A novel oral delivery system that TPGS modified docetaxel proniosomes, DTX-TPGS-PN, was developed and the characterization after hydration was observed. Firstly, Doce-TPGS-PN was optimized by investing the factors, including the type of surfactant, methods of adding TPGS, content of TPGS and the molar ratio of span40/cholesterol, which may affecting the particle size, encapsulation efficiency and instantaneous release of drug in the formulation. Then, the morphology, particle size, Zeta potential, encapsulation efficiency and in vitro release of the formulation were evaluated. The result showed that hydrated nanoparticles of DTX-TPGS-PNs were (93 ± 6.5) nm in size,(-83.95 ± 3.69) mV in zeta potential, (97.31 ± 0.60)% in encapsulation efficiency, exhibiting spherical morphology and biphasic release process that a low burst effect within the first 0.5 hour and a relative-sustained release for the next several hours in PBS. These results indicate the oral delivery system of DTX-TPGS-PN was successfully built with good properties.
Chemistry, Pharmaceutical ; methods ; Particle Size ; Polyethylene Glycols ; chemistry ; Taxoids ; chemistry ; pharmacology ; Vitamin E ; analogs & derivatives ; chemistry

This paper aims to raise concerns about the modification of bovine hemoglobin with the use of SC-mPEG as modifying reagent. The yield rates of SC-mPEG-BHB under dissimilar conditions are studied, and more important, a series of methods used to characterize the SC-mPEG-BHB mixtures are built. The best reactive system has been confirmed, i.e., at 4 degrees C, pH9; SC-mPEG and BHB are mixed according to the proportion of 60:1 and be submitted to reaction for 2 h.
Animals ; Blood Substitutes ; chemical synthesis ; Cattle ; Hemoglobins ; chemistry ; classification ; pharmacology ; Humans ; Hydrogen-Ion Concentration ; Polyethylene Glycols ; chemistry ; classification

OBJECTIVETo formulate gentamicin liposphere by solvent-melting method using lipids and polyethylene glycol 4 000 (PEG-4 000) for oral administration.

METHODSGentamicin lipospheres were prepared by melt-emulsification using 30% w/w Phospholipon® 90H in Beeswax as the lipid matrix containing PEG-4 000. These lipospheres were characterized by evaluating on encapsulation efficiency, loading capacity, change in pH and the release profile. Antimicrobial activities were evaluated against Escherichia coli, Pseudomonas aeruginosa, Salmonella paratyphii and Staphylococcus aureus using the agar diffusion method.

RESULTSPhotomicrographs revealed spherical particles within a micrometer range with minimal growth after 1 month. The release of gentamicin in vitro varied widely with the PEG-4 000 contents. Moreover, significant (P>0.05) amount of gentamicin was released in vivo from the formulation. The encapsulation and loading capacity were all high, indicating the ability of the lipids to take up the drug. The antimicrobial activities were very high especially against Pseudomonas compare to other test organisms. This strongly suggested that the formulation retain its bioactive characteristics.

CONCLUSIONSThis study strongly suggest that the issue of gentamicin stability and poor absorption in oral formulation could be adequately addressed by tactical engineering of lipid drug delivery systems such as lipospheres.

Anti-Bacterial Agents ; chemistry ; pharmacokinetics ; pharmacology ; Bacteria ; drug effects ; Gentamicins ; chemistry ; pharmacokinetics ; pharmacology ; Liposomes ; chemistry ; Microbial Sensitivity Tests ; Particle Size ; Phosphatidylcholines ; chemistry ; Polyethylene Glycols ; chemistry

Environmental stimuli-sensitive biodegradable drug delivery systems are drawing more and more attentions because of their advantages such as smart properties, high efficiency and easy-to-handle properties. On the basis of a large quantity of references on this topic, a review has been made on the developments of the thermosensitive and pH-sensitive intelligent polymeric systems for drug delivery.
Biocompatible Materials ; chemistry ; pharmacology ; Biodegradation, Environmental ; Chitosan ; chemistry ; Delayed-Action Preparations ; Drug Delivery Systems ; Excipients ; chemistry ; Humans ; Polyethylene Glycols ; chemistry ; Polyglactin 910 ; chemistry

