A simple and sensitive high performance liquid chromatography method using fluorescence detection （HPLC- FLD） and a one-step single solvent extraction for the determination of prazosin（PZS） in dog plasma is developed and validated. After extraction with ether, the chromatographic separation of PZS is carried out using a reverse phase C18 column （ 150 mm ×4.6 mm, 5 μm） with a mobile phase of 30% acetonitrile and 70% acetic acid-sodium acetate buffer solution （pH = 3.6） and quantified by fluorescence detection operated with an excitation wavelength of 258 nm and an emission wavelength of 387 nm. The flow rate of the mobile phase is 1.0 mL/min and the retention time of PZS and the internal standard is found to be 4. 4 and 5. 8 rain, respectively. The calibration curve is linear within a concentration range from 1.0 to 1 000.0 ng/mL （ P 〉 0. 998）. The limit of detection is 0.4 ng/mL. The inter-day coefficient of variation （COV） of the calibration standards is below 5.0% and the mean accuracy is in the range from 92. 7% to 104. 2%. Moreover, by analyzing quality control plasma samples for three days, the results show that the method is precise and accurate, for the intra- and inter- day COV within 10% and the accuracy from 95.9% to 112.7%. The developed and validated method is successfully applied to phannacokinetic study for the preclinical evaluation of a new peroral PZS-sulfobutyl ether beta-cyclodextrin （PZS-SBE-β-CD） inclusion complex tablets （test preparation）, which demonstrates that the test preparation released PZS is conducted in a slow and controlled way, and the relative bioavailability of the test preparation is found to be 105.0%.
Galactosylated chitosan （GC） is synthesized and used to prepare IL-1Ra loaded GC nanoparticles by an electrospraying technique. Polyethylene oxide （PEO） is mixed with GC to enhance the electrospraying ability. The effect of the spraying solution properties on particle formation is investigated. The IL-1Ra loaded nanoparticles with an average diameter of 530 nm and a regularly spherical shape are observed by the scanning electron microscopy （SEM）. The amount of the IL-1Ra is measured by the enzyme-linked immunosorbent assay （ELISA） kit. The loading capacity of the nanoparticle is （1.52± 0.04）% （n = 3） and the encapsulation efficiency reaches （90. 36 ± 3.46） % （n = 3）. For the evaluation of GC nanoparticles＇ hepatocytes targeting efficacy, hepatocytes and mesenchymal stem cells （MSCs） are incubated with FITC-labeled GC nanoparticles for 24 h as the experimental and control groups. Results of the fluorescence microscope show that the fluorescence signals observed in hepatocytes are significantly higher than in the MSCs, indicating that the developed GC nanoparticles have an obvious liver targeting property.
