Elevated hydrogen peroxide (HO) levels not only inflict cellular damage but also serve as a harbinger for various diseases. Tumor cells, in particular, often exhibit an abundance of HO. Hence, the detection of this pivotal molecule assumes paramount importance in monitoring physiological states and expediting cancer diagnosis.
View Article and Find Full Text PDFThe concept of reference sample was put forward in the Guidance on CMC of Traditional Chinese Medicine Compound Preparations Developed from Catalogued Ancient Classical Prescriptions(Interim). The research on reference sample is a key link in the research and development of traditional Chinese medicine(TCM) compound prescriptions from catalogued ancient classical prescriptions(known as Category 3.1 TCM).
View Article and Find Full Text PDFConventional collagen-based hydrogels as wound dressing materials are usually lack of antibacterial activity and easily broken when encountering external forces. In this work, we developed a collagen peptide-based hydrogel as a wound dressing, which was composed of adipic acid dihydrazide functionalized collagen peptide (Col-ADH), oxidized dextran (ODex), polyvinyl alcohol (PVA) and borax via multiple-dynamic reversible bonds (acylhydrazone, amine, borate ester and hydrogen bonds). The injectable hydrogel exhibited satisfactory self-healing ability, antibacterial activity, mechanical strength, as well as good biocompatibility and biodegradability.
View Article and Find Full Text PDFThe development of drug delivery systems with high drug loading capacity, low leakage at physiological pH, and rapid release at the lesion sites remains an ongoing challenge. In this work, core-shell poly(6--methacryloyl-D-galactose)@poly(-butyl methacrylate) (PMADGal@PBMA) nanoparticles (NPs) of sub-50 nm are facilely synthesized by reversible addition-fragmentation chain transfer (RAFT) soap-free emulsion polymerization with the assistance of 12-crown-4. A hydrophilic poly(methacrylic acid) (PMAA) core can then be revealed after deprotection of the -butyl groups, which is negatively charged and can adsorb nearly 100% of incubated doxorubicin (DOX) from a solution at pH 7.
View Article and Find Full Text PDFGalactosylated core-shell nanoparticles (NPs) with diameters of sub-50 nm were fabricated in one pot by reversible addition-fragmentation chain transfer (RAFT) soap-free emulsion polymerization. Their galactosylated shells and acidic cores endow them with high targeting and drug loading efficiencies, respectively. Morever, the physical shrinkage and cleavage of the disulfide cross-linked NPs can realize the rapid release of loaded doxorubicin (DOX) under pH 5.
View Article and Find Full Text PDFThe hierarchically bicontinuous polystyrene monoliths (HBPMs) with homogeneous skeletons and glycopolymer surfaces are fabricated for the first time based on the medium internal phase emulsion (MIPE) templating method via activator generated by electron transfer for atom transfer radical polymerization (AGET ATRP). The synergistic self-assembly of amphiphilic diblock glycopolymer (ADG) and Pluronic F127 (PF127) at the oil/water interface via hydrogen bonding interaction contributes to the formation of bicontinuous MIPE with deformed neighboring water droplets, resulting in the highly interconnected HBPM after polymerization. There is a bimodal pore size distribution in the HBPM, that is, through pores (150-5000 nm) and mesopores (10-150 nm).
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
April 2021
In leading the high-quality development of Chinese medicine preparations, it is an important link to formulate the scientific, reasonable, and feasible guidelines for the change of Chinese medicines in accordance with the change characteristics and principles of the Chinese medicines is an important work to promote the Technical guidelines for the study of pharmaceutical changes in traditional Chinese medicines was formed by a broad consensus based on the characteristics and research results of the pharmaceutical changes in Traditional Chinese Medicines(TCM)with the principles of science and risk management. This guideline has clarified the basic principles and requirements for the evaluation of changes in TCM, specified the research and verification work of common change scenarios, defined the boundaries of changes in TCM, and proposed to encourage the use of new technologies, new methods, and new excipients that meet product characteristics. It will definitely promote the quality improvement and the secondary development of TCM.
