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Hybrid perovskites have attracted enormous attention in the next generation resistive switching (RS) memristor for the artificial synapses, owing to their ambipolar charge transport, long diffusion length, and tunable visible bandgap. However, the variable switch, limited reproducibility, and poor endurance are the obstacles to the practical application of the perovskite memristors. Herein, we reported a multilevel RS nonvolatile memory based on a 3D trigonal HC(NH2)2PbI3 (α‐FAPbI3) perovskite layer modified by 1‐cyanobutyl‐3‐methylimidazolium chloride ([CNBmim]Cl) and sandwiched between ITO and Au electrodes (Au/[CNBmim]Cl/α‐FAPbI3/SnO2/ITO). In contrast to the bare memristor with failure switching from low resistance state (LRS) to high resistance state (HRS), the memristor device based on the α‐FAPbI3 modified with [CNBmim]Cl (Target device) shows the retention time over 104 s with On/Off ratio (>102) and endurance up to 550 cycles. The stable RS cycle benefits from the accelerated electrons de‐trapping from the reduced defects and fast charge separation in the interface of α‐FAPbI3/electrode, leading to the rupture of conductive filaments and transition of LRS to HRS. As a two‐terminal analog synaptic device, the target device can realize random handwritten digit recognition with an impressive accuracy of 89.3% on the condition of low learning phases (500 training cycles). [ABSTRACT FROM AUTHOR]

Objective: In clinical practice, noncontinuous two‐segment spinal cord cervical spondylosis is a particular form of cervical degenerative disease. Traditional anterior open surgery frequently comes with severe trauma, risks, and debatable treatment options. This study aimed to describe for the first time a novel minimally invasive technique, namely, anterior full‐endoscopic single‐port double transcorporeal spinal cord decompression for the treatment of patients with noncontinuous two‐segment cervical spondylotic myelopathy. Method: From February 2020 to May 2021, five patients with noncontinuous two‐segment cervical spondylotic myelopathy were treated with anterior full‐endoscopic single‐port double transcorporeal spinal cord decompression. Two bone channels were established by the trephine through the vertebral body oblique upward and downward to the herniated disc osteophyte complex, and the full‐endoscopic system could decompress the spinal cord through the channels. All cases were followed up for over 2 years. The modified Japanese Orthopaedic Association (mJOA) score and visual analogue scale (VAS) score before and after operation and during follow‐up were used to evaluate the clinical effectiveness. Radiological examinations, including CT and MRI, were utilized to evaluate the efficacy of spinal cord decompression and bone channel repair. Results: All operations were successfully completed and the average operation time was 185 min, with no operation‐related complications. Compared with the preoperative evaluation, the mJOA score and VAS score were improved at each time point after operation and follow‐up. Postoperative CT and MRI scans showed that the intervertebral disc‐osteophyte complex was removed through the vertebral bone passage, and the spinal cord was fully decompressed. After 24 months of follow‐up, CT and MRI scans showed that the bone channel was almost repaired and healed. Conclusion: Anterior full‐endoscopic single‐port double transcorporeal spinal cord decompression is an effective minimally invasive technique for noncontinuous two‐segment cervical spondylosis. It provides precise and satisfactory spinal cord decompression under endoscopic visualization with minimum trauma. [ABSTRACT FROM AUTHOR]

Mycotoxin contamination is widespread in plants and herbs, posing serious threats to the consumer and human health. Of them, alternariol (AOH) has attracted great attention as an "emerging" mycotoxin in medicinal herbs. However, a specific and high‐throughput extraction method for AOH is currently lacking. Thus, developing an efficient pre‐treatment technique for AOH detection is extremely vital. Here, a novel automated magnetic solid‐phase extraction method was proposed for the highly efficient extraction of AOH. Combining the aptamer‐functionalized magnetic nanoparticles (AMNPs) and the automatic purification instrument, AOH could be extracted in medicinal herbs in high throughput (20 samples) and a short time (30 min). The main parameters affecting extraction were optimized, and the method was finally carried out by incubation AMNPs with 3 mL of sample solution for 10 min, and then desorption in 75% methanol for liquid‐phase detection. Under optimal conditions, good reproducibility, stability, and selectivity were realized with an adsorption capacity of 550.84 ng/mg. AOH extraction in three edible herbs showed good resistance to matrix interference with recovery rates from 86% to 111%. In combination with AMNPs and the automatic purification instrument, high‐throughput and labor‐free extraction of AOH in different complex matrices was achieved, which could be extended in other complex matrices. [ABSTRACT FROM AUTHOR]

