A fluorescent probe for specific dual recognition of Ni2+ and pH.

Nickel ion (Ni2+) and pH play an important role in environment and living organisms. A fluorescent probe "naphthalimide- s-triazine" (NCNS) for targeted dual detection of Ni2+ and pH was synthesized. As a result, NCNS exhibits excellent optical properties: a much larger Stokes shift (140 nm), eminent changes of fluorescence intensity and significant red-shift both for Ni2+ and pH. As for the detection of Ni2+, the selectivity is high and the anti-interference is strong. NCNS can fluorescently detect Ni2+ in a wider pH range from 4.0 to 10.5. It provides a much lower limit of detection (LOD, 20.03 nM), a rapid response time (150 s) and six times reversibility, showing the high sensitivity. Particularly, NCNS can be applied to fluorescently detect Ni2+ in actual water samples and HA-VSMC imaging. In the detection of pH, the probe generates a ratiometric fluorescence in a wide pH range (3.0 âˆ¼ 12.3). NCNS has been successfully made test paper both for Ni2+ and pH. The mechanisms of the double recognition are verified by the density functional theory (DFT) calculations and the nuclear magnetic resonance (NMR) titration experiments.

A Fluorescent Probe for Hg2+ Specific Recognition Based on Xanthene and its Application in Food Detection and Cell Imaging.

The mercury-loving unit aminothiourea was introduced into the xanthene fluorophore to synthesized the probe molecule NXH. NXH has a specific response to Hg2+, and with the addition of (0 ~ 50 µM) Hg2+, the fluorescence intensity of the probe solution was quenched from 2352 a.u. to about 308 a.u. NXH exhibited excellent detection performance of high sensitivity (LOD = 96.3 nM), real-time response (105 s), wide pH range (2.1 ~ 9.3), and strong anti-interference ability for Hg2+. At the same time, NXH has wide range of applications for Hg2+ detection, which can fluorescence imaging of Hg2+ in Hela cells and tea samples, and can also be made into Hg2+ detection test paper.

A Dual Functional Fluorescent Probe Based on Phenothiazine for Detecting Hg2+ and ClO- and its Applications.

For the efficient detection of Hg2+ and ClO-, a double-analyte-responsive fluorescent probe PTB was successfully synthesized by combining N-butyl-3-formyl phenothiazine with hydrazine benzothiazole, and designing a specific reaction site for recognizing two analytes (Hg2+ and ClO-) in a compound. It was shown that probe PTB successfully formed a stable complex with Hg2+ in the coordination ratio of 2:1 by using the strong sulfur affinity of Hg2+, which resulted in a remarkable "turn-off" effect, with a quenching efficiency of 92.5% and four reversible cycles of Hg2+ fluorescence detection. For the fluorescence detection of Hg2+, the response time is fast (≤ 2 min) and the detection limit is low (7.8 nM), showing extremely high sensitivity, and the performance is obviously better than that of the reported fluorescent probes for detecting Hg2+. In particular, probe PTB has low toxicity and good biocompatibility, and has been successfully used for imaging of Hg2+ in living cells. Moreover, probe PTB uses thioether bond and carbon-nitrogen double bond as reaction sites to detect ClO-, which has large Stokes Shift (149 nm), good selectivity, high quenching efficiency (96.5%) and fast time response (about 10 s), and successfully detects ClO- in actual water samples. The dual functional fluorescent probe PTB is sensitive for Hg2+ and ClO-. It has been successfully used for making pH fluorescent test paper and imaging detection of exogenous Hg2+ in VSMC cells with low toxicity.

Two novel fluorescent probes based on quinolinone for continuous recognition of Al3+ and ClO.

On the basis of classical Schiff base reaction, two novel and efficient fluorescent probes (DQNS, DQNS1) were designed and synthesized by introducing Schiff base structure into dis-quinolinone unit for structural modification, which can be used to detect Al3+ and ClO-. Because the power supply capacity of H is weaker than that of methoxy, DQNS shows better optical performance: a large Stokes Shift (132 nm), identify Al3+ and ClO- with high sensitivity and selectivity, low detection limit (29.8 nM and 25 nM) and fast response time (10 min and 10 s). Through the working curve and NMR titration experiment, the recognition mechanism of Al3+ and ClO- (PET and ICT) probes are confirmed. Meanwhile, it is speculated that the probe has continuity for the detection of Al3+ and ClO-. Furthermore, DQNS detection of Al3+ and ClO- was applied to real water samples and living cell imaging.

