[Preparation and Characterization of Netupitant-loaded mPEG-PDLLA Nanoparticles].

OBJECTIVE: Methoxy poly (ethylene glycol)-poly (lactic acid) (mPEG-PDLLA) was used to increase water solubility of netupitant, thus to provide the experimental basis for development of the injection of netupitant. METHODS: Film hydration method was ultilized to prepare the netupitant-loaded mPEG-PDLLA nanoparticles (NT/mPEG-PDLLA-NPs). The preparation formulation and technology were optimized based on the single factor tests by investigating the effect of netupitant/mPEG-PDLLA mass ratio (m/m), filming temperature and time on the mean particle diameters and loading capacities. The size distributions and Zeta potentials of NT/mPEG-PDLLA-NPs were investigated using dynamic light scattering analysis, and the morphology was observed under the transmission electron microscope (TEM). The cytotoxicity of NT/mPEG-PDLLA-NPs evaluated by MTT method. RESULTS: The optimal NT/mPEG-PDLLA-NPs were achieved at the netupitant/mPEG-PDLLA mass ratio of 1/6 with filming temperature at 55 ℃ and filming time for 30 min. The resulting NT/mPEG-PDLLA-NPs displayed an opalescent and translucent appearance, with a high loading capacity of 14% and netupitant concentration of 10 mg/mL. NT/mPEG-PDLLA-NPs showed a spherical morphology, with a mean diameter of 58 nm and a nearly neutral Zeta potential of -0.29 mV. The NT/mPEG-PDLLA-NPs showed a cytotoxicity similar to free NT. CONCLUSION: Netupitant was successfully loaded into mPEG-PDLLA-NPs to significantly increased the water solubility, thus providing the experimental foundation for the further development of injection of netupitant.

Nanomedicine in the application of uveal melanoma.

Rapid advances in nanomedicine have significantly changed many aspects of nanoparticle application to the eye including areas of diagnosis, imaging and more importantly drug delivery. The nanoparticle-based drug delivery systems has provided a solution to various drug solubility-related problems in ophthalmology treatment. Nanostructured compounds could be used to achieve local ocular delivery with minimal unwanted systematic side effects produced by taking advantage of the phagocyte system. In addition, the in vivo control release by nanomaterials encapsulated drugs provides prolong exposure of the compound in the body. Furthermore, certain nanoparticles can overcome important body barriers including the blood-retinal barrier as well as the corneal-retinal barrier of the eye for effective delivery of the drug. In summary, the nanotechnology based drug delivery system may serve as an important tool for uveal melanoma treatment.

Nanoparticle-delivered quercetin for cancer therapy.

Quercetin, a natural protective bioflavonoid, possesses diverse pharmacologic effects, such as antioxidant, anti-inflammatory, anti-proliferative, and anti-angiogenic activities. Recently, quercetin's effect in cancer prevention and treatment was recognized. However, the poor water solubility and low-bioavailability of quercetin limit its clinical use in cancer therapy. Nanotechnology provides a method to create novel formulations for hydrophobic drug. Nanoparticles-delivered quercetin has attracted many attentions for its enhanced anticancer potential and promising clinical application. This review will discuss the application of nanotechnology in quercetin delivery for cancer therapy.

Preparation and characterization of monomethoxy poly(ethylene glycol)-poly(ε-caprolactone) micelles for the solubilization and in vivo delivery of luteolin.

Luteolin (Lu) is one of the flavonoids with anticancer activity, but its poor water solubility limits its use clinically. In this work, we used monomethoxy poly(ethylene glycol)-poly(e-caprolactone) (MPEG-PCL) micelles to encapsulate Lu by a self-assembly method, creating a water-soluble Lu/MPEG-PCL micelle. These micelles had a mean particle size of 38.6 ± 0.6 nm (polydispersity index = 0.16 ± 0.02), encapsulation efficiency of 98.32% ± 1.12%, and drug loading of 3.93% ± 0.25%. Lu/MPEG-PCL micelles could slowly release Lu in vitro. Encapsulation of Lu in MPEG-PCL micelles improved the half-life (t½ ; 152.25 ± 49.92 versus [vs] 7.16 ± 1.23 minutes, P = 0.007), area under the curve (0-t) (2914.05 ± 445.17 vs 502.65 ± 140.12 mg/L/minute, P = 0.001), area under the curve (0-∞) (2989.03 ± 433.22 vs 503.81 ± 141.41 mg/L/minute, P = 0.001), and peak concentration (92.70 ± 11.61 vs 38.98 ± 7.73 mg/L, P = 0.003) of Lu when the drug was intravenously administered at a dose of 30 mg/kg in rats. Also, Lu/MPEG-PCL micelles maintained the cytotoxicity of Lu on 4T1 breast cancer cells (IC50 = 6.4 ± 2.30 µg/mL) and C-26 colon carcinoma cells (IC50 = 12.62 ± 2.17 µg/mL) in vitro. These data suggested that encapsulation of Lu into MPEG-PCL micelles created an aqueous formulation of Lu with potential anticancer effect.

