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1.
Biol Chem ; 405(2): 119-128, 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-36869860

ABSTRACT

Salvia miltiorrhiza (Salvia miltiorrhiza) root, as a traditional herb, is widely applied to pharmacotherapy for vascular system disease. In this study, we elucidate the therapy mechanism of Salvia miltiorrhiza by using a model of hindlimb ischemia. Blood perfusion measurement showed that intravenous administration of the Water Extract of Salvia miltiorrhiza (WES) could facilitate damaged hindlimb blood flow recovery and blood vessel regeneration. In vitro mRNA screen assay in cultured human umbilical vein endothelial cells (HUVECs) show that WES induced increased NOS3, VEGFA, and PLAU mRNA levels. Endothelial NOS (eNOS) promotor reporter analysis revealed that WES and the major ingredients danshensu (DSS) could enhance eNOS promoter activity. Additionally, we found that WES and its ingredients, including DSS, protocatechuic aldehyde (PAI), and salvianolic acid A (SaA), promoted HUVECs growth by the endothelial cell viability assays. A mechanistic approach confirmed that WES augments HUVECs proliferation through the activation of extracellular signal-regulated kinase (ERK) signal pathway. This study reveals that WES promotes ischemic remodeling and angiogenesis through its multiple principal ingredients, which target and regulate multiple sites of the network of the blood vessel endothelial cell regenerating process.


Subject(s)
Salvia miltiorrhiza , Animals , Humans , Ischemia/drug therapy , Human Umbilical Vein Endothelial Cells , Hindlimb , RNA, Messenger
2.
Biomacromolecules ; 24(2): 868-885, 2023 02 13.
Article in English | MEDLINE | ID: mdl-36692905

ABSTRACT

Conventional tumor chemotherapy is limited by its low therapeutic efficacy and side effects, which severely hold back its further application. Drug delivery systems (DDSs) based on nanomaterials have attracted wide interest in cancer treatment; especially, the system can realize efficient synergistic therapies. Here, we designed a smart hydrogel drug delivery system with multiple responses to enhance the tumor treatment effect. By cross-linking oxidized hydroxypropyl cellulose with carboxymethyl chitosan, an injectable hydrogel was obtained, into which artesunate (ART), ferroferric oxide (Fe3O4) nanoparticles, and black phosphorus nanosheets (BPs) were preloaded. This DDS has multiple functions including magnetic targeting, pH sensitivity, chemodynamic therapy, and photothermal response. This nanoparticle-composited hydrogel not only preserved excellent rheological properties but also allowed for an accurate stable drug release at tumor sites and synergistic effects of multiple therapies. The in vitro and in vivo experiments revealed that this DDS could efficiently eliminate the HepG2 tumor with good biocompatibility. Taken together, this study clarifies the possible antitumor mechanism of this ART-loaded nanoparticle-composited hydrogel and provides a new strategy for synergistic photothermal-chemo-chemodynamic therapy.


Subject(s)
Nanoparticles , Neoplasms , Humans , Doxorubicin/chemistry , Hydrogels/chemistry , Tumor Microenvironment , Neoplasms/drug therapy , Nanoparticles/chemistry , Magnetic Phenomena , Cell Line, Tumor
3.
Pharmacol Res ; 169: 105617, 2021 07.
Article in English | MEDLINE | ID: mdl-33872811