Mycotoxin contamination in foods has posed serious threat to public health and raised worldwide concern. The development of simple, rapid, facile, and cost‐effective methods for mycotoxin detection is of urgent need. Aptamer‐based sensors, abbreviated as aptasensors, with excellent recognition capacity to a wide variety of mycotoxins have attracted ever‐increasing interest of researchers because of their simple fabrication, rapid response, high sensitivity, low cost, and easy adaptability for in situ measurement. The past few decades have witnessed the rapid advances of aptasensors for mycotoxin detection in foods. Therefore, this review first summarizes the reported aptamer sequences specific for mycotoxins. Then, the recent 5‐year advancements in various newly developed aptasensors, which, according to the signal output mode, are divided into electrochemical, optical and photoelectrochemical categories, for mycotoxin detection are comprehensively discussed. A special attention is taken on their strengths and limitations in real‐world application. Finally, the current challenges and future perspectives for developing novel highly reliable aptasensors for mycotoxin detection are highlighted, which is expected to provide powerful references for their thorough research and extended applications. Owing to their unique advantages, aptasensors display a fascinating prospect in food field for safety inspection and risk assessment. [ABSTRACT FROM AUTHOR]

Rapid, economic, and highly effective determination of multiple mycotoxins in complex matrices has given huge challenges for the analytical method. In this study, an economic analytical strategy based on sensitive and rapid ultrafast liquid chromatography coupled to hybrid triple quadrupole/linear ion trap mass spectrometry technique was developed for the determination of seven mycotoxins of different chemical classes (aflatoxin B1, B2, G1, and G2, ochratoxin A, T‐2 toxin, and HT‐2 toxin) in Polygonum multiflorum. Target mycotoxins were completely extracted using a modified quick, easy, cheap effective, rugged, and safe method without additional clean‐up steps. The types of extraction solvents and adsorbents for the extraction procedure were optimized to achieve high recoveries and reduce coextractives in the final extracts. Due to significant matrix effects for all analytes (≤68.9% and ≥110.0%), matrix‐matched calibration curves were introduced for reliable quantification, exploring excellent linearity for the seven mycotoxins with coefficients of determination >0.9992. The method allowed high sensitivity with limit of detection in the range of 0.031–2.5 μg/kg and limit of quantitation in the range of 0.078–6.25 μg/kg, as well as satisfactory precision with relative standard deviations lower than 8%. Recovery rates were between 74.3 and 119.8% with relative standard deviations below 7.43%. The proposed method was successfully applied for 24 batches of P. multiflorum samples, and six samples were found to be positive with aflatoxin B1, B2, G1, or ochratoxin A. The method with significant advantages, including minimum analytical time, low time and solvent consumption, and high sensitivity, would be a preferred candidate for economic analysis of multiclass mycotoxins in complex matrices. [ABSTRACT FROM AUTHOR]

Objective. To observe the clinical curative effect of posterior total endoscopic precision decompression for the treatment of single-segment lateral crypt lumbar spinal stenosis (LSS). Method. A total of 27 patients with single-segment LSS satisfying the inclusion criteria were recruited from July 2013 to September 2015. There were 18 cases of unilateral stenosis of the L4-5 segments and 9 cases of unilateral stenosis of the L5-S1 segment. All patients were treated via the posterior approach with the precise lateral crypt decompression technique. Precise decompression was performed on the narrow areas causing clinical symptoms. Clinical efficacy was assessed at 3 days, 3 months, 6 months, and 2 years after surgery. Low-back pain and sciatic nerve pain assessed by visual analog scale (VAS) score and the functional Oswestry Disability Index (ODI) were used to evaluate lumbar function, and modified MacNab score criteria were used to investigate long-term efficacy. Result. All patients completed the operation successfully, and the follow-up time was 2 years. The VAS score of lumbago was lower after than before surgery (preoperative: 6.96±0.90; postoperative: 2.04±1.02, P<0.05). The VAS score of sciatica was also lower after than before surgery (preoperative: 7.19±0.88, postoperative: 1.93±0.92, P<0.05), and the ODI was improved at the last follow-up (29.62±4.26) % compared with before surgery (80.07±3.98) %. The MacNab efficacy evaluation showed improvement at the end of the follow-up period: 20 cases were excellent, 6 cases were good, and 1 case was satisfactory, with a good/excellent rate of 96%. No surgical site infections, iatrogenic nerve root injuries, epidural hematomas, or other complications occurred. Conclusion. Total endoscopic decompression of posterior facet arthrodesis for the treatment of single-segment lateral crypt LSS has the advantages of safety, reduced recurrence and trauma, and a satisfactory curative effect. This trial is registered with ChiCTR1800015628. [ABSTRACT FROM AUTHOR]

