Molecular imprinting technique (MIT) involves the synthesis of polymer in the presence of a template to produce complementary binding sites in terms of its size, shape, and functional group orientation. Such kind of polymer possesses specific recognition ability towards its template molecule. Despite the rapid development of MIT over the years, the majority of the template molecules that have been studied are small molecules, while molecular imprinting of proteins remains a significant yet challenging task due to their large size, structural flexibility and complex conformation. In this review, we summarize the research findings over the past five years, and discuss the characteristics of the technique, the most recent progress and the perspective in the field of molecular imprinting of proteins.
Epitopes ; chemistry ; Molecular Imprinting ; methods ; trends ; Nanoparticles ; chemistry ; Polymers ; chemistry ; Proteins ; chemistry

In the structural determination of natural glycosides, nuclear magnetic resonance (NMR) is an important approach in determining the configuration of glycoside bond. The test of coupling constant of the anomeric proton and chemical shift of the anomeric carbon are two common methods, but these methods are not suitable for some sugars. For those sugars, detailed 13C NMR analysis is an alternative choice. This paper summarizes the characteristics of 1H and 13C NMR data of the common monosaccharides published in the literatures, in order to search an approach to determine the configuration of glycoside bond.
Carbohydrate Conformation ; Carbon Isotopes ; Glycosides ; chemistry ; Magnetic Resonance Spectroscopy ; methods ; Monosaccharides ; chemistry

With the development of stem cells and regenerative medicine (treatment of various diseases using stem cells) research, the induction of differentiation of human stem cell technology has also made significant progress. The development of chemical biology offers a variety of small biological molecules for stem cell biology. This review focuses on how small molecule compounds (natural and synthetic) induce differentiation of stem cells.
Animals ; Cell Differentiation ; drug effects ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Embryonic Stem Cells ; cytology ; High-Throughput Screening Assays ; methods ; Humans ; Plants, Medicinal ; chemistry ; Regenerative Medicine ; trends ; Signal Transduction ; Small Molecule Libraries ; chemistry ; pharmacology ; Stem Cells ; cytology ; Wnt Proteins ; metabolism

The purpose of the present study is to use beta-cyclodextrin polymers (beta-CDP) with different cross-linked degree (CLD) to form inclusion complexes with ibuprofen and examine the effects of structural and compositional factors of beta-CDP on its drug loading and release behaviors. A series of beta-CDP with different CLD were synthesized and characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and 13C NMR spectrum. The beta-CDP was systemically characterized for the relation between the CLD of beta-CDP and the drug loading and release as well. The results of FT-IR and 13C NMR showed that similar peak-shaped vibration of beta-CDP and beta-CD implies that the polymer keeps the original characteristic structure of beta-CD. The CLD of the beta-CDP played a critical role in the drug loading and release, increasing the CLD resulted in reduction of drug loading, but increase in drug release.
Carbon Isotopes ; Cross-Linking Reagents ; chemistry ; Delayed-Action Preparations ; Drug Carriers ; Drug Compounding ; Drug Delivery Systems ; Ibuprofen ; administration & dosage ; chemistry ; Magnetic Resonance Spectroscopy ; Pharmaceutical Preparations ; administration & dosage ; chemistry ; Polymers ; chemistry ; Solubility ; Spectroscopy, Fourier Transform Infrared ; beta-Cyclodextrins ; chemistry

