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In Vitro Characterization of Pluronic F127 and D--Tocopheryl Polyethylene Glycol 1000 Succinate Mixed Micelles as Nanocarriers for Targeted Anticancer-Drug Delivery
Adeel Masood Butt,Mohd Cairul Iqbal Mohd Amin,Haliza Katas,Narong Sarisuta,Wasu Witoonsaridsilp,Ruthairat Benjakul
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/916573
Abstract: Mixed micelles of Pluronic F127 and D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) in different molar ratios (10 : 0, 7 : 3, 5 : 5, and 3 : 7) were prepared to characterize this system as nanocarriers for targeted delivery of chemotherapeutic agents. Their size, zeta potential, critical micelle concentration, drug loading content, entrapment efficiency, drug release, cytotoxicity, and stability in serum were evaluated in vitro by using doxorubicin as the model anticancer drug. The micellar sizes ranged from 25 to 35 nm. The 7 : 3 and 5 : 5 micellar combinations had lower critical micelle concentrations ( M) than the 10 : 0 combination ( M). The entrapment efficiencies of the 7 : 3, 5 : 5, and 3 : 7 micellar combinations were 72%, 88%, and 69%, respectively. Doxorubicin release was greater at acidic tumour pH than at normal physiological pH. The doxorubicin-loaded mixed micelles showed greater percent inhibition and apoptosis activity in human breast adenocarcinoma (MCF-7) and acute monocytic leukaemia (THP-1) cell lines than free doxorubicin did. The mixed micelles were also stable against aggregation and precipitation in serum. These findings suggest that Pluronic F127-TPGS mixed micelles could be used as nanocarriers for targeted anticancer-drug delivery.
Uptake and transport of a novel anticancer drug-delivery system: lactosyl-norcantharidin-associated N-trimethyl chitosan nanoparticles across intestinal Caco-2 cell monolayers
Guan M, Zhu QL, Liu Y, Bei YY, Gu ZL, Zhang XN, Zhang Q
International Journal of Nanomedicine , 2012, DOI: http://dx.doi.org/10.2147/IJN.S30034
Abstract: ake and transport of a novel anticancer drug-delivery system: lactosyl-norcantharidin-associated N-trimethyl chitosan nanoparticles across intestinal Caco-2 cell monolayers Original Research (4421) Total Article Views Authors: Guan M, Zhu QL, Liu Y, Bei YY, Gu ZL, Zhang XN, Zhang Q Published Date April 2012 Volume 2012:7 Pages 1921 - 1930 DOI: http://dx.doi.org/10.2147/IJN.S30034 Received: 18 January 2012 Accepted: 11 February 2012 Published: 11 April 2012 Min Guan1, Qiao-Ling Zhu1, Yang Liu1, Yong-Yan Bei1, Zong-Lin Gu1, Xue-Nong Zhang1, Qiang Zhang2 1Department of Pharmaceutics, College of Pharmaceutical Science, Soochow University, Suzhou, People's Republic of China; 2Department of Pharmaceutics, School of Pharmaceutical Science, Peking University, Beijing, People's Republic of China Abstract: In this paper, novel liver-targeting nanoparticles (NPs), lactosyl-norcantharidin (Lac-NCTD)-associated N-trimethyl chitosan (TMC) NPs (Lac-NCTD-TMC-NPs), were prepared using ionic cross-linkage. The physical properties, particle size, and encapsulation efficiency of the nanoparticles were then investigated. The continuous line of heterogeneous human epithelial colorectal adenocarcinoma cells (Caco-2) cell monolayer model was used to study the transport mechanism of Lac-NCTD, and the effects of factors such as time, temperature, pH level, drug concentration, enhancers, and inhibitors. This model was also used to indicate the differences among Lac-NCTD, Lac-NCTD-associated chitosan NPs (Lac-NCTD-CS-NPs), and Lac-NCTD-TMC-NPs in the absorption and transportation of membranes. Drug concentration levels were measured using high-performance liquid chromatography. Active transport and paracellular transport were suggested to be both the primary and secondary mechanisms for Lac-NCTD absorption, respectively. Lac-NCTD uptake and absorption were not controlled by pH levels, but were positively correlated to uptake time, and negatively correlated to temperature. The basolateral to apical apparent permeability coefficients (Papps) were higher than those of the apical to basolateral values. The inhibitor of P-glycoprotein and the multidrug resistance-associated protein 2 significantly enhanced the uptake amount of Lac-NCTD. Compared with Lac-NCTD, Lac-NCTD-CS-NPs and Lac-NCTD-TMC-NPs significantly enhanced drug absorption. Additionally, the latter exhibited stronger action. Lac-NCTD-NPs could penetrate the plasma membrane of Caco-2 cells and translocate into the cytoplasm and even into the nucleus. Nanoparticles were uptaken into Caco-2 cells through the endocytosis pathway.
