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Background Major depressive disorder (MDD) is a serious psychiatric disorder marked by low mood and anhedonia. Understanding the neural mechanism of MDD is essential for the treatment of depression. White matter fibres, connecting different computational units in the brain, have an important effect on brain function; however, the mechanism of white matter fibre abnormality in MDD is still unclear. Aims Our study expected to find white matter abnormalities associated with the frontal lobe and hippocampus in individuals with MDD. Method Using diffusion tensor imaging data and tract-based spatial statistics, we investigated the microstructural differences in white matter fibre tracts between 30 adults with MDD compared with 31 healthy controls, and calculated the association between MDD-related microstructural changes and illness duration. Results It was found that patients with MDD showed reduced fractional anisotropy in the genu and body of the corpus callosum, right corona radiata and part of the thalamic radiations, suggesting lower fibrous myelination levels in these regions; the decreased fractional anisotropy in these regions was associated with longer illness duration. Conclusions Our results suggest that MDD may be associated with microstructural damage of key fibre tracts, which could provide insights into the understanding and treatment of MDD.

Carbon dots (CDots) are defined as surface-passivated small carbon nanoparticles, with the effective passivation generally achieved by organic functionalization. Photoexcited CDots are both potent electron donors and acceptors, and their characteristic bright and colorful fluorescence emissions make them excellent fluorescence sensors for organic analytes and metal ions. For the latter extraordinarily low detection limits based on extremely efficient quenching of fluorescence intensities by the targeted metal cations have been observed and reported in the literature. However, all of the dot samples in those reported studies were made from “one-pot” carbonization of organic precursors mostly under rather mild processing conditions, unlikely to be sufficient for the required level of carbonization. Those dot samples should therefore be more appropriately considered as “nano-carbon/organic hybrids”, characterized structurally as being highly porous and spongy, which must be playing a dominating role in the reported sensing results. In this study, we compared the dot samples from carbonization syntheses under similarly mild and also more aggressive processing conditions with the classically defined and structured CDots for the fluorescence sensing of copper(II) cations in aqueous solutions. The observed dramatic decoupling between quenching results for fluorescence intensities and lifetimes of the carbonization samples, with the former being extraordinary and the latter within the diffusion controlled limit, suggested that the quenching of fluorescence intensities was greatly affected by the higher local quencher concentrations than the bulk associated with the porous and spongy sample structures, especially for the sample from carbonization under too mild processing conditions. The major differences between the classical CDots and the nano-carbon/organic hybrids are highlighted, and the tradeoffs between sensitivity and accuracy or reproducibility in the use of the latter for fluorescence sensing are discussed.

Natural products have provided numerous lead compounds for drug discovery. However, the traditional analytical methods cannot detect most of these active components, especially at their usual low concentrations, from complex natural products. Herein, we reviewed the recent technological advances (2015–2019) related to the separation and screening bioactive components from natural resources, especially the emerging screening methods based on the bioaffinity techniques, including biological chromatography, affinity electrophoresis, affinity mass spectroscopy, and the latest magnetic and optical methods. These screening methods are uniquely advanced compared to other traditional methods, and they can fish out the active components from complex natural products because of the affinity between target and components, without tedious separation works. Therefore, these new tools can reduce the time and cost of the drug discovery process and accelerate the development of more effective and better-targeted therapeutic agents., Graphical abstract This review summarizes the recent technological advances (2015–2019) related to the separation and screening bioactive components from natural resources, especially the emerging screening methods based on the bioaffinity techniques.Image 1

