Journal of Materials Chemistry B
·
2013
·Vol. 1
·期 10
·1491-1500
·
IF 0
Zhi-Gang Wang,Gong Cheng,Yan-Lin Liu,Ji-Lin Zhang,De-Hui Sun,Jia-Zuan Ni
The multifunctional microspheres consisting of the magnetic γ-Fe2O3 core and the affinity REVO4 (RE = Sm, Dy, Ho) shell have been synthesized via the homogenous precipitation–calcination–ion exchange three-step synthetic route. Their morphologies, structures, surface properties, and magnetisms were characterized, respectively. SEM and TEM images indicate that they all have an average size of about 400 nm and very rough surfaces. The TEM images further reveal that the γ-Fe2O3@REVO4 microspheres are all core–shell structures and the REVO4 shells are about 55–60 nm in thickness. The XRD pattern analyses show that the magnetic γ-Fe2O3 cores belong to cubic structure and the REVO4 (RE = Sm, Dy, Ho) shells are composed of their corresponding tetragonal major phases. HRTEM images, FTIR spectra and EDS further demonstrate the formations of tetragonal REVO4 shells based on checkup of the corresponding lattice fringes, characteristic IR absorption peaks and element signals. Their potentials for selective capture, rapid separation, and convenient mass spectra (MS) labeling of the phosphopeptides from complex proteolytic digests are explored and evaluated for the first time. The experimental results show that the magnetic γ-Fe2O3@REVO4 core–shell structured microspheres have high selective affinity for the phosphopeptides. The trapped phosphopeptides can be rapidly isolated by an external magnetic field, and can be easily identified by characteristic MS signals from 80 Da mass losses in the mass spectra (MS). Additionally, the γ-Fe2O3@REVO4 affinity materials can be reused after recovery.
研究领域:
材料科学
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分析化学
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生物化学
✓ 已验证
DOI
PubMed
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
·
2014
·
IF 2.694
Yunfang Li,Yu Chen,Chuying Xiao,Dan Chen,Yuxiu Xiao,Zhinan Mei
α-Amylase inhibitors play an important role in management of diabetes and obesity. In order to rapidly discover potent α-amylase inhibitors from medicinal plants, a ligands-screening method based on enzyme-immobilized magnetic nanoparticles integrated with HPLC was developed. Amine-terminated magnetic nanoparticles were prepared for the immobilization of α-amylase. Based on the affinity theory, the α-amylase-coated magnetic nanoparticles were employed to fish out the ligands from the extracts of Garcinia xanthochymus , and the elutes were examined by HPLC. As a result, three ligands were screened out. Isolation and identification were carried out subsequently. By analyzing the UV, MS and NMR spectra, they were identified as three biflavonoids including GB2a glucoside (2), GB2a (3) and fukugetin (4). The IC 50 values of the three compounds were also determined. The results suggest the proposed approach is efficient and accurate, and has great potential in rapid discovery of drug candidates from medical plants.
研究领域:
药理学
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生物化学
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药物发现
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
·
2020
·
IF 3.255
Yang Tian,Qiuyu Bao,Nian Wang,Ning Wan,Langlang Lv,Haiping Hao,Chaoyong He,Hui Ye
Elucidating ligand–protein interactions is important in understanding the biochemical machinery for given proteins. Previously, formaldehyde (FH)-based labeling has been employed to obtain such structural knowledge, since reactive residues that participate in ligand–target interactions display reduced accessibility to FH-labeling reagents, and thus can be identified by quantitative proteomics. Although being rapid and efficient for probing proteinaceous lysine accessibility, here, we report an acetaldehyde (AcH)-labeling approach that complements with FH for probing ligand–target interactions. AcH labeling examines lysine accessibility at a more moderate reaction speed and hence delivers a cleaner reaction when compared to that of FH. The subsequent application of AcH to label RNase A without and with ligands has assisted to assign lysines involved in ligand–RNase A binding by detecting the time-dependent changes in accessibility profiles. We further employed multiple reaction monitoring (MRM) to quantify these ligand-binding-responsive sites when a variety of potential ligands were queried. We noted that the time-resolved abundance changes of these peptides can sensitively determine the ligand-binding sites and differentiate binding affinities among these ligands, which was confirmed by native mass spectrometry (MS) and molecular docking. Lastly, we demonstrated that the binding sites can be recognized by monitoring the chemical accessibility of these responsive peptides in cell lysates. Together, we believe that the proposed combined use of AcH-based lysine accessibility profiling, native MS, and MRM screening is a powerful toolbox in characterizing ligand–target interactions, mapping topography, and interrogating affinities and holds promise for future applications in a complex cellular environment.
