Nanostructured lipid carrier based topical gel of Ganoderma Triterpenoids for frostbite treatment / 中国天然药物

The objective of this study was to prepare nanostructured lipid carrier (NLC)-based topical gel of Ganoderma Triterpenoids (GTs) and evaluate their effects on frostbite treatment. GT-NLCs was prepared by the high pressure homogenization method and then characterized by morphology and analyses of particle size, zeta potential, entrapment efficiency (EE), and drug loading (DL). The NLCs was suitably gelled for skin permeation studies in vitro and pharmacodynamic evaluation in vivo, compared with the GT emulgel. The GT-NLC remained within the colloidal range and was uniformly dispersed after suitably gelled by carbopol preparation. Transmission electron microscopy (TEM) study showed GT-NLCs was spherical in shape. The EE (%) and DL (%) could reach up to (81.84 ± 0.60)% and (2.13 ± 0.12)%, respectively. The result of X-ray diffractograms (XRD) showed that GTs were in an amorphous state in the NLC-gel. In vitro permeation studies through rat skin indicated that the amount of GTs permeated through skin of GT-NLCs after 24 h was higher than that of GT emulsion, and GT-NLCs increased the accumulative amounts of GTs in epidermis 7.76 times greater than GT emulsion. GT-NLC-gel was found to possess superior therapeutic effect for frostbite, compared with the GT emulgel. The NLC based topical gel of GTs could improve -their therapeutic effect for frostbite.

Mixed nanomicelles loaded with thymopeptides-sodium deoxycholate/phospholipid improve drug absorption / 中国天然药物

AIM@#To improve the absorption of thymopeptides (TH) by preparing sodium deoxycholate/phospholipid-mixed nanomicelles (SDC/PL-MMs).@*METHODS@#TH-SDC/PL-MMs were prepared by a film dispersion method, and then evaluated using photon correlation spectroscopy (PCS), zeta potential measurement, as well as their physical stability after storage for several days. Furthermore, in situ intestinal single-pass perfusion experiments and pharmacodynamics in immunodeficient mice were performed to make a comparison with TH powders and the control drug in absorption properties.@*RESULTS@#A narrow size distribution of nanomicelles, with a mean particle size of (149 ± 8.32) nm and a zeta potential of (-31.05 ± 2.52) mV, was obtained. The in situ intestine perfusion experiments demonstrated a significant advantage in absorption characteristics for TH compared to the other formulations, and oral administration of TH-SDC/PL-MMs potentiated an equivalent effect with i.h. TH in pharmacodynamic studies in immunodeficient mice.@*CONCLUSIONS@#TH-SDC/PL-MMs prepared by a film dispersion method are able to improve the absorption of TH. SDC/PL-MMs might be a good approach for the more effective delivery of drugs like TH.

Characterization and evaluation in vivo of baicalin-nanocrystals prepared by an ultrasonic-homogenization-fluid bed drying method / 中国天然药物

AIM@#To improve the absorption and bioavailability of baicalin using a nanocrystal (or nanosuspension) drug delivery system.@*METHODS@#A tandem, ultrasonic-homogenization-fluid bed drying technology was applied to prepare baicalin-nanocrystal dried powders, and the physicochemical properties of baicalin-nanocrystals were characterized by scanning electron microscopy, photon correlation spectroscopy, powder X-ray diffraction, physical stability, and solubility experiments. Furthermore, in situ intestine single-pass perfusion experiments and pharmacokinetics in rats were performed to make a comparison between the microcrystals of baicalin and pure baicalin in their absorption properties and bioavailability in vivo.@*RESULTS@#The mean particle size of baicalin-nanocrystals was 236 nm, with a polydispersity index of 0.173, and a zeta potential value of -34.8 mV, which provided a guarantee for the stability of the reconstituted nanosuspension. X-Ray diffraction results indicated that the crystallinity of baicalin was decreased through the ultrasonic-homogenization process. Physical stability experiments showed that the prepared baicalin-nanocrystals were sufficiently stable. It was shown that the solubility of baicalin in the form of nanocrystals, at 495 μg·mL(-1), was much higher than the baicalin-microcrystals and the physical mixture (135 and 86.4 μg·mL(-1), respectively). In situ intestine perfusion experiments demonstrated a clear advantage in the dissolution and absorption characteristics for baicalin-nanocrystals compared to the other formulations. In addition, after oral administration to rats, the particle size decrease from the micron to nanometer range exhibited much higher in vivo bioavailability (with the AUC(0-t) value of 206.96 ± 21.23 and 127.95 ± 14.41 mg·L(-1)·h(-1), respectively).@*CONCLUSION@#The nanocrystal drug delivery system using an ultrasonic-homogenization-fluid bed drying process is able to improve the absorption and in vivo bioavailability of baicalin, compared with pure baicalin coarse powder and micronized baicalin.