ABSTRACT

Traditional Chinese multi-herb-combined prescriptions usually show better performance than a single agent since a group of effective compounds interfere multiple disease-relevant targets simultaneously. Huang-Lian-Jie-Du decoction is a remedy made of four herbs that are widely used to treat oral ulcers, gingivitis, and periodontitis. However, the active ingredients and underlying mechanisms are not clear. To address these questions, we prepared a water extract solution of Huang-Lian-Jie-Du decoction (HLJDD), called it as WEH (Water Extract Solution of HLJDD), and used it to treat LPS-induced systemic inflammation in mice. We observed that WEH attenuated inflammatory responses including reducing production of cytokines, chemokines and interferons (IFNs), further attenuating emergency myelopoiesis, and preventing mice septic lethality. Upon LPS stimulation, mice pretreated with WEH increased circulating Ly6C- patrolling and splenic Ly6C+ inflammatory monocytes. The acute myelopoiesis related transcriptional factor profile was rearranged by WEH. Mechanistically we confirmed that WEH interrupted LPS/TLR4/CD14 signaling-mediated downstream signaling pathways through its nine principal ingredients, which blocked LPS stimulated divergent signaling cascades, such as activation of NF-κB, p38 MAPK, and ERK1/2. We conclude that the old remedy blunts LPS-induced "danger" signal recognition and transduction process at multiple sites. To translate our findings into clinical applications, we refined the crude extract into a pure multicomponent drug by directly mixing these nine chemical entities, which completely reproduced the effect of protecting mice from lethal septic shock. Finally, we reduced a large number of compounds within a multi-herb water extract to seven-chemical combination that exhibited superior therapeutic efficacy compared with WEH.


Subject(s)
Drugs, Chinese Herbal/therapeutic use , Inflammation/drug therapy , Monocytes/drug effects , Plant Extracts/therapeutic use , Transcription Factors/drug effects , Animals , Cellular Reprogramming/drug effects , Coptis chinensis , Drugs, Chinese Herbal/administration & dosage , Flow Cytometry , Gene Expression Regulation/drug effects , Male , Mice , Mice, Inbred C57BL , Microscopy, Fluorescence , Plant Extracts/administration & dosage , RAW 264.7 Cells/drug effects , Transcription Factors/metabolism
4.
J Sep Sci ; 40(23): 4563-4570, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28960849

ABSTRACT

We present a novel dispersive liquid-liquid microextraction method based on the solidification of deep eutectic solvent coupled with high-performance liquid chromatography with a variable-wavelength detection for the detection of five benzoylureas in real water samples. In this work, a green solvent consisting of 1-octyl-3-methylimidazolium chloride and 1-dodecanol was used as an extraction solvent, yielding the advantages of material stability, low density, and a suitable freezing point near room temperature. Parameters that significantly affect extraction efficiency were optimized by the one-factor-at-a-time approach. Under optimal conditions, the recoveries of five target compounds were obtained ranging from 87.39 to 98.05% with correlation coefficients ranging from 0.9994 to 0.9997 for pure water. The limits of detection were in the range of 0.09-0.16 µg/L. The enrichment factors were in the range of 171-188. Linearities were achieved in the range of 0.5-500 µg/L. The proposed method was successfully applied to determine benzoylureas in environmental water samples with a satisfactory recovery of approximately 81.38-97.67%.

5.
J Sep Sci ; 40(17): 3513-3521, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28675591

ABSTRACT

An ultrasound-assisted, hybrid ionic liquid, dispersive liquid-liquid microextraction method coupled to high-performance liquid chromatography with a variable-wavelength detector was developed to detect ten insecticides, including diflubenzuron, triflumuron, hexaflumuron, flufenoxuron, lufenuron, diafenthiuron, transfluthrin, fenpropathrin, γ-cyhalothrin and deltamethrin, in fruit juices. In this method, an appropriate extraction solvent was chosen based on the partition coefficient of the target compounds. A mixture of 1-octyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide was used as the extractant. The extraction efficiency was screened using Plackett-Burman design and optimized using central composite design. Under the optimal conditions, good linearity was obtained for all the analytes in the pure water model and the fruit juice samples. In pure water, the recoveries of the ten insecticides ranged from 85.7 to 108.9%, with relative standard deviations for one day ranging from 1.24 to 2.64%. The limits of detection were in the range of 0.19-0.69 µg/L, and the enrichment factors were in the range of 123-160. The logarithm of the n-octanol/water partition coefficient in this experiment is a useful reference to select a suitable extraction solvent, and the proposed technique was applied for the analysis of ten insecticides in fruit juice with satisfactory results.


