查找使用阿拉丁产品的科研文献

Amperometric detection of chloramine-T based on its reaction with p-aminophenylboronic acid

Hui Pan,Gao Wenyue,Nsabimana Jacques,Li Yunhui,Yang Xiuyun,Gao Ying,Shao Jing,Xu Guobao

The authors describe a method for amperometric determination of chloramine-T that is based on the indirect detection of chloramine-T by detecting p -quinone imine ( p -QI) that is generated by oxidation of p -aminophenylboronic acid by chloramine-T. p -QI can be detected with excellent selectivity and at low potential by using a glassy carbon electrode. Hence, the method displays attractive features such as high sensitivity, wide detection range and excellent selectivity. The electrode has two linear responses in the 50 nM to 100 μM concentration range and a 6 nM detection limit. Compared to other electrochemical methods, this assay has a detection limit that is better by three orders of magnitude. The relative standard deviation is 3.4% for the determination of 10 μM of the medical chloramine-T sample, and the recovery of a samples containing chloramine-T at a level of 10 μM is 115%. Highly sensitive electrochemical detection of chloramine-T is achieved based on the reaction of chloramine-T with p -aminophenylboronic acid with a detection limit of 6 nM.

Vortex-Assisted Liquid–Liquid Microextraction for the Determination of Chloramine-T in Cosmetics Coupled with High-Performance Liquid Chromatography

Juan Wang,Zhihua Li,Yaling Yang

Vortex-assisted liquid–liquid microextraction is reported for the preconcentration of chloramine-T before determination by high-performance liquid chromatography with a diode array detector. Magnetite nanoparticles were used to remove hydrophobic additives in cosmetics by physical adsorption. The method used sonication for 30 min at 45°C in 40% hydrochloric acid to convert the analyte to p-toluenesulfonamide. 1-Hexanol was the extraction solvent with vortex mixing. The extraction conditions were optimized to provide a linear dynamic range from 0.5 to 500.0µg/mL. The recovery of chloramine-T was from 90.8 to 100.9% with a relative standard deviation from 3.7 to 6.5%. The limit of detection was 8.2 mg/kg and the enrichment factor (EF) was 100. Good repeatability, quantitative recovery, and a high EF demonstrated the suitability of the procedure for the determination of chloramine-T in cosmetics.

A new proposed semi-quantitative method for the organic additives analysis in traditional lime mortar

Kuanrong Zhai,Bingjian Zhang,Longguan Zhu

To improve the performance of lime mortar, ancient craftsmen often added various additives to mortars, including inorganic and organic materials. The analysis of mortar additives plays an important role in the conservation and restoration of historical buildings. However, it is quite difficult to accurately identify the species of additives. This paper proposed a series of semi-quantitative analytical procedures to identify the organic additives in ancient lime mortars. By using reagents such as phenolphthalein, periodic acid, acetylacetone, anthrone, bicinchoninic acid (BCA), iodine-potassium iodide, chloramine T, etc., organic additives such as triglyceride, soluble sugar, starch, and protein (including blood, gelatine, and other unknown proteins) remaining in ancient lime mortar were accurately detected, respectively. The linear relationship of the standard curve was significant, and the detection limits for the target additives were below 7 µg/mL. The process is easy to operate within 6 h, and it is suitable for rapid in-situ testing.

Biomimetic Janus Particles Induced In Situ Interfacial Remineralization for Dentin Hypersensitivity

Bing Han,Yilin Song,Shi Wang,Tiantian Yang,Zetao Sun,Aijing Wang,Moran Jin,Zhenzhong Yang,Xiaoyan Wang,Fuxin Liang

Dentin hypersensitivity (DH), caused by the exposure of dentin tubules, is a common complaint of dental patients. Although occlusion of the exposed tubules is the primary treatment approach, the complex oral environment, and multiple simultaneous requirements often hinder its implementation. In this study, strawberry-shaped hemispheric Janus particles (JPs) are synthesized, and their use in the treatment of DH is evaluated in vitro and in an animal model. The hemispheric side of the JPs is modified with polymers of quaternary ammonium salts (QASs) to form a superhydrophobic coating with antibiofilm properties, while the flat side is modified with catechol groups able to form strong bonds with dentin. Even after 1 h of ultrasonication or 1000 rounds of thermal cycling, the dentin tubules are completely occluded by the JPs. Moreover, biofilm formation is not observed, and the area of living bacteria is less than 1% compared to the blank control and sodium fluoride (NaF)-treated groups. In a rat model, the dentin tubules in the fixed specimens are completely occluded at day 3, much earlier than the occlusion obtained with commonly used NaF. These results demonstrate that JPs can provide a novel approach to the treatment of DH.

