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Octreotide (OCT) is a therapeutic peptide which is administered for the treatment of acromegaly. The purpose of this study was to design a new polyethylene glycol (PEG)–conjugated nanoparticle (PEG-NP) to overcome the short half-life and poor stability of OCT. The developed PEG-NPs were compared with non-PEGylated NPs with respect to their size, morphological characteristics, loading efficiency, release profile, and macrophage uptake. The OCT-loaded NPs and PEG-NPs were prepared by ionic complexion of chitosan (Cs) with either heparin (Hp) or PEGylated heparin (PEG-Hp). The chemical structure of PEG-Hp was confirmed by IR and proton nuclear magnetic resonance. Morphological analyses by scanning electron microscopy showed that NPs and PEG-NPs have a uniform shape. Dynamic laser scattering measurements indicated that hydrodynamic diameter of NPs and PEG-NPs were 222.5 ± 10.0 nm and 334.9 ± 6.7 nm, respectively. NPs and PEG-NPs had a positive zeta potential of about 32.5 ± 1.1 mv and 20.6 ± 2.4 mv, respectively. Entrapment efficiency was 61.4 ± 1.0% and 55.7 ± 2.4% for NPs and PEG-NPs, respectively. Compared with the NPs, the PEG-NPs exhibited a slower release profile. Subsequently, fluorescein isothiocyanate–labeled chitosanCs was synthesized and used to evaluate the stealth characteristic of PEG-NPs. In vitro macrophage uptake of fluorescently labeled NPs was measured by flow cytometry.

usc The aim of this study was to evaluate the in vitro and in vivo efficacy of paclitaxel-lapatinib-loaded Pluronic micelles. Lapatinib and pluronic sensitize the cancerous cells to paclitaxel via efflux pump inhibition. In addition, pluronic polymers can trigger intrinsic apoptosis pathways. Furthermore, micellar system can passively target the chemotherapeutic agents by enhanced permeability and retention effect. The paclitaxel-lapatinib-loaded micelles were characterized in means of encapsulation efficacy and size. The in vitro analyses were performed by MTT assay and uptake studies. Real-time imaging and in vivo anti-tumor efficacy studies were also performed. The prepared micelles have acceptable encapsulation ratio and size. Hemolysis assay confirmed that the micelles are hemo-compatible. MTT assay demonstrated that drug-loaded micelles have superior cytotoxicity compared with the naked drugs. The confocal microscopy and flowcytometry analyses showed that micelles are mainly internalized by endocytosis. According to the results of the in vivo imaging, the micelles are accumulated within liver. In vivo anti-tumor efficacy studies confirmed that tumor inhibition of drug-loaded micelles was significant compared to Intaxel (R). Refereed/Peer-reviewed

Background Multiple applications of antipsychotic agents are the main obstacle in the treatment of schizophrenia. Due to behavioral abnormalities, low compliance is observed in most of the psychotic patients. Designing of new drug delivery systems to overcome compliance problem seems to be necessary. In situ forming implants are a suitable choice for the delivery of antipsychotic agents due to their easy administration process and sustained release kinetics. Objective In this study, a novel poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) based nanoporous in situ implant system is developed for delivery of aripiprazole. Methods Entrapment efficiency, drug loading, rheological features, morphological characteristics and release profile of nano-porous in situ implant system are analyzed in this study. Results Entrapment efficiency and drug loading coefficient were modeled and impact of different experimental parameters was analyzed using D-optimal study. Entrapment efficiency and drug loading were optimized at 99.32% and 75.23%, respectively. Rheological analyses demonstrated that the developed formulation is a highly cross-linked gel with possible capability for controlled delivery of aripiprazole. According to the FTIR studies, aripiprazole was intact within polymer networks. SEM and light microscopic analyses proved the acceptable morphological characteristics of in situ gels. Release studies demonstrated a biphasic pattern of release. After initial burst release, a sustained pattern was observed for 18 days. The release data was fitted to Korsmeyer-Peppas model and release pattern was found out to be Fickian. In addition, the release profile was compared with novel pluroniccarrageenan based hydrogel system. Conclusion PHBV based in situ forming implant seems to be a novel formulation for delivery of Aripiprazole.