Subject(s)
Food Contamination/analysis , Fruit and Vegetable Juices/analysis , Insecticides/analysis , Liquid Phase Microextraction , Chromatography, High Pressure Liquid , Diflubenzuron/analysis , Ionic Liquids , Ultrasonics
6.
J Sep Sci ; 39(22): 4422-4428, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27670749

ABSTRACT

In this study, a simple effervescence-assisted dispersive solid-phase extraction method was developed to detect fungicides in honey and juice. Most significantly, an innovative ionic-liquid-modified magnetic ß-cyclodextrin/attapulgite sorbent was used because its large specific surface area enhanced the extraction capacity and also led to facile separation. A one-factor-at-a-time approach and orthogonal design were employed to optimize the experimental parameters. Under the optimized conditions, the entire extraction procedure was completed within 3 min. In addition, the calibration curves exhibited good linearity, and high enrichment factors were achieved for pure water and honey samples. For the honey samples, the extraction efficiencies for the target fungicides ranged from 77.0 to 94.3% with relative standard deviations of 2.3-5.44%. The detection and quantitation limits were in the ranges of 0.07-0.38 and 0.23-1.27 µg/L, respectively. Finally, the developed technique was successfully applied to real samples, and satisfactory results were achieved. This analytical technique is cost-effective, environmentally friendly, and time-saving.


Subject(s)
Food Contamination/analysis , Fruit and Vegetable Juices/analysis , Fungicides, Industrial/analysis , Honey/analysis , Chromatography, High Pressure Liquid , Magnesium Compounds/chemistry , Silicon Compounds/chemistry , Solid Phase Extraction , beta-Cyclodextrins/chemistry
7.
J Sep Sci ; 39(2): 391-8, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26526571

ABSTRACT

A simple, sensitive, and efficient method of using a pipette vial to perform dispersive liquid-liquid microextraction based on the solidification of floating organic droplets was coupled with high-performance liquid chromatography (HPLC) and a diode array detector for the preconcentration and analysis of four benzoylurea insecticides in fruit juice. In this method, 1-dodecanol was used as an extractant, and a snipped pipette was used as an experimental vial to simplify the procedure of collecting and separating solidified extractant. The experimental parameters were optimized using a Plackett-Burman design and one-factor-at-a-time method. Under the optimal conditions in the water model, the limits of detection for analytes varied from 0.03 to 0.28 µg/L, and the enrichment factors ranged from 147 to 206. Linearity was achieved for diflubenzuron and flufenoxuron in a range of 0.5-500 µg/L, for hexaflumuron in a range of 1-500 µg/L, and for triflumuron in a range of 5-500 µg/L. The correlation coefficients for the analytes ranged from 0.9986 to 0.9994 with recoveries of 91.4-110.9%. Finally, the developed technique was successfully applied to fruit juice samples with acceptable results. The relative standard deviations of the analytes at two spiking levels (50 and 200 µg/L) varied between 0.2 and 4.5%.


Subject(s)
Benzamides/isolation & purification , Fruit and Vegetable Juices/analysis , Insecticides/isolation & purification , Liquid Phase Microextraction/methods , Phenylurea Compounds/isolation & purification , Benzamides/analysis , Chromatography, High Pressure Liquid , Insecticides/analysis , Limit of Detection , Liquid Phase Microextraction/instrumentation , Phenylurea Compounds/analysis
8.
J Sep Sci ; 37(18): 2545-51, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24947661

