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1.
J Phys Chem Lett ; 15(19): 5137-5142, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38709498

ABSTRACT

The Brust-Schiffrin (BS) method for gold nanoparticle (Au NP) synthesis is celebrated for its ability to produce highly monodisperse NPs from toluene-water solutions, in contrast to aqueous methods, such as the Turkevich method. Despite the method's success, the actual formation mechanisms remain largely unknown due to difficulty in studying the intermediates with species-differentiating techniques such as mass spectrometry (MS) or nuclear magnetic resonance (NMR). The issue lies in the use of solvents poorly compatible with these techniques and the difficulty in differentiating useful intermediate species from side products and impurities in such one-pot reactions. Herein, we use our recently formulated fully aqueous BS reaction to study the formation mechanisms. MS is chiefly employed to capture the intermediate species, and the Au25(SR)18 nanocluster is used as a thermodynamically reliable end-point. We find that the BS method may comprise a unilateral complex-shedding stage in addition to the known thiol-etching stage.

2.
J Pharm Biomed Anal ; 245: 116191, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38728950

ABSTRACT

A method involving chitosan-assisted magnetic-stirring-enhanced mechanical amorphous dispersion extraction was developed and utilized to extract hydrophobic anthraquinones from Rhei Radix et Rhizoma prior to ultrahigh performance liquid chromatography analysis. Incorporating natural chitosan as a dispersant facilitated the extraction of hydrophobic anthraquinones using purified water, considerably enhancing the eco-friendliness of the extraction methodology. To optimize extraction efficiency, an extensive evaluation of the crucial parameters influencing rhubarb yield was conducted. Furthermore, a response surface methodology was applied to optimize the extraction conditions. Under these optimized conditions, the method exhibited linearity ranges of 0.1-100 µg/mL, with correlation coefficients between 0.9990 and 0.9998. The method's intraday (n = 6) and interday (n = 6) precision levels were maintained at ≤3.58%, which was considered to be within acceptable limits. The computed detection and quantification limits were 16.54-24.60 and 54.91-82.04 ng/mL, respectively. Consequently, this optimized method was effectively employed to extract five specific compounds (aloe-emodin, emodin, rhein, chrysophanol, and physcion) from Rhei Radix et Rhizoma, achieving recoveries ranging from 86.43% to 102.75%.


Subject(s)
Anthraquinones , Hydrophobic and Hydrophilic Interactions , Plants, Medicinal , Rheum , Anthraquinones/chemistry , Anthraquinones/analysis , Chromatography, High Pressure Liquid/methods , Rheum/chemistry , Plants, Medicinal/chemistry , Chitosan/chemistry , Phytochemicals/chemistry , Phytochemicals/analysis , Phytochemicals/isolation & purification , Water/chemistry , Emodin/analogs & derivatives , Emodin/chemistry , Emodin/analysis , Limit of Detection , Plant Extracts/chemistry
3.
Nat Prod Res ; : 1-8, 2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38572741

ABSTRACT

The phytochemical study of the fruits of Melia azedarach (Meliaceae) led to the isolation and characterisation of two novel natural limonoids1-deoxy- 3, 20-dicinnamoyl-11-methoxy-meliacarpinin (1) and 12ß- O- methyl nimbolinin A (2), along with twelve known limonoids. Its structure was identified by 1D- and 2D-NMR, HR-ESI-MS and comparison with published data. The anti-inflammatory effect of the compounds was measured in vitro in RAW 264.7 cells by evaluating the production of NO stimulated by LPS. Compounds 1, 8 and 14 indicated significant anti-inflammatory effect with inhibition rate of 11.76, 8.45 and 6.59 µM, respectively. Limonoid 1 significantly inhibited the production of NO, TNF-α and IL-1ß in RAW 264.7 cells. Therefore, limonoid derivative may be a promising source of bioactive metabolite for inflammatory diseases.

4.
Adv Mater ; 36(25): e2401002, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38521974

ABSTRACT

Metal nanoclusters (MNCs) can be synthesized with atomically precise structures and molecule formulae due to the rapid development of nanocluster science in recent decades. The ultrasmall size range (normally < 2 nm) endows MNCs with plenty of molecular-like properties, among which photoluminescent properties have aroused extensive attention. Tracing the research and development processes of luminescent nanoclusters, various photoluminescent analysis and characterization methods play a significant role in elucidating luminescent mechanism and analyzing luminescent properties. In this review, it is aimed to systematically summarize the normally used photoluminescent characterizations in MNCs including basic parameters and methods, such as excitation/emission wavelength, quantum yield, and lifetime. For each key parameter, first its definition and meaning is introduced and then the relevant characterization methods including measuring principles and the revelation of luminescent properties from the collected data are discussed. Then, it is discussed in details how to explore the luminescent mechanism of MNCs and construct NC-based applications based on the measured data. By means of these characterization strategies, the luminescent properties of MNCs and NC-based designs can be explained quantitatively and qualitatively. Hence, this review is expected to provide clear guidance for researchers to characterize luminescent MNCs and better understand the luminescent mechanism from the measured results.

5.
Anal Chim Acta ; 1297: 342359, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38438236

ABSTRACT

BACKGROUND: Microemulsion electrokinetic chromatography (MEEKC) is a mode of capillary electrophoresis with a wide range of applications in which microemulsion is utilized as background electrolyte to achieve the separation of analytes. Microemulsions are composed of oil droplets, aqueous buffer, surfactant, and co-surfactant. Currently, conventional organic reagents act as the most commonly used oil phase in microemulsions, which are unfriendly to the environment. Recently, deep eutectic solvent (DES) has become a new type of eco-friendly solvent due to its non-toxicity. Therefore, it is of great value to establish a new MEEKC method by replacing conventional organic reagents as the oil phase with DES. RESULTS: The novel DES/W MEEKC method was established for phenolic compounds in Senecio scandens samples. Single-factor experiments and response surface methodology were performed to systematically optimize the crucial parameters for the method, including the type and content of the oil phase, surfactant content, concentration of borax buffer, and pH of the background solution. Under the optimized conditions, satisfactory regression curves were established for all standard analytes with correlation coefficients ≥0.9990. The method featured high sensitivity and favorable accuracy, with the instrumental detection limit in the range of 0.22-1.04 µg/mL, and intraday and interday precision for migration time expressed as relative standard deviations of 0.18-0.82% and 1.25-2.50%, respectively. The DES/W MEEKC method was successfully applied to Senecio scandens with good recoveries of 87.72-106.99%. In conclusion, the newly established DES/W MEEKC method is highly efficient, green and environmentally friendly. SIGNIFICANCE: DES is considered a green and efficient solvent. The DES/W MEEKC method is highly efficient and environmentally friendly. Actually, the method provides a novel and effective analytical tool for the simultaneous separation and determination of multiple phenolic compounds, especially in complex plant matrices. In the future, the DES/W MEEKC method still has the prospect of being widely used in the separation of other complex phytochemicals.

6.
Int J Rheum Dis ; 27(3): e15088, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38454192

ABSTRACT

BACKGROUND: Sjögren's Syndrome (SS), mainly affecting women in their midlife, is characterized by persistent inflammation in glands producing tears and saliva, often leading to significant complications. This study investigates the differences in autonomic system functioning between individuals with SS and healthy controls. METHODS: From April 2019 to December 2022, 329 diagnosed primary SS (pSS) patients and 30 healthy controls were enrolled at Taipei Veterans General Hospital, Taipei, Taiwan. The study assessed autonomic nervous system functioning using various HRV metrics. Participants were divided based on age and AECG criteria, including salivary gland biopsy and autoantibody status. RESULTS: Significant differences in Heart Rate Variability (HRV) were observed between pSS patients and healthy controls. The total power index was notably lower in pSS patients (4.98 ± 1.29) than in controls (5.54 ± 1.21, p = .022). Additionally, Vagal (VAG) activity was significantly reduced in the pSS group (4.95 ± 1.33) compared to the healthy control group (5.47 ± 1.19, p = .041). Age-stratified analysis highlighted that the ≤50 years pSS group had a higher heart rate (77.74 ± 10.42) compared to the >50 years group (73.86 ± 10.35, p = .005). This group also showed a higher total power index (5.78 ± 1.30) versus the >50 years group (4.68 ± 1.19, p < .001), and significantly lower VAG activity (4.70 ± 1.26, p = .007) compared to healthy controls. Furthermore, the Standard Deviation of Normal-to-Normal Intervals (SDNN) was greater in the ≤50 years SS group (44.45 ± 37.12) than in the >50 years group (33.51 ± 26.18, p = .007). In pSS patients, those positive for both salivary gland biopsy and autoantibodies demonstrated a lower Total Power (4.25 ± 1.32) and R-wave validity (93.50 ± 4.79, p < .05) than other groups, suggesting more severe autonomic imbalance. The R-R interval variation (RRIV) was also significantly higher in this dual-positive group (696.10 ± 975.41, p < .05). Additionally, the ESSPRI for dryness was markedly higher in the dual-positive group (8.10 ± 1.45, p < .05), indicating more severe symptoms. These findings reveal significant variations in autonomic function in SS patients, especially in those with dual-positive biopsy and autoantibody status. CONCLUSION: This study demonstrates significant autonomic dysfunction in pSS patients compared to healthy controls, particularly in those positive for both salivary gland biopsy and autoantibodies. The age-stratified analysis further emphasizes the impact of aging on autonomic system functioning in pSS, suggesting a need for age-specific management approaches in pSS patient care.


Subject(s)
Autonomic Nervous System Diseases , Sjogren's Syndrome , Humans , Female , Middle Aged , Sjogren's Syndrome/complications , Heart Rate , Saliva , Tears , Autoantibodies
7.
Neurosci Res ; 200: 8-19, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37926219

ABSTRACT

Spiral ganglion neurons (SGNs) transmit sound signals received by hair cells to the auditory center to produce hearing. The quantity and function are important for maintaining normal hearing function. Limited by the regenerative capacity, SGNs are unable to regenerate spontaneously after injury. Various neurotrophic factors play an important role in the regeneration process. Neuritin is a neurite growth factor that plays an important role in neural plasticity and nerve injury repair. In this study, we used bioinformatics analysis to show that neuritin was negatively correlated with cochlear damage. Then, we aimed to establish a cochlear spiral ganglion-specific sensorineural deafness model in gerbils using ouabain and determine the effects of exogenous neuritin protein in protecting damaged cochlear SGNs and repairing damaged auditory nerve function. The provides a new research strategy and scientific basis for the prevention and treatment of sensorineural deafness caused by the loss of SGNs. We were discovered that neuritin is expressed throughout the development of the gerbil cochlea, primarily in the SGNs and Corti regions. The expression of neuritin was negatively correlated with the sensorineural deafness induced by ouabain. In vitro and in vivo revealed that neuritin significantly maintained the number and arrangement of SGNs and nerve fibers in the damaged cochlea and effectively protected the high-frequency listening function of gerbils.


Subject(s)
Deafness , Hearing Loss, Sensorineural , Animals , Spiral Ganglion/metabolism , Gerbillinae , Ouabain/pharmacology , Cochlea , Neurons , Deafness/chemically induced , Deafness/metabolism , Denervation
8.
J Chromatogr A ; 1714: 464563, 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38101248

ABSTRACT

An on-line enrichment and separation of multiple derivatized monosaccharides with cyclodextrin-encapsulated sweeping (CDES) by micellar electrokinetic chromatography (MEKC) was presented. Five monosaccharides (L-(-)-Mannose, D-(+)-Glucose, D-(-)-Ribose, D-(+)-Xylose, and L-(+)-Rhamnose) were derivatized with 1-phenyl-3-methyl-5-pyrazolone, subsequently concentrated and separated by MEKC. The optimized conditions were as follows: 50 mM phosphoric acid (PA), 100 mM sodium dodecyl sulfate (SDS), and 30 % (v/v) methanol in background solution; 140 s injection of sample solution containing 50 mM CD and 100 mM PA, followed by 90 s injection of 40 mM SDS solution. Under the optimized conditions, the correlation coefficients ≥ 0.9953, and the limits of detection ranged from 4.2 to 7.4 ng/mL. Relative standard deviation values ranged from 0.24-4.23 %, and sensitivity enrichment factors were in the range of 53-82 compared with typical injection (50 mbar, 3 s). The CDES-MEKC method was successfully applied to Jujube with good recoveries of 84.22-104.33 %. The method provides new ideas for the on-line enrichment and detection of trace monosaccharides and even other target analytes in foods with complex matrices.