View Article and Find Full Text PDFA temperature-responsive solid-phase microextraction (SPME) coating was prepared via in-situ atom transfer radical polymerization (ATRP) method. By controlling the temperature of solution below and above the lower critical solution temperature (LCST) of the coating, it can switch between hydrophilic and hydrophobic, thus providing a convenient approach for the selective extraction of analytes with different polarities. The average extraction amount of temperature-responsive coating for polar analytes is about 1.
View Article and Find Full Text PDFIn order to assist the refolding of recombinant nitrilase inclusion bodies, a series of thermoresponsive media were prepared by grafting poly(-isopropylacrylamide--butyl-methacrylate) [P(NIPAM--BMA)] brushes onto PS microspheres with various particles and pore sizes an atom transfer radical polymerization (ATRP) method. The effects of particle sizes, pore sizes, and brush grafting amounts of thermoresponsive microspheres on nitrilase refolding were investigated preliminarily. The results showed that the PS-P(NIPAM--BMA) microspheres with the medium particle size (74 μm), gigapore size (320 nm), and high grafting amount (35.
View Article and Find Full Text PDFThree previously undescribed dammarane triterpenoid glycosides () along with five known analogues () were isolated from the leaves of . Their structures and configurations were determined on the basis of comprehensive spectroscopic analyses, chemical hydrolysis and DFT GIAO C NMR calculation. All the isolates were evaluated cytotoxic activities against seven human cancer cell lines (MCF-7, PC-3, Du145, NCI-H1975, PC-9, SKVO3 and HepG2).
View Article and Find Full Text PDFA Gram-stain negative, aerobic, motile, short rod-shaped bacterium, designated as B2.3, was isolated from coal bed water collected from Jincheng, Shanxi Province, China. The strain was able to grow at 10-40 °C (optimum 28-30 °C), pH 4.
View Article and Find Full Text PDFACS Appl Mater Interfaces
April 2017
Natural variations in pH levels of tissues in the body make it an attractive stimuli to trigger drug release from a delivery vehicle. A number of such carriers have been developed but achieving high drug loading combined with low leakage at physiological pH and tunable controlled release at the site of action is an ongoing challenge. Here we report a novel strategy for the synthesis of entirely hydrophilic stimuli-responsive nanocarriers with high passive loading efficiency of doxorubicin (DOX), which show good stability at pH 7 and rapid tunable drug release at intracellular pH.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
April 2017
Commercially available polystyrene (PS) fluorescent microspheres are widely used in biological field for tracing, in vivo imaging and calibration of flow cytometry, among other applications. However, these particles do suffer from some drawbacks such as the leakage and photobleaching of organic dyes within them. In the present study, inherently fluorescent properties of PS based microspheres have been explored for the first time.
View Article and Find Full Text PDFDual thermo- and pH-responsive chromatography has been proposed using poly(N-isopropylacrylamide-co-butyl methacrylate-co-N,N-dimethylaminopropyl acrylamide) (P(NIPAM-co-BMA-co-DMAPAAM)) brushes grafted gigaporous polystyrene microspheres (GPM) as matrix. Atom transfer radical polymerization (ATRP) initiator was first coupled onto GPM through Friedel-Crafts acylation with 2-bromoisobutyryl bromide. The dual-responsive polymer brushes were then grafted onto GPM via surface-initiated ATRP.
View Article and Find Full Text PDFAu@Ag core-shell nanoparticles (NPs) were synthesized and coupled with copper ion (Cu(2+)) for the colorimetric sensing of iodide ion (I(-)). This assay relies on the fact that the absorption spectra and the color of metallic core-shell NPs are sensitive to their chemical ingredient and dimensional core-to-shell ratio. When I(-) was added to the Au@Ag core-shell NPs-Cu(2+) system/solution, Cu(2+) can oxidize I(-) into iodine (I2), which can further oxidize silver shells to form silver iodide (AgI).
