Pharmacokinetic study on dry powder inhalation administration of α-asarone in rats / 中国中药杂志

To study the pharmacokinetic characteristics and absolute bioavailability of α-asarone through dry powder inhalation in rats, and compare with that through oral administration and intravenous injection. A HPLC method was established for the determination of α-asarone in rat plasma to detect the changes in plasma concentrations of α-asarone through dry powder inhalation (20 mg · kg(-1)), oral administration (80 mg · kg(-1)) and intravenous injection (20 mg · kg(-1)) in rats. DAS 2.0 software was used to calculate the pharmacokinetic parameters. The absolute bioavailability of α-asarone was calculated according to AUC(0-t)) of administration routes and administration doses. According to the results, α-asarone showed good linear relations (r = 0. 999 4) at concentrations between 0.282-14.1 mg · L(-1), with the limit of detection (LOD) at 0.212 mg · L(-1). Through dry powder inhalation, oral administration and intravenous injection of α-asarone, the metabolic processes of α-asarone in rats conformed to one, two and three compartment models respectively, with the elimination half-life of (95.48 ± 48.28), (64.34 ± 27.59), (66.99 ± 29.76) min. According to the bioavailability formula, the absolute bioavailability of α-asarone through dry powder inhalation and oral administration were 78.32% and 33. 60%, respectively. This study showed that significant increase in elimination half-life and absolute bioavailability of α-asarone through dry powder inhalation, which lays a theoretical foundation for preparing α-asarone dry powder inhalers.

Preparation and characterization of tetrandrine-loaded PLGA nanocomposite particles by premix membrane emulsification coupled with spray-drying method / 药学学报

For effective inhalable dry-powder drug delivery, tetrandrine-PLGA (polylactic-co-glycolic acid) nanocomposite particles have been developed to overcome the disadvantages of nanoparticles and microparticles. The primary nanoparticles were prepared by using premix membrane emulsification method. To prepare second particles, they were spray dried. The final particles were characterized by scanning electron microscopy (SEM), dry laser particle size analysis, high performance liquid chromatography (HPLC), X-ray diffraction (XRD), differential scanning calorimetry (DSC), infrared analysis (IR) and confocal laser scanning microscope (CLSM). The average size of the primary particles was (337.5 ± 6.2) nm, while that second particles was (3.675 ± 0.16) μm which can be decomposed into primary nanoparticles in water. And the second particles were solid sphere-like with the drug dispersed as armorphous form in them. It is a reference for components delivery to lung in a new form.

In vitro and in vivo study of fluorescent probe PLGA particles prepared by premix membrane emulsification method / 中国中药杂志

Relatively uniform-sized nanoparticles made of poly (lactic-co-glycolic acid) (PLGA) were prepared by premix membrane emulsification method. After the drug loading property was completed, the dynamic tissue distribution of nanoparticles was recorded. With the average particle size and span as indexes, membrane pore size, number of passing membrane times, membrane pressure, volume ratio of oil-water phase and the concentration of poly(vinyl alcohol) (PVA) in external water phase were investigated by single factor test, the optimum preparation technology of blank PLGA nanlparticles was as following: pore size of SPG membrane was 1 μm, membrane pressure was 1. 15 MPa, the number of passing membrane time was 3, the mass fraction of PVA of 2%, volume ratio of oil-water phase of 1 : 5. Prepared nanoparticles were round with smooth surface, the mean diameter was 332.6 nm, span was 0.010, the confocal laser scanning microscope (CLSM) concluded that fluorescent substance is uniform composizion in PLGA nanoparticle, and the in vivo imaging technology in mice include that the nanoparticles show good liver and spleen targeting property.