ABSTRACT

In this work, a novel liquid-phase microextraction approach using nonwoven polypropylene as the extraction solvent holder was developed. Nonwoven polypropylene, a hydrophobic material, is widely used in the cleanup of oil spills. Due to its large surface area, efficient, and full extraction can be achieved. Nonwoven polypropylene containing an ionic liquid was used to extract benzoylurea insecticides (diflubenzuron, teflubenzuron, flufenoxuron, and chlorfluazuron) through vortex-assisted liquid-liquid microextraction. The parameters that affected the extraction efficiency included the type and volume of the extractant, the extraction time, the time and solvent volume for desorption and the mass and surface area of the nonwoven polypropylene. Under the optimized conditions, good linearity was obtained, with coefficients of determination greater than 0.9996, and the limit of detections of these compounds, calculated at S/N = 3, were in the range of 0.73-5.0 ng/mL. The recoveries of the four insecticides at two spiked levels ranged from 93.3 to 102.0%, with relative standard deviations of less than 4.0%. The proposed method was then successfully used for the rapid determination of benzoylurea insecticides in spiked real water samples before liquid chromatographic analysis. The procedure is simple, inexpensive, easy to execute, and can be widely used.


Subject(s)
Insecticides/analysis , Liquid Phase Microextraction , Polypropylenes/chemistry , Water Pollutants, Chemical/analysis , Solvents/chemistry
9.
J Sep Sci ; 37(15): 1996-2001, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24824837

ABSTRACT

A dispersive liquid-liquid microextraction method based on the solidification of floating organic droplets was developed as a simple and sensitive method for the simultaneous determination of the concentrations of multiple fungicides (triazolone, chlorothalonil, cyprodinil, and trifloxystrobin) in water by high-performance liquid chromatography with variable-wavelength detection. After an approach varying one factor at a time was used, an orthogonal array design [L25 (5(5))] was employed to optimize the method and to determine the interactions between the parameters. The significance of the effects of the different factors was determined using analysis of variance. The results indicated that the extraction solvent volume significantly affects the efficiency of the extraction. Under optimal conditions, the relative standard deviation (n = 5) varied from 2.3 to 5.5% at 0.1 µg/mL for each analyte. Low limits of detection were obtained and ranged from 0.02 to 0.2 ng/mL. In addition, the proposed method was applied to the analysis of fungicides in real water samples. The results show that the dispersive liquid-liquid microextraction based on the solidification of floating organic droplets is a potential method for detecting fungicides in environmental water samples, with recoveries of the target analytes ranging from 70.1 to 102.5%.


Subject(s)
Fungicides, Industrial/analysis , Fungicides, Industrial/isolation & purification , Liquid Phase Microextraction/methods , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/isolation & purification , Chromatography, High Pressure Liquid/methods , Fresh Water/chemistry , Liquid Phase Microextraction/instrumentation , Rivers/chemistry
10.
ACS Appl Mater Interfaces ; 16(23): 29876-29890, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38829728

ABSTRACT

A novel therapeutic approach combining acupuncture and diclofenac sodium (DS) administration was established for the potential treatment for rheumatoid arthritis (RA). DS is a commonly used anti-inflammatory and analgesic drug but has short duration and adverse effects. Acupoints are critical linkages in the meridian system and are potential candidates for drug delivery. Herein, we fabricated a DS-loaded multilayer-modified acupuncture needle (DS-MMAN) and investigated its capacity for inhibiting RA. This DS-MMAN possesses sustained release properties and in vitro anti-inflammatory effects. Experimental results showed that the DS-MMAN with microdoses can enhance analgesia and efficiently relieve joint swelling compared to the oral or intra-articular administration of DS with gram-level doses. Moreover, the combination of acupoint and DS exerts a synergistic improvement in inflammation and joint damage. Cytokine and T cell analyses in the serum indicated that the application of DS-MMAN suppressed the levels of pro-inflammatory factors and increased the levels of anti-inflammatory factors. Furthermore, the acupoint administration via DS-MMAN could decrease the accumulation of DS in the liver and kidneys, which may express better therapeutic efficiency and low toxicity. The present study demonstrated that the acupuncture needle has the potential to build a bridge between acupuncture and medication, which would be a promising alternative to the combination of traditional and modern medicine.


