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In order to prepare angiopep-2 modified fluorescein isothiocyanate-labeled neurotoxin nanoparticles( ANG-NPs/FITCNT),emulsion/solvent evaporation method was used with m PEG-PLA and ANG-PEG-PLA( in proper proportions) as carriers and with FITC-NT as drug. With particle size and encapsulation efficiency as comprehensive indexes,the effects of different ultrasound power and ultrasound time combinations on the process were investigated. The in vitro release characteristics of nanoparticles in PBS buffer at p H 7. 4 and p H 6. 5 were investigated by dialysis method. The results indicated that the optimum process for preparing ANG-NPs/FITC-NT was as follows: ultrasonic power 90 W,ultrasonic time 30 s. In such optimal process,ANG-NPs/FITC-NT were well-shaped under the transmission electron microscope,with an average particle size of( 123. 9±0. 5) nm,Zeta potential of(-10. 5±0. 5) m V,encapsulation efficiency of( 68. 1±0. 4) %,and the drug loading of( 0. 82±0. 01) %. The in vitro drug release profiles of the nanoparticles in PBS buffer at p H 7. 4 and p H 6. 5 were both consistent with Ritger-Peppas equation,ln Q = 0. 508 8 lnt-2. 285 0,r = 0. 961 5( p H 7. 4) and ln Q= 0. 449 9 lnt-1. 855 3,r = 0. 970 3( p H 6. 5),respectively. The experiment results proved that the nanoparticles prepared by emulsion/solvent evaporation method had uniform particle size,high encapsulation efficiency and in vitro sustained release characteristic,which might be a potential carrier for NT intracerebral drug delivery.

In order to optimize the prescription and preparation process of norcantharidin/tetrandrine dual loaded liposomes, the dual drug loaded liposomes were prepared by film dispersion-ultrasonic method using norcantharidin-mesoporous silica nanoparticles（MSN-NCTD）and tetrandrine（Tet）. With particle size and encapsulation efficiency as comprehensive indexes, the influences of phospholipid cholesterol amount, ultrasonic time and ultrasonic power on prescription process were investigated by orthogonal test; the

Arsenic trioxide (ATO) is an effective component of traditional Chinese medicine arsenic. The existing studies have shown its good inhibition and apoptosis ability on a variety of tumours. However, its toxicity and difficulties in the permeability into the blood brain barrier (BBB) has the limitation in the application of glioma treatment. Polyamide-amine dendrimer (PAMAM) is a synthetic polymer with many advantages, such as a good permeability, stability and biocompatibility. Additionally, the 5th generation of PAMAM is an ideal drug carrier due to its three-dimensional structure. In this study, the 5th generation of PAMAM co-modified with RGDyC and PEG, then confirmed by ¹H-NMR. The average particle size of nanoparticles was about 20 nm according to the nanoparticle size-potential analyser and transmission electron microscopy.

A novel targeting drug carrier (FA-BO-PAMAM) based on the PAMAM G5 dendrimer modified with borneol (BO) and folic acid (FA) molecules on the periphery and doxorubicin (DOX) loaded in the interior was designed and prepared to achieve the purposes of enhancing the blood-brain barrier (BBB) transportation and improving the drug accumulation in the glioma cells. 1H NMR was used to confirm the synthesis of FA-BO-PAMAM; its morphology and mean size were analyzed by dynamic light scattering (DLS) and transmission electron microscope (TEM). Based on the HBMEC and C6 cells, cytotoxicity assay, transport across the BBB, cellular uptake and anti-tumor activity in vitro were investigated to evaluate the properties of nanocarriers in vitro. The results showed that the nanocarrier of FA-BO-PAMAM was successfully synthesized, which was spherical in morphology with the average size of (22.28 ± 0.42) nm, and zeta potential of (7.6 ± 0.89) mV. Cytotoxicity and transport across the BBB assay showed that BO-modified conjugates decreased the cytotoxicity of PAMAM against both HBMEC and C6 cells and exhibited higher BBB transportation ability than BO-unmodified conjugates; moreover, modification with FA increased the total uptake of DOX by C6 cells and enhanced the cytotoxicity of DOX-polymer against C6 cells. Therefore, FA-BO-PAMAM is a promising nanodrug delivery system in employing PAMAM as a drug carrier and treatment for brain glioma.