Functional remineralization of dentin artificial caries lesions via poly-L-aspartic acid‑calcium complexes

Hongli Zhang,Weijia Zhao,Wei Liu,Yuedan Xu,Dongni Shen,Yiru Wang,Yuan Qiu,Yizhou Zhang,Ling Zhu,Zhifang Wu,Baiping Fu,Zihuai Zhou

Dental caries is a common oral disease and lacks an effective recovery method. The objective of the study was to investigate the remineralization efficiency of polyelectrolyte‑calcium complexes pre-precursor (PCCP) and polymer-induced liquid-like precursors (PILP) processes on mechanical and biochemical properties of dentin artificial caries lesions (ACLs) evaluated with micro-CT, SEM, TEM, ATR-FTIR, Raman spectra and nanoindentation. The human dentin ACLs were prepared with the depth of 100–120 μm. The intact dentin served as positive control and the dentin ACLs as negative control. The dentin ACLs were either incubated in poly-L-aspartic acid‑calcium suspension (PAsp-Ca, 4 g/L-5.44 M) followed by phosphate solution (0.325 M), and further incubated in artificial saliva serving as PCCP group, or in PAsp-stabilized amorphous calcium phosphate solution serving as PILP group. The micro-CT and SEM findings with EDX indicated that mineral contents of the dentin ACLs were dramatically increased in PCCP group, but, to some degree in PILP group. TEM and nanoindentation results showed that a heavy remineralization of dentin ACLs was obtained via PCCP process with an obvious recovery of mechanical properties while a poor remineralization via PILP process. In conclusion, the PCCP process is a promising strategy for functional remineralization of dentin caries lesions.

Ultrasensitive electrochemical sensor with renewable ratio signal for real-time monitoring of cyanide in Baijiu

Chen Li,Yuan Liu,Yiqing Guo,Wang Guo,Xinai Zhang,Wen Zhang,Xiaobo Zou,Zongbao Sun

Although electrochemical sensors offer a convenient approach for cyanide detection, they often require multiple components or complex instrumentation. To address this limitation, we designed a covalent organic framework-encapsulated thionine-modified silver‑gold composite (Ag-Au@COF-Thi) sensor that integrates sensitivity and simplicity into a single platform. Ag Au nanoparticles are embedded within a COF matrix, with Thi stably adsorbed on the Au surface to provide an internal reference. The sensor is integrated into a miniaturized electrochemical platform, enabling point-of-care cyanide detection via dual-signal readout: target (I CN − ) and reference (I Thi ). After each cycle, the sensor breaks down the silver-cyanide complex and restores the electrode surface, ensuring repeatable performance. Under optimal conditions, the I CN − / I Thi signal ratio correlates linearly with cyanide concentration from 1 ng/mL to 0.5 μg/mL, achieving a detection limit of 0.82 ng/mL. This sensor effectively quantifies cyanide in Baijiu and fermented grains, offering a promising method for food contamination monitoring.

Quaternary ammonium chitosan film loading ultrasmall calcium phosphate nanoclusters for biomimetic mineralization with antibacterial ability

Xiangtao Liu,Sisi Zhang,Haiyan Zheng,Mengyao Bian,Linna Qian,Weijia Zhao,Ying Shi,Zhifang Wu