Preparation of Folate-Conjugated Pluronic F127/Chitosan Core-Shell Nanoparticles Encapsulating Doxorubicin for Breast Cancer Treatment
Chawan Manaspon,Kwanchanok Viravaidya-Pasuwat,Nuttaporn Pimpha
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/593878
Abstract: A targeting drug delivery system using folate-conjugated pluronic F127/chitosan core-shell nanoparticles was developed to deliver doxorubicin (DOX) to the target cancer cells. First, DOX was encapsulated in pluronic F127 micelle cores in the presence of sodium dodecyl sulfate (SDS) by a self-assembly method. To form a shell, a layer of either chitosan or folate-conjugated chitosan was deposited onto the pluronic micelles. The encapsulation efficiency was approximately 58.1±4.7%. The average size of the core-shell nanoparticles was 37.4±2.0 nm, while the zeta potential was 12.9±2.3 mV, indicating the presence of a shell layer and more stable particles. In an in vitro DOX release study, an initial burst release, followed by a sustained release, was observed within 24 hours. In addition, the core-shell nanoparticles showed greater cytotoxicity towards MCF-7 cells than free DOX, suggesting a better therapeutic efficacy in treating cancer.
CHITOSAN-GOLD NANOPARTICLES AS DELIVERY SYSTEMS FOR CURCUMIN
K. Satish Kumar* D. Gnanaprakash, K. Mayilvaganan, C. Arunraj and S. Mohankumar
International Journal of Pharmaceutical Sciences and Research , 2012,
Abstract: The present study deals with investigating the effect of chitosan nano particles as carriers for an anticancer drug curcumin. The chitosan-curcumin nanocapsules were prepared in the presence and absence of gold nanoparticles via solvent evaporation method. Scanning electron microscopy and transmission electron microscopy was done to characterize the drug entrapped nanocapsules. The average diameter of gold nanoparticles was found to be in the range of 18-20 nm and size of the nanocapsules was found to be in the range of 200-250 nm. Fourier transform-infrared analysis revealed no possible interactions among the constituents with the chitosan nanoparticles. The controlled drug release of anticancer drug entrapped nanocapsules was carried out in 0.1M HCl and 0.1M phosphate buffer (pH 7). Experimental studies revealed that curcumin encapsulated chitosan with gold nanoparticles was controlled and steady when compared with curcumin encapsulated chitosan nanoparticles. Application of in vitro drug release date to various kinetic equations indicated higuchi matrix model indicating uniform distribution of curcumin in the nanocapsules.
Pluronic and Chitosan based In situ gel system for periodontal application  [cached]
Gupta Himanshu,Sharma Aarti,Shrivastava Birendra
Asian Journal of Pharmaceutics , 2009,
Abstract: Aim of this paper is to develop and evaluate a physiologically activated in situ gel for local periodontal application. The gel, when at formulation pH and temperature (pH 6, 25°C) will be at liquid form which will be converted to gel at body pH and temperature (pH 7.4, 37°C) showing ease of administration and prolonged duration of action. Chitosan which was both mucoadhesive as well as pH simulative polymer was used in combination with pluronic F-127 which is a temperature simulated gelation polymer. Prilocaine hydrochloride was used as model drug to check the efficacy of the developed in-situ gel system. Different combination of Chitosan and pluronic F-127 were tested and final combination of 0.5% w/v and 10% w/v of Chitosan and pluronic F-127 respectively were selected and further evaluated for parameters like physicochemical properties, viscosity, gelation pH, gelation temperature, in-vitro release, sterility testing and stability testing. The system thus developed was found to be clear and have good viscosity with prolonged release at pH 7.4 and 37°C. The formulation can be easily packaged and sterilized with method employed. As per ICH guidelines gel was found to be stable and a shelf life of 2 years was assigned to the formulation.