Subject(s)
Acupuncture Therapy , Arthritis, Rheumatoid , Diclofenac , Needles , Diclofenac/administration & dosage , Diclofenac/pharmacology , Diclofenac/chemistry , Arthritis, Rheumatoid/therapy , Arthritis, Rheumatoid/drug therapy , Animals , Mice , Male , Drug Delivery Systems/instrumentation , Humans , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Rats
11.
Macromol Biosci ; 23(2): e2200430, 2023 02.
Article in English | MEDLINE | ID: mdl-36478660

ABSTRACT

Methicillin-resistant Staphylococcus aureus (MRSA) can induce multiple inflammations. The biofilm formed by MRSA is resistant to a variety of antibiotics and is extremely difficult to cure, which seriously threatens human health. Herein, a nanoparticle encapsulating berberine with polypyrrole core and pH-sensitive shell to provide chemo-photothermal dual therapy for MRSA infection is reported. By integrating photothermal agent polypyrrole, berberine, acid-degradable crosslinker, and acid-induced charge reversal polymer, the nanoparticle exhibited highly efficient MRSA infection treatment. In normal uninfected areas and bloodstream, nanoparticles showed negatively charged, demonstrating high biocompatibility and excellent hemocompatibility. However, once arriving at the MRSA infection site, the nanoparticle can penetrate and accumulate in the biofilm within 2 h. Simultaneously, berberine can be released into biofilm rapidly. Under the combined effect of photothermal response and berberine inhibition, 88.7% of the biofilm is removed at 1000 µg mL-1 . Moreover, the nanoparticles have an excellent inhibitory effect on biofilm formation, the biofilm inhibition capacity can reach up to 90.3%. Taken together, this pH-tunable nanoparticle can be employed as a new generation treatment strategy to fight against the fast-growing MRSA infection.


Subject(s)
Berberine , Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Humans , Polymers/pharmacology , Polymers/therapeutic use , Berberine/pharmacology , Berberine/therapeutic use , Pyrroles/pharmacology , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Biofilms , Staphylococcal Infections/drug therapy
12.
Int J Nanomedicine ; 15: 1771-1786, 2020.
Article in English | MEDLINE | ID: mdl-32214810

ABSTRACT

PURPOSE: In this study, pH-sensitive poly(2-ethyl-2-oxazoline)-poly(lactic acid)-poly(ß-amino ester) (PEOz-PLA-PBAE) triblock copolymers were synthesized and were conjugated with an antimalaria drug artesunate (ART), for inhibition of a colon cancer xenograft model. METHODS: The as-prepared polymer prodrugs are tended to self-assemble into polymeric micelles in aqueous milieu, with PEOz segment as hydrophilic shell and PLA-PBAE segment as hydrophobic core. RESULTS: The pH sensitivity of the as-prepared copolymers was confirmed by acid-base titration with pKb values around 6.5. The drug-conjugated polymer micelles showed high stability for at least 96 h in PBS and 37°C, respectively. The as-prepared copolymer prodrugs showed high drug loading content, with 9.57%±1.24% of drug loading for PEOz-PLA-PBAE-ART4. The conjugated ART could be released in a sustained and pH-dependent manner, with 92% of released drug at pH 6.0 and 57% of drug released at pH 7.4, respectively. In addition, in vitro experiments showed higher inhibitory effect of the prodrugs on rodent CT-26 cells than that of free ART. Animal studies also demonstrated the enhanced inhibitory efficacy of PEOz-PLA-PBAE-ART2 micelles on the growth of rodent xenograft tumor. CONCLUSION: The pH-responsive artesunate polymer prodrugs are promising candidates for colon cancer adjuvant therapy.