Cow's milk allergy is mainly observed in infants and young children. Most allergic reactions affect the skin, followed by the gastrointestinal and respiratory systems. Conventional diagnosis is based on positive allergy studies and evaluation of parameters including IgE and IgG1 levels, acute allergic skin response and anaphylactic shock reactions. We developed a cell membrane chromatographic (CMC) method based on human mast cells (HMC-1) for screening potential allergens in infant formula milk powders (IFMP). HMC-1 cell membranes were extracted and mixed with silica to prepare cell membrane chromatography columns (10 mm × 2 mm i.d., 5 µm). Under the conditions of 0.2 mL/min flow rate and 214 nm detection wavelength, human breast milk showed no retention. However, IFMP showed clear retention. The retained fractions were collected and analyzed through matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). Four major milk proteins, i.e., α-casein, β-casein, α-lactalbumin, and β-lactoglobulin A, were identified. Furthermore, these proteins and β-lactoglobulin B showed clear retention on HMC-1/CMC columns. To test the degranulation effects of the five proteins, histamine and β-hexosaminidase release assays were carried out. All five proteins induced HMC-1 cells to release histamine and β-hexosaminidase. Also, we established a reversed phase liquid chromatographic (RPLC) method for the determination of the five proteins in IFMP and the results showed that 90% proteins in IFMP were α-casein and β-casein. We concluded that cow's milk proteins may be potential allergens and caseins cause more β-casein allergic risk than other proteins. This conclusion was consistent with other studies. Keywords: Allergenic proteins, Cell membrane chromatography, Milk powders

Carthami flos, commonly known as Honghua in China, is the dried floret of safflower and widely acknowledged as a blood stasis promoting herb. The study aimed at investigating the relationship between thrombin and carthami flos through a high-performance thrombin affinity chromatography combined with a high-performance liquid chromatography-tandem mass spectrometry system. First, thrombin was immobilized on the glutaraldehyde-modified amino silica gel to prepare the thrombin affinity stationary phase, which was packed into a small column (1.0 × 2.0 mm, id) for recognizing the anticoagulant active components of carthami flos. The target component was enriched and analyzed by the high-performance liquid chromatography-tandem mass spectrometry system. Finally, hydroxysafflor yellow A was screened out and identified as the active component. The anticoagulant effects of hydroxysafflor yellow A were analyzed by anticoagulant experiments in vitro, and the interaction of hydroxysafflor yellow A with thrombin was investigated by the molecular docking method. The results proved that hydroxysafflor yellow A (30 μg/mL, 0.05 mM) and carthami flos extract (30 μg/mL) could prolong activated partial thrombin time and thrombin time by 50 and 11%, respectively. Moreover, hydroxysafflor yellow A exhibits a good hydrogen bond field and stereo field matching with thrombin. Overall, it was concluded that hydroxysafflor yellow A might exert an anticoagulation effect by interacting with thrombin and thus could be potential anticoagulant drugs for the prevention and treatment of venous thrombosis.

Carbon dots (CDots) are defined as surface-passivated small carbon nanoparticles, with the effective passivation generally achieved by organic functionalization. Photoexcited CDots are both potent electron donors and acceptors, and their characteristic bright and colorful fluorescence emissions make them excellent fluorescence sensors for organic analytes and metal ions. For the latter extraordinarily low detection limits based on extremely efficient quenching of fluorescence intensities by the targeted metal cations have been observed and reported in the literature. However, all of the dot samples in those reported studies were made from "one-pot" carbonization of organic precursors mostly under rather mild processing conditions, unlikely to be sufficient for the required level of carbonization. Those dot samples should therefore be more appropriately considered as "nano-carbon/organic hybrids", characterized structurally as being highly porous and spongy, which must be playing a dominating role in the reported sensing results. In this study, we compared the dot samples from carbonization syntheses under similarly mild and also more aggressive processing conditions with the classically defined and structured CDots for the fluorescence sensing of copper(ii) cations in aqueous solutions. The observed dramatic decoupling between quenching results for fluorescence intensities and lifetimes of the carbonization samples, with the former being extraordinary and the latter within the diffusion controlled limit, suggested that the quenching of fluorescence intensities was greatly affected by the higher local quencher concentrations than the bulk associated with the porous and spongy sample structures, especially for the sample from carbonization under too mild processing conditions. The major differences between the classical CDots and the nano-carbon/organic hybrids are highlighted, and the tradeoffs between sensitivity and accuracy or reproducibility in the use of the latter for fluorescence sensing are discussed.