Dental caries, primarily induced by plaque biofilm, is a significant challenge in oral health due to the disruption of the equilibrium between mineralization and demineralization processes. The primary objective in caries management is to preserve biofilm homeostasis while promoting the repair and regeneration of dental hard tissues, thereby restoring the structural integrity and functionality of the affected teeth. This study aimed to develop a multifunctional film with mineralizing and antibacterial abilities by incorporating ultrasmall amorphous calcium phosphate (ACP) nanoclusters (~1 nm) into hydroxypropyl trimethyl ammonium chloride chitosan (HACC) matrix. The ACP nanoclusters were synthesized using polyacrylic acid and polyaspartic acid as stabilizers and were homogeneously dispersed into the HACC matrix to form ACP@HACC film. The capacity for Ca and P ions release from ACP@HACC film was evaluated by inductively coupled plasma-mass spectrometry, demonstrating a sustained ion release over a period of 7 days. The ACP@HACC film induced the mineralization of type I collagen fibrils within 4 days. In vivo studies further confirmed the occurrence of dentin remineralization after 4 days. The remineralization process mediated by the ACP@HACC film significantly restored the elastic modulus and microhardness of demineralized dentin. Additionally, cytotoxicity assessments confirmed the excellent biocompatibility of the ACP@HACC film. Dentin treated with the ACP@HACC film demonstrated antibacterial ability against Streptococcus mutans in vitro. The ACP@HACC film integrates the dual functionalities of mineralization and antibacterial activity while maintaining excellent biocompatibility. This innovative approach shows potential for the treatment of early carious lesions, offering a clinically viable supplement to conventional restorative strategies.

Highly stable and bioactive yak type I collagen gels for accelerated healing of photoaging skin

Yi Yang,Bei Tian,Xinyu Tian,Linyan Yao,Jianxi Xiao

Excessive ultraviolet radiation is one of the most common external factors causing skin photoaging, which leads to collagen degradation, wrinkle formation, pigmentation, and is even associated with skin disorders such as seborrheic keratosis and skin tumors. Although various strategies have been developed to treat photoaging skin; however, they suffer from poor stability, risk of allergic reactions, and prolonged recovery periods. In this study, we develop a novel highly stable and bioactive yak type I collagen-based hydrogels dressing to promote the rejuvenation of photoaged skin. The YIC gel demonstrated excellent stability over a six-month period, and maintained the intact triple-helical structure of collagen. It also displayed shear-thinning behavior and notable ductility. In vitro cell experiments confirmed its favorable biocompatibility and bioactivity.Non-invasive Combo evaluations demonstrated the remarkable ability of YIC gel to restore dermal density, elasticity, hydration, and transepidermal water loss to healthy levels, surpassing the efficacy of the commercial product. Histological analysis revealed YIC gel significantly reduced epidermal thickness, promoted the deposition and regeneration of collagen, demonstrating greater efficacy than the commercial product. Antioxidant indicators further highlighted the antioxidant properties of YIC gel, including reduced MDA content, increased SOD activity and GSH content. Immunofluorescence staining suggested that the YIC gel may enhance collagen synthesis through modulation of the TGF-β/Smad signaling pathway. This YIC gel offers valuable insights into its protective effects against skin photoaging and highlights its promising applications in cosmetic formulations.

In situ Synthesis of Amorphous Fluorinated Calcium Phosphate Nanoparticles via a Dual-Component Hydrogel for Biomimetic Tooth Remineralization

Zhixin Zhang,Zhe Wang,Jiangling Su,Qi Yang,Zihan Cui,Xiaoping Tang,Baiping Fu

Objective To report the in situ synthesis of amorphous fluorinated calcium phosphate (AFCP) nanoparticles within a dual-component hydrogel and evaluate their efficacy for enamel remineralization and dentinal tubules (DTs) occlusion.Materials and Methods The AFCP hydrogel was constructed using hydroxypropyl methylcellulose (HPMC) and carboxymethyl chitosan (CMC) to stabilize calcium, phosphate, and fluoride ions in a metastable amorphous state. Physicochemical characterization was performed by FTIR, XRD, TEM, and SEM-EDX. Biocompatibility was assessed via CCK-8 assays and oral mucosal irritation test. Demineralized enamel and dentin specimens (n=8) were treated with deionized water, fluoride (NaF, 2000 ppm F), 10% CPP-ACP with 900 ppm F (GC Tooth Mousse Plus, Japan), or AFCP hydrogel, and immersed in artificial saliva for 7 days. Remineralization was evaluated by SEM, XRD, and nanoindentation, followed by in vivo validation in a rabbit model.Results The hydrogel generated AFCP nanoparticles (30–80 nm) that remained amorphous in artificial saliva for over 2 hours before crystallizing into hydroxyapatite. The hydrogel exhibited negligible cytotoxicity and no oral mucosal irritation. After 7 days, the AFCP hydrogel induced dense mineral deposition that completely occluded exposed DTs and formed a ~32 µm remineralized layer on acid-etched enamel, substantially outperforming fluoride and CPP-ACP + NaF. XRD confirmed the newly formed mineral as hydroxyapatite-like. Treatment with the AFCP hydrogel restored the mechanical properties of enamel and dentin to near-physiological levels, achieving the greatest recovery among the four groups (P < 0.05). In vivo results further validated its remineralization and tubule-occluding efficacy.Conclusion The AFCP hydrogel functions as an exogenous mineral reservoir, enabling sustained ion release or direct transformation into hydroxyapatite for in situ enamel remineralization and DTs occlusion. This non-invasive strategy offers a promising therapeutic approach for early caries and dentin hypersensitivity.

