Growth of metal-semiconductor core-multishell nanorods with optimized field confinement and nonlinear enhancement.

This paper describes a facile method for the synthesis of Au/AuAg/Ag2S/PbS core-multishell nanorods with double trapping layers. The synthesis, in sequence, involved deposition of Ag shells onto the surfaces of Au nanorod seeds, formation of AuAg shells by a galvanic replacement reaction, and overgrowth of the Ag2S shells and PbS shells. The resulting core-multishell nanorod possesses an air gap between the Au core and the AuAg shell. Together with the Ag2S shell, the air gap can efficiently trap light, causing strong field confinement and nonlinear enhancement. The as-prepared Au/AuAg/Ag2S/PbS core-multishell nanorods display distinct localized surface plasmon resonance and nonlinear optical properties, demonstrating an effective pathway for maneuvering the optical properties of nanocavities.

[Preparation of stearic acid solid lipid nanoparticles containing podophyllotoxin].

OBJECTIVE: To improve the therapeutic efficacy and reduce the adverse effect of podophyllotoxin (PPT) by wrapping it in stearic acid solid lipid nanoparticles. METHODS: Stearic acid solid lipid nanoparticles containing podophyllotoxin was prepared using modified microemulsion technique, whose morphology was examined by transmission electron microscope. High-performance of liquid chromatography was employed to determine the entrapment efficiency of PPT in the nanoparticles. RESULT: The entrapment efficiency of PPT in the nanoparticles was 85.6% and the mean diameter of the particles was 56.5+/-25.8 nm. CONCLUSION: The stearic acid solid lipid nanoparticles has high entrapment efficiency for PPT and is homogeneous in size, which can be a promising targeted preparation for epidermal delivery.

[Preparation and characterization of podophyllotoxin-dipalmitoylphosphatidylcholine proliposome].

OBJECTIVE: To prepare podophyllotoxin-dipalmitoylphosphatidylcholine (PPT-DPPC) proliposomes (PPT-DPPC-PL) for improvement of the stability of PPT-DPPC liposome. METHODS: Freeze-drying method was used to prepare PPT-DPPC-PL, and the particle morphology, size range, encapsulation efficiency and stability of PPT-DPPC liposome were investigated. RESULTS: After hydration of PPT-DPPC-PL, PPT-DPPC liposome appeared multivesicular under electron microscope and the particles were distributed homogeneously with an average particle size of 1.45+/-0.38 microm. The encapsulation efficiency of PPT was 72.3%, and after storage at 4 to 40 degrees Celsius; for 1 to 6 months, the proliposome remained stable. CONCLUSION: The prepared PPT-DPPC-PL particles by freeze-drying method are evenly distributed. The preparation method is relatively simple with higher embedding ratio and better stability.

[Treatment of recurrent condyloma acuminatum with solid lipid nanoparticle gel containing podophyllotoxin: a randomized double-blinded, controlled clinical trial].

OBJECTIVE: To observe the clinical efficacy and safety of podophyllotoxin delivered via solid lipid nanoparticle gel for topic treatment of recurrent condyloma acuminatum. METHODS: In a randomized double-blinded study, podophyllotoxin solid lipid nanoparticles gel and routine podophyllotoxin gel preparation was applied respectively for treatment of 97 volunteer patients with recurrent condyloma acuminatum. The therapeutic effect, condyloma acuminatum relapse following the treatment and adverse effect were evaluated. RESULTS: The wart clearance rate in the condyloma acuminatum patients in the first treatment course with podophyllotoxin solid lipid nanoparticle gel reached 97.1%, close to that with the routine preparation of 90.6%, but the nanoparticle preparation significantly reduced the recurrence rate and adverse effect (P<0.01). CONCLUSION: Podophyllotoxin delivered via solid lipid nanoparticle gel can effectively clear condyloma acuminatum and reduce its recurrence rate with only mild, tolerable adverse effect.