Breast cancer is one of the most frequent malignant tumors in females. Extracts from Cortex Magnolia Officinalis (CMO) have shown the ability to inhibit the growth of breast cancer cells. In the present study, we developed MCF-7 cell membrane chromatography (CMC) combined with a UHPLC-ESI-MS/MS method to screen and identify the active components from the extract of CMO. Sorafenib and dexamethasone acetate were used as positive and negative control drugs, respectively, to investigate the suitability of this system. Under optimum experimental conditions, two components showed strong retention characteristics on the MCF-7 cell membrane chromatographic column. These compounds were identified as magnolol and honokiol by UHPLC-ESI-MS/MS. Cytotoxicity assay and Hoechst 33258 staining were done to investigate the anti-proliferative activity of the two compounds. The MTT results showed that MCF-7 cell viability decreased gradually in a dose-dependent manner during 48 h. The IC50 of magnolol and honokiol were 85.4 μM and 58.1 μM, respectively. After Hoechst 33258 staining, the cells were observed with bright blue nuclei due to karyopyknosis and chromatin condensation. The screening results showed that both magnolol and honokiol were promising active components of CMO extract having an inhibitory effect on MCF-7 cell growth. This two-dimensional method CMC-UHPLC-ESI-MS/MS could have potential utility for screening target components from traditional Chinese medicines.

Host–guest carbon dots (G@CDots) represent a new platform in the rapidly advancing and expanding research field of carbon “quantum” dots or carbon dots, enabling the development of novel carbon hybrid nanostructures of unique and/or advantageous properties and capabilities beyond those of conventional carbon dots. In this study, the red/near-IR emissive dye nile blue (NB) was selected as the guest, and NB@CDots were prepared in a microwave-assisted one-pot thermal carbonization synthesis with oligomeric polyethylene glycols (PEGs) as the precursor and also surface passivation species in the resulting host–guest dots. The NB@CDots exhibited unique and/or favorable characteristics, including especially the bright red/near-IR fluorescence emissions, with the observed fluorescence quantum yield due to the guest nile blue species more than an order of magnitude higher than that of free nile blue molecules, all in aqueous solutions. The higher fluorescence intensities were coupled with a longer fluorescence lifetime, and also accompanied by excellent photochemical stability, making the NB@CDots high-performance fluorescence probes for bioimaging-sensing and related applications. Indeed, their potential in this regard was explored and demonstrated in the fluorescence imaging of live stem cells. The NB@CDots were also evaluated in cytotoxicity assays, and the results suggested their being nontoxic. Excellent opportunities in further development of the host–guest carbon dots platform for high-performance yet nontoxic fluorescence probes are discussed.

Carbon dots are small carbon nanoparticles with various surface passivation schemes, in which more effective has been the deliberate chemical functionalization of the nanoparticles for brighter fluorescence emissions, even though the synthesis method is more tedious and subject to some limitations in the selection of functionalization molecules. Another more popular synthesis method has been the carbonization of organic species, with the method being more efficient and versatile, but less controllable regarding synthesis and achieving the desired dot structure and performance. In this work, a hybrid approach combining the advantageous characteristics of the two synthesis methods was applied to the preparation of carbon dots using polyethyleneimine (PEI) for surface passivation, where pre-processed and selected small carbon nanoparticles were functionalized with PEI by microwave-induced thermal reactions. Their optical absorption and fluorescence emission properties were evaluated, and the results suggested that the carbon dots thus prepared shared the same photoexcited state characteristics with those from the deliberate chemical functionalization, including comparable fluorescence colors and other properties. A further demonstration of the similarity in photoexcited state properties was based on the same visible light-activated bactericidal functions of the PEI-carbon dots as those found in carbon dots from the deliberate chemical functionalization method. The advantages and potential limitations of the hybrid approach for more controllable yet versatile and efficient syntheses of carbon dots are highlighted and discussed.