Curcumin has a wide spectrum of pharmaceutical properties such as antitumor, antioxidant, antiamyloid, and anti-inflammatory activity. However, poor aqueous solubility and low bioavailability of curcumin are major challenge in its development as a useful drug. To overcome many of these problems, curcumin-loaded long-circulating liposomes (Cur-LCL) were prepared by the ethanol injection method. Morphology of Cur-LCL was observed by transmission electron microscope, mean particle size and Zeta potential were detected by laser particle size analyzer, entrapment efficiency and drug loading were evaluated by ultracentrifugation. The drug release behavior in vitro and pharmacokinetic behavior in rats of Cur-LCL were investigated with curcumin (Cur) and curcumin liposomes (Cur-Lips) as control. The results showed that the mean diameter of Cur-LCL was 110 nm, the Zeta potential was -5.8 mV. The entrapment efficiency and drug loading of Cur-LCL was 80.25%, 2.06%, respectively. The release behavior in vitro studied by dialysis in PBS buffer showed significant sustained release profile that 48.95% Cur were released from Cur-LCL in 7 h, 88.92% in 24 h. The pharmacokinetic parameters showed that compared with Cur and Cur-Lips, the t(1/2beta) of Cur-LCL was extended to 13 and 1.8-fold, respectively. Besides, the AUC values was significantly increased (P0.01), and the clearance was evidently decreased (P0.01). These results from in vitro and in vivo indicated that Cur-LCL were able to realize controlled drug release and increase circulation time.

OBJECTIVE To prepare chitosan-modified tripterygium glycoside nanoparticles (LMWC-TG-PLA-NPs), and assess its renal targeting property in rats. METHOD Chitosan-modified tripterygium glycoside nanoparticles (LMWC-TG-PLA-NPs) were prepared by modified spontaneous emulsification solvent evaporation method, and modified with 50% deacetylated low molecular weight chitosan (LMWC). The shape of nanoparticles was observed under a transmission electron microscope. The mean diameter of nanoparticles was measured by particle size analyzer. The drug encapsulation efficiency and drug loading were measured by centrifuge method. The in vitro release behavior was studied with dialysis bags. Renal microdialysis technique and renal artery administration technique were combined to study the renal targeting property of nanopartcles. LMWC-TG-PLA-NPs were administrated in rats by tail vein injection (TVI) and renal artery administration (RAA), respectively, with TG-PLA-NPs as the control group. Renal dialysis fluid was regularly collected to determine the drug concentration in the dialysis fluid, map drug concentration-time curves, and calculate AUC ratio in kidneys through the two injection approaches as the renal targeting parameter (RTP), in order to assess the renal targeting property of LMWC-TG-PLA-NPs. RESULTS The prepared LMWC-TG-PLA-NPs looked smooth and round. Their average diameter, polydispersity index, encapsulation efficiency and drug loading were (207.6 +/- 3.4) nm, (0.078 +/- 0.009)%, (61.83 +/- 2.43)%, and (10.70 +/- 0.37)%, respectively. The pH 7.4 PBS buffer solution containing 20% ethanol showed obvious sustained release behavior. LMWC-TG-PLA-NPs showed a RTP of 71.97%, which was 3.6 times of TG-PLA-NPs of the control group. CONCLUSION The prepared LMWC-TG-PLA-NPs showed high drug encapsulation efficiency and drug loading, with obvious sustained release characteristics and renal targeting property. LMWC-TG-PLA-NPs are expected to become a new type vector for reducing toxic and side effects of tripterygium glycoside. Meanwhile, a new method is established for assessing renal targeting property with AUC ratio in kidneys after administrated through caudal veins and renal arteries as the renal targeting parameter.

This study was aimed at the transport across blood-brain barrier (BBB) of polysorbate-80 modified neurotoxin loaded polybutylcyanoacrylate nanoparticle (P-80-NT-NP) and its cytotoxicity. An in vitro model of BBB using rat brain microvascular endothelial cells (rBMECs) was established. The cytotoxicity of P-80-NT-NP was measured by the MTT assays, where neurotoxin (NT), nanoparticle (NP), neurotoxin nanoparticle (NT-NP) as control, and the permeability of P-80-NT-NP was determined by using of Millicell insert coculture with rBMECs and fluorescence spectrophotometry. MTT results showed that NT, NP, NT-NP and P-80-NT-NP were avirulent to rBMECs when the concentration of NT was lower than 200 ng x mL(-1). But the cytotoxicity of NP, NT-NP and P-80-NT-NP would be augmented accordingly as concentration increased (P0.01), causing obvious reductions of cell survival rate, with no significant difference between them (P0.05). When the concentration of NT was 150 ng x mL(-1), the permeability on rBMECs of P-80-NT-NP and NT-NP were both significantly higher than that of NT (P0.01), and the permeability of P-80-NT-NP was greater than that of NT-NP (P0.05). In conclusion, polysorbate-80 modified neurotoxin nanoparticles can transport across the BBB, while concentration of NT is greater than 200 ng x mL(-1), P-80-NT-NP has a little cytotoxicity against rBMECs.