVM) model to distinguish basal cell carcinoma (BCC) from actinic keratosis (AK) and Bowen’s disease (BD). The input parameters of the LSVM model consist of appropriate lifetime components and entropy values, which were extracted from two-photon fluorescence lifetime imaging of hematoxylin and eosin (H&E)-stained biopsy sections. Different features used as inputs for SVM training were compared and evaluated. In constructing the SVM models, features obtained from the lifetime (τ2) of the second component were found to be significantly more predictive than the average fluorescence lifetime (τm) in terms of diagnostic accuracy, sensitivity, and specificity. The above findings were confirmed on the basis of the receiver operating characteristic (ROC) curves of diagnostic models. Shannon entropy was added to the SVM models as an independent feature to further improve the diagnostic accuracy. Therefore, fluorescence lifetime analysis and entropy calculations can provide highly informative features for the accurate detection of skin neoplasm disorders. In summary, fluorescence lifetime imaging microscopy (FLIM) combined with the SVM classification exhibited great potential for developing an effective computer-aided diagnostic criterion and accurate cancer detection in dermatology.

Single molecule localization microscopy as an advanced optical imaging technique is capable of super-resolution imaging of biological targets with the size below the optical diffraction limit. It is promising to provide powerful tools for the exploration of occurrence mechanism of severe diseases and precisely therapeutic method at single cell/organelle level, which exhibits wide applications in biomedical field. Generally, stochastic optical reconstruction microscopy (STORM) is prominently dependent on large amount of imaging buffers (Redox enzymes) and thiol-containing reagents for the ideal photoblinking behaviors of optical probes. However, the imaging buffer and thiol-containing reagents are harmful for the live cells, which make it difficult to carry out STORM imaging in live cells. Therefore, it is of significance to exploit new approaches to display STORM imaging in live cells. In this work, we provided a new strategy to facilitate the design of live cell STORM imaging probes with improved photo-blinking mechanism. A new fluorescent pentamethine cyanine probe with a thiol-attachment (SHCH 2 CH 2 CH 2-) at the N-position of one indoline moiety was synthesized to show spontaneously photoblinking behavior caused by intramolecular ring-closing/-opening processes. The fluorescent probe is biologically compatible with rare cytotoxicity and suitable for the live cell imaging. The probe can exhibit excellent photo-blinking under the direct illumination of a single laser beam (656 nm) with low power density (200 W•cm-2 for solution sample and 100 W•cm-2 for cell sample, respectively), without using any imaging buffer or thiol-chemicals. And the fluorescent probe was used to test cell toxicity with CCK-8, showed almost no cytotoxicity after 24 h incubation. The photo-blinking frames were collected