In order to develop an affinity HPLC method for screening direct thrombin inhibitors from Traditional Chinese Medicine (TCM), thrombin was immobilized on the glutaraldehyde-modified amino silica gel and was used as thrombin stationary phase. A thrombin affinity column (TAC) was made by packing the thrombin stationary phase into a bare column (2.0 * 1.0 mm, i.d.). The direct thrombin inhibitors could be screened through this TAC column. For the purpose of improvement of the discovery efficiency, a TAC-HPLC-MS/MS system was used to screen thrombin inhibitors from Radix Salviae Miltiorrhiae (RSM), a famous traditional Chinese medicine. After optimization of all the conditions, cryptotanshinone (Cry), dihydrotanshinone I (Dih-I) and tanshinone IIA (Tan-IIA) were screened out and identified as potential active components. The anticoagulant effects of these three compounds were tested by anticoagulant experiments in vitro. Furthermore, the interaction of three compounds with thrombin was studied by molecular docking. The result shows they have the potential to be used as preventive drugs. In short, this method can be used to screen anticoagulant drugs from traditional Chinese medicine, which provides convenience for screening anticoagulant drugs.

A heart-cutting two-dimensional high-performance liquid chromatography method was developed to simultaneously quantify five major proteins and seven food additives (maltol, ethyl maltol, vanillin, ethyl vanillin, benzoic acid, sorbic acid, and saccharin sodium) in milk and milk powders. In this two-dimensional system, a Venusil XBP-C4 column was selected in the first dimension for protein separation, and a Hypersil ODS-2 C18 column was employed in the second dimension for additive separation; a two-position, six-port switching valve was used to transfer the targets (additives) from the first dimension to the second dimension. Method validation consisted of selectivity, response function, linearity, precision, sensitivity, and recovery. In addition, a conventional one-dimensional high-performance liquid chromatography method was also tested for comparison. The two-dimensional method resulted in significantly improved recovery of the food additives compared to the conventional method (90.6-105.4% and 65.5-86.5%, respectively). Furthermore, this novel method has a simple one-step sample preparation procedure, which shortens the analysis time, resulting in more efficient analysis and less solvent usage.

A high-expression epidermal growth factor receptor cell membrane chromatography using the silica gel with the average particle size of 3 μm as the stationary phase carrier coupled with high-performance liquid chromatography and mass spectrometry was established for the online screening of epidermal growth factor receptor antagonists from Radix Scutellariae (Huang Qin in Chinese), a traditional Chinese medicine. In this study, the growth factor receptor cell membrane chromatography model using the smaller particle size carrier showed a higher efficiency for simultaneous screening baicalein, another one of the potential epidermal growth factor receptor antagonists from Radix Scutellariae extract besides wogonin, which was found in our previous work. The molecular docking result showed the occupancy site and binding mode of baicalein and wogonin with epidermal growth factor receptor tyrosine kinase were similar to gefitinib. The result of the assay for the in vitro inhibitory activity showed that baicalein and wogonin inhibited the growth of the high-expression epidermal growth factor receptor cell in a dose-dependent manner and even achieved a better inhibition effect than gifitinib in the low-dosage range.

A high expression α1A adrenoreceptor (α1AAR) cell membrane chromatography (CMC) combined with zonal elution method was developed to study the affinity interaction between the three kinds of alkaloid in Lotus Plumule and four kinds of alkaloid in Uncaria rhynchophylla with the α1AAR. HEK293 α1AAR cells were used for preparation of the CMC stationary phase. All measurements were performed with diode array detector at 37°C. In the self- and direct-competitive displacement assay, tamsulosin was used as competitor to evaluate the effects of the competitor’s concentration on the retention factor and the seven kinds of alkaloid, respectively. The competition behavior between tamsulosin and the seven alkaloids were also been examined. The results indicated that tamsulosin and other seven alkaloids had the same affinity sites on α1AAR. The association equilibrium constants (KA) values obtained were (2.99 ± 0.41) × 105 L/mol for tamsulosin, (6.26 ± 1.22) × 105 L/mol for liensinine, (7.59802 ± 1.81918) × 105 L/mol f...