Refereed/Peer-reviewed Breast cancer is the leading cause of cancer death in women. Chemotherapy is regarded as the most essential strategy in inhibiting the proliferation of tumor cells. Paclitaxel is a widely used taxane; however, the side effects of available Cremophor-based formulations and also the limitations of passive targeting uncovered an essential need to develop tumor-specific targeted nanocarriers.A hyaluronic acid targeted liposomal formulation of paclitaxel was prepared in which, hyaluronic acid was electrostatistically attracted to the surface of liposomes. Liposomes, had a particle size of 106.4 +/- 3.2 nm, a weakly negative zeta potential of -9.7 +/- 0.8 mV and an acceptable encapsulation efficiency of 92.1 +/- 1.7%. The release profile of liposomes in buffer showed that 95% of PTX was released during 40 h. Confocal laser scanning microscopy and flow cytometry analysis showed the greater cellular internalization of coumarin-loaded liposomes compared to free coumarin. MTT assay on 4T1 and T47D cells demonstrated the stronger cytotoxic activity of liposomes in comparison to free paclitaxel. Cell cycle analysis showed that cells were mainly blocked at G2/M phases after 48 h treatment with liposomes. In vivo real time imaging on 4T1 tumor-bearing mice revealed that the liposomal formulation mainly accumulated in the tumor area. Liposomes also had better antitumor efficacy against Cremophor-based formulation. In conclusion, hyaluronic acid targeted paclitaxel liposome can serve as a promising targeted formulation of paclitaxel for future cancer chemotherapy.

usc A multifunctional nanocarrier with multilayer core-shell architecture was prepared by chemical modification of Fe3O4 magnetic nanoparticle (MNPs) with acrolein-styrene-polyethyleneimine (AL-St-PEI) via covalent bonding. MNPs were prepared by co-precipitation method, and then, thiol functionalized (MNPs-SH) were synthesized by treating MNPs with the (3-mercaptopropyl) trimethoxysilane. Subsequently, the copolymerization of St and AL was performed in the presence of the MNPs-SH and butyrolactam by thiol-lactam initiated radical polymerization. Finally, PEI was covalently bounded to the aldehyde groups on the surface of AL-St copolymer. The AL-St-PEI MNPs were investigated by FTIR, XRD, TGA, SEM and TEM. The drug release from AL-St-PEI MNPs was evaluated using doxorubicin as the model anticancer. Furthermore, to determine the effect of drug structure in the release profile from the modified MNPs, some lipophilic model drugs were studied in loading and release study. It was found that the nature of the drugs affect the release profile. The in vitro release modeling demonstrated that doxorubicin release is described by zero-order mechanism while release of lipophilic model drugs is controlled by fickian diffusion. Refereed/Peer-reviewed

A robust and rapid analysis method was developed and validated for the simultaneous assay of paclitaxel (PTX) and lapatinib (LPT) in a polymeric micelle formulation as a novel drug delivery system using high-performance liquid chromatography (HPLC). The assay was performed using the C18 MZ-Analytical Column (5 μm, 150 × 4.6 mm, OSD-3) which was protected with the C18 pre-column (5 μm, 4.0 × 4.6 mm, OSD-3). The mobile phase was composed of acetonitrile and water (70/30, V/V) with a flow rate of 0.5 mL/min and detection wavelength of 227 nm. Accuracy was reported as the relative error and was found to be less than 6.8%. The interday assay was evaluated to be 3.22% and 5.76% RSD for PTX and LPT, respectively. The intraday precision was found to be at its maximum value of 5.83% RSD. The limit of detection for both PTX and LPT was found to be 1 µg/mL by means of the newly developed method. The limit of quantitation for PTX and LPT was found to be 5 µg/mL. The calibration curves for both drugs were linear in the concentration range of 5 to 80 μg/mL. In vitro release for both drugs from the polymeric micelle was evaluated using the newly developed analysis method.