•MSPD was developed for the microextraction of inorganic iodine and iodinated amino acids.•Molecular sieves were characterised as the dispersion sorbents.•Ionic liquids were chosen as the elution ...solvents.•The method was applied to determine the analytes in different kinds of seaweeds.
This study presents an effective method of using miniaturized matrix solid phase dispersion (MSPD) for the microextraction of inorganic iodine and iodinated amino acids from seaweed samples. Quantification of the target analytes was performed by ultrahigh performance liquid chromatography with UV detection. Molecular sieve (SBA-15) was chosen as the dispersing adsorbent with an ionic liquid (1-dodecyl-3-methylimidazolium bromide) as the elution solvent. The experimental conditions for the MSPD, such as the type of sorbent, ratio of sorbent to sample, type and concentration of the elution solvent, and grinding time were evaluated and optimized. Under the final working conditions, good recoveries were obtained in the range of 86.5–95.4%, with relative standard deviation values below 6.0% in all cases. The limits of detection and limits of quantitation were in the ranges of 3.7–16.7ng/mL and 12.4ng/mL, respectively. Compared with common ultrasound assisted extraction, the advantages of this green approach are low consumption of the sorbent and solvent, short extraction time and good selectivity, even in complicated matrices. The proposed SBA-15-based MSPD method was successfully applied to the microextraction of potassium iodide, 3-iodo-l-tyrosine, and 3,5-diiodo-l-tyrosine from kelp, nori and undaria pinnatifida, respectively.
•A novel application of trace MSPD using β-CD as sorbent is presented.•The proposed method involves the use of UHPLC-UV, Q-TOF/MS and NMR.•The innovative method was efficient and economic for isomers ...extraction.•The method was applied to a determination of honeysuckle samples.
Here, a novel β-cyclodextrin (β-CD) based trace matrix solid-phase dispersion (MSPD) method was developed to extract isomers from different honeysuckle samples using ultrahigh performance liquid chromatography. The structures of the analytes were characterized and determined via quadrupole time-of-flight tandem mass spectrometry and nuclear magnetic resonance. Under optimum conditions, 25mg of sample was dispersed with 75mg of β-CD, and 0.5mL of methanol was used as the elution solvent. The proposed method produced a good linearity (r2>0.99) for the isomers, with limits of detection ranging from 1.62 to 3.33ng/mL. The average recovery values that were obtained from analyzing the spiked samples were calculated to be in the range of 87.04–105.20%. Moreover, the trace MSPD method required less reagents and a shorter extraction time in comparison with the traditional pharmacopoeia method and other reported approaches. The developed method was successfully applied for the determination of three real honeysuckle samples that were collected from different cultivated areas.
•MCM-41 silica was used as an efficient adsorbent in mini-SPE procedure.•An effective UHPLC-Q-TOF/MS method for analysis of macrolide antibiotics has been presented.•The proposed method was simple, ...fast, low-cost and high sensitivity.
A simple and effective method of miniaturized solid-phase extraction (mini-SPE) was developed for the simultaneous purification and enrichment of macrolide antibiotics (MACs) (i.e. azithromycin, clarithromycin, erythromycin, lincomycin and roxithromycin) from honey and skim milk. Mesoporous MCM-41 silica was synthesized and used as sorbent in mini-SPE. Several key parameters affecting the performance of mini-SPE procedure were thoroughly investigated, including sorbent materials, amount of sorbent and elution solvents. Under the optimized condition, satisfactory linearity (r2 > 0.99), acceptable precision (RSDs, 0.3–7.1%), high sensitivity (limit of detection in the range of 0.01–0.76 μg/kg), and good recoveries (83.21–105.34%) were obtained. With distinct advantages of simplicity, reliability and minimal sample requirement, the proposed mini-SPE procedure coupled with ultrahigh performance liquid chromatography and quadrupole time-of-flight tandem mass spectrometry could become an alternative tool to analyze the residues of MACs in complex food matrixes.
•The proposed molecular sieve was coupled with miniaturized SPE procedure.•An effective UHPLC-Q-TOF/MS method for analysis of flavanones had been presented.•The method was developed for the ...determination of complex citrus fruit samples.•Good precision, selectivity and sensitivity are observed.