Topical delivery of flurbiprofen from pluronic lecithin organogel  [cached]
Pandey M,Belgamwar V,Surana S
Indian Journal of Pharmaceutical Sciences , 2009,
Abstract: The purpose of this research is to formulate and evaluate the suitability of pluronic lecithin organogels containing flurbiprofen for topical application. Four formulations were developed using flurbiprofen, lecithin, Pluronic F127, isopropyl palmitate, water, sorbic acid and potassium sorbate were coded as FL1, FL2, FL3 and FL4. All the formulations carried 30% w/w of lecithin phase and 70% w/w of Pluronic phase. The formulated organogels were evaluated for appearance and feel psychorheologically, in vitro diffusion study, drug content, viscosity and pH. Release of flurbiprofen from all formulations was monitored via dialysis membrane-70 and Wistar rat skin as a semipermeable membrane into phosphate buffer saline (0.2 M, pH 7.4) using Keshary-Chien diffusion cell. The viscosities of different formulations were determined by using Brookfield Viscometer at 25°. An attempt has been made to explore the potential of pluronic lecithin organogels for topical delivery of flurbiprofen.
Genotoxicity and Cytotoxicity of the Anticancer Drugs Gemcitabine and Cisplatin, Separately and in Combination: in vivo Studies
Magdy S. Aly,Mohamad B. Ashour,Soheir M. El Nahas,Mona A. F. Abo Zeid
Journal of Biological Sciences , 2003,
Abstract: Both gemcitabine (2`,2`-difluorodeoxycytidine, dFdC) and cisplatin (cis-diammine-dichloroplatinum) have significant anticancer activity against ovarian, head and neck and non-small cell lung cancer (NSCLC). dFdC can be incorporated into DNA and RNA and inhibit DNA repair, while cisplatin can form Pt-DNA abducts. Because of differences in mechanisms of action and toxicity profiles, combination of the two drugs has enormous clinical potential. The combination of both is increasingly applied in clinical oncology. In this study, the genotoxic effects of cisplatin and gemcitabine separately and in combination were detected in the male mice bone marrow cells. Four doses were used for each drug. In CDDP experiments 6, 12, 24 and 36 mg kg ̄1 body weight were used. For dFdC 40, 50, 60 and 80 mg kg ̄1 body weight were used. Three drug combination doses were used: 4 mg kg ̄1 body wt. CDDP, 20 mg kg ̄1 body wt. dFdC; 6 mg kg ̄1 body wt. CDDP, 20 mg kg ̄1 body wt. dFdC; and 8 mg kg ̄1 body wt. CDDP, 20 mg kg ̄1 body wt. dfdC. In the drug combination experiments, CDDP were injected 4 hours prior to dfdC. Total chromosomal aberrations and sister chromatid exchanges (SCEs) frequencies were increased after exposure to combined drugs compared to exposure to each drug separately. Both single and combined drugs decreased the mitotic activity of the cells and induced a cell cycle delay with increasing the doses. In conclusion, the potentiation in chromosomal aberrations and sister chromatid exchanges formation might be a result of the inhibition of DNA repair by dFdC. The synergism between dFdC and CDDP appears to be mainly due to an increase in Pt-DNA adduct formation possibly related to changes in DNA due to dFdC incorporation into DNA.