A simple yet consequential modification was made to the popular carbonization processing of citric acid - polyethylenimine precursor mixtures to produce carbon dots (CDots). The modification was primarily on pushing the carbonization processing a little harder at a higher temperature, such as the hydrothermal processing condition of around 330 °C for 6 hours. The CDots thus produced are comparable in spectroscopic and other properties to those obtained in other more controlled syntheses including the deliberate chemical functionalization of preprocessed and selected small carbon nanoparticles, demonstrating the consistency in CDots and reaffirming their general definition as carbon nanoparticles with surface passivation by organic or other species. Equally significant is the finding that the modified processing of citric acid - polyethylenimine precursor mixtures could yield CDots of record-setting fluorescence performance, approaching the upper limit of being quantitatively fluorescent. Thus, the reported work serves as a demonstration on not only the need in selecting the right processing conditions and its associated opportunities in one-pot syntheses of CDots, but also the feasibility in pursuing the preparation of quantitatively fluorescent CDots, which represents an important milestone in the development and understanding of these fluorescent carbon nanomaterials.

Background: The gas human exhaled contains many volatile organic compounds (VOCs), which is related to the health status of body. Analysis of VOCs has been proposed as a noninvasive diagnostic tool for certain cancers. Detailed research on the VOCs in gas exhaled by cell can characterize cell type specific metabolites and may be helpful to detect the cancer markers in clinical practice. Methods: Solid-phase microextraction (SPME) gas chromatography–mass spectrometry was used to detect VOCs in the headspace of tissue culture flask in non-Hodgkin’s lymphoma (NHL) cell line JEKO and acute mononuclear leukemia cell line SHI-1, to elaborate the characteristic gaseous biomarkers of hematological malignancies. While macrophage cells and lymphocytic cells were acted as control. The blank group was only the RPMI 1640 medium containing 10% fetal calf serum that without cells. Results: Comparing with control group, the concentration of dimethyl sulfide, 2,4-dimethylheptane, methylbenzene, o-xylene, dodecane, and 1,3-di-tert-butylbenzene in JEKO cells was relatively higher, while the concentration of ethanol, hexanal, and benzaldehyde was lower. In SHI-1 cells, the levels of 2,4-dimethylheptane, benzene, 4-methyldecane, chloroform, 3,7-dimethyl dodecane, and hexadecane were significantly elevated, but the levels of hexanol and cyclohexanol were distinctly reduced. Conclusions: This pilot study revealed that the malignant hematological cells could change the components of VOCs in the cell culture flask in a cell type-specific pattern. The traits of VOCs in our setting offered new strategy for hematological malignancies tracing, and would act as potential biomarkers in diagnosis of malignant hematological diseases.

Maltol, ethyl maltol, vanillin, and ethyl vanillin are important food additives as flavor enhancers. To quantify the four additives in milk powder, a novel 2D liquid chromatographic (2DLC) method was developed in this article. In such a 2DLC system, the target fractions eluted from the first dimensional column (C4) are stored onto the trapping column (C8) for subsequent analysis; after that, they were switched into the second dimensional column (C18) by a two-position six-port switching valve. A one-step sample preparation method was used prior to 2DLC chromatographic analysis, which was easy and convenient. After optimization of all experimental parameters, the new method was validated in terms of linearity, LODs, and LOQs, intra- and interday precision, and accuracy. A conventional single-dimensional liquid chromatographic method was also proposed in this work for comparison. In order to evaluate the applicability of the new 2DLC method, five brands of commercial milk powder samples (n = 8) were analyzed. Vanillin and ethyl vanillin were detected in two samples, respectively. It is showed that the 2DLC method is effective in quality control programs of milk powder products.

