Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Anal Chim Acta ; 1324: 343089, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39218573

RESUMEN

BACKGROUND: Optical fiber sensors have been used to detect glucose owing to advantages such as low cost, small size, and ease of operation etc. phenylboronic acid is one of the commonly used receptors for glucose detection, however phenylboronic acid based regenerative optical fiber sensors are commonly cumulative regeneration, renewable regeneration sensor has been missing from the literature. RESULTS: In this work, instead of using phenylboronic acid, we synthesized succinylaminobenzenoboronic acid molecule (BPOA) by introducing a short chain containing carboxyl group at the other end of phenylboronic acid then covalently bonded BPOA on the surface of excessively tilted fiber grating (Ex-TFG). This provides a very stable platform for renewable regeneration and the regenerative buffer was also optimized. The proposed renewable regeneration method exhibited higher linearity and sensitivity (R2 = 0.9992, 8 pm/mM) in relative to the conventional cumulative regeneration method (R2 = 0.9718, 4.9 pm/mM). The binding affinity between BPOA and glucose was found to be almost constant over 140 bind/release cycles with a variation of less than 0.3 % relative standard deviation. SIGNIFICANCE: The regenerative and label-free sensing capacity of the proposed device provides a theoretical foundation for label-free saccharide detection and the development of wearable glucose monitoring devices based on fiber optic sensors.


Asunto(s)
Técnicas Biosensibles , Ácidos Borónicos , Fibras Ópticas , Ácidos Borónicos/química , Glucosa/análisis , Tecnología de Fibra Óptica , Límite de Detección
2.
Polymers (Basel) ; 16(10)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38794544

RESUMEN

As antibiotic resistance increasingly undermines traditional infection management strategies, there is a critical demand for innovative wound care solutions that address these emerging challenges. This study introduces a novel antibacterial wound dressing based on Cross-Linked Pullulan (Pul) and Polyhexamethylene Biguanide (PHMB) for enhanced wound management and infection control. The dressing's adsorption rate reached 200% of its original weight within 30 min, exceeded 300% after 5 h, and exhibited significant non-Newtonian fluid properties. The dressings were able to release the loaded medication completely within 20 min; additionally, the dressing demonstrated significant antibacterial activity against a broad spectrum of bacteria. Significantly, the therapeutic effects of the Pul-PHMB/GP dressing were evaluated in a mouse model. Compared to untreated wounds, wounds treated with Pul-PHMB/GP exhibited a significant gelation process within 5 min post-treatment and showed a significant increase in wound healing rate within 12 days. This powder preparation overcomes the limitations associated with liquid and gel dressings, notably in storage and precise application, preventing the premature expansion or dissolution often caused by PHMB in high-humidity environments. The powder form can transform into a gel upon contact with wound exudate, ensuring accurate coverage of irregular wounds, such as those from burns or pressure sores, and offers excellent chemical and physical stability in a dry state, which facilitates storage and transport. This makes the dressing particularly suitable for emergency medical care and precision therapy, significantly improving the efficiency and adaptability of wound treatment and providing robust support for clinical treatments and emergency responses.

3.
Bioconjug Chem ; 34(10): 1851-1860, 2023 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-37708446

RESUMEN

About 90% of cancer deaths worldwide are caused by the spread of cancer cells from the primary tumor to distant organs (metastasis). Therefore, there is an urgent need for an early diagnosis and treatment before cancer metastasis occurs. Lysosomes have emerged as attractive targets for cancer diagnosis and treatment because polar defects in lysosomes can induce apoptosis and cell death. Coumarin is a known polar-sensitive dye with good biocompatibility; because of this, we constructed two fluorescent probes of coumarin derivatives with the "D-π-A" structure, CouN-1 and CouN-2, through three simple reactions. In molecular design, due to morpholine's prominent lysosomal targeting characteristics, it was used as both lysosomal targeting motifs and an electron donor (D), while coumarin was used as an electron acceptor (A). The experimental results strongly proved that CouN-1 and CouN-2 have a good linear relationship with the polarity change of Δf = 0.209-0.308. In addition, both in vitro and in vivo imaging results have shown that CouN-1 and CouN-2 can specifically identify and monitor tumor sites. In the cell uptake and apoptosis experiments, the two probes also showed a strong antiproliferation effect on cancer cells. All of these characteristics demonstrated the potential of these two polarity-sensitive biological probes, CouN-1 and CouN-2, in the diagnosis and treatment of cancer.


Asunto(s)
Colorantes Fluorescentes , Neoplasias , Humanos , Colorantes Fluorescentes/química , Lisosomas/metabolismo , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Apoptosis , Cumarinas/uso terapéutico
4.
Chem Commun (Camb) ; 58(7): 1029-1032, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34951413

RESUMEN

Optically active linear polyurethane and a cyclic dimer were synthesized from 2,7-diisocyanatofluorene and 2,2'-dihydroxy-1,1'-binaphthyl. The circular dichroism (CD) spectral intensity of the polymer was amplified at a higher concentration through aggregate formation, while circularly polarized light (CPL) emission was not enhanced. The cyclic dimer's CPL emission was largely amplified (glum 1.1 × 10-2) due to intermolecular excimer formation through aggregation, while the CD intensity was not affected.


Asunto(s)
Colorantes Fluorescentes/química , Poliuretanos/química , Dicroismo Circular , Teoría Funcional de la Densidad , Dimerización , Naftoles/química , Estereoisomerismo
5.
J Chromatogr Sci ; 56(3): 195-201, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29206919

RESUMEN

A gas chromatographic-mass spectrometric (GC-MS) method was developed for the determination of four anthraquinones found in rhubarb. Chrysophanol, physcion, aloe-emodin and emodin were confirmed by GC-MS and the possible main cleavage pathways of fragment ions are discussed in this study. Rhubarb is a traditional Chinese medicinal herb which required an effective evaluation method to quantitate the four major active anthraquinone compounds described. The determinations of analytes were accomplished by GC-MS using osthole as an internal standard. MS detection was performed in selected ion monitoring mode to increase the sensitivity. The method was evaluated by a number of validation characteristics (precision, limit of detection, calibration range and recovery). The calibration ranges were all 3.2-30.0 µg/mL. This method was fully validated and showed good performances in terms of recovery (96.9-102.9%) and precision (1.4-2.9%). Finally, the method was applied to the analysis of four anthraquinones in rhubarb and its preparations in the first time.


Asunto(s)
Antraquinonas/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Rheum/química , Antraquinonas/química , Antraquinonas/aislamiento & purificación , Límite de Detección , Modelos Lineales , Preparaciones de Plantas/química , Reproducibilidad de los Resultados
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA