Study on formulation variables of methotrexate loaded mesoporous MCM-41 nanoparticles for dissolution enhancement

Preparation, Characterization, and Evaluation of Mesoporous Silica Nanoparticles in Enhancing Oral Bioavailability of Poorly Water-Soluble Drugs

BACKGROUND

Breviscapine (BVP) is one of the extracts of several flavonoids of Erigeron breviscapus, which has been widely used in the treatment of cerebral infarction and its sequelae, cerebral thrombus, coronary heart disease, and angina pectoris. But BVP has poor solubility.

OBJECTIVE

The objective of the study is to develop mesoporous silica nanoparticles (MSNs) that can be loaded with a drug with poor water solubility. The MSNs, which were designed for oral administration, enhanced both the dissolution rate and drug loading capacity.

METHODS

The use of MSNs as an oral drug delivery system was investigated by SEM, TEM, BETBJH, XRD, FT-IR, and HPLC. Additionally, we examined the oral bioavailability of BVP loaded onto MSNs and examined the cellular cytotoxicity of MSNs.

RESULTS

The results indicate that the oral bioavailability of BVP after loading onto MSNs was greater than that of a marketed product. Furthermore, we studied the mechanism by which MSNs enhance the oral absorption of BVP.

CONCLUSION

MSNs have the potential to enhance the oral bioavailability of poorly water-soluble drugs by accelerating the drug dissolution rate.

Application of chitosan modified nanocarriers in breast cancer

As per the WHO, every year around 2.1 million women are detected with breast cancer. It is one of the most invasive cancer in women and second most among all, contributing around 15% of death worldwide. The available anticancer therapies including chemo, radio, and hormone therapy are associated with a high load of reversible and irreversible adverse effects, limited therapeutic efficacy, and low chances of quality survival. To minimize the side effects, improving therapeutic potency and patient compliance promising targeted therapies are highly desirable. In this sequence, various nanocarriers and target modified systems have been explored by researchers throughout the world. Among these chitosan-based nanocarriers offers one of the most interesting, flexible, and biocompatible systems. The unique characteristics of chitosan like surface flexibility, biocompatibility, hydrophilicity, non-toxic and cost-effective behavior assist to overcome the inadequacy of existing therapy. The present review throws light on the successes, failures, and current status of chitosan modified novel techniques for tumor targeting of bioactives. It also emphasizes the molecular classification of breast cancer and current clinical development of novel therapies. The review compiles most relevant works of the past 10 years focusing on the application of chitosan-based nanocarrier against breast cancer.

Investigation of dimyristoyl phosphatidyl glycerol and cholesterol based nanocochleates as a potential oral delivery carrier for methotrexate

Methotrexate (MTX), a biopharmaceutical classification system-IV anticancer drug, exhibits low therapeutic efficacy. Moreover, its clinical applications were restricted due to its multidrug resistance (MDR) in cancer and its toxic effects. The present investigation was to fabricate 1, 2-dimyristoyl-sn-glycero-3-phospho-rac-(1-glycerol) sodium (DMPG-Na), (3β)-cholest-5-en-3-ol (cholesterol) and calcium-based nanocochleates (NCs) as a potential oral delivery carrier for MTX to enhance its therapeutic efficacy with low toxicity. MTX-loaded NCs (MTX-NCs) was developed by the addition of calcium ion into preformed nanoliposomes (MTX-NLs) comprising MTX, DMPG-Na, with cholesterol and evaluated by in-vitro and in-vivo methods in comparison with MTX-NLs and pure MTX. Stable tubular rod structure of MTX-NCs possessing particle size, encapsulation efficiency and zeta potential of 374.1 ± 2.2 nm, 78.63 ± 2.12% and -71.2 mV, respectively were obtained from homogenous unilamellar, discrete and spherical structured MTX-NLs with a diameter and zeta potential of 363.3 ± 3.7 nm and -74.6 mV respectively. A thermal study revealed an amorphous state of MTX in MTX-NCs. Pharmacokinetics study in rats, MTX-NLs and MTX-NCs were showed controlled release with 5 and 6 fold improvements in oral bioavailability. Moreover, MTX-NCs showed low tissue distribution. These results collectively suggest that the developed system could be used to improve the therapeutic efficacy of MTX.

Methotrexate-Loaded Gelatin and Polyvinyl Alcohol (Gel/PVA) Hydrogel as a pH-Sensitive Matrix

The aim was to formulate and evaluate Gel/PVA hydrogels as a pH-sensitive matrix to deliver methotrexate (MTX) to colon. The primed Gel/PVA hydrogels were subjected to evaluation for swelling behavior, diffusion coefficient, sol-gel characteristic and porosity using an acidic (pH 1.2) and phosphate buffer (PBS) (pH 6.8 & pH 7.4) media. Fourier transform infrared spectroscopy (FTIR) and thermal gravimetric analysis (TGA) were performed to evaluate the chemical compatibility of the Gel/PVA hydrogel. The shape alteration and release of Gel/PVA hydrogel was conducted at pH 1.2, pH 6.8 and pH 7.4. The drug release kinetic mechanism was determined using various kinetic equations. The physicochemical evaluation tests and drug release profile results were found to be significant (p < 0.01). However, it was dependent on the polymers' concentration, the pH of the release media and the amount of the cross-linking agent. Hydrogels containing the maximum amount of gel showed a dynamic equilibrium of 10.09 ± 0.18 and drug release of 93.75 ± 0.13% at pH 1.2. The kinetic models showed the release of MTX from the Gel/PVA hydrogel was non-Fickian. The results confirmed that the newly formed Gel/PVA hydrogels are potential drug delivery systems for a controlled delivery of MTX to the colon.

Mesoporous Silica Particles as Drug Delivery Systems-The State of the Art in Loading Methods and the Recent Progress in Analytical Techniques for Monitoring These Processes

Conventional administration of drugs is limited by poor water solubility, low permeability, and mediocre targeting. Safe and effective delivery of drugs and therapeutic agents remains a challenge, especially for complex therapies, such as cancer treatment, pain management, heart failure medication, among several others. Thus, delivery systems designed to improve the pharmacokinetics of loaded molecules, and allowing controlled release and target specific delivery, have received considerable attention in recent years. The last two decades have seen a growing interest among scientists and the pharmaceutical industry in mesoporous silica nanoparticles (MSNs) as drug delivery systems (DDS). This interest is due to the unique physicochemical properties, including high loading capacity, excellent biocompatibility, and easy functionalization. In this review, we discuss the current state of the art related to the preparation of drug-loaded MSNs and their analysis, focusing on the newest advancements, and highlighting the advantages and disadvantages of different methods. Finally, we provide a concise outlook for the remaining challenges in the field.

Nanoclay-based drug delivery systems and their therapeutic potentials

Safe, therapeutically effective, and patient-compliant drug delivery systems are needed to design novel tools and strategies to combat the deadliest of diseases such as cancer, SARS, H7N9 avian influenza, and dengue infection. The major challenges in drug delivery are cytotoxicity, poor biodistribution, insufficient functionality, ineffective drug incorporation in delivery devices, and subsequent drug release. Clay minerals are a class of nanolayered silicates that have good biocompatibility, high specific surface area, chemical inertness, colloid, and thixotropy, and are attractive practical and potential nanomaterials in medicine. These properties enable the usage of nanoclays as drug carriers for the delivery of antibiotics, antihypertensive drugs, anti-psychotic, and anticancer drugs. The review examines the latest advances in nanoclay-based drug delivery systems and related applications in gene therapy and tissue engineering. Clay minerals, particularly montmorillonite, kaolinite, and halloysite are used to delay and/or target drug release or even improve drug dissolution due to their surface charge. Chemical modification of clay minerals such as intercalation of ions into the interlayer space of clay minerals or surface modification of clay minerals is a strategy to tune the properties of nanoclays for the loading and release of a drug. The modified nanoclay can take up drugs by encapsulation, immobilization, ion exchange reaction, or electrostatic interactions. Controlled drug release from the drug-clay originates from the incorporation and interactions between the drug and inorganic layers, including electrostatic interactions and hydrogen bonding. Montmorillonite has proven non-toxic through hematological, biochemical, and histopathological analyses in rat. Montmorillonite can also act as a potent detoxifier. Halloysite nanotubes can bind synthetic and biological components such as chitosan, gelatin, and alginate innate nanocarriers for the improved loading and controlled release of drugs, proteins, and DNA. The peculiar properties of clay nanoparticles lead to promising applications in drug delivery, gene delivery, tissue engineering, cancer and stem cell isolation, and bioimaging.