Milk powder matrix is highly complex with significant amounts of lipids and proteins; thus, the determination of trace residues and contaminants in it often requires extensive sample extraction and preparation prior to instrumental analysis. An ideal preparation method is simple, less time consuming, and relatively inexpensive. It enhances the recovery and involves low consumption of toxic organic solvents. In this study, six sample preparation methods for milk powder were established and compared, including liquid–liquid extraction, organic precipitation, heavy precipitation, and three different solid-phase extraction (SPE) methods. The extraction recovery was evaluated by determination of six preservatives and sweeteners (benzoic acid, sorbic acid, natamycin, lysozyme, saccharin sodium, and aspartame) by HPLC-DAD in whole and skimmed milk powder samples. The results showed that the reproducibility of liquid–liquid extraction was not as high as the SPE method although the recovery was beyond 80 %; the organic precipitation and heavy precipitation gave poor recovery (below 20 %) of lysozyme; the highest recovery (>85 %) was achieved using the HLB cartridge compared to C18 and MAX cartridges. Therefore, the HLB cartridge was selected as the most appropriate sample preparation material for the determination of the six preservatives and sweeteners in milk powder samples by HPLC-DAD.

We describe here an analytical method of A431 cell membrane chromatography (A431/CMC) (CMC, cell membrane chromatography) combined with RPLC for recognition, separation, and identification of target components from traditional Chinese medicines (TCMs) Radix Caulophylli. The A431 cells with high expressed epidermal growth factor receptor (EGFR) were used to prepare the stationary phase in the CMC model. Retention fractions on the A431-CMC model were collected using an automated fraction collection and injection module (FC/I). Each fraction was analyzed by RPLC under the optimized conditions. Gefitinib and erlotinib were used as standard compounds to investigate the suitability and reliability of the A431 cell membrane chromatography-RPLC method prior to screening target component from Radix Caulophylli total alkaloids. The results indicated that caulophine and taspine were the target component acting on the epidermal growth factor receptor. This method could be an efficient way in drug discovery using natural medicinal herbs as a source of novel compounds.

We describe here an analytical method of HEK293 α1A AR cell membrane chromatography (HEK293 α1A AR/CMC) combined with reverse phase liquid chromatography (RPLC) for recognition, separation and identification of target components from Traditional Chinese Medicines (TCMs) Radix Caulophylli. The HEK 293 α1A cells with high expressing α1A adrenergic receptors were used to prepare the stationary phase in the CMC model. Retention fractions on the α1A AR–CMC model were collected using an automated fraction collection and injection module (FC/I). And each fraction was analyzed by RPLC under optimized conditions. 5-Methylurapidil (5-MU) and tamsulosin hydrochloride were used as standard compounds to investigate the suitability and reliability of the HEK 293 α1A AR–CMC–RPLC method prior to screening target component from Radix Caulophylli total alkaloid. The results indicated that caulophine was the target component acting on the α1A AR. This method could be an efficient way in drug discovery using natural medicinal herbs as a source of novel compounds.

We describe an analytical method of vascular smooth muscle cell membrane chromatography (VSM/CMC) combined with gas chromatography/mass spectrometry (GC/MS) for recognition, separation and identification of active components from traditional Chinese medicines (TCMs). VSM cells by means of primary culture with rat thoracic aortas were used for preparation of the stationary phase in the CMC model. Retention components by the VSM-CMC model were collected and then analyzed by GC/MS under the optimized conditions in offline conditions. After investigating the suitability and reliability of the VSM/CMC-offline-GC/MS method using nifedipine and nitrendipine as standard compounds, this method was applied in screening active components from the extracts of TCMs such as Radix Angelicae Dahuricae (RAD), Rhizomza Seu Radix Notopterygii (RSRN), Radix Glehniae (RG) and Fructus Cnidii (FC). Retention components from the extracts in the VSM-CMC model were imperatorin and osthole identified by the GC/MS method. In vitro pharmacological trials indicated that imperatorin and osthole could concentration dependently relax the rat thoracic artery pre-contracted by KCl (P

A high-expression epidermal growth factor receptor cell membrane chromatography using the silica gel with the average particle size of 3 μm as the stationary phase carrier coupled with high-performance liquid chromatography and mass spectrometry was established for the online screening of epidermal growth factor receptor antagonists from Radix Scutellariae (Huang Qin in Chinese), a traditional Chinese medicine. In this study, the growth factor receptor cell membrane chromatography model using the smaller particle size carrier showed a higher efficiency for simultaneous screening baicalein, another one of the potential epidermal growth factor receptor antagonists from Radix Scutellariae extract besides wogonin, which was found in our previous work. The molecular docking result showed the occupancy site and binding mode of baicalein and wogonin with epidermal growth factor receptor tyrosine kinase were similar to gefitinib. The result of the assay for the in vitro inhibitory activity showed that baicalein and wogonin inhibited the growth of the high-expression epidermal growth factor receptor cell in a dose-dependent manner and even achieved a better inhibition effect than gifitinib in the low-dosage range.