Subject(s)
Chromatography, Micellar Electrokinetic Capillary , Cyclodextrins , Chromatography, Micellar Electrokinetic Capillary/methods , Cyclodextrins/chemistry , Monosaccharides , Fruit , Micelles
9.
Food Res Int ; 175: 113769, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38129060

ABSTRACT

This experiment aimed to establish a green, simple and highly sensitive method (supercritical fluid chromatography (SFC) coupled with ion mobility quadrupole time-of-flight mass spectrometry (IM-Q-TOF/MS)) for the detection of multiple pesticides in foods. During the experiments, several important SFC parameters, such as stationary phase, modifier, make-up solution, back-temperature and back-pressure were optimized. Here, single-field collision cross section (CCS) values and multifield CCS values of 20 pesticides were examined by IM-Q-TOF/MS as highly specific parameters with excellent experimental precision. In addition, based on accurate mass matching and fragment ion comparison, mass fragments were obtained by IM-Q-TOF/MS, which elucidated the regularities of compound structure and characteristic fragment ions. Under the optimized conditions, satisfactory linearity (R2 ≥ 0.9989) and recoveries (79.60 % to 112.97 %) were obtained. The intra- and interday precisions were favorable, with RSDs lower than 4.91 and 7.65 %, respectively. Additionally, the method showed low limits of detection (0.1-8.8 ng/mL). The proposed method has been successfully applied to the highly sensitive detection of phenylurea herbicide, triazine herbicides, organophosphorus pesticide, pyrethroid insecticide and acaricide in yam and potato.


Subject(s)
Chromatography, Supercritical Fluid , Pesticide Residues , Pesticides , Pesticide Residues/analysis , Pesticides/analysis , Chromatography, Supercritical Fluid/methods , Organophosphorus Compounds/analysis , Mass Spectrometry
10.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1020437

ABSTRACT

Objective:To develop an evaluation index system on health education effect for adolescents with type 1 diabetes mellitus (T1DM).Methods:Using "knowledge-attitude/belief-practice"model and health belief model as the theoretical framework, the first draft of the expert consulation questionnaire for evaluation index system on health education effect for adolescents with type 1 diabetes mellitus was drawn up through literature review, qualitative interview, and repeated discussions between groups. Two rounds of expert consultation were conducted. The results of the consulation were sorted and analyzed, the index structure, item content, and sequence were discussed repeatedly, and the evaluation index system on health education effect for adolescents with T1DM was determined, and the analytic hierarchy process was used to determine its weight.Results:A total of 21 female experts participated in two rounds of survey whose age was (43.48 ± 5.84) years old. The questionnaire response rates of the two rounds of expert consultations were 84.00%(21/25) and 85.71%(18/21), the authoritative coefficients were 0.96 and 0.97, the Kendall coordination were 0.181 and 0.256, respectively ( P<0.05). The consistency test of the weight of each indicator showed that the consistency ratios were all <0.1. The evaluation index system on health education effect for adolescents with T1DM was constructed with 5 first-level indicators (health knowledge, health belief, health practice, physiological indexes and health education satisfaction), 38 second-level indicators. Conclusions:The method used to construct the evaluation index system on health education effect for adolescents with T1DM was highly scientific and reliable, which provides the basis for clinical nurses to evaluate and monitor the effect of health education in adolescents with T1DM.

