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991.
Qin Wang Yanbing Zhao Yajiang Yang Huibi Xu Xiangliang Yang 《Colloid and polymer science》2007,285(5):515-521
In situ gelable poly(N-isopropylacrylamide-co-acrylamide) microgels were prepared by precipitation polymerization in the presence of various amounts
of N,N′-methlenebisacrylamide as a crosslinker. The diameters of microgels were in the range of 200–300 nm with narrow distributions
as determined by photo correlation spectroscopy. The equilibrium swelling ratio and thermosensitive properties of the microgels
increased with decreasing crosslinker content. The volume phase transition of microgels dispersions at high concentrations
were investigated by phase diagrams. The microgels dispersions experienced four phases when the temperature was increased:
semitranslucent swollen gel, clear flowable suspension, cloud flowable suspension, and white shrunken gel. The related phase
transition temperatures were influenced by crosslinker content and the concentration of the microgel dispersions. Herein,
the gelation temperature was changed by more than 20 °C, shrinking temperatures were slightly changed by about 3 °C, and cloud
point temperatures showed almost no change. The three phase transition temperatures of microgels dispersed in phosphate-buffered
saline solutions were lower than that in water. As drug carriers, the release rates of bleomycin from bleomycin-loaded microgel
dispersions exhibited diffusion control at human body temperature. 相似文献
992.
Gisela Buschle-Diller Jared Cooper Zhiwei Xie Ye Wu James Waldrup Xuehong Ren 《Cellulose (London, England)》2007,14(6):553-562
Biocompatible nanofibers that are capable of adapting to the physiological conditions of the human body have become increasingly
important for clinical applications in recent years. Electrospun fiber mats offer particular advantages due to their large
surface area and their sorption/release properties. If loaded with drugs, delivery properties can be tailored to a specific
release rate. This research work focuses on poly(L-lactic acid) (PLA) and poly(ε-caprolactone) (PCL) incorporating three different
model antibiotics as well as bicomponent fibers made from PLA and PCL containing the same model drugs. Tetracycline and chlorotetracycline
hydrochloride, and amphotericin B were selected as model drugs and their release properties and antimicrobial effectiveness
studied. The surface morphology and the average diameter of the fibers strongly depended on the individual spinning system
which in turn influenced the release of the therapeutic compounds from the fibers. Tetracycline was discharged from PCL at
the highest rate while amphotericin B was slowest. PCL almost completely liberated any of the drugs over time while PLA only
released about 10% total. By forming bicomponent PCL–PLA fibers surface and release characteristics could be modified to fit
a sensible drug delivery. 相似文献
993.
This review focuses on possible pitfalls in hair testing procedures. Knowledge of such pitfalls is useful when developing
and validating methods, since it can be used to avoid wrong results as well as wrong interpretations of correct results. In
recent years, remarkable advances in sensitive and specific analytical techniques have enabled the analysis of drugs in alternative
biological specimens such as hair. Modern analytical procedures for the determination of drugs in hair specimens—mainly by
gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–mass spectrometry (LC–MS)—are reviewed and critically
discussed. Many tables containing information related to this topic are provided. 相似文献
994.
Determination of the Anticancer Drug Sorafenib in Serum by Adsorptive Stripping Differential Pulse Voltammetry Using a Chitosan/Multiwall Carbon Nanotube Modified Glassy Carbon Electrode 下载免费PDF全文
Nurgul Karadas‐Bakirhan Stéphanie Patris Sibel A. Ozkan Alp Can Jean‐Michel Kauffmann 《Electroanalysis》2016,28(2):358-365
Adsorptive stripping differential pulse voltammetry (AdSDPV) was applied to the assay of sorafenib in human serum sample. Cyclic voltammetry at a carbon based screen printed electrode (SPE) permitted to detect the irreversible oxidation of SOR with formation of a new compound reversibly oxidized at a lower potential. Quantitative assays were realized using a chitosan/carboxylic acid functionalized multiwalled carbon nanotube modified glassy carbon electrode in 0.1 M phosphate buffer pH 7.0 in the presence of 50 % methanol. The AdSDPV method provided two linear responses within the concentration ranges 1×10?8–8×10?8 M and 1×10?7–8×10?7 M in serum with LOQ and LOD of 3.2×10?9 and 9.6×10?10 of lower linear range, respectively. The recovery of sorafenib in spiked serum was 97.5 %. 相似文献
995.
996.
997.
In this study, the capability of a Layered Double Hydroxide (LDH) to promote the modified-release of Sulindac (Sul), a non-steroid anti-inflammatory drug, was followed by Raman spectroscopy through in vitro and in vivo assays. The drug and the LDH-Sul system were pressed into pellets and their dissolution under controlled conditions was monitored in vitro for 80 h. For the in vivo assays, LDH-drug and LDH-Cl (with chloride in the interlayer space) pellets were implanted between the external and internal oblique muscles of Wistar rats. The pellets were removed after 7, 21, 28 and 35 days from implantation and up to 21 days there was an increase in the amount of intercalated carbonate ions as followed over time by Raman microscopy. The carbonate ions are from the extracellular fluid (conjunctive tissue) and replace the chloride ions between the LDH layers. The same kind of ion exchange was observed for LDH-Sulindac: ca. 50% of the drug was released in vivo after 21 days, whereas in vitro the same amount of drug was delivered within 24 h. The release kinetics was much slower in the in vivo assay due to a significantly smaller hydrodynamic interaction inside the muscle. 相似文献
998.
999.
ChaoCHE ZhongNingZHANG 《中国化学快报》2005,16(4):468-470
Total synthesis of (3Z, 6Z, 9S, 10R)-9, 10-epoxy-3, 6-heneicosadiene, sex pheromone component of Hyphantria cunea (Drug), was achieved using Sharpless AE kinetic resolution and alkylative epoxide rearrangement as key steps. 相似文献
1000.
Two novel polymers containing glucose units as the main-chain that only differ in terms of their regioregularity were synthesized to evaluate their chiral recognition abilities as chiral stationary phases(CSPs)for high performance liquid chromatography(HPLC).The regioregular polymer(poly-5)shows clear resolution ability for the racemate of cobalt(Ⅲ)acetylacetonate(Co(acac)3),whereas the corresponding regioirregular polymer(poly-3)does not show any chiral recognition for Co(acac)3.The regioregular polymer main-chain seems to play an important role not only in providing an efficient interaction with the racemate but also in expressing the chiral recognition ability as a CSP for HPLC. 相似文献