To classify thrombosis and pectinate muscle in cardiac ultrasound image sequences, a classification method based on sparse representation is proposed. This method extracts GLCM based texture features to form the sample set and compute the sparse solution with coefficients how a test sample be represented by the training set. After that, two kinds of constraints and classification strategy are added to achieve the classification. Experiment results shows that the proposed approach can achieve a classification accuracy of 91.92%, significantly higher than other popular classifiers.

Traditional Chinese medicines (TCMs) have been used for preventative care for thousands of years. The active components are the basis for the pharmacodynamics of TCMs, and they can be an important source of lead compounds. As a bioaffinity chromatography technique, cell membrane chromatography (CMC) has been developed for almost 20 years since 1996. It has been proven to be a useful method for studying drug-receptor interactions and screening active components from medicinal herbs. In our review in 2007 (Drug Discov. Ther., 1 (2007) 104-107), the preparation, identification, evaluation, and preliminary applications of CMC stationary phases were presented. In this article, we briefly review some of the latest progress and applications about CMC including instrument development, research on drug-receptor interactions, screening active components from TCMs, and quality control of TCMs.

Maltol, ethyl maltol, vanillin, and ethyl vanillin are important food additives as flavor enhancers. To quantify the four additives in milk powder, a novel 2D liquid chromatographic (2DLC) method was developed in this article. In such a 2DLC system, the target fractions eluted from the first dimensional column (C4) are stored onto the trapping column (C8) for subsequent analysis; after that, they were switched into the second dimensional column (C18) by a two-position six-port switching valve. A one-step sample preparation method was used prior to 2DLC chromatographic analysis, which was easy and convenient. After optimization of all experimental parameters, the new method was validated in terms of linearity, LODs, and LOQs, intra- and interday precision, and accuracy. A conventional single-dimensional liquid chromatographic method was also proposed in this work for comparison. In order to evaluate the applicability of the new 2DLC method, five brands of commercial milk powder samples (n = 8) were analyzed. Vanillin and ethyl vanillin were detected in two samples, respectively. It is showed that the 2DLC method is effective in quality control programs of milk powder products.

In this study, a new"heart-cutting" two-dimensional liquid chromatography method for the simultaneous determination of carbohydrate contents in milk powder was presented. In this two dimensional liquid chromatography system, a Venusil XBP-C4 analysis column was used in the first dimension ((1)D) as a pre-separation column, a ZORBAX carbohydrates analysis column was used in the second dimension ((2)D) as a final-analysis column. The whole process was completed in less than 35min without a particular sample preparation procedure. The capability of the new two dimensional HPLC method was demonstrated in the determination of carbohydrates in various brands of milk powder samples. A conventional one dimensional chromatography method was also proposed. The two proposed methods were both validated in terms of linearity, limits of detection, accuracy and precision. The comparison between the results obtained with the two methods showed that the new and completely automated two dimensional liquid chromatography method is more suitable for milk powder sample because of its online cleanup effect involved.