Comparison of anti-bacterial activity of three types of di-O-caffeoylquinic acids in Lonicera japonica flowers based on microcalorimetry / 中国天然药物

The anti-bacterial activities of three types of di-O-caffeoylquinic acids (diCQAs) in Lonicera japonica flowers, a traditional Chinese medicine (TCM), on Bacillus shigae growth were investigated and compared by microcalorimetry. The three types of diCQAs were 3, 4-di-O-caffeoylquinic acid (3, 4-diCQA), 3, 5-di-O-caffeoylquinic acid (3, 5-diCQA), and 4, 5-di-O-caffeoylquinic acid (4, 5-diCQA). Some qualitative and quantitative information of the effects of the three diCQAs on metabolic power-time curves, growth rate constant k, maximum heat-output power Pm, and the generation time tG, total heat output Qt, and growth inhibitory ratio I of B. shigae were calculated. In accordance with a thermo-kinetic model, the corresponding quantitative relationships of k, Pm, Qt, I and c were established. Also, the half-inhibitory concentrations of the drugs (IC50) were obtained by quantitative analysis. Based on the quantity-activity relationships and the IC50 values, the sequence of inhibitory activity was 3, 5-diCQA > 4, 5-diCQA > 3, 4-diCQA. The results illustrate the possibility that the caffeoyl ester group at C-5 is the principal group that has a higher affinity for the bacterial cell, and that the intramolecular distance of the two caffeoyl ester groups also has an important influence on the anti-bacterial activities of the diCQAs.

Preparation of baicalin nanocrystal pellets and preliminary study on its pharmacokinetics / 中国中药杂志

<p><b>OBJECTIVE</b>To prepare baicalin nanocrystal (BC-NC) and evaluate its pharmacokinetics in rats.</p><p><b>METHOD</b>Baicalin nanosuspensions (BC-NS) were prepared by the high pressure homogenization technology combined with ultrasonic, and then BC-NS were solidificated into BC-NC pellets by removing the water through fluid-bed drying. Its morphology, mean diameter and Zeta-potential were determined. An HPLC method was employed to determine the concentration of baicalin in plasma, and the bioavailability of the nanocrystal was compared with the reference group by oral administration in Wistar rats.</p><p><b>RESULT</b>The nanocrystals observed by scanning electron microscopy were irregular granulated, and the mean particle sizes of BC-NC were (248 +/- 6) nm. Its polydispersity index (PI) and zeta-potential were (0.181 +/- 0.065), (-32.3 +/- 1.8) mV, respectively. The pharmacokinetic parameters showed that the C(max) was (16.54 +/- 1.73) mg x L(-1) and the AUC(0-24 h) was (206.96 +/- 21.23) mg x L(-1) x h, which were significantly enhanced compared with the baicalin bulk and baicalin physical mixture (BC-PM) formulation, respectively (P < 0.01).</p><p><b>CONCLUSION</b>Baicalin nanocrystal can significantly improve the bioavailability of baicalin.</p>