Recent Advances in Oral Nano-Antibiotics for Bacterial Infection Therapy

Bacterial infections are the main infectious diseases and cause of death worldwide. Antibiotics are used to treat various infections ranging from minor to life-threatening ones. The dominant route to administer antibiotics is through oral delivery and subsequent gastrointestinal tract (GIT) absorption. However, the delivery efficiency is limited by many factors such as low drug solubility and/or permeability, gastrointestinal instability, and low antibacterial activity. Nanotechnology has emerged as a novel and efficient tool for targeting drug delivery, and a number of promising nanotherapeutic strategies have been widely explored to overcome these obstacles. In this review, we explore published studies to provide a comprehensive understanding of the recent progress in the area of orally deliverable nano-antibiotic formulations. The first part of this article discusses the functions and underlying mechanisms by which nanomedicines increase the oral absorption of antibiotics. The second part focuses on the classification of oral nano-antibiotics and summarizes the advantages, disadvantages and applications of nanoformulations including lipid, polymer, nanosuspension, carbon nanotubes and mesoporous silica nanoparticles in oral delivery of antibiotics. Lastly, the challenges and future perspective of oral nano-antibiotics for infection disease therapy are discussed. Overall, nanomedicines designed for oral drug delivery system have demonstrated the potential for the improvement and optimization of currently available antibiotic therapies.

Biodegradable nanocarriers based on chitosan-modified mesoporous silica nanoparticles for delivery of methotrexate for application in breast cancer treatment

Nanocarriers have demonstrated great promise in the delivery of hydrophobic drugs particularly to tumor spaces by enhanced permeability and retention (EPR) effects. Mesoporous silica nanoparticles (MSNs) are the attractive nanocarrier system to reduce the drug's toxic side effects, enable controlled drug release, prevent drug degradation and provide a biocompatible and biodegradable high surface area carrier. Surface-modified MSNs have been applied to increase drug loading and efficiency. In this study, functionalized MSNs loaded with methotrexate (MTX) were designed for use as a cytotoxic agent. The MSNs were first modified with 3-triethoxysilylpropylamine (APTES) and then with chitosan through covalent coupling mediated by glutaraldehyde. The physicochemical properties of the nanoparticles were optimized for each step. The loading percentage (12.2%) and release profile of MTX as an anti-breast cancer drug, loaded at amine-modified MSNs, were measured via high performance liquid chromatography (HPLC). Moreover, the uptake profiles of fluorescein isothiocyanate (FITC)-labeled MSN-APTES-chitosan with or without MTX were monitored on MCF7 cancer cells via confocal microscopy. Following exposure of nanoparticles to body fluids, they were surrounded by specific proteins that may affect their cellular uptake. Hence, the adsorption profiles of protein corona on the surface of MSN, amine-modified MSN and MTX-loaded MSN-APTES-chitosan were analyzed. The cytotoxic potential for killing breast cancer cells was also studied. The MTX loaded MSN-APTES-chitosan showed a positive effect at a low dose (0.5 μM MTX). In this study, we introduce a new method to synthesize biodegradable MSNs with small and uniform particle size, achieve high MTX loading via covalent amine and chitosan-functionalization, monitor the cellular uptake and demonstrate the potential to decrease the viability of breast cancer cells at low dose.

Mucoadhesive and pH responsive fucoidan-chitosan nanoparticles for the oral delivery of methotrexate

Considering the potential of mucoadhesive properties of nanoparticles in oral delivery, this work describes the preparation and characterization of fucoidan/chitosan nanoparticles loaded with methotrexate (MTX) intended to lung cancer therapy. The nanoparticles were produced and characterized in terms of size, surface charge, entrapment efficiency, and morphology. The size of the developed nanoparticles was around 300 nm, the zeta potential value was negative (ca. -30 mV), revealing a low tendency to aggregate. The self-assembled fucoidan/chitosan nanoparticles were stable at acidic pH (1.6-5.2), without disintegration under pH 6-7.4, revealing resistance through the gastrointestinal tract, and were found to be mucoadhesive suggesting ability to enhance drug oral bioavailability. Lung cancer cells quickly internalized the developed nanoparticles. Moreover, MTX-loaded fucoidan/chitosan nanoparticles up to 245 μg mL-1 in polymer equivalent to 23.5 μg mL-1 of MTX were safe towards fibroblasts but hampered lung cancer cell proliferation mediated by an apoptotic process. MTX-loaded nanoparticles were 7-fold more effective in inhibiting lung cancer cells proliferation than the free drug, showing the potential of fucoidan-chitosan nanoparticles to improve the cytotoxicity of free methotrexate on A549 lung cancer cells. These results also demonstrate that fucoidan/chitosan nanoparticles may provide a suitable platform for poor-water soluble compounds' oral delivery.

