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Overweight and obesity are the causes of many diseases and have become global "epidemics". Research on natural active components with anti-adipogenesis effects in plants has aroused the interest of researchers. One of the most critical problems is establishing sample preparation and analytical techniques for quickly and selectively extracting and determining the active anti-adipogenesis components in complex plant matrices for developing new anti-adipogenic drugs. In this study, a new poly(deep eutectic solvents) surface imprinted graphene oxide composite (PDESs-MIP/GO) with high selectivity for phenolic acids was prepared using deep eutectic solvents as monomers and crosslinkers. A miniaturized centrifugation-accelerated pipette-tip matrix solid-phase dispersion method (CPT-MSPD) with PDESs-MIP/GO as adsorbent, coupled with high-performance liquid chromatography, was further developed for the rapid determination of anti-adipogenesis markers in Solidago decurrens Lour. (SDL). The established method was successfully used to determination anti-adipogenesis markers in SDL from different regions, with the advantages of accuracy (recoveries: 94.4 - 115.9 %, RSDs ≤ 9.8 %), speed (CPT-MSPD time: 11 min), selectivity (imprinting factor: ∼2.0), and economy (2 mg of adsorbent and 1 mL of solvents), which is in line with the current advanced principle of "3S+2A" in analytical chemistry., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Alectinib is known as an effective targeted drug, which has excellent therapeutic effect on non-small cell lung cancer and can significantly prolong the survival of patients. Therapeutic drug monitoring is necessary due to the photo-instability of alectinib and the individual differences in patients. In this work, a porous polydopamine graphene oxide composite (PDAG) was prepared by a simple surface modification method. A PDAG-based pipette-tip solid-phase extraction (PT-SPE) coupled with HPLC-UV detection was proposed for the separation and detection of alectinib and its active metabolite M4 in plasma. The method was methodologically validated and showed good linearity in the range of 50-5000 ng mL -1 (R 2  > 0.9995). The limit of detection (LOD) was 4.8 ng mL -1 and 3.9 ng mL -1 for alectinib and M4, respectively, and the limit of quantitation (LOQ) was 16.1 ng mL -1 and 13.1 ng mL -1 , respectively. The intra-day and inter-day precision expressed by coefficient of variation was less than 4.8 %. The recovery of this method ranged from 84.9 % to 103.5 % with a standard deviation of less than 4.3 %. In conclusion, the established method is accurate, stable and inexpensive, and can be used to monitor the levels of alectinib and M4 in plasma, which provide technical and data support for exploring optimal individualized remedial dosing regimens., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Long-term exposure to halobenzoquinones (HBQs) can induce genomic damages and abnormal epigenetic modifications. High-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) has shown unique advantages in identification and sensitive analysis of these structurally modified DNA lesions. Prior to MS analysis, genomic DNA needs to be fully digested into mono-nucleosides. Here, we prepared Supernuclease (SN)-, snake venom phosphodiesterase (SVP)- and calf intestinal alkaline phosphatase (CIP)- individually immobilized magnetic nanoparticles (MNPs), and combined them according to certain formula to construct a recyclable SN-SVP-CIP magnetic nanoparticles (SNSC-MNPs) cascade for rapid and efficient DNA digestion. The SNSC-MNPs cascade can fully digest genomic DNA into mono-nucleosides within 30 min. The SNSC-MNPs cascade coupled with HPLC-MS/MS method can accurately and sensitively detect 5-hydroxymethylcytosine (5hmC) changes in genome of human bladder cancer T24 cells induced by tetrachlorobenzoquinone. The immobilization of enzymes on MNPs can enhance the stability and enzymatic activity of the three enzymes, which guarantees the reusability and longtime preservation of the cascades. The relative digestive efficiencies are among 86% -106% up to ten times of reuse. The newly synthesized SNSC-MNPs cascade coupled with HPLC-MS/MS method is promising for fast identification and analysis of structural modifications in genomic DNA., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