11.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1027395

ABSTRACT

Objective:To explore the effects of estrogen receptor α (ERα) encoded by protein encoding gene ESR1 on the radiation resistance of breast cancer cells and their molecular mechanisms.Methods:The ESR1 overexpression plasmid was transfected into estrogen receptor (ER)-negative breast cancer cells. Then, the shRNA-ESR1 vector was introduced into ER-positive cell to establish models with different phenotype. The ATG5 mRNA level and protein expression levels of LC3B-I, LC3B-II, P62, FIP200, ATG5, ATG7, ATG12, Beclin1, ULK1 were detected using qPCR and Western blot techniques. Cell death was measured using flow cytometry. The radiation sensitivity was determined through the colony formation assay. The mortality of breast cancer cells under the autophagy gene knockdown and overexpression or treated with estrogen receptor inhibitor (TAM) combined with ionizing radiation were detected by trypan blue staining.Results:Under the condition of 8 Gy X-ray irradiation, the knockdown of ESR1 in ER-positive ZR75 breast cancer cells promoted cell death ( t = 3.49, 3.13, P < 0.05), while the overexpression of ESR1 in ER-negative MDA-MB-231 breast cancer cells inhibited cell death ( t = 4.16, 7.48, P < 0.05). Compared to the control group, the treatment with chloroquine increased the number of formed colonies of ESR1 knockdown ZR75 cells ( t = 8.49, P < 0.05), and inhibiting autophagy could reduce the death of ZR75 cells caused by ESR1 silencing. Under the treatment with ionizing radiation, the overexpression of ESR1 in MDA-MB-231 cells promoted protective autophagy, which, however, was reduced after ESR1 knockdown in ZR75 cells. Furthermore, it was observed that the knockdown of ATG5 in ZR75 cells was associated with reduced autophagy and an increase in cell death ( t = 4.19, 6.39, P < 0.05). In contrast, the overexpression of ATG5 in ZR75 cells reversed the increase in cell death caused by ESR1 knockdown ( t = 1.70, 4.65, P < 0.05). After the treatment of ER-positive ZR75 breast cancer cells with TAM, the expressions of ATG5 and ATG12 decreased, suggesting inhibited autophagy and an increase in cell death ( t = 18.70, P < 0.05). Furthermore, these processes were promoted by ionizing radiation ( t = 16.82, P < 0.05). Conclusions:The estrogen receptor encoded by ESR1 promotes protective autophagy of ER-positive breast cancer cells by increasing ATG5, further leading to radiation resistance in ER-positive breast cancer cells. Treatment with tamoxifen combined with ionizing radiation can increase the radiation sensitivity of ER-positive breast cancer cells.

12.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1006843

ABSTRACT

Objective To explore the material basis and mechanism of the Chinese medicine Shenmajingfu granules in the treatment of cerebral infarction. Methods The potential active ingredients and targets of Shenmajingfu granules were retrieved through TCMSP, ETCM database and TCM Database. The related target genes of cerebral infarction were searched from OMIM database. The common targets of Shenmajingfu granules and cerebral infarction were obtained by the intersection method. Cytoscape was used to construct active components of Shenmajingfu granules-targets network. Protein-protein interaction network was constructed by STRING software. DAVID database was used for GO and KEGG enrichment analysis. Results The 183 potential active ingredients of Shenmajingfu granules were screened out. 1785 potential targets were screened in the TCMSP database, including 30 targets related to cerebral infarction. These target genes were mainly involved in the inflammatory response and apoptosis process, involving the TNF signaling pathway, HIF-1 signaling pathway and NF-κB signaling pathway. Conclusion The therapeutic effect of Shenmajingfu granules on cerebral infarction may be related to the regulation of inflammatory response, improvement of impaired neurological function and protection of cerebral ischemia-reperfusion injury.