The objective of this study is to introduce a method using a percutaneous full-endoscopic interlaminar approach via a surrounding nerve root discectomy (SNRD) operative route that involves removing the protrusive disc via both the shoulder and the axilla of the corresponding nerve root for the treatment of ventral-type lumbar disc herniation (VLDH) and its early clinical symptoms. Twenty-two patients with VLDH satisfied the inclusion criteria and underwent the full-endoscopic interlaminar approach operation via a SNRD successfully during the period from November 2014 to June 2016. All operations were completed without conversion to other surgical techniques. The average operation time was 78.64 ± 25.97 min (50–145 min). The average removed disc tissue volume was 2.87 ± 0.48 ml (2–3.6 ml). No nerve root injury, infection, or other complications occurred. The postoperative ODI and VAS values of low back and sciatic pain were significantly decreased at each time point compared to preoperative measurements P<0.05. The MacNab scores at the 12-month follow-up included 15 excellent and 7 good scores. In summary, a percutaneous full-endoscopic interlaminar approach through SNRD is a safe and effective treatment option for patients with VLDH. [ABSTRACT FROM AUTHOR]

The objective was to investigate the effective and safe range of paramedian CDH by percutaneous posterior full-endoscopy cervical intervertebral disc nucleus pulposus resection (PPFECD) to provide a reference for indications and patient selection. Sixteen patients with CDH satisfied the inclusion criteria. Before surgery the patients underwent cervical spine MRI, and the distance between the dural sac and herniated disc was measured. An assessment was performed by MRI immediately after surgery, measuring the distance between dural sac and medial border of discectomy (DSMD). The preoperative average distance between the dural sac and peak of the herniated disc (DSPHD) was 3.87 ± 1.32 mm; preoperative average distance between dural sac and medial border of herniated disc (DSMHD) was 6.91 ± 1.21 mm and an average distance of postoperative DSMD was 5.41 ± 1.40 mm. Postoperative VAS of neck and shoulder pain was significantly decreased but JOA was significantly increased in each time point compared with preoperative ones. In summary, the effective range of PPFECD to treat paramedian CDH was 5.41 ± 1.40 mm, indicating that DSMHD and DSPHD were within 6.91 ± 1.21 mm and 3.87 ± 1.32 mm, respectively. PPFECD surgery is, therefore, a safe and effective treatment option for patients with partial paramedian cervical disc herniation. [ABSTRACT FROM AUTHOR]

Morinda officinalis (Rubiaceae) is a traditional Chinese medicine widely used for the treatment of impotence and osteoporosis in clinical therapy. In the present study, a rapid and simple ultra-high performance liquid chromatography with photodiode array detection method was developed and validated for the simultaneous determination of 11 bioactive compounds in M. officinalis. This assay method was validated with respect to linearity ( R2 > 0.9991), precision, repeatability, limit of detection, limit of quantification, and accuracy (with observed recovery rates between 94.21 and 100.38%). The quantitative results revealed significant differences in the concentrations of the selected compounds. Additionally, chemometric methods, including hierarchical clustering analysis, principal component analysis, and partial least-squares discriminate analysis, were applied to compare and sort the 25 batches of M. officinalis samples based on the quantitative data of the analytes. All of the samples were clearly divided into two groups: the Hainan samples were successfully discriminated from the samples from other origins. Simultaneous determination of multiple compounds using the proposed method combined with chemometrics could be a viable strategy to compare and evaluate the quality of M. officinalis. [ABSTRACT FROM AUTHOR]

