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Trichloroacetic acid is a common nonvolatile byproduct of drinking water disinfection and poses carcinogenic risks to the human body. In this study, four types of nano-oxide@microcrystalline-cellulose-based adsorbents (P25@microcrystalline cellulose, SiO₂@microcrystalline cellulose (MCC-g-GMA@SiO2), Fe3O4@microcrystalline cellulose, and Fe2O3@microcrystalline cellulose) were successfully prepared by the pre-radiation grafting-embedding method. Subsequently, their ability to remove trichloroacetic acid from drinking water was investigated. The micro zonation morphology and surface properties of the materials were characterized and tested using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), Thermogravimetric (TG) analysis, and Scanning electron microscopy (SEM) characterization methods. The effects of monomer concentration, embedding concentration, and absorbed dose on the weight gain rate were systematically investigated. A complete static adsorption equilibrium curve was obtained on the basis of the results of adsorption experiments of four buried nano-oxides. The performance of SiO2@microcrystalline cellulose was found to be significantly higher than that of the other three adsorbents. When the volum percentage of monomer concentration was 30%, the mass percentage of embedding concentration was 4%, and the absorbed dose was 60 kGy, the removal rate of trichloroacetic acid in drinking water reached 83.27%. This series of adsorbent materials present significant potential for practical application in drinking water purification.

Fingerprints are an important trace material evidence for police to identify criminal. Cadmium sulfide quantum dots (CdS QDs) are fluorescent-labeled nanomaterials that can be used to improve the clarity and resolution of fingerprints. In this study, thioglycollic acid (TGA) was successfully modified to CdS QDs using the in-situ radiation reduction method, and synthetic TGA-CdS QDs were combined with polyvinyl acetate (PVAc) to form a TGA-CdS QDs/PVAc gel fingerprint film for fingerprint development. The structure and properties of the TGA-CdS QDs were characterized and tested using Fourier transform infrared (FTIR) spectroscopy, fluorescence spectrum, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The effects of temperature, concentration of TGA-CdS QDs, pH, and mass fraction of the PVAc gel fingerprint film on fingerprint development were investigated. The results showed that a combination of 6 mg/mL TGA-CdS QDs solution with 20% PVAc gel fingerprint film at room temperature (25 ℃) and pH of 9.0 resulted in the clearest, most complete, and high-resolution fingerprint patterns of fluorescence display. The carboxylic acid group formed by TGA-CdS QDs in an alkaline solution completely combined with the amino acids, proteins, fats, urea, and other components of the fingerprint residue attached to the PVAc gel film. Under ultraviolet irradiation, the fingerprint lines were clearly displayed in the form of fluorescence. The fingerprint display method can be effectively used in criminal investigation.

Chlorite and other disinfection byproducts have been listed as carcinogens by the International Center for Research on Cancer. The effective treatment of chlorite is imperative for the drinking water purification process. A series of Non-woven fabric - ethyl methacrylate trimethyl ammonium chloride - nano aluminum oxide (NWF-g-DMC@Al2O3) adsorbent materials were synthesized using the pre-radiation grafting–embedding reaction. In this study, water was used as the solvent to systematically discuss the effects of adsorption dose, monomer concentration, and other factors on the weight gain rate and subsequently evaluate the effects of different weight gain rates, embedding rates, and solution pH on the adsorption rate to obtain a complete static adsorption equilibrium curve. Infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and X-ray diffraction analysis were used to characterize the structure and adsorption properties of the synthesized samples. The results showed that the weight gain rate was the highest at a monomer concentration of 40 %. The adsorption rate was the highest at an adsorption dose of 100 kGy, embedding embedding amount 4 %, pH of 2, and initial concentration of 10 mg/L. The chlorite removal rate of the NWF-g-DMC@Al2O3 adsorbent was 89%. The new adsorbent is expected to be extensively used in the purification of drinking and industrial water.