Treating acute cystitis with biodegradable micelle-encapsulated quercetin.

Intravesical application of an anti-inflammatory drug is an efficient strategy for acute cystitis therapy. Quercetin (QU) is a potent anti-inflammatory agent; however, its poor water solubility restricts its clinical application. In an attempt to improve water solubility of QU, biodegradable monomethoxy poly(ethylene glycol)-poly(ɛ-caprolactone) (MPEG-PCL) micelles were used to encapsulate QU by self-assembly methods, creating QU/MPEG-PCL micelles. These QU/MPEG-PCL micelles with DL of 7% had a mean particle size of <34 nm, and could release QU for an extended period in vitro. The in vivo study indicated that intravesical application of MPEG-PCL micelles did not induce any toxicity to the bladder, and could efficiently deliver cargo to the bladder. Moreover, the therapeutic efficiency of intravesical administration of QU/MPEG-PCL micelles on acute cystitis was evaluated in vivo. Results indicated that QU/MPEG-PCL micelle treatment efficiently reduced the edema and inflammatory cell infiltration of the bladder in an Escherichia coli-induced acute cystitis model. These data suggested that MPEG-PCL micelle was a candidate intravesical drug carrier, and QU/MPEG-PCL micelles may have potential application in acute cystitis therapy.

Efficient inhibition of ovarian cancer by truncation mutant of FILIP1L gene delivered by novel biodegradable cationic heparin-polyethyleneimine nanogels.

Filamin A interacting protein 1-like (FILIP1L), which was reported to be consistently absent in ovarian cancer cell lines, has been identified to hold therapeutic potential for inhibiting tumor growth, and its COOH-terminal truncation mutant (FILIP1LΔC103) was found to be more potent than the wild-type. The use of polymeric nanoparticles to deliver functional gene intraperitoneally holds much promise as an effective therapy for ovarian cancer. In this study, a recombinant plasmid expressing FILIP1LΔC103 (FILIP1LΔC103-p) was constructed, and biodegradable cationic heparin-polyethyleneimine (HPEI) nanogels were prepared to deliver FILIP1LΔC103-p into human ovarian cancer SKOV3 cells. The expression of FILIP1LΔC103 in vitro and in vivo was determined using RT-PCR and western blot analysis. Moreover, a SKOV3 intraperitoneal ovarian carcinomatosis model was established to investigate the antitumor activity of HPEI+FILIP1LΔC103-p complexes in nude mice. Tumor weights were evaluated during the treatment course. Cell proliferation and apoptosis were evaluated by Ki-67 immunochemical staining and TUNEL assay, respectively, and the antiangiogenic effect of FILIP1LΔC103-p was assessed by CD31 immunochemical staining and alginate-encapsulated tumor cell assay. FILIP1LΔC103-p could be efficiently transfected into SKOV3 cells by HPEI nanogels. Intraperitoneal administration of HPEI+FILIP1LΔC103-p complexes led to effective growth inhibition of ovarian cancer, in which tumor weight decreased by almost 72% in the treatment group compared with that in the empty-vector control group. Meanwhile, decreased cell proliferation, increased tumor cell apoptosis, and reduction in angiogenesis were observed in the HPEI+FILIP1LΔC103-p group compared with those in the control groups. These results indicated that HPEI nanogels delivering FILIP1LΔC103-p might be of value in the treatment against human ovarian cancer.

A novel drug and gene co-delivery system based on Poly(epsilon-caprolactone)-Poly(ethylene glycol)-Poly(epsilon-caprolactone) grafted polyethyleneimine micelle.

In this paper, we prepared a novel cationic self-assembled micelle from poly(epsilon-caprolactone)-poly(ethyl glycol)-poly(epsilon-caprolactone) grafted polyethyleneimine (PCEC-g-PEI). The PCEC-g-PEI micelles, formed by self-assembly method, had mean particle size of ca. 82 nm and zeta potential of +22.5 mV at 37 degrees C, and could efficiently transfer pGFP into HEK293 cells in vitro. Meanwhile, as a model hydrophobic chemotherapeutic drug, honokiol was loaded into PCEC-g-PEI micelles by direct dissolution method assisted by ultrasonication. The honokiol loaded cationic PCEC-g-PEI micelles could effectively adsorb DNA onto its surface, while it could release honokiol in an extended period in vitro. This study demonstrated a novel DNA and hydrophobic chemotherapeutic drug co-delivery system.

Preparation and characterization of honokiol nanoparticles.

In this paper, honokiol nanoparticles were prepared by emulsion solvent evaporation method. The prepared honokiol nanoparticles were characterized by particle size distribution, morphology, zeta potential and crystallography. Results showed that the obtained honokiol nanoparticles at size of 33 nm might be amorphous, and could be well dispersed in water. Due to the great dispersibility in water, the obtained honokiol nanoparticles might have great potential in medical field.

Preparation and characterization of magnetic poly(epsilon-caprolactone)-poly(ethylene glycol)-poly(epsilon-caprolactone) microspheres.