Subject(s)
Artesunate/pharmacokinetics , Colonic Neoplasms/drug therapy , Polymers/chemistry , Prodrugs/chemistry , Prodrugs/pharmacology , Animals , Artesunate/chemistry , Colonic Neoplasms/pathology , Drug Delivery Systems , Drug Liberation , Female , Humans , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Mice, Inbred BALB C , Micelles , Oxazoles/chemistry , Xenograft Model Antitumor Assays
14.
Food Chem ; 239: 797-805, 2018 Jan 15.
Article in English | MEDLINE | ID: mdl-28873637

ABSTRACT

A green, simple, inexpensive, and sensitive ionic liquid immobilized fabric phase sorptive extraction method coupled with high performance liquid chromatography was developed for rapid screening and simultaneous determination of four fungicides (azoxystrobin, chlorothalonil, cyprodinil and trifloxystrobin) residues in tea infusions. This IL modified extraction fiber is capable of extracting target analytes directly from complicated tea water matrices with the addition of surfactant. A series of extraction conditions were investigated by one-factor-at-a-time approach and orthogonal test. After a series experiments, the optimum conditions were found to be 10% [HIMIM]NTf2 as coating solution, 2min vortex time, 500µL acetonitrile as dispersive solvent and 2min desorption time. Under the above conditions, the proposed technique was applied to detect fungicides from real tea water samples with satisfactory results.


Subject(s)
Tea , Chromatography, High Pressure Liquid , Fungicides, Industrial , Ionic Liquids , Liquid Phase Microextraction , Surface-Active Agents , Water Pollutants, Chemical
15.
J Chromatogr A ; 1497: 1-8, 2017 May 12.
Article in English | MEDLINE | ID: mdl-28366570

ABSTRACT

Phytophagous mites are usually considered a difficult problem for agricultural planting, and acaricides are applied to control diseases and pests. However, the overdose and misusage of acaricides causes pesticide residues. In this work, a simple and practical ionic liquid-based TiO2 nanofluid, effervescence-assisted, dispersive liquid-liquid microextraction (EA-DLLME) method was developed to detect acaricides in honey and tea by high-performance liquid chromatography (HPLC-DAD). Oleophilic TiO2 nanoparticles were synthesized by a facile solvothermal method to obtain greater stability of the nanofluid. The experimental parameters were optimized by a one-factor-at-a-time approach and included the effervescent tablet composition, ionic liquid selection, extractant composition, nanofluid volume, extraction temperature, extraction time and desorption conditions. Under the optimized conditions, the linear ranges of this proposed method were 0.5-500µgL-1, with correlation coefficients in the range of 0.9985-1.0000. The extraction efficiencies for the target analytes varied from 70.70 to 84.58%. The detection and quantitation limits were in the ranges of 0.04-0.18µgL-1 and 0.13-0.60µgL-1, respectively. The intra- and inter-day relative standard deviations (n=3) were found to range from 2.32 to 5.71%, which showed perfect repeatability. Overall, the EA-DLLME method was time-saving and environmentally friendly, with future potential for microextraction.


Subject(s)
Acaricides/analysis , Ionic Liquids/chemistry , Liquid-Liquid Extraction/methods , Nanostructures/chemistry , Titanium/chemistry , Chromatography, High Pressure Liquid , Honey/analysis , Ions , Liquid Phase Microextraction/methods , Tablets , Tea/chemistry
16.
Talanta ; 166: 93-100, 2017 May 01.
Article in English | MEDLINE | ID: mdl-28213265

ABSTRACT

In this research, a novel method using magnetic mixed hemimicelles dispersive solid-phase extraction (MMHDSPE) based on C16mimBr-coated attapulgite/polyaniline-polypyrrole/Fe3O4 (ATP/PANI-PPY/Fe3O4) nanocomposites were investigated for enrichment and separation of three acaricides in fruit juice. In this method, we combined the simplicity and speed of dispersive solid-phase extraction, the advantages of mixed hemimicelles and the facility of the phase separation of the magnetic nanoparticles to develop a simple, rapid, sensitive, and effective method for detecting target analytes from the juice samples. ATP/PANI-PPY/Fe3O4 nanocomposites were successfully synthesized using a one-pot method. The as-prepared nanocomposite sorbents were characterized by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The experimental factors affecting the extraction efficiency including the sorbent type, amount of ATP/PANI-PPY/Fe3O4 nanocomposites, volume of ILs, sonication time, pH, and desorption conditions were optimized. Under the optimal conditions, good linearity was observed for all target analytes, with correlation coefficients (r2) ranging from 0.9994 to 0.9999; the limits of detection (LOD) were in the range of 0.16-0.57µgL-1, and the recoveries of analytes using the proposed method ranged between 88.67% and 95.10%. The sorbents exhibited excellent repeatability in the range of 1.83-4.24% in extracting the three target analytes. In addition, the intra-day and inter-day precision values were found to be in the range of 0.19-6.24% and 2.23-8.36%, respectively. The method was successfully applied to analyze fruit juice samples by rapid preconcentration of acaricides.