An analytical procedure based on miniaturized solid phase extraction (SPE) and ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was developed and validated for determination of six flavanones in Citrus fruits. The mesoporous molecular sieve SBA-15 as a solid sorbent was characterised by Fourier transform-infrared spectroscopy and scanning electron microscopy. Additionally, compared with reported extraction techniques, the mesoporous SBA-15 based SPE method possessed the advantages of shorter analysis time and higher sensitivity. Furthermore, considering the different nature of the tested compounds, all of the parameters, including the SBA-15 amount, solution pH, elution solvent, and the sorbent type, were investigated in detail. Under the optimum condition, the instrumental detection and quantitation limits calculated were less than 4.26 and 14.29ngmL−1, respectively. The recoveries obtained for all the analytes were ranging from 89.22% to 103.46%. The experimental results suggested that SBA-15 was a promising material for the purification and enrichment of target flavanones from complex citrus fruit samples.
•UAE-DMSPE extraction using ILs and CSNPs was developed for enrichment of pigments.•The proposed method involves the use of UHPLC coupled with UV and Q-TOF/MS.•Different parameters affecting the ...extraction efficiency were optimized.•The method was applied to a determination of turmeric and rhubarb samples.
A green and economical method for the extraction and preconcentration of natural pigments (curcumin, demethoxycurcumin and bisdemethoxycurcumin) was developed using ultrasound-assisted extraction combined with dispersive micro solid-phase extraction. In this work, Ionic liquids (ILs) were used for the pre-extraction of natural pigments. The pure chitosan nanoparticles (CS NPs) were then used as a sorbent for the microextraction mode. The method involves the use of ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Operating parameters influencing the performance of extraction steps such as type and concentration of ILs, concentration of CS NPs, type of elution solvent, agitation time and pH of sample-extracting solution were investigated. Under the optimum conditions, the proposed method exhibited a low detection limit in the range of 0.11–0.36ng/mL at S/N=3, and good linearities with coefficients of determination (R2) higher than 0.9990. The recoveries of turmeric samples were ranging from 90.45% to 105.04% for the three studied curcuminoids with SD of 3.27–6.58. The experimental results indicated that the ILs and CS NPs were the promising materials for the extraction and enrichment of target curcuminoids from complex solid samples.
•The UAME and MAME were established for extraction of zingiberone, shogaol and gingerols from gingers.•Bile salts were applied as the extraction medium in the micellar extraction.•The proposed method ...involved the use of UHPLC-UV.•High extraction efficiencies of active compounds in gingers were achieved.•The proposed method was a rapid, simple, effective and environmentally friendly approach.
Two kinds of extraction methods ultrasonic-assisted micellar extraction (UAME) and microwave-assisted micellar extraction (MAME) coupled with ultra-high performance liquid chromatography with ultraviolet detector (UHPLC-UV) were developed and evaluated for extraction and determination of zingerone, 6-gingerol, 8-gingerol, 6-shogaol and 10-gingerol in Rhizoma Zingiberis and Rhizoma Zingiberis Preparata. A biosurfactant, hyodeoxycholic acid sodium salt, was used in micellar extraction. Several experimental parameters were studied separately by a univariate method. The result indicated that the MAME was more efficient than UAME. The optimal conditions of MAME were as follows: 100mM of hyodeoxycholic acid sodium salt was used as surfactant, the irradiation time was set at 10s and the extraction temperature was set at 60°C. The validation results indicated that the limits of detection were in the range of 3.80-8.11ng/mL. The average recoveries were in the range of 87.32-103.12% for the two samples at two spiking levels. Compared with other reported methods, the proposed MAME-UHPLC-UV method was more effective, quicker (10s) and more eco-friendly.
•The crown ether modified MWCNTs is prepared as sorbent in DMSPE procedure.•The method is established to preconcentrate the sudan dyes and their metabolites.•The proposed method involves the use of ...UHPLC-Q-TOF/MS.•High enrichment factors of target compounds are achieved.•The proposed method is a simple, time-saving, effective and eco-friendly approach.
In this study, dispersive micro solid phase extraction (DMSPE) combined with ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry method was established to extract and determine sudan dyes and their metabolites in real samples. The crown ether microfunctionalized multi-walled carbon nanotubes (MWCNTs) was applied as the sorbent in DMSPE procedure. Several experimental parameters that can effect the extraction performance of the DMSPE method were investigated separately by a univariate method. The validation data showed that the limits of detection were in the range of 0.084–13.13 μg/kg, the mean recoveries were ranged from 80.15 to 103.58% for six samples. Compared with other published methods, the proposed method was more effective, more time-saving and more eco-friendly. Finally, the developed method was successfully applied to enrich and detect sudan dyes and their metabolites in real samples.
