Y-Shaped D-A Type Thioxanthone Derivatives: Mechano-Induced Thermally Activated Delayed Fluorescence and High-Contrast Mechano-Responsive Luminescence.

High-contrast mechano-responsive luminescence (MRL) materials with mechano-induced emission enhancement properties are fascinating candidates but few, for applications in rewritable media and recording devices. Here, an interesting design strategy of "Y-shape" donor-acceptor (D-A) type molecules for high-contrast MRL materials was presented, based on substituted diphenylamine donor and planar acceptor. Interestingly, their D-A torsion angles are small in crystals but increased after ground, resulted in planar and twist intramolecular charge transfer (PICT and TICT) states, respectively. Therefore, high-contrast MRL switching between weak blue (450 nm) fluorescence and bright yellow (552 nm) thermally activated delayed fluorescence (TADF) can be achieved for compound TXDO (4,4'-dimethoxydiphenylamine donor), which photoluminescence quantum yield increased from 2.8 % to 54.7 % after ground. Most importantly, the two independent D-A conjugation dihedral angles are actually independent in the "Y-shape" molecules. Especially for compound TXDT (4,4'-di-tert-butyldiphenylamine donor), its crystal exhibited both PICT and TICT processes inside, resulted from the different dihedral angles of 11.8° and 35.5°, respectively. The TXDT crystal thus showed dual-peak emission, including both TICT fluorescence and PICT room-temperature phosphorescence. Therefore, this strategy of "Y-shape" D-A type molecules provide a new approach to design advanced luminescent materials with mechano-induced TADF feature, for high-contrast MRL and single-component white luminescence.

Photoinduced Radical Persistent Luminescence in Semialiphatic Polyimide System with Temperature and Humidity Resistance.

Organic persistent luminescence (pL) systems with photoresponsive dynamic features have valuable applications in the fields of data encryption, anticounterfeiting, and bioimaging. Photoinduced radical luminescent materials have a unique luminous mechanism with the potential to achieve dynamic pL. It is extremely challenging to obtain radical pL under ambient conditions; on account of it, it is unstable in air. Herein, a new semialiphatic polyimide-based polymer (A0) is developed, which can achieve dynamic pL through reversible conversion of radical under photoexcitation. A "joint-donor-spacer-acceptor" molecular design strategy is applied to effectively modulate the intramolecular charge-transfer and charge-transfer complex interactions, resulting in effective protection of the radical generated under photoirradiation. Meanwhile, polyimide-based polymers of A1-A4 are obtained by doping different amine-containing fluorescent dyes to modulate the dynamic afterglow color from green to red via the triplet to singlet Förster resonance energy-transfer pathway. Notably, benefiting from the structural characteristics of the polyimide-based polymer, A0-A4 have excellent processability, thermal stability, and mechanical properties and can be applied directly in extreme environments such as high temperatures and humidity.

Boosting the Phosphorescence Efficiency in Doped Organic Crystals: Critical Role of Hydrogen Bonding.

Host-guest doping systems with phthalimides (BI) and N-methylphthalimide (NMeBI) as the host and 1,8-naphthalimide (NI) and 4-bromo-1,8-naphthalimide (4BrNI) as the guest have been developed. The 0.2% NI/BI (molar ratio) with a strong C=O···H-N hydrogen bond exhibited a phosphorescence quantum efficiency (29.2%) higher than that of NI/NMeBI with a weak C=O···H-C hydrogen bond (10.1%). A similar trend was observed in the 4BrNI guest system. A remarkable phosphorescent efficiency of 42.1% was achieved in a 0.5% 4BrNI/BI composite, which represents the highest value in NI-based phosphors. This research indicates stronger hydrogen bonding may have a greater contribution in boosting the phosphorescence efficiency.

Construction of photo-induced zinc-doped carbon dots based on drug-resistant bactericides and their application for local treatment.

In this project, we propose a highly effective photosensitizer that breaks through drug-resistant bacterial infections with zinc-doped carbon dots. By passing through the membrane of drug-resistant bacteria, the photosensitizers produce ROS in bacteria under the action of blue light to directly kill bacteria, so as to realize the antibacterial local treatment of drug-resistant bacteria. The experiment firstly uses an efficient one-step hydrothermal method to prepare zinc-doped red-light CDs as photosensitizers, in which zinc metal was doped to improve the optical properties of the CDs. Then we try first to use EDTA as a second-step attenuator for preparing CDs to obtain photosensitizers with high-efficiency and low toxicity. In vitro cytotoxicity tests, bacterial effect tests, and in vivo animal experiments have also demonstrated that this antibacterial method has great potential for clinical translation, with a bactericidal efficiency of up to 90%. More notably, we used this antibacterial regimen seven times repeatedly to simulate the bacterial resistance process, with a bactericidal efficiency of up to 90% every time. The result indicated that S. aureus did not develop resistance to our method, showing that our method has the potential to break through drug-resistant bacterial infections as an alternative to antibiotic candidates.

Effect of Vaginoscopy versus Conventional Hysteroscopy on Pain, Complications, and Patient Satisfaction in Patients with Endometrial Polyps.