13.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1019192

ABSTRACT

Objective To observe the effect of ultrasound-guided iliopsoas plane block(IPB)on the quality of postoperative recovery in patients undergoing hip arthroplasty.Methods Sixty patients who underwent hip arthroplasty were selected,37 males and 23 females,aged 40-79 years,BMI 18-30 kg/m2,ASA physical status Ⅰ-Ⅲ.The patients were divided into two groups by random number table method:the iliopsoas plane block group(group IPB)and the femoral nerve block(FNB)group(group FNB),30 pa-tients in each group.Before anesthesia induction,IPB was performed with 0.5%ropivacaine 10 ml and lat-eral femoral cutaneous nerve block was performed with 0.5%ropivacaine 5 ml in group IPB.And FNB was performed with 0.5%ropivacaine 10 ml and lateral femoral cutaneous nerve block was performed with 0.5%ropivacaine 5 ml in group FNB.The dosages of propofol,remifentanil,and cis-atracurium during operation were recorded.The quality of recovery-15(QoR-15)scale was evaluated preoperatively and postoperatively 1 day,2 and 3 days.The max VAS(VASmax)pain score and manual muscle test(MMT)score of quadri-ceps muscle were recorded 12,24,and 48 hours after surgery.The time of getting out of bed for the first time,opioid dosage,and patient satisfaction were recorded.The incidence of nerve injury,vascular injury,puncture site infection,and local anesthetic poisoning were recorded.The postoperative complications of diz-ziness,nausea and vomiting,deep vein thromboses,and elirium were also recorded.Results There was no significant difference in the dosage of propofol,remifentanil,and cis-atracurium between the two groups.Compared with group FNB,the QoR-15 scale score in group IPB was significantly higher 1 day,2 and 3 days after operation(P<0.05).Compared with group FNB,the MMT scores of quadriceps muscle was sig-nificantly higher in group IPB 12 and 24 hours after surgery(P<0.05),and the first time of getting out of bed was shortened in group IPB(P<0.05).However,there were no significant differences in the VASmax pain score,MMT score of quadriceps muscle 48 hours after surgery,opioid dosage,and patient satisfaction between the two groups.No nerve block related complications were found in both groups.There were no sig-nificant differences in postoperative complications between the two groups.Conclusion The iliopsoas plane block can improve the quality of postoperative recovery and accelerate the recovery of patients with hip re-placement,and the effect is better than that of femoral nerve block.

14.
Urology ; 182: 196-203, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37673407

ABSTRACT

OBJECTIVE: To demonstrate the feasibility of a modified midurethral sling+hemolock fixation technique for treating male urinary incontinence. This study aims to provide a preliminary assessment of the short-term clinical efficacy of this technique. METHODS: We collected the clinical data of patients treated with modified sling midurethral suspension+ hemolock fixation technique. The primary evaluation criteria were surgery-related indicators and daily urinal pad usage by patients before and after treatment, and the secondary evaluation criteria were the corresponding incontinence scores and the results of surgery-related questionnaires. RESULTS: Follow-up 1-7months, eight patients achieved a clinical cure. Follow-up 1month after surgery showed that two patients (25.0%) used one pad daily and six patients (75.0%) did not need pads. The incontinence quality of life questionnaire (I-QOL) scores were (86.0 ± 7.0) and (89.0 ± 3.0) at three postoperative days and one postoperative month, respectively, which were significantly higher than the preoperative scores (26.0 ± 6.0) (P <.05). The scores of the International Continence Control Association Incontinence Questionnaire Short Form (ICI-Q-SF) at three postoperative days and one postoperative month were (4.0 ± 2.0) and (4.0 ± 1.0), respectively, which were significantly lower than the preoperative scores of (18.0 ± 1.0) (P <.05). Besides, the results of the surgery-related questionnaires were positive. CONCLUSION: The short-term efficacy of the modified sling midurethral suspension+ hemolock fixation technique for the treatment of male urinary incontinence patients is safe, effective, minimally invasive, and has few complications. However, further validation in large samples, randomized, comparative, and longer-term follow-up studies is still needed.