•A novel and green cyclodextrin-assisted liquid-solid extraction method is presented.•The proposed method involves the use of UHPLC-ECD and Q-TOF/MS.•The innovative method was efficient and economic ...for phenolic compounds extraction.•This method was applied for the determination of phenolic compounds in jujube fruit samples.
A novel, simple and environmental friendly sample preparation technique based on the use of cyclodextrin has been developed for the extraction of phenolic compounds from jujube samples, the analytes being finally determined by ultrahigh performance liquid chromatography with electrochemical detection. Quadrupole time-of-flight tandem mass spectrometry was used to characterize the composition of jujube fruit. The present method exhibited higher efficiency for extracting phenolic compositions than Pharmacopoeia heat-reflux approach in term of peak areas. Moreover, compared with traditional ultrasound-assisted extraction, the developed methodology was found without the use of toxic organic solvent, meeting the principles of green chemistry. Validation experiments showed that the proposed method presented good linearity (r2>0.9970), satisfactory precision (RSD<7.55%), and high recovery (85.63–105.67%). The limits of detection were from 4.92ng/mL to 142.85ng/mL for eight phenolic compounds. Eventually, the optimized approach was successfully applied to the analysis of jujube fruit.
Aims
To retrospectively evaluate coronary anomalies and coronary wall atheromatous changes by using dual‐source computed tomography angiography (DSCTA) for preoperative assessment of patients with ...thoraco‐abdominal and noncoronary cardiovascular disease.
Materials and Methods
One hundred and eighty‐one patients scheduled for elective noncoronary cardiovascular surgery (heart valve disease group, HVD; arrhythmia group, Arrhy; or aortic aneurysm group, AA) underwent a DSCTA examination for preoperative preparation. Anomalous origin of coronary arteries, myocardial bridge (MB), coronary wall atheromatous changes, luminal stenosis, and types of plaques were evaluated and compared among the three groups.
Results
Anomalous origin of coronary arteries and MB were observed in 5.1% and 21.5% of patients. Anomalous origin of the coronary artery from the opposite sinus was most common (55.6%). MB was most frequently detected in the distal segment of the left anterior descending artery (LAD) (1.2%). Plaques were most common in the proximal segment of the LAD (16.4%) and LAD branches (42.2%). Diseased vessels and segments were more common in AA group, followed by Arrhy patients and finally HVD groups (p < 0.001 for each group). Multivessel involvement and significant stenosis of AA group were significantly more common than the other two groups. Noncalcified plaque and all grades of stenosis were more common in AA patients.
Conclusion
DSCTA is useful for preoperative assessment of coronary arteries in patients undergoing thoraco‐abdominal and noncoronary cardiovascular surgery. DSCTA detected higher prevalence of coronary artery disease in AA patients than in the other two groups of patients. doi: 10.1111/jocs.12244 (J Card Surg 2014;29:59‐65)
Coronary artery disease (CAD) is a common and severe complication of type 2 diabetes mellitus (DM). The aim of this study is to identify the features of CAD in diabetic patients using coronary CT ...angiography (CTA).
From 1 July 2009 to 20 March 2010, 113 consecutive patients (70 men, 43 women; mean age, 68 ± 10 years) with type 2 DM were found to have coronary plaques on coronary CTA. Their CTA data were reviewed, and extent, distribution and types of plaques and luminal narrowing were evaluated and compared between different sexes.
In total, 287 coronary vessels (2.5 ± 1.1 per patient) and 470 segments (4.2 ± 2.8 per patient) were found to have plaques, respectively. Multi-vessel disease was more common than single vessel disease (p < 0.001), and the left anterior descending (LAD) artery (35.8%) and its proximal segment (19.1%) were most frequently involved (all p < 0.001). Calcified plaques (48.8%) were the most common type (p < 0.001) followed by mixed plaques (38.1%). Regarding the different degrees of stenosis, mild narrowing (36.9%) was most common (p < 0.001); however, a significant difference was not observed between non-obstructive and obstructive stenosis (50.4% vs. 49.6%, p = 0.855). Extent of CAD, types of plaques and luminal narrowing were not significantly different between male and female diabetic patients.
Coronary CTA depicted a high plaque burden in patients with type 2 DM. Plaques, which were mainly calcified, were more frequently detected in the proximal segment of the LAD artery, and increased attention should be paid to the significant prevalence of obstructive stenosis. In addition, DM reduced the sex differential in CT findings of CAD.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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