A Hydroxypropyl Methylcellulose Film Loaded with AFCP Nanoparticles for Inhibiting Formation of Enamel White Spot Lesions

Zhixin Zhang,Ying Shi,Haiyan Zheng,Zihuai Zhou,Zhifang Wu,Dongni Shen,Yiru Wang,Yizhou Zhang,Zhe Wang,Baiping Fu

Electrospun flexible magnesium-doped silica bioactive glass nanofiber membranes with anti-inflammatory and pro-angiogenic effects for infected wounds

Mingyue Liu,Xiangsheng Wang,Jie Cui,Hongsheng Wang,Binbin Sun,Jufang Zhang,Bernd Rolauffs,Muhammad Shafiq,Xiumei Mo,Zhanyong Zhu,Jinglei Wu

Antibacterial, anti-inflammatory, and pro-angiogenic properties are prerequisites for dressing materials that accelerate the healing process of infected wounds. Herein, we report a magnesium-doped silica bioactive glass (SiO2/MgO) nanofiber membrane prepared by electrospinning. Our results demonstrate that this SiO2/MgO nanofiber membrane has good flexibility and hydrophilicity, which give it intimate contact with wound beds. In vitro assessments illustrate its good cytocompatibility and bioactivity that contribute to its robust cell proliferation and angiogenesis. It shows capacity in modulating the cellular inflammatory response of murine macrophages. In addition, in vitro assays prove its good antibacterial activity against both Gram-positive and Gram-negative strains. In a full-thickness skin defect inoculated with Staphylococcus aureus in mice, it effectively inhibits bacterial infection. Both gene expression and histological/immunohistochemical analyses confirmed the down-regulated pro-inflammatory factors, up-regulated anti-inflammatory factors, and enhanced angiogenesis. Taken together, these desirable properties work in concert to contribute to the rapid healing of infected wounds and make it a good candidate for wound dressing materials.

Cyclic freeze–thaw grinding to decellularize meniscus for fabricating porous, elastic scaffolds

Yangfan Ding,Weixing Zhang,Binbin Sun,Xiumei Mo,Jinglei Wu

Decellularized meniscus extracellular matrix (dmECM)-based biological scaffolds in the forms of sponge, hydrogel, nanofiber, and composite have gained increasing interest in meniscus tissue engineering and regeneration. A common shortcoming of those scaffolds is insufficient mechanical strength and poor elasticity. Herein, we report a practicable protocol for milder meniscus decellularization to prepare elastic, porous dmECM scaffolds. Porcine meniscus was pulverized by cyclic freeze–thaw grinding and then treated with DNase to obtain fine dmECM particles. Individual dmECM particles were condensed to bulk preparation by centrifuge, followed by lyophilization to form blocks, and finally crosslinked by dehydrothermal treatment to obtain porous dmECM scaffolds. Our results show that the freeze–thaw grinding method was effective in removing cellular DNA with good retention of meniscus-derived bioactive components. The dmECM scaffold had porous structure with interconnected mesopores and good mechanical properties. Primary articular chondrocytes proliferated robustly and maintained chondrogenic characteristics and produce abundant collagen on dmECM scaffolds. Evaluation of biocompatibility in a rat model shows that the dmECM scaffold elicited minor foreign body reactions, indicating effective antigen removal from dmECM. This study provides an alternative for preparing dmECM and fabricating porous scaffolds for meniscus repair and regeneration.