Most of the anti-breast cancer drugs are often limited owing to drug resistance and serious adverse reactions. Therefore, development of more targeted and low toxic drugs from traditional Chinese medicines for breast cancer are needed. At the same time, establishment of fast and effective drug screening methods are urgently required. We describe here a 2D LC method of MDA-MB-231 cell membrane chromatography combined with HPLC/MS for recognition, separation, and identification of target components from traditional Chinese medicine Cortex Magnolia officinalis. The MDA-MB-231 cells membrane was used to prepare the chromatographic stationary phase in the first dimension. The active compounds had a retention characteristic on the cell membrane chromatography model (10 × 2.0 mm, 5 μm). The retention fractions were enriched using an online C(18) column (10 × 1.0 mm, 5 μm) and were analyzed by the second dimension RP chromatography. Finally, the activity of the retention fractions was tested through in vitro experiments. Results showed that the retention fractions were honokiol and magnolol and the inhibition rate on MDA-MB-231 cell growth were 23 and 64 μM, respectively. These results support the conclusion that this coupled analytical technique could be an efficient method in drug discovery.

In China, traditional Chinese medicines (TCMs) have been used in clinical applications for thousands of years. The successful hyphenation of high-Performance liquid chromatography (HPLC) and mass spectrometry (MS) has been applied widely in TCMs and biological samples analysis. Undoubtedly, HPLC/MS technique has facilitated the understanding of the treatment mechanism of TCMs. We reviewed more than 350 published papers within the last 5 years on HPLC/MS in the analysis of TCMs. The present review focused on the applications of HPLC/MS in the component analysis, metabolites analysis, and pharmacokinetics of TCMs etc. 50% of the literature is related to the component analysis of TCMs, which show that this field is the most populär type of research. In the metabolites analysis, HPLC coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry has been demonstrated to be the powerful tool for the characterization of structural features and fragmentation behavior patterns. This paper presented a brief overview of the applications of HPLC/MS in the analysis of TCMs. HPLC/MS in the fingerprint analysis is reviewed elsewhere. Keywords: traditional Chinese medicines (TCMs), HPLC/MS, component analysis, metabolites analysis, pharmacokinetics

We describe here an analytical method of A431 cell membrane chromatography (A431/CMC) (CMC, cell membrane chromatography) combined with RPLC for recognition, separation, and identification of target components from traditional Chinese medicines (TCMs) Radix Caulophylli. The A431 cells with high expressed epidermal growth factor receptor (EGFR) were used to prepare the stationary phase in the CMC model. Retention fractions on the A431-CMC model were collected using an automated fraction collection and injection module (FC/I). Each fraction was analyzed by RPLC under the optimized conditions. Gefitinib and erlotinib were used as standard compounds to investigate the suitability and reliability of the A431 cell membrane chromatography-RPLC method prior to screening target component from Radix Caulophylli total alkaloids. The results indicated that caulophine and taspine were the target component acting on the epidermal growth factor receptor. This method could be an efficient way in drug discovery using natural medicinal herbs as a source of novel compounds.

In this paper we proposed a design of a Java co-processor for a 32-bit RISC system to improve its performance, as the software only Java interpreter is more time-consuming. Our work includes the hardware/software co-design of the Java Card Virtual Machine (JCVM) and the details of its hardware implementation. The JCVM translates the Java bytecodes (JBCs) into the native RISC instructions and then passes them to the RISC core. A 16-byte pre-fetch FIFO and the folding mechanism are applied to further speedup the translation.

As a preliminary stage of drug discovery, the screening of active compounds from complex systems requires efficient and accurate techniques. In our study, a two dimensional liquid chromatography method was developed for the fast screening of anti-breast cancer compounds. MDA-MB-231 cell membrane chromatography and high performance liquid chromatography/mass spectroscopy was combined online for recognition, separation, and identification of target components from the traditional Chinese medicine Fructus evodiae. Here, the breast cancer cells MDA-MB-231 were used to prepare the chromatographic stationary phase in the first dimension. The target compounds had a retention characteristic on cell membrane chromatography. The retention fraction was enriched using an online C18 column and was analyzed by the second dimensional reversed phase chromatography. Finally, the activity of the retention fractions was tested through in vitro experiments. Results showed that the target compounds were evodiamine and rutaecarpine and their IC50 values were 33.4 μM and 73.4 μM, respectively, which illustrated that they could inhibit the growth of MDA-MB-231 cells. These results support the conclusion that this coupled analytical technique could be an efficient method in drug discovery.