8-Hydroxydeoxyguanosine (8-OHdG) is a widely-used biomarker of oxidative DNA damages. 8-OHdG in peripheral blood leukocyte is associated with mutation and cancer risk. The level of 8-OHdG in peripheral blood leukocytes can indicate a long-term response to oxidative stress rather than that in urine. Accurate identification and quantification of leukocyte 8-OHdG are essential for understanding its mechanism of formation, repair, and biological consequences. In this study, a fast and accurate ultra-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated to detect 8-OHdG in human peripheral leukocyte. DNA in blood samples were extracted and digested, then subjected onto UHPLC-MS/MS using an isocratic elution on a Zorbax Eclipse Plus C18 column (2.1×100mm, 1.8μm). Multiple reaction monitoring (MRM) mode was adopted by using [ 15 N 5 ]-8-OHdG as an internal standard. The assay was linear over the concentration range of 1.0-100nM with R 2 =0.999. The accuracy for spiked samples was 90.9%-94.8%, and the intra-day precision was within 3.7%. The limit of detection (LOD) is 0.30nM and limit of quantification (LOQ) is 1.0nM with 5μl of sample injection. By the analysis of human leukocyte 8-OHdG (n=121) using the developed UHPLC-MS/MS method, it demonstrates that the level of leukocyte 8-OHdG of the cancer patients group (n=46) is significantly higher than that of the health control (n=75)., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A DNA aptamer based high-performance affinity chromatography is developed for selective extraction and screening of a basic protein lysozyme. First, a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolithic column was synthesized in situ by thermally initiated radical polymerization, and then an anti-lysozyme DNA aptamer was covalently immobilized on the surface of the monolith through a 16-atom spacer arm. The target protein lysozyme but non-target proteins can be trapped by the immobilized anti-lysozyme DNA aptamer. In contrast, lysozyme cannot be trapped by the immobilized oligodeoxynucleotide that does not contain the sequence of the anti-lysozyme DNA aptamer. The study clearly demonstrates the trapping of lysozyme by the immobilized anti-lysozyme DNA aptamer is mainly due to specific recognition rather than simple electrostatic interaction of positively charged protein and the negatively charged DNA. The inter-day precision was determined as 0.8% for migration time and 4.2% for peak area, respectively. By the use of aptamer affinity monolith, a screening strategy is developed to selectively extract lysozyme from chicken egg white, showing the advantages of high efficiency, low cost and ease-of-operation., (Copyright © 2012 Elsevier B.V. All rights reserved.)

To assess the potential risks associated with the environmental exposure of beta-lactam antibiotics (BLAs), the monitoring of the occurrence, distribution, and fate of these emerging contaminants in the environment is required. Herein, we demonstrate a molecularly imprinted solid-phase extraction (MISPE) method for selective and reliable screening of trace BLAs in river and tap water. By developing a low-temperature photopolymerization, highly selective molecularly imprinted polymers (MIPs) for five BLAs (penicillin G, amoxicillin, ampicillin, nafcillin and mezlocillin) were synthesized. Nafcillin was chosen as a pseudo template to make the MIP sorbent (Nafc-MIP), which was used in pseudo-template MISPE for preconcentration of the other four BLAs from river and tap water. The application of pseudo-template MISPE overcomes the template bleeding, which significantly elevates the sample background and restricts the application of MIP for detection of the target BLA below 2 microg/L. The average recoveries of BLAs are in the range of 60-90% when Nafc-MIP was adopted as the selective MISPE sorbent. The developed method was validated, and applied to the screening of trace beta-lactam antibiotics in river and tap water. The linearity of the calibration curve for each BLA was observed over the range of 0.1-20 microg/L (r>0.998). The beta-lactam antibiotics were found within the range of 0-9.56 microg/L in river water at the downstream of antibiotics manufacturers, and none were detected in the tap water., (2010 Elsevier B.V. All rights reserved.)