Subject(s)
Suburethral Slings , Urinary Incontinence, Stress , Urinary Incontinence , Humans , Male , Follow-Up Studies , Quality of Life , Pilot Projects , Urinary Incontinence, Stress/surgery , Urinary Incontinence, Stress/etiology , Urinary Incontinence/surgery , Urinary Incontinence/etiology , Treatment Outcome , Suburethral Slings/adverse effects
15.
J Chromatogr A ; 1706: 464258, 2023 Sep 13.
Article in English | MEDLINE | ID: mdl-37544236

ABSTRACT

A novel online two-step pressure injection-assisted stacking preconcentration method, which involves sweeping and affinity micelles in micellar electrokinetic chromatography was developed to simultaneously measure various organic anions. The micellar solution was a mixed solution that contained 0.3 mM didodecyldimethylammonium bromide and 20 mM borax. After the micellar solution was injected for 60 s, the tested analytes prepared in 20 mM borax were introduced into the capillary for 150 s. The key experimental factors that influenced the separation and sensitivity were investigated and optimized, including the concentration and injection time of the micellar solution, the concentration of borax in the sample solution, the concentration of sodium dodecyl sulfate and borax in the background electrolyte (BGE), the content of acetonitrile in the BGE and the injection time of the sample solution. Compared with typical injection methods, this method achieved sensitivity enhancement factors ranging from 85 to 97 under optimized conditions. Good linearity for matrix-matched calibration was established for all analytes with R2 values of 0.9986-0.9996. The intraday (n = 6) and interday (n = 6) precisions of the method were less than 2.85% when expressed as relative standard deviations. When the method was applied to analyze rice and dried ginger samples, analyte recoveries ranged from 85.81% to 106.59%. Through sweeping and affinity micelles, stacking preconcentration method was successfully employed to analyze trace amounts of fenoprop and 2,4-dichlorophenoxyacetic acid in rice and dried ginger samples.


Subject(s)
Chromatography, Micellar Electrokinetic Capillary , Herbicides , Herbicides/analysis , Chromatography, Micellar Electrokinetic Capillary/methods , Micelles , Anions
16.
J Chromatogr A ; 1702: 464090, 2023 Aug 02.
Article in English | MEDLINE | ID: mdl-37245356

ABSTRACT

A unique and effective comprehensive two-dimensional liquid chromatography system was established and applied for the analysis of bioactive components in honeysuckle. Under the optimal conditions, Eclipse Plus C18 (2.1 × 100 mm, 3.5 µm, Agilent) and SB-C18 (4.6 × 50 mm, 1.8 µm, Agilent) columns were chosen for the first dimension (1D) and the second dimension (2D) separation. The optimal flow rates of 1D and 2D were 0.12 mL/min and 2.0 mL/min, respectively. Additionally, the proportion of organic solution was optimized to enhance orthogonality and integrated shift, and full gradient elution mode was adopted to improve chromatographic resolution. Furthermore, a total of 57 compounds were identified by molecular weight, retention time and collision cross-section value obtained from ion mobility mass spectrometry. Based on the data obtained from the principal component analysis, partial least squares discriminant analysis, and hierarchical cluster analysis, the categories of honeysuckle in different regions were significantly different. Moreover, the half maximal inhibitory concentration values of most samples were between 0.37 and 1.55 mg/mL, and most samples were potent α-glucosidase inhibitors, which is better for the evaluation of the quality of drugs from two aspects of substance content and activity.


Subject(s)
Lonicera , Chemometrics , Chromatography, High Pressure Liquid/methods , Mass Spectrometry/methods
17.
Food Chem ; 417: 135894, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-36917908

ABSTRACT

In this study, a cyclodextrin aqueous solution was used as an environmentally friendly eluent to simultaneously extract active and toxic compounds from food matrices with the aid of nanographite-assisted matrix solid phase dispersion microextraction (NG-MSPDM). The NG-MSPDM procedure was optimized by single-factor experiments and response surface methodology to obtain optimum conditions. The proposed method achieved excellent linearity at 0.10-20 µg/mL for all target analytes with a coefficient of correction (R2) ≥ 0.9909, limits of detection < 52.01 ng/mL, satisfactory reproducibility below 3.21 %, and acceptable recoveries of 82.0-112 %. To accurately determine the target components in the complex matrix, collision cross-section values of the analytes were obtained using ion mobility quadrupole time-of-flight mass spectrometry (IM-Q-TOF/MS). Results indicated that the NG-MSPDM method successfully achieved the simultaneous extraction of flavonoids and phenoxyacetic herbicides from Alpinia officinarum.