Formulation and optimization of drug-loaded mesoporous silica nanoparticle-based tablets to improve the dissolution rate of the poorly water-soluble drug silymarin

Porous carriers have been put forward as a promising alternative for stabilizing the amorphous state of loaded drugs, and thus significantly improving the dissolution rate of poorly soluble compounds. The purpose of this study was to enhance the saturation solubility, dissolution rate and drug loading of the poorly water-soluble drug silymarin via incorporation into mesoporous silica nanospheres within a lyophilized tablet to obtain a unique formulation. 3² full factorial design was applied to study the effect of both independent variables, polyvinyl alcohol (PVA) as stabilizer and binder and sucrose as cryoprotectant and disintegrant; and on the dependent variables that included the mean particle size (Y₁), disintegration time (Y₂), tablet strength (Y₃) and % of drug release after 2 min, R_2min,Y₄. The drug-loaded mesoporous silica nanospheres and the optimized formula was evaluated by different characterization methods: scanning electron microscopy, transmission electron microscopy, differential scanning calorimetry, X-ray diffractometry and Fourier transform infrared spectroscopy; as well as drug content, saturation solubility and moisture content. The evaluation demonstrated that the loaded mesoporous silica nanospheres and the optimized formula are in amorphous state without any chemical interaction with the silica matrix or the stabilizer. Moreover, the drug was stably maintained in nanosize range with narrow particle size distribution. Furthermore, the optimized lyophilized tablets had highly porous structure, low friability (less than 1%), fast disintegration (less than 30 s), high tablet strength, low moisture content (less than 1%), remarkably increased dissolution rate and noticeable improvement in saturation solubility.

Self-microemulsifying drug delivery system (SMEDDS) for improved oral delivery and photostability of methotrexate

Purpose: The objective of this study was to exploit a novel methotrexate (MTX)-loaded solid self-microemulsifying drug delivery system (SMEDDS) with enhanced bioavailability and photostability. Materials and methods: The optimized liquid SMEDDS was composed of castor oil, Tween^® 80, and Plurol^® diisostearique at a voluminous ratio of 27:63:10. The solid SMEDDS was formulated by spray drying liquid SMEDDS with the solid carrier (calcium silicate). Particle size analyzer, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and Fourier transform infrared (FTIR) spectroscopy experiments characterized the physiochemical properties of the MTX-loaded solid SMEDDS. These properties include a z-average diameter of emulsion around 127 nm and the amorphous form of the solid SMEDDS. Furthermore, their solubility, dissolution, and pharmacokinetics in Sprague-Dawley rats were analyzed in comparison with the MTX powder. Results: The final dissolution rate and required time for complete release of solid SMEDDS were 1.9-fold higher and 10 min shorter, respectively, than those of MTX powder. Pharmacokinetic analysis demonstrated 2.04- and 3.41-fold increments in AUC and Cmax, respectively in comparison to MTX powder. The AUC and C_max were significantly increased in solid SMEDDS. Finally, the photostability studies revealed the substantially enhanced photostability of the MTX-loaded SMEDDS under the forced degradation and confirmatory conditions. Conclusion: This solid SMEDDS formulation could be an outstanding candidate for improving the oral bioavailability and photostability of MTX.

Curcumin ameliorates the targeted delivery of methotrexate intercalated montmorillonite clay to cancer cells

Montmorillonite Clay (MMT) is aimed to develop as an orally administrable drug delivery vehicle with enhanced efficacy. Aiming to enhance the therapeutic index of methotrexate, curcumin is concomitantly used with methotrexate in the present study. Being folate antagonist in nature, methotrexate is internalized into cells by folate receptor (FR); which is over-expressed in certain human cancer cells such as cervical carcinoma cells (HeLa). Firstly, montmorillonite Clay (MMT) is organically modified (OMMT) with cetyl trimethyl ammonium bromide (CTAB) and used to intercalate curcumin and methotrexate separately, designated as OMMT-Cur and OMMT-MTX, respectively. XRD pattern demonstrated successful intercalation of therapeutics and an increase in clay interlayer distance facilitated by CTAB. The dissolution kinetics of methotrexate follows Higuchi model for both Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF), while the release kinetics for curcumin fitted into Higuchi model for SGF and Hixson-Crowell model for SIF, respectively. OMMT-MTX are able to discriminate FR-positive HeLa cells from FR-negative breast cancer cells (MCF7); irrespective of alike cellular phenotypes. Further, the pre-treatment of HeLa cells with curcumin improves its sensitivity towards methotrexate causing a greater killing of the Hela cells. Together, the results propose the concomitant use of curcumin and methotrexate for successfully targeting highly invasive FR-positive carcinomas by means of folate receptor using MMTs.

Effects of PEG surface density and chain length on the pharmacokinetics and biodistribution of methotrexate-loaded chitosan nanoparticles

Background

One of the most important aspects of drug delivery is extended nanoparticle (NP) residence time in vivo. Herein, we report a series of methotrexate (MTX)-loaded chito-san (CS) NPs coated with differently sized methoxy polyethylene glycol (mPEG) at different mPEG surface densities.

Materials and methods

MTX was incorporated into NPs (112.8–171.2 nm in diameter) prepared from the resulting mPEG-g-CS. The NPs had a zeta potential of +7.4–35.0 mV and MTX loading efficiency of 17.1%–18.4%. MTX/mPEG-g-CS NPs showed an initial burst release of MTX followed by a sustained-release profile in PBS at pH 7.4.

Results

The in vitro cellular uptake study showed that MTX accumulation in J774A.1 macrophage cells decreased with increasing the mPEG surface density or the mPEG molecular weight. The pharmacokinetic study on Sprague Dawley rats revealed an increase in AUC0–72 h (area under the plasma drug concentration–time curve over a period of 72 hours) with increasing the mPEG surface density or the mPEG molecular weight and a linear correlation between the mPEG surface density and AUC_{0–72 h}.

Conclusion

The biodistribution study on Institute of Cancer Research (ICR) mice revealed that MTX/mPEG-g-CS NPs significantly enhanced blood circulation time in the body and decreased accumulation in liver, spleen, and lung. These results suggest the potential of the mPEG-g-CS NPs as a promising candidate for drug delivery.

Facile Synthesis of Chitosan Capped Mesoporous Silica Nanoparticles: A pH Responsive Smart Delivery Platform for Raloxifene Hydrochloride

An encapsulation of model drug raloxifene hydrochloride (RAL) inside the chitosan decorated pH responsive mesoporous system has a greater potential for accumulating in the tumor cells. The present study involves synthesis of surface modified mesoporous silica nanoparticles (MSN) with the aim of achieving pH sensitive drug delivery system. A silanol skeleton of MSN has been productively modified to amine intermediate which served as a firm platform to adapt chitosan grafted assembly and systematically evaluated. RAL incorporation inside the featured mesopores was performed employing novel immersion solvent evaporation methodology and evaluated further. The pH responsive behavior of formulated nano framework was studied at three different pH of a phosphate buffer saline individually. The in vitro cell viability assay on MCF-7 breast carcinoma cells was performed in time and concentration dependent manner. Finally, the hemolysis assay of designed nanoparticle was accomplished to envisage the hemocompatibility. The outcome of characterization details unveiled a perfect 2D hexagonal spherical structure gifted with higher surface area and optimum pore size for designed nanoparticles. The higher percentage grafting of amine and chitosan residue, i.e., 4.01 and 28.51% respectively along with 31.89 and 33.57% RAL loading efficiency made MSNs more attractive and applicable. Eventually, in vitro release study exhibited higher RAL release in acidic media for extended time periods confirming successful formation of pH responsive nanoparticle having controlled release property. Conclusively potential of designed nanosystem to serve efficient anti-cancer remedy was confirmed by superior behaviour of chitosan grafted MSN towards MCF-7 cells with supreme hemocompatibility.

Formulation and In Vitro Characterization of Bioactive Mesoporous Silica with Doxorubicin and Metronidazole Intended for Bone Treatment and Regeneration

The purpose of this study was to evaluate the surface mineralization activity and in vitro drug behavior potential of two forms of mesoporous silica: powder and granulate. Ordered mesoporous SiO₂ powder was synthesized by surfactant-assisted sol-gel process using tetraethoxysilane as a silica precursor and hexadecyltrimethylammonium bromide as the structure-directing agent. The granulate was prepared using silica powder and ethyl cellulose as a binding agent. Metronidazole (MT)-an anti-inflammatory substance and doxorubicin hydrochloride (ChD)-an anti-cancer drug were chosen as drug models for delivery studies. The results of structural characteristic studies, utilizing transmission electron microscope (TEM) and scanning electron microscope (SEM) images, powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and nitrogen adsorption-desorption (BET) measurements, show that obtained materials have two-dimensional hexagonal p6mm symmetry, high specific surface area, narrow pore size, and a satisfactory mineralization behavior in the simulated body solution (SBF, pH = 7.4). The release rate of drugs depends upon the structural features of the drug molecules and the form of the carrier material. Of both the drugs analyzed, faster release was observed for small MT molecules characterized by weaker interactions with the carrier. In addition, the slower drug release was observed with granulate form due to increased diffusion barrier for drugs. Obtained results prove that the MT/ChD-loaded silica formulations could be attractive materials for filling bone defects and for local delivery systems.