Subject(s)
Acaricides/analysis , Acaricides/isolation & purification , Chromatography, High Pressure Liquid/instrumentation , Fruit and Vegetable Juices/analysis , Ionic Liquids/chemistry , Magnetite Nanoparticles/chemistry , Nanocomposites/chemistry , Aniline Compounds/chemistry , Food Contamination/analysis , Hydrogen-Ion Concentration , Magnesium Compounds/chemistry , Micelles , Osmolar Concentration , Polymers/chemistry , Pyrroles/chemistry , Silicon Compounds/chemistry , Time Factors
17.
Food Chem ; 197 Pt B: 1064-72, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-26675842

ABSTRACT

A green, simple, inexpensive dispersive solid-phase microextraction method coupled with high-performance liquid chromatography was developed for rapid screening and selective recognition of benzoylurea insecticides (BUs) in honey and tea beverages. A novel adsorbent, ionic liquid (IL)-modified ß-cyclodextrin/attapulgite (ß-CD/ATP), was prepared by immobilizing IL on the surface of ß-CD/ATP. A series of demanding extraction conditions were investigated through the experimental design. Under optimum conditions, the limits of detection for the analytes varied from 0.12 to 0.21 µg L(-1). The enrichment factors ranged from 112 to 150 folds. Linearities in the range of 5-500 ng m L(-1) were achieved for four BUs, while the correlation coefficients ranged from 0.9997 to 1.0000 and the recoveries from 84.5% to 104.7%. The precision of this method for the four BUs corresponded to intra-day and inter-day RSDs% lower than 3.85%. Finally, the proposed technique was applied for the preconcentration of the BUs from real samples with satisfactory results.


Subject(s)
Honey/analysis , Insecticides/analysis , Ionic Liquids , Phenylurea Compounds/analysis , Solid Phase Microextraction/methods , Tea/chemistry , Chromatography, High Pressure Liquid/methods , Limit of Detection , Magnesium Compounds , Silicon Compounds , beta-Cyclodextrins
18.
Anal Chim Acta ; 906: 118-127, 2016 Feb 04.
Article in English | MEDLINE | ID: mdl-26772131

ABSTRACT

In this work, a novel effervescence-assisted microextraction technique was proposed for the detection of four fungicides. This method combines ionic liquid-based dispersive liquid-liquid microextraction with the magnetic retrieval of the extractant. A magnetic effervescent tablet composed of Fe3O4 magnetic nanoparticles, sodium carbonate, sodium dihydrogen phosphate and 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonimide) was used for extractant dispersion and retrieval. The main factors affecting the extraction efficiency were screened by a Plackett-Burman design and optimized by a central composite design. Under the optimum conditions, good linearity was obtained for all analytes in pure water model and real water samples. Just for the pure water, the recoveries were between 84.6% and 112.8%, the limits of detection were between 0.02 and 0.10 µg L(-1) and the intra-day precision and inter-day precision both are lower than 4.9%. This optimized method was successfully applied in the analysis of four fungicides (azoxystrobin, triazolone, cyprodinil, trifloxystrobin) in environmental water samples and the recoveries ranged between 70.7% and 105%. The procedure promising to be a time-saving, environmentally friendly, and efficient field sampling technique.