View Article and Find Full Text PDFA high-speed thermoresponsive medium was developed by grafting poly(N-isopropylacrylamide-co-butyl methacrylate) (P(NIPAM-co-BMA)) brushes onto gigaporous polystyrene (PS) microspheres via surface-initiated atom transfer radical polymerization (ATRP) technique, which has strong mechanical strength, good chemical stability and high mass transfer rate for biomacromolecules. The gigaporous structure, surface chemical composition, static protein adsorption, and thermoresponsive chromatographic properties of prepared medium (PS-P(NIPAM-co-BMA)) were characterized in detail. Results showed that the PS microspheres were successfully grafted with P(NIPAM-co-BMA) brushes and that the gigaporous structure was robustly maintained.
View Article and Find Full Text PDFGigaporous polystyrene (PS) microspheres were hydrophilized by in situ polymerization to give a stable cross-linked poly(vinyl alcohol) (PVA) hydrogel coating, which can shield proteins from the hydrophobic PS surface underneath. The amination of microspheres (PS-NH2) was first carried out through acetylization, oximation and reduction, and then 4,4'-azobis (4-cyanovaleric acid) (ACV), a polymerization initiator, was covalently immobilized on PS-NH2 through amide bond formation, and the cross-linked poly(vinyl acetate) (PVAc) was prepared by radical polymerization at the surfaces of ACV-immobilized PS microspheres (PS-ACV). Finally, the cross-linked PVA hydrogel coated gigaporous PS microspheres (PS-PVA) was easily achieved through alcoholysis of PVAc.
View Article and Find Full Text PDFA magnetic nano-sized carrier for 10-hydroxycamptothecin (HCPT) was prepared by using Fe(3)O(4) nanoparticles as cores and chitosan (CS) as a polymeric shell by a novel reverse ultrasonic emulsification method. Poly(ethylene glycol) (PEG) chains were then coupled onto the magnetic particles (CS-Fe(3)O(4)) to improve their biocompatibility (PEG-CS-Fe(3)O(4)). HCPT was loaded onto PEG-CS-Fe(3)O(4) by a subtle precipitation method.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
May 2011
Agarose coated gigaporous polystyrene microspheres were evaluated as a novel matrix for immobilized-metal affinity chromatography (IMAC). With four steps, nickel ions were successfully immobilized on the microspheres. The gigaporous structure and chromatographic properties of IMAC medium were characterized.
View Article and Find Full Text PDFAim: Low solubility in water has become an intrinsic property of many anticancer drugs, which poses a hurdle in the translation from the bench to the clinic. In this study, we developed a facile method to prepare 10-hydroxycamptothecin (HCPT) nanocrystallites and testified their feasibility for liver-targeting therapy.
Materials & Methods: HCPT nanocrystallites were prepared under the soft template effect of galactosylated chitosan.
Aim: To investigate the cytotoxic effects of four cyclic bisbibenzyls, Riccardin C (Ric), Pakyonol (Pak), Marchantin M (Mar), and Plagiochin E (Pla) against chemoresistant prostate cancer PC3 cells.
Methods: Cell growth was assayed by MTT method, and apoptotic related protein Bcl-2 and Bax, poly(ADP-ribose) polymerase (PARP) were examined by Western blotting. Cell cycle and apoptosis of PC3 cells were evaluated with flow cytometry and morphologic examinations.
Six macrocyclic bis(bibenzyls) were obtained from the Chinese liverwort Ptagiochasm intermedlum L., and their structures were elucidated as pakyonol (1), neomarchantin A (2), isoriccardin C (3), marchantin H (4), riccardin F (5) and riccardin C (6) on the basis of spectroscopic data and comparison with known compounds. Among them, compounds 3-5 were isolated from this liverwort species for the first time.
View Article and Find Full Text PDFA new trinortriterpenoid, diospyrolide acetate (1) and a new diphenylmethane derivative, pulcherrimumin (12), together with ten known pentacyclic triterpenoids (2-11) and four aromatic compounds (13-16), were isolated from the liverwort Ptilidium pulcherrimum. Their structures were established on the basis of extensive analysis of NMR data and by chemical methods. The cytotoxicity of compounds 1-16 was evaluated against the PC3, MDA-MB-231, and Hela cells lines.
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