Atractylodes rhizome is a valuable traditional Chinese medicinal herb that comprises complex several species whose essential oils are the primary pharmacologically active component. Essential oils of Atractylodes lancea and Atractylodes koreana were extracted by hydrodistillation, and the yield was determined. The average yield of essential oil obtained from A. lancea (2.91%) was higher than that from A. koreana (2.42%). The volatile components of the essential oils were then identified by a gas chromatography with mass spectrometry method that demonstrated good precision. The method showed clear differences in the numbers and contents of volatile components between the two species. 41 and 45 volatile components were identified in A. lancea and A. koreana, respectively. Atractylon (48.68%) was the primary volatile component in A. lancea, while eudesma-4(14)-en-11-ol (11.81%) was major in A. koreana. However, the most significant difference between A. lancea and A. koreana was the major component of atractylon and atractydin. Principal component analysis was utilized to reveal the correlation between volatile components and species, and the analysis was used to successfully discriminate between A. lancea and A. koreana samples. These results suggest that different species of Atractylodes rhizome may yield essential oils that differ significantly in content and composition. [ABSTRACT FROM AUTHOR]

BACKGROUND Aflatoxins ( AFs) and ochratoxin A ( OTA) have been detected frequently in food, agricultural products and traditional Chinese medicines, and their presence poses serious health and economic problems worldwide. Ginger can easily be polluted with mycotoxins. In this study, ginger samples were cultivated for 15 days after inoculation with fungi and were prepared based on ultrasound-assisted solid-liquid extraction using methanol/water followed by immunoaffinity column clean-up and analysed by ultra-fast liquid chromatography-tandem mass spectrometry ( UFLC-MS/ MS) for AFs and OTA. RESULTS The limits of detection and quantification of AFs and OTA were 0.04-0.30 µg mL−1 and 0.125-1.0 µg mL−1, respectively. The recoveries were 82.0-100.2%. After 15 days' cultivation, no macroscopic mildew was found in ginger. But, the content of AFB1 expressed an increasing trend in ginger, peel [less than the limit of quantification ( LOQ)] to the innermost layer (51.86 µ mL−1 ), AFB2 was only detected in the innermost layer at the level of 0.87 µ mL−1. A small amount (< LOQ) of OTA was found in the peel of ginger after the two fungi were inoculated on the surface of ginger. CONCLUSION The developed method was successfully applied to analyse five mycotoxins, and has many advantages including rapid determination and high sensitivity. Meanwhile, in practice, more attention should be paid to the safety and quality of ginger. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Objective is to analyze the surgical strategy, safety, and clinical results of percutaneous full-endoscopic discectomy through interlaminar or extraforaminal puncture technique for LDH. Preoperative CT and MRI were analyzed, which were based on the main location of the herniated disc and its relationship with compressed nerve root. Sixty-two patients satisfied the inclusion criteria during the period from August 2012 to March 2014. We use percutaneous full-endoscopic discectomy through different puncture technique to remove the protrusive NP for LDH. Sixty patients completed the full-endoscopic operation successfully. Their removed disc tissue volume ranged from 1.5 mL to 3.8 mL each time. Postoperative ODI and VAS of low back and sciatica pain were significantly decreased in each time point compared to preoperative ones. No nerve root injury, infection, and other complications occurred. The other two patients were shifted to open surgery. No secondary surgery was required and 91.6% of excellent-to-good ratio was achieved on the basis of Macnab criteria at postoperative 12 months. Acquired benefits are fewer complications, rapid recovery, complete NP removal, effective nerve root decompression, and satisfactory cosmetic effect as well. This is a safe, effective, and rational minimally invasive spine-surgical technology with excellent clinical outcome. [ABSTRACT FROM AUTHOR]

This study assessed the feasibility of gas chromatography with flame ionization detection fingerprinting combined with chemometrics for quality analysis of Atractylodes rhizome. We extracted essential oils from 20 Atractylodes lancea and Atractylodes koreana samples by hydrodistillation. The variation in extraction yields (1.33-4.06%) suggested that contents of the essential oils differed between species. The volatile components (atractylon, atractydin, and atractylenolide I, II, and III) were quantified by gas chromatography with flame ionization detection and confirmed by gas chromatography with mass spectrometry, and the results demonstrated that the number and content of volatile components differed between A. lancea and A. koreana. We then calculated the relative peak areas of common components and similarities of samples by comparing the chromatograms of A. lancea and A. koreana extracts. Also, we employed several chemometric techniques, including similarity analysis, hierarchical clustering analysis, principal component analysis, and partial least-squares discriminate analysis, to analyze the samples. Results were consistent across analytical methods and showed that samples could be separated according to species. Five volatile components in the essential oils were quantified to further validate the results of the multivariate statistical analysis. The method is simple, stable, accurate, and reproducible. Our results provide a foundation for quality control analysis of A. lancea and A. koreana. [ABSTRACT FROM AUTHOR]