Mesoporous silica materials: From physico-chemical properties to enhanced dissolution of poorly water-soluble drugs

New approaches in pharmaceutical chemistry have resulted in more complex drug molecules in the quest to achieve higher affinity to their targets. However, these 'highly active' drugs can also suffer from poor water solubility. Hence, poorly water soluble drugs became a major challenge in drug formulation, and this problem is increasing, as currently about 40 of the marketed drugs and 90% of drug candidates are classified as poorly water soluble. Various approaches exist to circumvent poor water solubility and poor dissolution rate in aqueous environment, however, each having disadvantages and certain limitations. Recently, mesoporous silica materials (MSMs) have been proposed to be used as matrices for enhancing the apparent solubility and dissolution rate of different drug molecules. MSMs are ideal candidates for this purpose, as silica is a "generally regarded as safe" (GRAS) material, is biodegradable, and can be readily surface-modified in order to optimize drug loading and subsequent release in the human body. The major advantage of mesoporous silica as drug delivery systems (DDSs) for poorly water soluble drugs lies in their pore size, pore morphology, and versatility in alteration of the surface groups, which can result in optimized interactions between a drug candidate and MSM carrier by modifying the pore surfaces. Furthermore, the drug of interest can be loaded into these pores in a preferably amorphous state, which can increase the drug dissolution properties dramatically. The highlights of this review include a critical discussion about the modification of the physico-chemical properties of MSMs and how these physico-chemical modifications influence the drug loading and the subsequent dissolution of poorly water soluble drugs. It aims to further promote the use of MSMs as alternative strategy to common methods like solubility enhancement by cyclodextrins, micronization, or microemulsion techniques. This review can provide guidance on how to tailor MSMs to achieve optimized drug loading and drug dissolution.

Hypocrellin B and nano silver loaded polymeric nanoparticles: Enhanced generation of singlet oxygen for improved photodynamic therapy

A nanoparticulate photodynamic approach was employed with an objective to achieve enhanced production of singlet oxygen (¹O₂), for the management of posterior segment eye diseases like age related macular degeneration. The hypocrellin B (HB) loaded poly lactide-co-glycolide nanoparticle formulations were incorporated with nano silver (HBS-NPs). The optimized HBS-NPs contained 2.60±0.06mg/mL of HB and showed (i) 135.6 to 828.2nm size range, and (ii) negative zeta potential with a narrow polydispersity index. The DSC thermograms suggested the amorphous nature of HB inside the HBS-NPs. With the average encapsulation efficiency of 92.9±1.79%, the drug release from the HBS-NPs followed a biphasic pattern with an initial burst of 3.50% during first 8h followed by a sustained release of 47.82% within 3days. The interaction between nano silver and HB as assessed by the increase in spectral intensity of Raman spectrum demonstrates that HB may be attached over the nano silver. Generation of reactive oxygen species (ROS) by HBS-NPs was significantly higher than that of HB/HB-NPs. The singlet oxygen generating efficiency assessed using EPR spectrometer follows the order of nano silver>HB-NPs>pure HB drug solution>HBS-NPs. The HBS-NPs had a concentration and time dependent phototoxicity on A549 (human adeno lung carcinoma) cells in the presence of light providing a superior phototoxic effect (82.2% at 50μM) at 2h irradiation. The CAM treated with HBS-NPs showed a significant anti-angiogenic effect compared to a blank formulation. In vivo biodistribution studies revealed that intravenous administration of HBS-NPs lead into significant exposure to the posterior segment of the eye. This proof of principle study demonstrates that HB based nanoparticles may be a valuable new tool for application in ocular photodynamic therapy for the treatment of AMD in future.