The detection and quantification of disease-related proteins play critical roles in clinical practice and diagnostic assays. We present an affinity probe capillary electrophoresis/laser-induced fluorescence polarization (APCE/LIFP) assay for detection of human thrombin using a specific aptamer as probe. In the APCE/LIFP assay, the mobility and fluorescence polarization of complex are measured simultaneously during CE analysis. The affinity complex of human thrombin can be well separated from unbound aptamer on CE and clearly identified on the basis of its fluorescence polarization and migration. Because of the binding favorable G-quartet conformation potentially involved in the specific aptamer, it was assumed that monovalent and bivalent cations promoting the formation of a stable G quadruplex conformation in the aptamer may enhance the binding of the aptamer and thrombin. Therefore, we investigated the effects of various metal cations on the binding of human thrombin and the aptamer. Our results show that cations like K(+) and Mg(2+) could not stabilize the affinity complex. Without the use of typical cations, a highly sensitive assay of human thrombin was developed with the corresponding detection limits of 4.38x10(-19) and 2.94x10(-19)mol in mass for standard solution and human serum, respectively.

Monolithic silica columns have inspired considerable research interests in the separation science because of their unique properties in permeability, mass transfer, efficiency and throughput. In this paper, a chemically p-tert-butylcalix[8]arene-bonded silica monolith was prepared as the promising candidate for versatile LC separations. Micrometer-sized macropores and nanometer-sized mesopores in this derivatized silica monolith reduce the diffusion path length and provide both low backpressure and high column efficiencies, leading to high-speed and high-throughput separations. Since p-tert-butylcalix[8]arene possesses a pi-donors cavity composed of benzene rings while polycyclic aromatic hydrocarbons, anthraquinones, phenol regio isomers and fullerenes are pi-systems with appreciable electron affinity, they may have a chance to get involved in forming host-guest inclusion complexes through non-covalent interactions, e.g. hydrophobic and pi-pi interactions. Compared with RP-18e, the prepared calixarene-bonded monolith exhibited better selectivity to molecules which contains more pi-electrons and more condensed cyclic moieties. The column efficiency was about 22,000 plates/m. The calixarene-bonded monolith also showed its good performances in separation of fullerenes and dihydropyridines, indicating a promising approach for purification of fullerenes with high purity from the carbon soot.

Benzo[a]pyrene, a common environmental pollutant, can be metabolized into reactive anti-benzo[a]pyrene diol epoxide (anti-BPDE), which predominantly binds to deoxyguanine in DNA and forms four stereoisomeric adducts. To characterize the stereochemistry of these adduct isomers, preparation of single adducted deoxyguanosine (dG) is required for efficient enantiomeric analysis. Here, we demonstrate an improved method for preparation, identification, and analysis of four BPDE-adducted dGs, including (+)-trans-, (-)-trans-, (+)-cis-, and (-)-cis-anti-BPDE-N(2)-dG. These stereoisomerically adducted nucleosides were first synthesized by a direct reaction of (+/-)-anti-BPDE with dG, followed by optimized solid-phase extraction (SPE) and HPLC purification. The reaction of (+/-)-anti-BPDE and dG displayed a yield as high as 45%. The developed preparation method does not require any enzymatic digestion. Based on highly efficient separation achieved by optimization of stationary phase and mobile phase, LC-UV-MS/MS and LC-diode array detection (DAD)-fluorescence detection (FL) methods were established for characterization and analysis of the four stereoisomeric anti-BPDE-dGs. The established LC-DAD-FL method may provide characterization and analysis of four stereoisomeric anti-BPDE-dGs and two interfering anti-BPDE tetrols by taking advantage of their distinct fluorescence quenching.

A weak ion exchange monolithic column prepared by modifying the GMA-MAA-EDMA (glycidyl methacrylate-methacrylic acid-ethylene glycol dimethacrylate) monoliths with ethylenediamine was applied to remove matrix compounds in biological fluid. Using this monolithic column, on-line clean-up and screening of oxacillin and cloxacillin in human urine and plasma samples had been investigated. Chromatography was performed by reversed-phase HPLC on a C(18) column with ultraviolet detection at 225 nm. Results showed that the ion exchange monolithic column could be used for deproteinization and retaining oxacillin and cloxacillin in human urine and plasma, which provided a simple and fast method for assaying drugs in human urine and plasma.