BACKGROUND Although increasing attention has been paid to the health threat caused by mycotoxins in commodities such as food or medicines, mycotoxin transfer processes from crude material to products have raised little concern so far. Radix Astragali is a commonly used edible and medicinal herbal plant that is susceptible to contamination with aflatoxins from Aspergillus flavus. There have been no studies on mycotoxin transfer into pharmaceutical preparations or derivative products. RESULTS To facilitate the aflatoxin reduction and bioactivity retention, the dynamic variations of aflatoxins as well as herbal compounds, namely calycosin-7-glucoside, astragaloside and formononetin, in Radix Astragali contaminated by A. flavus during water decoction and ethanol refluxing treatments were evaluated simultaneously by an ultra-fast liquid chromatography-triple quadrupole linear ion trap mass spectrometry method. After the extraction processes, although the amount of alfatoxins was reduced remarkably, aflatoxin residuals in preparation still exceed recommended limits, manifesting the great need to establish a limit for aflatoxins in herbal extractions or derivative products. Meanwhile, due to the hydrolysis of glucoside, water decoction period should be no longer than 4 h. CONCLUSIONS This investigation would benefit from the determination of the dynamic variation of aflatoxins in infected herbs in preparation treatments, in order to further develop aflatoxin limits in herbal preparations. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

An ultra high performance liquid chromatography with photodiode array detection method is developed for the simultaneous quantitative determination of five water-soluble compounds including danshensu, protocatechualdehyde, rosmarinic acid, salvianolic acid B, and salvianolic acid A in Salvia miltiorrhiza Bge. samples. Through method optimization, the five compounds all expressed good linearity ( R2 > 0.9990) in a wide concentration range together with satisfactory accuracy, precision, and stability. Moreover, through qualitative analysis of the chemical fingerprint combined with similarity analysis, hierarchical cluster analysis, principle component analysis, and partial least-squares discriminate analysis, we determined that the 13 batches of Salvia miltiorrhiza Bge. were similar in internal quality and the differences resulted from various cultivation environments, recovery elements, and others. Seen from the results of hierarchical cluster analysis and principle component analysis, the classification of 13 batches was in accordance, and partial least-squares discriminate analysis technique was more suitable than the principle component analysis model to provide a distinct classification of test samples on the basis of their different components. Moreover, a permutation test verified the rationality of partial least-squares discriminate analysis and variable importance plot showed that peaks 37 and 38 were the most significant variables in distinguishing the Salvia miltiorrhiza Bge. samples. The idea of the quantitative and qualitative analysis of Salvia miltiorrhiza Bge. was convenient, sensitive, and comprehensive, which could be applied to evaluate the quality of more traditional Chinese medicines. [ABSTRACT FROM AUTHOR]

A rapid, selective, and sensitive ultra-fast liquid chromatography with tandem mass spectrometry method was developed for the determination of ochratoxin A in traditional Chinese medicines based on vortex-assisted solid-liquid microextraction and aptamer-affinity column clean-up. Through optimizing the sample pretreatment procedures and chromatographic conditions, good linearity ( r2 ≥ 0.9993), low limit of detection (0.5-0.8 μg/kg), and satisfactory recovery (83.54-94.44%) expressed the good reliability and applicability of the established method in various traditional Chinese medicines. Moreover, the aptamer-affinity column, prepared in-house, showed an excellent feasibility owing to its specific identification of ochratoxin A in various kinds of selected traditional Chinese medicines. The maximum adsorption amount and applicability value were 188.96 ± 10.56 ng and 72.3%, respectively. The matrix effects were effectively eliminated, especially for m/z 404.2→358.0 of ochratoxin A. The application of the developed method for screening the natural contamination levels of ochratoxin A in 25 random traditional Chinese medicines on the market in China indicated that only eight samples were contaminated with low levels below the legal limit (5.0 μg/kg) set by the European Union. This study provided a preferred choice for the rapid and accurate monitoring of ochratoxin A in complex matrices. [ABSTRACT FROM AUTHOR]