Background: Hysteroscopy is considered the gold standard for diagnosing intrauterine pathology. Traditional hysteroscopy requires the placement of a vaginal speculum and cervical forceps, which are large in diameter, causing discomfort and pain to the patient and even causing vagal reflexes. Aims: To investigate the impact and clinical value of vaginoscopy versus conventional hysteroscopy on pain, complications, and patient satisfaction in patients with endometrial polyps and to analyse the advantages of clinical application of vaginoscopy examination. Materials and Methods: One hundred and twenty-five patients with endometrial polyps treated in our hospital from May 2021 to December 2021 were selected for this study and divided into 52 cases in the hysteroscopy group and 73 cases in the vaginoscopy group according to the random remainder grouping method. Conventional hysteroscopy was used, and in the vaginoscopy group, vaginoscopy was performed. The impact of pain, complications, patient satisfaction, and clinical value of the two groups was observed and compared. Results: The time taken for the examination varied between the different hysteroscopic methods, with the hysteroscopy group taking the longest time compared to the vaginoscopy group (P < 0.01). The VAS scores immediately after the examination and 30 minutes after the examination were both significantly higher in the hysteroscopy group than in the vaginoscopy group (P < 0.01). The difference in NPY, PGE2, and 5-HT after the pain-causing mediator intervention was significantly better in the vaginoscopy group than in the hysteroscopy group. The difference in the incidence of complications such as abortion syndrome, cervical laceration, uterine perforation, and haemorrhage after treatment was significantly lower in the vaginoscopy group than in the hysteroscopy group. In the vaginoscopy group, the satisfaction rate was 91% significantly higher than that of the hysteroscopy group (P < 0.05). Conclusion: The vaginoscopy technique shortens the examination and treatment time, reduces patient pain, improves patient compliance, reduces the use of preintervention drugs and anaesthetics, and reduces complications.

In vivo study of a novel, safe, rapid, and targeted red carbon dot probe for recognition of tumors with high expression of folate enzyme.

Carbon dots (CDS) have been proved to be a type of ideal biological imaging probe. They have the advantages of spontaneous fluorescence, anti-photobleaching, good biocompatibility and easy surface decoration, and are receiving special attention from researchers. The early imaging diagnosis of tumors has always been a practical means of clinical diagnosis. Finding an efficient and low-toxicity tumor probe is the continuous goal of tumor clinical diagnosis and treatment. Therefore, this article uses the modifiable properties of the surface structure of carbon dots, and at the same time, uses the characteristics of tumors with high expression of folate receptors (FR) that can specifically take up folic acid (FA) to construct folic acid carbon dot conjugates (FA-CDs) to achieve targeted tumor uptake. Firstly, CCK8 toxicity tests proved that FA-DCCDs had good biocompatibility and were almost non-toxic. Further, confocal cell imaging experiments, microplate quantitative experiments and flow cytometry experiments proved that FA-CDs were selective and more easily absorbed by tumor cells with high expression of folate receptors, and bare carbon dots could be absorbed into cells without selectivity. Through in vivo experiments, the law of injection of bare CDs into the body was explored, which proved that they had no obvious accumulation and had high distribution in the liver and kidneys. FA-CDs was applied to the targeted imaging of a mouse tumor model in vivo for the first time, which proved again that the carbon point coupled with folic acid had selectivity for tumor cells with high expression of FR receptors, which provided a basis for tumor drug research and early clinical diagnosis of tumors.

Method development and validation for the high-performance liquid chromatography assay of gastrodin in water extracts from different sources of Gastrodia elata Blume.

Gastrodia elata Blume is commonly used as a medical herb in China for ameliorating headaches, dizziness, and convulsions. In previous studies, water extracts of G. elata Bl. (WGE) have demonstrated potential to act as therapeutic agents to improve depression-like symptoms in rats. As gastrodin (GAS) is a major active compound in WGE, its quantitation in WGE is important for quality control. The objective of this study was to develop an optimized and validated reversed-phase high-performance liquid chromatography method for the analysis of GAS in different sources of WGE. We evaluated the GAS content in varieties of G. elata Bl. including G. elata Bl. f. glauca S. Chow and G. elata Bl. f. elata. We also evaluated the GAS content of the latter variety from two different origins, Yun-nan and Hu-nan. The results indicate that the amount of GAS analyzed in WGE from G. elata Bl. f. glauca S. Chow is five times higher than that of G. elata Bl. f. elata from Yun-nan and Hu-nan. A significant difference in GAS content was observed between varieties of G. elata Bl., although not between locations of origin.

[Separation and identification of chlorogenic acid and related impurities by high performance liquid chromatography-tandem mass spectrometry].

A method using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established for analysis and identification of chlorogenic acid along with its related impurities. A Gemini C18 HPLC column (4.6 mm x 150 mm,5 microm) was used with acetonitrile-water ( containing 0.1% formic acid) (8:92, v/v) as mobile phase. Eight related impurities of chlorogenic acid were identified and their structures were determined by using online HPLC-MS/MS and photodiode array detector (DAD). The method is quick, simple and can be used directly to identify the structure of unknown trace substances in the sample of chlorogenic acid.