A molecularly imprinted solid-phase extraction coupled with high performance liquid chromatography (MISPE-HPLC) method was developed for rapid screening of mycophenolic acid (MPA) in human plasma. MPA imprinted polymers (MPA-MIP) were synthesized and then tested for their performance both in organic and in aqueous solution. MPA was selectively trapped and preconcentrated on the MPA-MIP sorbent using different loading and washing conditions. The good selectivity of MPA-MIP enabled further clean-up of the interfering components in human plasma. For the proposed MISPE-HPLC method, the linearity between responses (peak area) and concentration was found over the range of 1-100microg/ml with a linear regression coefficient (R(2)) of 0.9989. The limit of detection (LOD) and theoretical limit of quantification (LOQ) for MPA in plasma were 0.10 and 0.32microg/ml, respectively. The precisions were 7.3, 3.5 and 4.7% RSD for intra-day assay and 9.2, 4.1 and 5.5% RSD for inter-day reproducibility, respectively, at three concentration levels of MPA in spiked plasma (1, 10 and 100microg/ml). Both recoveries for the extraction (more than 74%) and for the analytical method (more than 87%) were acceptable for screening MPA in plasma samples. Twelve-hour pharmacokinetic profile of MPA for a renal transplant recipient receiving chronic oral dosing of 500mg mycophenolate mofetil (MMF) was investigated. Results indicated that this method could be applied for therapeutic drug monitoring of mycophenolic acid in patient plasma.

A weak cation-exchange monolithic column was prepared by modifying the GMA-EDMA (glycidyl methacrylate-co-ethylene glycol dimethacrylate) monoliths with ethylenediamine and monochloracetic acid. The properties of the column were investigated; the column exhibited the ability of low backpressure and fast analysis. Using this monolithic column, trace doxazosin in human serum albumin (HSA) solution and plasma samples has been on-line tested, the extraction efficiency and the maximum loading capacity of the monolithic column were obtained. The results showed that the monolithic column could realize deproteinization and trace drug enrichment simultaneously in the HSA solution and human plasma, which provided a simple, cheap, effective and friendly to environment method for assaying drugs in the blood.

A high-performance liquid chromatography (HPLC) method with evaporative light scattering detection (ELSD) was applied for simultaneous determination of stachyose, sucrose and raffinose in Chinese artichoke (Stachys Sieboldii Miq.). Carbohydrates were separated on a Bondapak NH(2) column using a ternary solvent mixture of methanol-acetonitrile-water (55:25:20, v/v/v) as mobile phase. Two different crafts (method 1 and method 2) for extraction and purification of stachyose in Chinese artichoke tubers were detailed and evaluated. Method 1 can meet the purpose of quantification and method 2 is appropriate for the purpose of purification. The content of stachyose in dry tubers was determined to be 236.0mg/g (from method 1) and the purity of the extracted stachyose flour was calculated to be 87.34% (from method 2), respectively. The analytical method fulfills all the standard requirements of linearity, accuracy and precision. Therefore, it is suitable for purification and routine quantification of stachyose in Chinese artichoke.

A monolithic molecularly imprinted polymer (monolithic MIP) was designed and prepared for chiral separation of nateglinide and its L-enantiomer. The enantiomers were rapidly separated on this novel monolithic MIP based chiral stationary phase (MIP-CSP), whereas the enantioseparation was not obtained on the non-imprinted polymer (NIP). Chiral recognition was found to be dependent on the stereo structures and the arrangement of functional groups of the imprinted molecule and the cavities on MIP. Thermodynamic data (deltadeltaH and deltadeltaS) obtained by Van't Hoff plots revealed an enthalpy-controlled enantioseparation. The binding capacity was evaluated by frontal analysis. Monolithic nateglinide-MIP had an effective number of binding sites Bt = 41.15 micromol g(-1) with a dissociation constant of Kd = 7.40 mM. The morphological characteristics of the monolithic MIP were investigated by pore analysis and scanning electron microscope (SEM). Results showed that both mesopores and macropores were formed in the monolith. Over all, this study presents a new and practical possibility for providing high rates of mass transfer, fast separations and high efficiencies without the pressure constraints of the traditional bulk molecularly imprinted polymers, through the monolithic MIPs.