A simple, reliable, and highly sensitive method for the simultaneous determination of aflatoxin B1, B2, G1, G2 in Fructus Bruceae was developed using high-performance liquid chromatography coupled to online postcolumn photochemical derivatization and fluorescence detection. Aflatoxins were first extracted by a methanol/water mixture and then cleaned up with an AflaTest™ immunoaffinity column. Different clean-up and derivatization methods were compared and optimized. The established method was extensively validated to show satisfactory performance of linearity ( R2 ≥ 0.9997), recovery (74.3-100.8%), and precision (RSDs ≤ 2.8%) for the investigated aflatoxins. This proposed method was also applied to 11 F. Bruceae samples and the results showed that 10 out of 11 were contaminated with aflatoxins ranging from 0.26 to 27.52 μg/kg and the occurrence of aflatoxin B1, the most toxic one, was as high as 91% in all the samples, highlighting the severe contamination and the necessity to set legal limits for aflatoxins in F. Bruceae. [ABSTRACT FROM AUTHOR]

Aptamers are single-stranded oligonucleotides with high affinity and specificity and are widely used in targets separation and enrichment. Here, an aptamer-affinity column (AAC) was firstly prepared in-house through a covalent immobilization strategy. Then, ochratoxin A (OTA) in ginger powder was absorbed and enriched using the new aptamer-based clean-up technology for the first time, and was further analyzed by ultra high performance liquid chromatography with fluorescence detection. After optimization, the average recoveries for blank samples spiked with OTA at 5, 15, and 45 μg/kg ranged from 85.36 to 96.83%. Furthermore, the AAC exhibited a similar accuracy as an immunoaffinity column to clean up OTA in ginger powder. Above all, it exhibited better reusability, twice that of the immunoaffinity column, had lower toxicity and cost, and took less time. Of 25 contaminated ginger powder samples, OTA contamination levels ranged from 1.51 to 4.31 μg/kg, which were lower than the European Union (EU) regulatory limits. All the positive samples were further confirmed by ultra-fast LC with MS/MS. In conclusion, the method of clean-up based on the AAC coupled to ultra-HPLC with fluorescence detection was rapid, specific, and sensitive for the quantitative analysis of OTA in a complex matrix. [ABSTRACT FROM AUTHOR]

Curcumae longae rhizome is a widely used traditional herb in many countries. Various geographical origins of this herb might lead to diversity or instability of the herbal quality. The objective of this work was to establish the chemical fingerprints for quality control and find the chemical markers for discriminating these herbs from different origins. First, chemical fingerprints of essential oil of 24 C. longae rhizome from four different geographical origins in China were determined by GC- MS. Then, pattern recognition techniques were introduced to analyze these abundant chemical data in depth; hierarchical cluster analysis was used to sort samples into groups by measuring their similarities, and principal component analysis and partial least-squares discriminate analysis were applied to find the main chemical markers for discriminating these samples. Curcumae longae rhizome from Guangxi province had the highest essential oil yield (4.32 ± 1.45%). A total of 46 volatile compounds were identified in total. Consistent results were obtained to show that C. longae rhizome samples could be successfully grouped according to their origins, and turmerone, ar-turmerone, and zingiberene were the characteristic components for discriminating these samples of various geographical origins and for quality control. This finding revealed that fingerprinting analysis based on GC- MS coupled with chemometric techniques could provide a reliable platform to discriminate herbs from different origins, which is a benefit for quality control. [ABSTRACT FROM AUTHOR]