In this article, nano-magnetite particles (ferrofluid, Fe3O4) were prepared by chemical co-deposition method. A series of biodegradable triblock poly(epsilon-caprolactone)-poly(ethylene glycol)-poly(epsilon-caprolactone) (PCL-PEG-PCL, PCEC) copolymers were synthesized by ring-opening polymerization method from epsilon-caprolactone (epsilon-CL) initiated by poly(ethylene glycol) diol (PEG) using stannous octoate as catalyst. And the magnetic PCEC composite microspheres were prepared by solvent diffusion method. The properties of the ferrofluid, PCEC copolymer, and magnetic PCEC microspheres were studied in detail by SEM, VSM, XRD, Malvern Laser Particle Sizer, 1H-NMR, GPC, and TG/DTG. Effects of macromolecular weight and concentration of polymer, and the time for ultrasound dispersion on properties of magnetic microspheres were also investigated. The obtained magnetic PCEC microspheres might have great potential application in targeted drug delivery system or cell separation.

Synthesis, characterization, and hydrolytic degradation behavior of a novel biodegradable pH-sensitive hydrogel based on polycaprolactone, methacrylic acid, and poly(ethylene glycol).

In this work, a new kind of biodegradable pH-sensitive hydrogel was successfully synthesized by UV-initiated free radical polymerization. The obtained hydrogel was characterized by (1)H NMR and FTIR. Swelling behavior in different aqueous media and pH responsivity of the hydrogels were studied in detail as well. With increase in pH from 1.2 to 7.2, swelling ratio of the hydrogel increased. The morphology was observed by scanning electron microscopy, and the hydrolytic degradation behavior was also investigated in this work.

Thermoreversible gel-sol behavior of biodegradable PCL-PEG-PCL triblock copolymer in aqueous solutions.

A series of biodegradable PCL-PEG-PCL block copolymers were successfully synthesized by ring-opening polymerization of epsilon-caprolactone initiated by poly(ethylene glycol) (PEG), which were characterized by (1)H NMR, (13)C NMR, and FTIR. Their aqueous solution displayed special gel-sol transition behavior with temperature increasing from 4 to 100 degrees C, when the polymer concentration was above corresponding critical gel concentration (CGC). The gel-sol phase diagram was recorded using test tube inverting method and DSC method, which depended not only on chemical composition of copolymers, but also on heating history of copolymer's aqueous solution. As a result, the gel-sol transition temperature could be adjusted, which might be very useful for its application in biomedical fields such as injectable drug delivery system. And the typical shell-core structure of PCL-PEG-PCL micelles was introduced. The micelle-packing and partial crystallization might be the key gelation machanism for this gel-sol transition behavior of PCL-PEG-PCL aqueous solution.

One-step preparation of poly(epsilon-caprolactone)-poly(ethylene glycol)-poly(epsilon-caprolactone) nanoparticles for plasmid DNA delivery.

In this article, a kind of biodegradable poly(epsilon-caprolactone)-Poly(ethylene glycol)-poly(epsilon-caprolactone) (PCL-PEG-PCL, PCEC) copolymer was synthesized by ring-opening polymerization method. The PCEC nanoparticles were prepared at one-step by modified emulsion solvent evaporation method using CTAB as stabilizer. With increase in PCEC concentration, the particle size increased obviously, but zeta potential only increased slightly. The obtained cationic PCEC nanoparticle was employed to condense and adsorb DNA onto its surface. Plasmid GFP (pGFP) was used as model plasmid to evaluate the loading capacity of cationic PCEC nanoparticles in this work. The DNA/nanoparticles weight ratio at 1:16 induced almost neutral zeta potential of DNA-nanoparticles complex. At this time, the size of complex became abnormally large which implied aggregates formed. So DNA-nanoparticles weight ratio should be chosen carefully. The cationic PCEC nanoparticles had the capacity of condensing plasmid DNA into complex when the DNA/nanoparticles weight ratio was lower than 1:8, which was evidenced by gel retardation assay. In vitro release behavior of DNA/nanoparticle complexes was also studied here. The obtained cationic PCEC nanoparticles might have great potential application in DNA delivery.

Preparation, characterization, and optimization of pancreas-targeted 5-Fu loaded magnetic bovine serum albumin microspheres.

The magnetic bovine serum albumin (BSA) microspheres (MS) were prepared by emulsification/solidification method. In this experiment, two kinds of magnetic MS, e.g. BSA MS and PEG-incorporated BSA microspheres (PMS) were prepared. The obtained MS were characterized by Malvern laser particle sizer and scanning electron microscopy (SEM). The obtained MS were spherical and about 1.3 microm in size. The magnetic responsivity and in vitro release behavior of these MS were studied in detail. The in vivo distribution and targeting delivery of 5-fluorouracil (5-Fu) magnetic MS after artery administration were studied in rat. The results showed that PMS could efficiently delivery 5-Fu to the targeted site compared with BSA MS without PEG MS and free drug.