Subject(s)
Food , Solid Phase Microextraction , Chromatography, High Pressure Liquid/methods , Reproducibility of Results , Solid Phase Extraction/methods , Solid Phase Microextraction/methods , Solvents/chemistry , Nanostructures , Graphite/chemistry
18.
Int J Biol Macromol ; 227: 986-1000, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36464194

ABSTRACT

The mixed enzymes-assisted mechanical bio-extraction method was first used to extract polysaccharides from Dendrobium officinale. Different parameters including the ratio of enzyme, the amount of enzyme, the grinding time, the extraction time and the solid/liquid ratio were investigated by single factor experiments and multifactorial experiments. Through the response surface methodology the optimal extraction conditions were obtained with the ratio of cellulase to pectinase was 2: 1 and total amount of enzyme was 0.23 mg, the grinding time of 11.48 min, the extraction time of 5.99 min. The obtained polysaccharide extracts were hydrolyzed and derivatized and then injected into high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF/MS) for monosaccharide composition analysis. After optimization of the chromatographic conditions (including mobile phase and column), twelve monosaccharides were successfully determined within 20 min. The proposed method provided satisfactory linearity with the correlation coefficients higher than 0.99, suitable recoveries (81.46-114.92 %), acceptable reproducibility ranging from 0.06 % to 4.77 %, low limits of detection (0.70-45.45 ng/mL). Compared with other methods, this method makes the extraction efficiency much higher and has the advantages of simple operation, environmental friendliness and mild extraction conditions. Therefore, this method can be used for the extraction of polysaccharides from plants and the determination of monosaccharides and has the potential to be used in more areas.


Subject(s)
Dendrobium , Monosaccharides , Monosaccharides/analysis , Chromatography, High Pressure Liquid/methods , Dendrobium/chemistry , Reproducibility of Results , Polysaccharides/chemistry
19.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-990401

ABSTRACT

This paper reviewed the definition, competence and training status of "dual-qualification" nursing teachers at home and abroad from several aspects including pre-service teacher preparation, entry qualification, in-service training and performance assessment and bring up some relevant problems and countermeasures of our country. It is expected to provide references for the construction of "dual-qualification" nursing faculty in China.

20.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1028414

ABSTRACT

Objective:To determine the median effective dose (ED 50) of ciprofol inhibiting responses to insertion of laryngeal mask airway in the patients when combined with alfentanil. Methods:American Society of Anesthesiologists Physical Status classification Ⅰ or Ⅱ patients of either sex, aged 40-64 yr, with body mass index of 20-30 kg/m 2, undergoing elective general anesthesia, were enrolled. Midazolam 0.025 mg/kg was intravenously injected for anesthesia induction, the baseline mean arterial pressure and heart rate were recorded 5 min later, and the average value of three times was considered as the baseline value. Ciprofol and alfentanil 10 μg/kg were intravenously injected in sequence, rocuronium 0.6 mg/kg was intravenously injected when BIS value < 60, 2 min later a laryngeal mask airway was placed, and mechanical ventilation was performed. Positive response was defined as increase in the maximum mean arterial blood pressure or heart rate more than or equal to 20% of the baseline value within 3 min after placement of the laryngeal mask airway or as the occurrence of body movement, bucking, frowning, mouth and face twitching, tearing, laryngospasm or the BIS value failing to drop below 60. The study was performed by the Dixon′s up-and-down method. The initial dose of ciprofol was 0.4 mg/kg, and the ratio between the two successive doses was 1.1. If a positive response occurred, the dose was increased in the next patient, otherwise the dose was reduced. The ED 50 and 95% confidence interval of ciprofol inhibiting responses to insertion of laryngeal mask airway were calculated by the probit method. Results:The ED 50(95% confidence interval) of ciprofol inhibiting responses to insertion of laryngeal mask airway was 0.291(0.231-0.318) mg/kg when combined with alfentanil 10 μg/kg. Conclusions:The ED 50 of ciprofol inhibiting responses to insertion of laryngeal mask airway is 0.291 mg/kg in the patients when combined with alfentanil 10 μg/kg.

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