Ginger, a widely used spice and traditional Chinese medicine, is prone to be contaminated by mycotoxins. A simple, sensitive, and reproducible method based on immunoaffinity column clean-up coupled with HPLC and on-line postcolumn photochemical derivatization with fluorescence detection was developed for the simultaneous determination of aflatoxins ( AFs) B1, B2, G1, G2, and ochratoxin A ( OTA) in 25 batches of gingers and related products marketed in China for the first time. The samples were first extracted by ultrasonication with methanol/water (80:20, v/v) and then cleaned up with immunoaffinity columns for analysis. Under the optimized conditions, the LODs and LOQs for the five mycotoxins were 0.03-0.3 and 0.1-0.9 μg/kg, respectively. The average recoveries ranged from 81.3-100.8% for AFs and from 88.6-99.5% for OTA at three spiking levels. Good linearity was observed for the analytes with correlation coefficients all >0.9995. All moldy gingers were contaminated with at least one kind of the five investigated mycotoxins, while none of them were found in normal gingers. Ginger powder samples were contaminated slightly with the contamination levels below the LOQs, while ginger tea bags were mainly contaminated by OTA at 1.05-1.19 μg/kg and ginger black tea bags were mainly contaminated by AFs at 3.37-5.76 μg/kg. All the contamination levels were below the legally allowable limits. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction Glycyrrhizae species are popular ingredients of herbal medicine in most traditional Chinese medicine prescriptions, and they mainly contain flavonoids and triterpene saponins. The contents of these bioactive compounds may vary in different batches and affect the therapeutic effects. Thus comprehensive quality control and monitoring of their herbal formulation are of paramount concern. Objective To establish a rapid, effective pressurised liquid extraction (PLE) and ultra-performance liquid chromatography coupled with photodiode array (UPLC-PDA) method to evaluate the quality of Glycyrrhizae species. Methods Radix Glycyrrhizae was extracted by PLE using 70% ethanol at 100°C for 15 min during three static extraction cycles. Separation was performed using an UPLC system to quantify five bioactive compounds, namely liquiritin apioside, liquiritin, liquiritigenin, glycyrrhizic acid and glycyrrhetinic acid, in 12 batches of samples of different origins in China. Furthermore, the samples were analysed using an ultra-performance liquid chromatography coupled with electrospray ionisation and time-of-flight mass spectrometry (UPLC/ESI-QTOF-MS) system to confirm the results. Results The calibration curves of all five analytes showed good linearity ( R2 > 0.9997). Accuracy, precision and repeatability were all within required limits. The mean recoveries measured at the three concentrations were higher than 93.7% with RSDs lower than < 3.33% for the targets. Conclusion The established PLE and UPLC-PDA method could serve as a rapid and effective method for quality evaluation of Radix Glycyrrhizae. The UPLC technique can be considered as an attractive alternative to HPLC in routine quality control of Chinese medicine, especially in situations where high sample throughput and fast analytical speed are required. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Sample preparation is always the major bottleneck in analytical chemistry for the determination of pesticide residues. Different sample preparation methods have been proposed due to the wide variety of pesticides used and the inherent complexity of the matrices. In this study, different sample preparation methods including SPE, matrix solid-phase dispersion, the quick, easy, cheap, efficient, rugged, and safe method, and a one-step completion method were compared and evaluated for extracting pesticides from lotus seeds. Analysis was carried out using GC with electron-capture detection. The results showed that good recoveries for tested pesticides were obtained by using Florisil in the four methods, and the extraction efficiency of the one-step completion method was superior to the other three methods. The one-step completion method was confirmed to have good linearity, reproducibility, stability, and recovery for the detection of 36 pesticides in lotus seed samples. The data collected from this study are expected to prove useful in regulating the concentration of the residues in lotus seeds, as well as in protecting human health from the hazards posed by these residues. [ABSTRACT FROM AUTHOR]

A simple, reliable, and low-cost method based on molecularly imprinted polymer as a selective sorbent of SPE was proposed for the determination of ochratoxin A ( OTA) in beer, red wine, and grape juice by HPLC coupled with fluorescence detection ( HPLC- FLD). Samples were diluted with water and cleaned up with an AFFINIMIP® SPE OTA column. After washing and eluting, the analyte was analyzed by HPLC- FLD. Under the optimized conditions, LOD and LOQ for OTA were 0.025 and 0.08 ng/mL, respectively. The recoveries of OTA from beer, red wine, and grape spiked at 0.1, 2, and 5 ng/mL ranged from 91.6 to 101.7%. Furthermore, after a simple regenerated procedure, the molecularly imprinted polymer based SPE column could be reused at least 14 times to achieve more than 80% recoveries of OTA in real samples. The developed method was applied to the detection of 30 beer, red wine, and grape juice samples and only four samples were contaminated by OTA with levels below the legal limits. [ABSTRACT FROM AUTHOR]