Fragmentation behavior of diterpenoids was investigated by ESI/MSn and the qualitative analysis of diterpenoids in the bark of Pseudolarix kaempferi was performed using high-performance liquid chromatography/ multi-stage mass spectrometry (HPLC-ESI/MSn). The characteristic fragmentation behaviors of the diterpenoids are the cleavages of the lactone ring and C4-O bond. Furthermore, the eliminations of substituent groups at C-18, C-7 and C-8 can also be observed in the MS" (n = 3-4) spectra. For C-4 acetoxy subsititued diterpenoids, [M+Na-60]+ and [M-H-104] are the base peaks of MS2 spectra in the positive and negative ionization modes, respectively. For C-4 hydroxyl subsititued diterpenoids, [M+Na-44]+ and [M-H-62] are the base peaks of MS2 in the positive and negative ionization modes, respectively. For C-18 glucosylated or esterized diterpenoids, [M+Na-44]+ is the base peak of MS2 spectra in positive ionization mode. These fragmentation rules were successfully exploited in the identification of diterpenoids in methanol/water (6:4) extract of P. kaempferi by LC-MS in positive ionization mode. A total of 9 diterpenoids were identified or tentatively characterized, and one of them is reported here for the first time. The described method could be utilized for the sensitive and rapid qualitative analysis of P. kaempferi.
Chromatography, High Pressure Liquid ; methods ; Diterpenes ; analysis ; chemistry ; isolation & purification ; Drugs, Chinese Herbal ; analysis ; chemistry ; isolation & purification ; Molecular Structure ; Pinaceae ; chemistry ; Plant Bark ; chemistry ; Plants, Medicinal ; chemistry ; Spectrometry, Mass, Electrospray Ionization ; Tandem Mass Spectrometry

To investigate the chemical constituents in the stems of Chirita longgangensis var. hongyao, methanol extract of the stems was subjected to column chromatography with various chromatographic techniques. One new beta-naphthalenecarboxylic acid biglycoside, 1, 4-dihydroxy-2-naphthalenecarboxylic acid methyl ester-4-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (1) was isolated, along with two known compounds: isotaxiresinol 4-O-methyl ether (2) and (R)-7-hydroxy-alpha-dunnione (3). Compound 2 was first obtained from Chirita genus and compound 3 was isolated from this plant for the first time. All structures were elucidated on the basis of spectral and chemical evidence, and the NMR spectroscopic data of compound 2 was published for the first time.
Glucosides ; chemistry ; isolation & purification ; Magnoliopsida ; chemistry ; Molecular Structure ; Naphthalenes ; chemistry ; isolation & purification ; Plant Stems ; chemistry ; Plants, Medicinal ; chemistry

In this study, polyelectrolyte microcapsules have been fabricated by biocompatible ferrosoferric oxide nanoparticles (Fe3O4 NPs) and poly allyamine hydrochloride (PAH) using layer by layer assembly technique. The Fe3O4 NPs were prepared by chemical co-precipitation, and characterized by transmission electron microscopy (TEM) and infrared spectrum (IR). Quartz cell also was used as a substrate for building multilayer films to evaluate the capability of forming planar film. The result showed that Fe3O4 NPs were selectively deposited on the surface of quartz cell. Microcapsules containing Fe3O4 NPs were fabricated by Fe3O4 NPs and PAH alternately self-assembly on calcium carbonate microparticles firstly, then 0.2 molL(-1) EDTA was used to remove the calcium carbonate. Scanning electron microscopy (SEM), Zetasizer and vibrating sample magnetometer (VSM) were used to characterize the microcapsule's morphology, size and magnetic properties. The result revealed that Fe3O4 NPs and PAH were successfully deposited on the surface of CaCO3 microparticles, the microcapsule manifested superparamagnetism, size and saturation magnetization were 4.9 +/- 1.2 microm and 8.94 emu x g(-1), respectively. As a model drug, Rhodamin B isothiocyanate labeled bovine serum albumin (RBITC-BSA) was encapsulated in microcapsule depended on pH sensitive of the microcapsule film. When pH 5.0, drug add in was 2 mg, the encapsulation efficiency was (86.08 +/- 3.36) % and the drug loading was 8.01 +/- 0.30 mg x m(L-1).
Calcium Carbonate ; chemistry ; Capsules ; Chemical Precipitation ; Drug Carriers ; Drug Compounding ; methods ; Drug Delivery Systems ; Electrolytes ; chemistry ; Ferrosoferric Oxide ; chemistry ; Magnetite Nanoparticles ; Microscopy, Electron, Scanning ; Microscopy, Fluorescence ; Particle Size ; Rhodamines ; administration & dosage ; chemistry ; Serum Albumin, Bovine ; administration & dosage ; chemistry