Biodegradable Polymersomes for the Delivery of Gemcitabine to Panc-1 Cells  [PDF]
Nimil Sood,Walter T. Jenkins,Xiang-Yang Yang,Nikesh N. Shah,Joshua S. Katz,Cameron J. Koch,Paul R. Frail,Michael J. Therien,Daniel A. Hammer,Sydney M. Evans
Journal of Pharmaceutics , 2013, DOI: 10.1155/2013/932797
Abstract: Traditional anticancer chemotherapy often displays toxic side effects, poor bioavailability, and a low therapeutic index. Targeting and controlled release of a chemotherapeutic agent can increase drug bioavailability, mitigate undesirable side effects, and increase the therapeutic index. Here we report a polymersome-based system to deliver gemcitabine to Panc-1 cells in vitro. The polymersomes were self-assembled from a biocompatible and completely biodegradable polymer, poly(ethylene oxide)-poly(caprolactone), PEO-PCL. We showed that we can encapsulate gemcitabine within stable 200?nm vesicles with a 10% loading efficiency. These vesicles displayed a controlled release of gemcitabine with 60% release after 2 days at physiological pH. Upon treatment of Panc-1 cells in vitro, vesicles were internalized as verified with fluorescently labeled polymersomes. Clonogenic assays to determine cell survival were performed by treating Panc-1 cells with varying concentrations of unencapsulated gemcitabine (FreeGem) and polymersome-encapsulated gemcitabine (PolyGem) for 48 hours. 1?μM PolyGem was equivalent in tumor cell toxicity to 1?μM FreeGem, with a one log cell kill observed. These studies suggest that further investigation on polymersome-based drug formulations is warranted for chemotherapy of pancreatic cancer. 1. Introduction Pancreatic adenocarcinoma is the fourth highest cause of cancer death with a 5-year survival rate of less than 6% [1]. Despite the use of surgery, radiation, and/or chemotherapy [2], local recurrence and metastasis invariably occur. The causes of resistance of pancreatic tumors are not completely understood. The inability to deliver adequate adjuvant therapy due to local normal tissue toxicity, limitations caused by tumor microenvironment (hypoxia, pH), and active drug export out of tumor cells likely cause this resistance [3, 4]. Modifications to the delivery of chemotherapeutics that improve the therapeutic ratio (TR) are highly desirable in order to allow higher drug delivery while minimizing toxicity to normal tissues. Gemcitabine is a commonly used water soluble anticancer agent that acts as an antimetabolite; it is considered an efficacious addition to radiation therapy in pancreatic cancer [5]. Gemcitabine is an S-phase deoxycytidine analog (2′,2′-difluorodeoxycytidine). Its mechanism of action involves competitive incorporation into DNA, masked termination (causing termination of DNA synthesis without being excised out of the strand), and self-potentiation (promoting its own activity by inhibiting regulatory enzymes involved in
Synthesis and Biological Activity of Drug Delivery System Based on Chitosan Nanocapsules  [PDF]
Mohamed Gouda, Usama Elayaan, Magdy M. Youssef
Advances in Nanoparticles (ANP) , 2014, DOI: 10.4236/anp.2014.34019
Abstract: Chitosan nanocapsules containing naproxen as an active ingredient were synthesized by ionic gelation method in presence of polyanion tripolyphosphate as a crosslinker. The morphology and diameter of the prepared chitosan nanoparticles was characterized using scanning electron microscopy and transition electron microscopy. Different factors affecting on the size diameter of chitosan nanoparticles such as stirring time and temperature, pH values as well as chitosan concentration were studied. Different factors affecting on the immobilization of naproxen into chitosan nanoparticles such as time, temperature and pH values were optimized. Synthesized naproxen/chitosan nanocapsules were assessed against both Gram positive bacterial strain such as Bacillus subtilis and Staphylococcus aureus and Gram negative bacterial strain such as Pseudomonas aeruginosa and Escherichia coli. Also, the antifungal activity of the naproxen/chitosan nanocapsules against Saccharomyces cerevisiae was demonstrated. Super oxide dismutase like activity of naproxen/chitosan nanocapsules will be determined.
Enabling Anticancer Therapeutics by Nanoparticle Carriers: The Delivery of Paclitaxel  [PDF]
Yongjin Liu,Bin Zhang,Bing Yan
International Journal of Molecular Sciences , 2011, DOI: 10.3390/ijms12074395
Abstract: Anticancer drugs, such as paclitaxel (PTX), are indispensable for the treatment of a variety of malignancies. However, the application of most drugs is greatly limited by the low water solubility, poor permeability, or high efflux from cells. Nanoparticles have been widely investigated to enable drug delivery due to their low toxicity, sustained drug release, molecular targeting, and additional therapeutic and imaging functions. This review takes paclitaxel as an example and compares different nanoparticle-based delivery systems for their effectiveness in cancer chemotherapy.
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