The integration of two-dimensional Ti3C2Tx nanosheets and other materials offers broader application options in the antibacterial field. Ti3C2Tx-based composites demonstrate synergistic physical, chemical, and photodynamic antibacterial activity. In this review, we aim to explore the potential of Ti3C2Tx-based composites in the fabrication of an antibiotic-free antibacterial agent with a focus on their systematic classification, manufacturing technology, and application potential. We investigate various components of Ti3C2Tx-based composites, such as metals, metal oxides, metal sulfides, organic frameworks, photosensitizers, etc. We also summarize the fabrication techniques used for preparing Ti3C2Tx-based composites, including solution mixing, chemical synthesis, layer-by-layer self-assembly, electrostatic assembly, and three-dimensional (3D) printing. The most recent developments in antibacterial application are also thoroughly discussed, with special attention to the medical, water treatment, food preservation, flexible textile, and industrial sectors. Ultimately, the future directions and opportunities are delineated, underscoring the focus of further research, such as elucidating microscopic mechanisms, achieving a balance between biocompatibility and antibacterial efficiency, and investigating effective, eco-friendly synthesis techniques combined with intelligent technology. A survey of the literature provides a comprehensive overview of the state-of-the-art developments in Ti3C2Tx-based composites and their potential applications in various fields. This comprehensive review covers the variety, preparation methods, and applications of Ti3C2Tx-based composites, drawing upon a total of 171 English-language references. Notably, 155 of these references are from the past five years, indicating significant recent progress and interest in this research area. [ABSTRACT FROM AUTHOR]

Objective To observe the effect of green tea extractive epigallocatechin-3-gallate (EGCG) on degradation of collagen in dental erosion. Methods Sixty-four volunteers with dental erosion were randomly divided into two groups. The custom fitted trays were made from the heat curable braces and were injected with carboxymethyl cellulose sothum (CMC) hydrogel in one group (control group) or CMC hydrogel with EGCG added in another (experimental group). These trays were used during sleep and removed from oral cavity in the next morning. The content of carboxy-termina] telopeptide of type I collagen (ICTP) were determined by radioimmunoassay kit at 1 d before the experiment, and 1, 2, 3, 4 weeks after the experiment. Results Both the types and time showed significant effects on ICTP. The incubation in EGCG resulted in relatively rapid and significant (P<0.05) decrease in the expression level of ICTP compared with the control group. Conclusion EGCG can inhibit collagen degradation and improve the antierosive effect of dentine. [ABSTRACT FROM AUTHOR]

Objective: To observe the effect of green tea extractive epigallocatechin-3-gallate (EGCG) on degradation of collagen in dental erosion., Methods: Sixty-four volunteers with dental erosion were randomly divided into two groups. The custom fitted trays were made from the heat curable braces and were injected with carboxymethyl cellulose sodium (CMC) hydrogel in one group (control group) or CMC hydrogel with EGCG added in another (experimental group). These trays were used during sleep and removed from oral cavity in the next morning. The content of carboxy-terminal telopeptide of type I collagen (ICTP) were determined by radioimmunoassay kit at 1 d before the experiment, and 1, 2, 3, 4 weeks after the experiment., Results: Both the types and time showed significant effects on ICTP. The incubation in EGCG resulted in relatively rapid and significant (P < 0.05) decrease in the expression level of ICTP compared with the control group., Conclusion: EGCG can inhibit collagen degradation and improve the antierosive effect of dentine.

The purpose of the present study was to evaluate the efficacy of (-)-epigallocatechin-3-gallate (EGCG) in maintaining the vitality of human periodontal ligament (PDL) cells when used as a storage medium for avulsed teeth prior to replantation. Thirty freshly extracted single-rooted human teeth with closed apices were randomly assigned to three experimental groups with 10 samples per group and immersed in one of the storage media: EGCG, Hank's balanced salt solution (HBSS), or milk for 2 h. The PDL cells were dissociated by an enzyme treatment with collagenase and trypsin. The cells were then labeled with 0.4% Trypan blue for the determination of viability. The result showed that EGCG group had the highest percentage of cell viability, followed by HBSS and milk group, in descending order., (© 2011 John Wiley & Sons A/S.)