Hydroxypropyl methylcellulose (HPMC) propels self-emulsifying drug delivery systems (SEDDS) to achieve the supersaturated state in gastrointestinal tract, which possesses important significance to enhance oral absorption for poorly water-soluble drugs. This study investigated capacities and mechanisms of HPMC with different viscosities (K4M, K15M and K100M) to inhibit drug precipitation of SEDDS in the simulated gastrointestinal tract environment in vitro. The results showed that HPMC inhibited drug precipitation during the dispersion of SEDDS under gastric conditions by inhibiting the formation of crystal nucleus and the growth of crystals. HPMC had evident effects on the rate of SEDDS lipolysis and benefited the distribution of drug molecules across into the aqueous phase and the decrease of drug sediment. The mechanisms were related to the formed network of HPMC and its viscosities and molecular weight. These results offered a reference for selecting appropriate type of HPMC as the precipitation inhibitor of supersaturatable SEDDS.
Caprylates ; chemistry ; Chemical Precipitation ; drug effects ; Crystallization ; Drug Delivery Systems ; methods ; Emulsifying Agents ; chemistry ; Emulsions ; Ethylene Glycols ; chemistry ; Glycerides ; chemistry ; Hypromellose Derivatives ; administration & dosage ; chemistry ; pharmacology ; Indomethacin ; administration & dosage ; chemistry ; Lipolysis ; drug effects ; Molecular Weight ; Polyethylene Glycols ; chemistry ; Viscosity

AIMTo study unitary-core osmotic pump tablet for delivering water-insoluble drug for 24 hours.

METHODSUnitary-core osmotic pump tablet was prepared using nifedipine as the model drug. The effects of various core formulation variables on drug release were studied.

RESULTSPolyethylene oxide and potassium chloride have comparable positive effects on drug release, whereas, nifedipine has markedly negative effect on drug release.

CONCLUSIONUnitary-core osmotic pump tablet is very easy in preparation and it can deliver water-insoluble drug in substantially constant rate for 24 hours.

Calcium Channel Blockers ; administration & dosage ; chemistry ; Delayed-Action Preparations ; Drug Delivery Systems ; Nifedipine ; administration & dosage ; chemistry ; Osmosis ; Polyethylene Glycols ; pharmacology ; Potassium Chloride ; pharmacology ; Solubility ; Tablets ; Technology, Pharmaceutical ; methods

To improve the physical property and bioactivity of methotrexate, this paper investigated the new formation of conjugate methotrexate-poly (ethylene glycol) and in vitro anti-tumor activity of the synthesized conjugate. The conjugate of methotrexate-poly (ethylene glycol), which was verified by the spectroscopy analysis of UV, IR and 13C NMR, was synthesized by chemical catalysis and micro-wave irritation. The determination for the conjugate of solubility in water and distribution coefficient in octanol-water system of the conjugate was done to examine its deliquescence property. The solubility in water and the distribution coefficient of the conjugate was greatly improved, which was increased by 128 folds and 5 folds, respectively. The in vitro anti-tumor activity of the conjugate was tested by mouse L(1210) leukaemia cells, and the synthesized conjugate showed the same anti-tumor activity as the original methotrexate. Compared to the reported literature, the modification of methotrexate by poly (ethylene glycol) is more rapid and convenient.
Animals ; Antineoplastic Agents ; chemical synthesis ; Leukemia L1210 ; drug therapy ; Methotrexate ; chemical synthesis ; chemistry ; pharmacology ; Mice ; Polyethylene Glycols ; chemical synthesis ; chemistry ; pharmacology ; Solubility

OBJECTIVEThrough observing the morphology and topography of the prepared influenza viruses (H1N1) treated with the different Nonidet P-40 solutions using atomic force microscopy (AFM), to explore the application of AFM on the research of the internal character of viral morphology and structural virology.