Methotrexate Nanoparticles Prepared with Codendrimer from Polyamidoamine (PAMAM) and Oligoethylene Glycols (OEG) Dendrons: Antitumor Efficacy in Vitro and in Vivo

The novel methotrexate-loaded nanoparticles (MTX/PGD NPs) prepared with amphiphilic codendrimer PGD from polyamidoamine and oligothylene glycol dendrons were obtained via antisolvent precipitation method augmented by ultrasonication. Based on the excellent hydrophility of PGD, the drug-loaded nanoparticles could be investigated easily with the high drug-loading content (~85.2%, w/w). The MTX/PGD NPs possessed spherical morphology, nanoscaled particle size (approximately 182.4 nm), and narrow particle size distribution. Release of MTX from MTX/PGD NPs showed a sustained release manner and completed within 48 h. Hemolytic evaluation indicated MTX/PGD NPs presented good blood compatibility, and the cytotoxicity of nanoparticles against breast cancer cells in vitro, biodistribution in tumor tissue, and antitumor efficacy in vivo were enhanced significantly compared to MTX injection. According to the higher drug-loading content, enhanced antitumor efficacy, and appropriate particle size, MTX/PGD NPs as the drug delivery systems could have potential application for cancer chemotherapy in clinic.

A series of codendrimers from polyamidoamine (PAMAM) and oligoethylene glycols (OEG) dendrons as drug carriers: the effect of OEG dendron decoration degree

To evaluate the effect of OEG dendron decoration degree and find a suitable carrier, a series of codendrimers are prepared and utilized to transport methotrexate.

Sugarcane bagasse lignin, and silica gel and magneto-silica as drug vehicles for development of innocuous methotrexate drug against rheumatoid arthritis disease in albino rats

The present study clarifies co-therapy action of deliveries from their textural changes point of view. Methotrexate (MTX) was immobilized onto biodegradable lignin, silica gel and iron/silica nanocomposite. Loaded-MTX was i.p. injected into albino rats at doses of 0.25 and 0.5mg/kg/week for 2.5months, after which spleen, liver, testes and knee joint tissues were collected for tests. IFN-γ and IL-17A mRNA gene expressions in spleen in all biological samples were determined by RT-PCR. Physicochemical features of drug carriers were monitored by XRD, BET-PSD, SEM and TEM. Drug inflammatory-site targeting was found to be closely related to the physico-features of deliverers. The interlayered lignin of micro- and meso-pore channels directed MTX toward concealed infected cells in liver and testes tissues, while meso-structured silica flacks satisfied by gathering MTX around knee joints. The magneto-silica nanocomposite targeted MTX toward spleen tissue, which is considered as a lively factory for the production of electron rich compounds.

Dasatinib

Dasatinib (Sprycel®), a second-generation TKI, has been shown to be effective as an anticancer drug in the treatment of patients with chronic myeloid leukemia or Philadelphia chromosome-positive acute lymphoblastic leukemia who are resistant or intolerant to imatinib. Several methods of gefitinib synthesis are included in this review. UV spectroscopy of dasatinib showed a λmax of approximately 320-330nm, and IR spectroscopy principal peaks were observed at 3418 (NH), 3200 (OH), 1620 (CO), 1582 (CC and CN), 1513 (CHCH) cm(-1). Characteristic NH peaks were observed in nuclear magnetic resonance (NMR) spectroscopy at 11.47 and 9.88ppm. The molecular mass was observed at m/z=487.3((35)Cl) and 488.9((37)Cl) (molecular weight=487.15) and the fragmentation pattern was studied using ion trap mass spectrometry. In addition, different analytical methods for determination of dasatinib are also described in this review. Pharmacokinetically, dasatinib is rapidly absorbed after oral administration where the solubility is dependent on pH. Dasatinib extensively binds to human plasma proteins by approximately 96%. In leukemic patient, the calculated apparent volume of distribution for dasatinib was 2502L and the estimated elimination half-life was approximately 3-5h. Dasatinib is metabolized in humans markedly by CYP3A4 to active metabolites and by phase II drug-metabolizing enzymes, such as UDP glucuronosyltransferase. Dasatinib is mainly eliminated via the feces (85%), of which relatively small amount of dasatinib is excreted unchanged as intact drug (19%). Most of the adverse effects associated with dasatinib therapy are mild to moderate in severity and are usually reversible and manageable with appropriate intervention, such as cardiac failure, hypertension, and coronary artery disease.

Anticancer drug-incorporated layered double hydroxide nanohybrids and their enhanced anticancer therapeutic efficacy in combination cancer treatment

OBJECTIVE

Layered double hydroxide (LDH) nanoparticles have been studied as cellular delivery carriers for anionic anticancer agents. As MTX and 5-FU are clinically utilized anticancer drugs in combination therapy, we aimed to enhance the therapeutic performance with the help of LDH nanoparticles.