研究领域:
化学
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生物化学
·
蛋白质组学
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结构生物学
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药物发现
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2017
·Vol. 183
·期 4
·1488-1502
·
IF 1.751
Wang Liming,Chen Yan
Cycloastragenol (CA), an exclusive telomerase activator, was derived from the Astragali Radix which is widely distributed in Turkey. Until now, there is no report to produce CA with effective and environment-friendly methods. Biotransformation is considered to be a promising technology. Thus, the present study was aimed to establish a biotransformation technology that could efficiently produce CA. In this paper, a microorganism, LG-502, was used to successfully transform astragaloside IV (ASI) to CA by analysis of thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). The phylogenetic analysis of the 16S rRNA indicated that this strain belongs to Bacillus sp. Three metabolites were separated during the fermentation and characterized to be cyclogaleginoside B, CA, and 20 R , 24 S -epoxy-6 α , 16 β , 25-trihydroxy-9, 19-cycloartan-3-one based on NMR and MS spectroscopic analyses. The conversion rate of ASI and yield rate of CA were achieved as high as 89 and 84%, respectively, under optimized conditions. Enzymatic analysis showed that the glycosidases were mainly located inside the bacterial body, and the activities of glucosidases were much higher than the xylosidases under the experimental conditions. This study provides a feasible, effective, and eco-friendly way to prepare CA from ASI, which might greatly contribute to the applications of ASI.
研究领域:
药学
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生物技术
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微生物学
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有机化学
✓ 已验证
DOI
PubMed
高影响因子
Pharmaceutics
·
2024
·Vol. 16
·期 9
·1178
·
IF 4.9
Xiao Duan,Qiang Wang,Yue Wang,Xinping Liu,Manman Lu,Zhifang Li,Xuelian Jiang,Jingquan Ji
Using an endogenous carrier is the best method to address the biocompatibility of carriers in the drug delivery field. Herein, we prepared a glutathione-responsive paclitaxel prodrug micelle based on an endogenous molecule of L-glutathione oxidized (GSSG) for cancer therapy using one-pot synthesis. The carboxyl groups in L-glutathione oxidized were reacted with the hydroxyl group in paclitaxel (PTX) using the catalysts dicyclohexylcarbodiimide (DCC) and 4-dimethylaminopyridine (DMAP). Then, the amino-polyethylene glycol monomethyl ether (mPEG-NH2) was conjugated with GSSG to prepare PTX-GSSG-PEG. The structure of PTX-GSSG-PEG was characterized using infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR), and mass spectrometry (MS). The drug release kinetics of PTX within PTX-GSSG-PEG were quantified using ultraviolet spectroscopy (UV-Vis). The size of the PTX-GSSG-PEG micelles was 83 nm, as evaluated using dynamic light scattering (DLS), and their particle size remained stable in a pH 7.4 PBS for 7 days. Moreover, the micelles could responsively degrade and release PTX in a reduced glutathione environment. The drug loading of PTX in PTX-GSSG-PEG was 13%, as determined using NMR. Furthermore, the cumulative drug release rate of PTX from the micelles reached 72.1% in a reduced glutathione environment of 5 mg/mL at 120 h. Cell viability experiments demonstrated that the PTX-GSSG-PEG micelles could induce the apoptosis of MCF-7 cells. Additionally, cell uptake showed that the micelles could distribute to the cell nuclei within 7 h. To sum up, with this glutathione-responsive paclitaxel prodrug micelle based on the endogenous molecule GSSG, it may be possible to develop novel nanomedicines in the future.
研究领域:
药学
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纳米技术
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癌症研究
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药物递送系统
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）