A simple and sensitive HPLC coupled with photodiode array ( HPLC-PDA) method was developed for simultaneous determination of seven lignans in Justicia procumbens using relative response factors ( RRFs). The chromatographic separation was performed on a Shiseido Capcell Pak C18 column (250 × 4.6 mm id, 5 μm), a gradient elution of acetonitrile/water, and a photodiode array detector. The column temperature was maintained at 35° C and the detection wavelength was set at 256 nm. Chinensinaphthol methyl ether was selected as the reference compound for calculating the relative response factors of the lignans. It has shown that the RRFs for lignans are quite similar at 256 nm of detection under different analytical conditions (different columns and HPLC instruments). Using RRFs, not every lignan is needed as a reference standard, making the method ideal for rapid, routine analysis, especially for those laboratories where lignans standards are not readily available. An economic and practicable HPLC method using RRFs was established for the determination of seven lignans in J. procumbens. This method not only can determine multiple indexes in traditional Chinese medicines (TCMs) simultaneously, but also resolve the problem of lacking of chemical standards. It will be a good quality evaluation method and pattern for TCMs. [ABSTRACT FROM AUTHOR]

A new solid-phase extraction ( SPE) pretreatment method using a home-made polyvinylpolypyrrolidone-florisil ( PVPP- F) column was developed for the analysis of patulin in apple and hawthorn products in China. Fifty samples (25 apple juices, 12 apple jams, and 13 hawthorn juices) were prepared using the new method and then analyzed by high performance liquid chromatography with diode array detection ( HPLC- DAD) on an Agela Venusil MP C18 reversed-phase column (4.6 mm × 250 mm, 5 μm). The cleanup results for all samples using home-made PVPP- F column were compared with those obtained using a Myco Sep®228 Afla Pat column. The correlation coefficient R (0.9998) fulfilled the requirement of linearity for patulin in the concentration range of 2.5-250 μg/kg. The limits of detection ( LODs) and quantification ( LOQs) of patulin were 3.99 and 9.64 μg/kg for PVPP- F column, and 3.56 and 8.07 μg/kg for Myco Sep®228 Afla Pat column, respectively. Samples were spiked with patulin at levels ranging from 25 to 250 μg/kg, and recoveries using PVPP- F and Myco Sep®228 Afla Pat columns were in the range of 81.9-100.9% and 86.4-103.9%, respectively. Naturally occurring patulin was found in 2 of 25 apple juice samples (8.0%) and 1 of 13 hawthorn juice samples (7.7%) at concentrations ranging from 12.26 to 36.81 μg/kg. The positive results were further confirmed by liquid chromatography electrospray ionization mass spectrometry ( LC- ESI- MS). [ABSTRACT FROM AUTHOR]

A rapid, simple and sensitive ultra high-performance liquid chromatography (UHPLC-MS/MS) method was established for determining the absorption amount of emodin in the five digestive segments of rat. Plasma samples were pre-purified by solid-phase extraction (SPE) with Oasis MAX cartridge. Separation of emodin and 1,8-dihydroxyanthraquinone (internal standard) was performed on an Acquity BEH UHPLC C column (100 mm×2.1 mm, 1.7 μm) with gradient elution of methanol and 0.1% formic acid aqueous solution. The LC/MS system was operated under multiple reaction monitoring mode using electrospray ionization (ESI) in negative ion mode. The results showed that this established method was valid and sensitive for emodin within 0.04-16.4 μg/mL, with low limits of detection and quantification of 0.6 ng/mL and 2.4 ng/mL, respectively and upper limit of quantification of 220.0 ng/mL. The intra- and interday variations were below 4.9% of RSD. The extraction recoveries were 98.9-106.1% with RSD of 1.9-3.2%. The plasma concentration-time relationship showed that the absorption of emodin in stomach was faster than in intestine segments. The sequence of absorption amount was: ileum>jejunum>colon≈duodenum>stomach. Most of emodin was absorbed in ileum, and the absorption amount was increased with prolonged retention of drug form in intestine, especially in ileum and jejunum. The developed UHPLC-ESI-MS/MS method was appropriate for determining the in vivo absorption of emodin in other herbal medicines or preparations containing this compound. [ABSTRACT FROM AUTHOR]