Subject(s)
Fungicides, Industrial/isolation & purification , Ionic Liquids/chemistry , Liquid Phase Microextraction/methods , Water Pollutants, Chemical/isolation & purification , Chromatography, High Pressure Liquid , Spectrophotometry, Ultraviolet
19.
Anal Chim Acta ; 934: 114-21, 2016 Aug 31.
Article in English | MEDLINE | ID: mdl-27506351

ABSTRACT

In this study, the superparamagnetic attapulgite/Fe3O4/polyaniline (ATP/Fe3O4/PANI) nanocomposites were successfully synthesized by a one-pot method. Fe (III) was applied as both the oxidant for the oxidative polymerization of aniline and the single iron source of Fe3O4 formed by the redox reaction between aniline and Fe (III). The ATP/Fe3O4/PANI was used as sorbent for magnetic dispersive solid phase extraction (MDSPE) of benzoylurea insecticides (BUs) in environmental water samples. The as-prepared nanocomposite sorbents were characterized by Fourier transform infrared spectra (FT-IR), X Ray diffraction (XRD), scanning electron microscopy(SEM), transmission electron microscopy (TEM), and vibrating sample magnetometry. Various experimental parameters affecting the ATP/Fe3O4/PANI-based MDSPE procedure, including the composition of the nanocomposite sorbents, amount of ATP/Fe3O4/PANI nanocomposites, vortex time, pH, and desorption conditions were investigated. Under the optimal conditions, a good linearity was observed for all target analytes, with correlation coefficients (r(2)) ranging from 0.9985 to 0.9997; the limits of detection (LOD) were in the range of 0.02-0.43 µg L(-1), and the recoveries of analytes using the proposed method ranged between 77.37% and 103.69%. The sorbents exhibited an excellent reproducibility in the range of 1.52-5.27% in extracting the five target analytes. In addition, the intra-day and inter-day precision values were found to be in the range of 0.78-6.86% and 1.66-8.41%, respectively. Finally, the proposed ATP/Fe3O4/PANI-based MDSPE method was successfully applied to analyze river water samples by rapid preconcentration of BUs.

20.
Anal Chim Acta ; 878: 131-9, 2015 Jun 09.
Article in English | MEDLINE | ID: mdl-26002334

ABSTRACT

A novel sorbent (ß-CD/ATP composite) for dispersive solid-phase extraction (d-SPE) prepared by bonding ß-cyclodextrin to modified attapulgite via silane coupling was used to determine the concentrations of four (fluoro)quinolones (Qs) in honey samples. The subsequent quantification of the Qs (ciprofloxacin, norfloxacin, ofloxacin, and gatifloxacin) was accomplished using high-performance liquid chromatography (HPLC) with ultraviolet detection after the d-SPE procedure. Parameters that may influence the extraction efficiency, such as type and volume of the eluent, type and amount of the sorbent, times of the vortex and sonication process, and pH of the sample, were investigated using batch and column procedures. The optimal experimental conditions (5 mL sample at pH 3, 4 mg of ß-CD/ATP composite as the sorbent, 200 µL of 40% ammonia in methanol as the eluent, with vortex time 60s and sonication time 6 min, and no addition of salt) were obtained from this statistical evaluation. The limits of detection (LODs) were determined to the range from 0.30 to 3.95 µg L(-1). Good recoveries (83.6-88.6%) were obtained under the optimum conditions, and the relative standard deviations (RSDs), which are used to indicate reproducibility, were less than 7.4%. The method was validated with three real honey samples, and the results demonstrated that ß-CD/ATP composite possessed a high adsorption capacity for Qs. Although the LODs were slightly higher than expected, this study confirmed the possibility of using cyclodextrin grafted palygorskite in analytical applications.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Honey/analysis , Magnesium Compounds/chemistry , Quinolones/isolation & purification , Silicon Compounds/chemistry , Solid Phase Extraction/methods , beta-Cyclodextrins/chemistry , Adsorption , Chromatography, High Pressure Liquid/methods , Halogenation , Limit of Detection , Reproducibility of Results
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