A fluorescent probe based on phenothiazine for detection of ClO- with naked-eye color change properties.

Hypochlorite (ClO-) plays a key role in life systems and it is necessary to develop an effective detection method. In view of the significant advantages of the fluorescent probe, we have synthesized a naked-eye recognition fluorescent probe NNCF for the detection of ClO- based on phenothiazine and naphthalimide. The probe NNCF is sensitive (LOD = 9.5 nM) and fast for ClO- (within 30 s), and its Stokes shift is as large as 161 nm. In addition, the probe NNCF has been successfully used for imaging detection of exogenous ClO- in MCF-7 cells with low toxicity.

Development and validation of a preoperative nomogram for predicting the surgical difficulty of laparoscopic colectomy for right colon cancer: a retrospective analysis.

BACKGROUND: In laparoscopic right hemicolectomy for right colon cancer, complete mesocolic excision is a standard procedure that involves extended lymphadenectomy and blood vessel ligation. This study aimed to establish a nomogram to facilitate evaluation of the surgical difficulty of laparoscopic right hemicolectomy based on preoperative parameters. MATERIALS AND METHODS: The preoperative clinical and computed tomography-related parameters, operative details, and postoperative outcomes were analyzed. The difficulty of laparoscopic colectomy was defined using the scoring grade reported by Escal et al . with modifications. Multivariable logistic analysis was performed to identify parameters that increased the surgical difficulty. A preoperative nomogram to predict the surgical difficulty was established and validated. RESULTS: A total of 418 consecutive patients with right colon cancer who underwent laparoscopic radical resection at a single tertiary medical center between January 2016 and May 2022 were retrospectively enrolled. The patients were randomly assigned to a training data set ( n =300, 71.8%) and an internal validation data set ( n =118, 28.2%). Meanwhile, an external validation data set with 150 consecutive eligible patients from another tertiary medical center was collected. In the training data set, 222 patients (74.0%) comprised the non-difficulty group and 78 (26.0%) comprised the difficulty group. Multivariable analysis demonstrated that adipose thickness at the ileocolic vessel drainage area, adipose area at the ileocolic vessel drainage area, adipose density at the ileocolic vessel drainage area, presence of the right colonic artery, presence of type III Henle's trunk, intra-abdominal adipose area, plasma triglyceride concentration, and tumor diameter at least 5 cm were independent risk factors for surgical difficulty; these factors were included in the nomogram. The nomogram incorporating seven independent predictors showed a high C-index of 0.922 and considerable reliability, accuracy, and net clinical benefit. CONCLUSIONS: The study established and validated a reliable nomogram for predicting the surgical difficulty of laparoscopic colectomy for right colon cancer. The nomogram may assist surgeons in preoperatively evaluating risk and selecting appropriate patients.

[Synthesis of magnetic graphene oxide modified with dodecylamine and its application for the determination of seven endocrine-disrupting chemicals in environmental water samples].

Magnetic graphene oxide (MGO) modified with dodecylamine (DDA) was synthesized in this work. The as-prepared MGO-DDA was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometer measurements. The material was used as the absorbent in magnetic solid-phase extraction (MSPE) for seven environmental endocrine-disrupting chemicals (EDCs):estrone (E1), ß-estradiol (E2), estriol (E3), 17α-ethynylestradiol (EE2), hexoestrol (HEX), androstendione (AND), and bisphenol A (BPA). MSPE combined with HPLC-UV was developed for the determination of EDCs in environmental water samples. The effects of the amount of adsorbent, adsorbing time, and the type and volume of eluents on the recoveries of the EDCs were investigated. Under the optimal conditions, good linear relationships between the UV signals and the EDC concentrations were obtained, with R2 greater than 0.999. The limits of detection for all the EDCs were between 0.10 and 0.23 nmol/L. The MSPE-HPLC-UV method was successfully applied to the analysis of the seven EDCs in environmental water samples such as lake water and sewage water samples. The recoveries of all the EDCs in spiked lake water and sewage water samples were between 73.9% and 114.7%, and the RSDs ranged from 0.7% to 11.8%. Thus, the proposed MSPE-HPLC-UV method is simple, reliable, sensitive, and low-cost.