The purpose of this study is to design push-pull osmotic pump (PPOP) tablets of famotidine using the expert system for the formulation design of osmotic pump of poor water-soluble drug which had been established by the authors. Firstly, the parameters which were requisite of the system input were obtained from literatures and experimental tests. Then the parameters were input into the system, and the program was run. The system displayed the designed formulations sequential. Finally, famotidine PPOP was prepared according to the designed formulations and the in vitro dissolution was carried out. It was found out that the target formulation of famotidine PPOP which could release for 24 hours was obtained in a very short period. Meanwhile, the practicability of the established expert system was proved.
Delayed-Action Preparations ; Drug Delivery Systems ; methods ; Excipients ; chemistry ; Expert Systems ; Famotidine ; administration & dosage ; chemistry ; Osmosis ; Solubility ; Tablets ; Water

Polyamidoamine-polyethylene glycol (PAMAM-PEG) copolymers were synthesized using IPDI as coupling reagent by two-step method. The copolymers were characterized by IR spectrum and 1H NMR spectrum, and the PEG conjugating ratios of the copolymers were calculated equal to 10% and 30% separately. MTT assay indicated that after PEGylation a lower cytotoxicity of the copolymers could be found, and with increasing PEG conjugating ratio the cytotoxicity decreased obviously. Agarose gel retardation assay demonstrated that PAMAM-PEG copolymers could be combined with DNA and PAMAM-PEG/DNA complexes were prepared by self-assembly. DLS measurement showed that when N/P > or = 50, the particle size of copolymer/ gene complexes was in a range of 150-200 nm, and the zeta potential was in a range of 10-25 mV. In vitro gene transfection illustrated that when N/P < or = 50, the gene transfection efficiency of PAMAM-PEG copolymers was a little less than that of PAMAM-G5, but the transfection efficiency can be raised by increasing N/P ratio or transfection time. Considering both cytotoxicity and transfection efficiency aspects PAMAM-PEG-13 was more effect than PAMAM-PEG-39 in PEGylation.
Carcinoma, Hepatocellular ; pathology ; Cell Line, Tumor ; Cell Survival ; drug effects ; DNA ; chemistry ; pharmacology ; Dendrimers ; chemical synthesis ; pharmacology ; Gene Transfer Techniques ; Genetic Vectors ; Humans ; Isocyanates ; chemistry ; Liver Neoplasms ; pathology ; Particle Size ; Polyamines ; chemistry ; Polyethylene Glycols ; chemical synthesis ; chemistry ; pharmacology ; Transfection

This study is to prepare the pantoprazole sodium enteric-coated tablet which is compacted by pellets. The enteric-coated pantoprazole sodium pellets were prepared by fluid bed coating technology. The pantoprazole sodium enteric-coated tablets were prepared by direct compression of the enteric-coated pellets and suitable excipients. In vitro dissolution method and scanning electron microscope method were used for the observation of the drug release behavior before and after compression of the pellets. The optimized formulation is: the coating level is 55%, the plasticizer content is 20%, the ratio of Eudragit L30D-55/NE30D is 8 : 2, enteric-coated pellets/excipients (MCC/PPVP/PEG 6000 = 2 : 1 : 1) is 5 : 5, the enteric-coated tablets release in artificial gastric fluid in 2 h is less than 10%, while in artificial intestinal fluid in 1 h is more than 85%. The release behavior of pantoprazole sodium enteric-coated pellets-type tablet is quite well. And it may be used in industrial production.
2-Pyridinylmethylsulfinylbenzimidazoles ; administration & dosage ; chemistry ; Chromatography, High Pressure Liquid ; methods ; Drug Carriers ; Drug Compounding ; methods ; Excipients ; Microscopy, Electron, Scanning ; Plasticizers ; chemistry ; Polyethylene Glycols ; chemistry ; Polymethacrylic Acids ; chemistry ; Proton Pump Inhibitors ; administration & dosage ; chemistry ; Solubility ; Tablets, Enteric-Coated ; chemistry ; Technology, Pharmaceutical