METHODSThe virus samples were treated with serial diluted Nonidet P-40 solutions from 0.05% to 0.20% and then investigated by AFM with the tapping mode in air at room temperature to obtain the morphology and topography changes including height data,amplitude data and phase data for both spherical and filamentous influenza virus A.

RESULTSThe serial AFM images show that the erosion degree of the virions is proportional with the improvement of NP-40 concentration,and partly denuded virion image appeared at 0.05% NP-40 treatment, which was revealed clearly on both amplitude images and phase images.

CONCLUSIONThis work demonstrated for the first time that the internal topography of influenza virion could be revealed by AFM via suitable nonionic surfactants chemical dissection.

Humans ; Influenza A virus ; chemistry ; drug effects ; Microscopy, Atomic Force ; instrumentation ; Nanostructures ; Orthomyxoviridae ; chemistry ; drug effects ; Polyethylene Glycols ; pharmacology ; Spermatocidal Agents ; pharmacology

To synthetize 3-carboxypropyl-triphenylphosponium bromide-polycaprolacton-CTPP-PEG-PC, and prepare curcumin CTPP-PEG-PCL micelles by using the self-assembled emulsion solvent evaporation method, in order to determine the critical micelle concentration (CMC) with the pyrene fluorescent probe technology, detect the particle size, entrapment efficiency (%), morpheme and in vitro release rate, and evaluate the cytotoxicity of hepatic stellate cells with MTT assay. The structure of CTPP-PEG-PCL had been identified by 1H-NMR spectra. Specifically, the CMC of polymer was 2.25 mg x L(-1), the average size was 190 nm, the drug content was (0.66 +/- 0.008) g x L(-1), and the entrapment efficiency was (94 +/- 0.6)%. The in vitro release results showed curcumin micelles had a significant higher inhibition ratio in the growth of hepatic stellate cells than crude curcumin (P < 0.05). This suggested that CTPP-PEG-PCL micelles feature low CMC, high encapsulation efficiency and notable inhibition effect in growth of hepatic stellate cells.
Cell Line ; Cell Proliferation ; drug effects ; Curcumin ; administration & dosage ; chemistry ; pharmacology ; Hepatic Stellate Cells ; drug effects ; Micelles ; Polyesters ; administration & dosage ; chemistry ; Polyethylene Glycols ; administration & dosage ; chemistry

OBJECTIVETo study the optimum conditions of simulated drought stress, and screen the indexes of drought resistance and comprehensively assess the drought resistance of the Angelica dahurica resources during seedling stage.

METHODInvestigations were carried out on the changes of height, root length, root-shoot ration, contents of soluble sugar, proline and malondialdehyde under polyethylene glycol (PEG-6000)-simulated drought stress. A comprehensive evaluation on the drought resistance of different (varietal) species of A. dahurica during seedling stage was applied by using the method of subordinate function. And the drought resistance indexes were selected out by applying the method of grey correlative degree analysis.

RESULTDrought stress of 9 days with 20% PEG was the optimum condition for the simulation of drought stress. The results showed that the drought resistant capability decreased in the order as follows, A. dahurica from Sichuan province, A. dahurica from Henan province, A. dahurica from Hebei province and A. dahurica from Zhejiang province. And the order of correlative degree of drought resistance and indexes was: soluble sugar > root length > proline > root-shoot ration > total content of chlorophyll > chlorophyll b > chlorophyll a > height > malondialdehyde.

CONCLUSIONOsmotic adjustment substance and the indexes related to the root have more influence on the drought resistance of A. dahurica during seedling stage. A. dahurica from Sichuan province shows the highest drought resistance during seedling stage.

Angelica ; chemistry ; drug effects ; physiology ; Droughts ; Plant Extracts ; analysis ; Polyethylene Glycols ; pharmacology ; Seedlings ; chemistry ; drug effects ; physiology ; Stress, Physiological ; drug effects