METHOD

Anticancer drugs, MTX and 5-FU, and their combination, were incorporated into LDH by reconstruction method. Simply, LDHs were thermally pretreated at 400°C, and then reacted with drug solution to simultaneously form drug-incorporated LDH. Thus prepared MTX/LDH (ML), 5-FU/LDH (FL), and (MTX + 5-FU)/LDH (MFL) nanohybrids were characterized by X-ray diffractometer, scanning electron microscopy, infrared spectroscopy, thermal analysis, zeta potential measurement, dynamic light scattering, and so forth. The nanohybrids were administrated to the human cervical adenocarcinoma, HeLa cells, in concentration-dependent manner, comparing with drug itself to verify the enhanced therapeutic efficacy.

CONCLUSION

All the nanohybrids successfully accommodated intended drug molecules in their house-of-card-like structures during reconstruction reaction. It was found that the anticancer efficacy of MFL nanohybrid was higher than other nanohybrids, free drugs, or their mixtures, which means the multidrug-incorporated LDH nanohybrids could be potential drug delivery carriers for efficient cancer treatment via combination therapy.

Synthesis, characterization and pH-controllable methotrexate release from biocompatible polymer/silica nanocomposite for anticancer drug delivery

The objective of this study was to develop pH-responsive silica nanoparticles by imidazole-based ionic liquid for controlled release of methotrexate. In this article, we synthesized pH-responsive cationic silica nanoparticles by graft copolymerization of vinyl functionalized silica nanoparticles and methacrylic acid (MAA) monomer. Imidazole-based ionic liquid (Im-IL) was verified by (1)HNMR and Fourier-transform infrared (FTIR) spectroscopy. The synthesized functionalized silica particles were characterized and confirmed by various technologies including the scanning electron microscopy (SEM), the infrared spectroscopy (IR) and the thermogravimetric analysis (TGA). SEM results reveal the uniformity in size/shape of silica particles. This nanosystem is modified for targeted delivery of an anticancer agent methotrexate. The nanocomposite-MTX complex was formed at physiological pH (7.4) due to the electrostatic interactions between anionic carboxylic group of MTX molecules and cationic rings in carrier, while, the release of which can be achieved through the cleavage of the nanocomposite-MTX complex by protonation of carboxyl groups in the MTX segment that are sensitive to variations in external pH at weak acidic conditions. FT-IR spectroscopy showed the presence of light interactions between the silicate silanols and the drug. MCF7 cells were incubated with the MTX-free nanocomposite and MTX-loaded nanocomposite at various concentrations for 24, 48 and 72 h, and the data showed that the nanocomposites themselves did not affect the growth of MCF7 cells. Antitumor activity of the MTX-loaded nanocomposites against the cells was kept over the whole experiment process. The results showed that the MTX could be released from the fibers without losing cytotoxicity.

Drug loading and release on tumor cells using silk fibroin-albumin nanoparticles as carriers

Polymeric and biodegradable nanoparticles are frequently used in drug delivery systems. In this study silk fibroin-albumin blended nanoparticles were prepared using the desolvation method without any surfactant. These nanoparticles are easily internalized by the cells, reside within perinuclear spaces and act as carriers for delivery of the model drug methotrexate. Methotrexate loaded nanoparticles have better encapsulation efficiency, drug loading ability and less toxicity. The in vitro release behavior of methotrexate from the nanoparticles suggests that about 85% of the drug gets released after 12 days. The encapsulation and loading of a drug would depend on factors such as size, charge and hydrophobicity, which affect drug release. MTT assay and conjugation of particles with FITC demonstrate that the silk fibroin-albumin nanoparticles do not affect the viability and biocompatibility of cells. This blended nanoparticle, therefore, could be a promising nanocarrier for the delivery of drugs and other bioactive molecules.

Mucosa-plate for direct evaluation of mucoadhesion of drug carriers

The method to prepare mucosa-plates, glass slides covalently coated with mucin, is demonstrated. The use of the plate to evaluate mucoadhesion of nanocarriers made from different four polymeric materials, N-succinylchitosan (NS-chitosan), alginate (ALG), ethylcellulose (EC), and a blend of EC and methylcellulose (EC/MC), was demonstrated. While different mucoadhesion of the four carriers could be detected using mucosa-plate, the conventional viscosity measurement could not differentiate their mucin-binding ability. ALG and NS-chitosan nanospheres showed the best attachment to the mucosa-plate compared to the EC/MC and EC spheres. Capsaicin, a model hydrophobic drug, was loaded into the carriers and the ability of the different polymeric carriers to retain capsaicin at the stomach tissue was compared using an ex vivo fresh porcine stomach assay. Ability to retain capsaicin at the stomach tissue correlated well with binding affinity toward the mucosa-plate and the loading capacity of the carriers.