Tamoxifen citrate encapsulated sustained release liposomes: preparation and evaluation of physicochemical properties

Studies on PVP-Based Hydrogel Polymers as Dressing Materials with Prolonged Anticancer Drug Delivery Function

Tamoxifen is a well-known active substance with anticancer activity. Currently, many investigations are performed on the development of carriers that provide its effective delivery. Particular attention is directed toward the formation of cyclodextrin-drug complexes to provide prolonged drug delivery. According to our knowledge, carriers in the form of polyvinylpyrrolidone (PVP)/gelatin-based hydrogels incorporated with β-cyclodextrin-tamoxifen complexes and additionally modified with nanogold have not been presented in the literature. In this work, two series of these materials have been synthesized-with tamoxifen and with its complex with β-cyclodextrin. The process of obtaining drug carrier systems consisted of several stages. Firstly, the nanogold suspension was obtained. Next, the hydrogels were prepared via photopolymerization. The size, dispersity and optical properties of nanogold as well as the swelling properties of hydrogels, their behavior in simulated physiological liquids and the impact of these liquids on their chemical structure were verified. The release profiles of tamoxifen from composites were also determined. The developed materials showed swelling capacity, stability in tested environments that did not affect their structure, and the ability to release drugs, while the release process was much more effective in acidic conditions than in alkaline ones. This is a benefit considering their use for anticancer drug delivery, due to the fact that near cancer cells, there is an acidic environment. In the case of the composites containing the drug-β-cyclodextrin complex, a prolonged release process was achieved compared to the drug release from materials with unbound tamoxifen. In terms of the properties and the composition, the developed materials show a great application potential as drug carriers, in particular as carriers of anticancer drugs such as tamoxifen.

Mechanistic Approach of Nano Carriers for Targeted in Cancer Chemotherapy: A Newer Strategy for Novel Drug Delivery System

The application of nanomedicine represents an innovative approach for the treatment in the modern field of cancer chemotherapy. In the present research work, tamoxifen citrate loaded nanolipid vesicles were prepared conjugated with phosphoethanolamine as the linker molecule, and the specific antibody was tagged with the linker molecule on the bilayer surface of the vesicles. The main objective of this study is to determine the efficacy and biological behavior of antibody conjugated nanoliposome in breast cancer cell lines. Percentage of drug loading and loading efficiency was done and their results were compared to theoretical drug loading. The average diameter of those vesicles was within the 100 nm range, which is revealed in FESEM and TEM images and their lamellarity was observed in cryo-TEM images. The hydrodynamic diameter was done by particle size analysis and the surface charge was determined by the zeta potential parameter. Predominant cellular uptake was observed for antibody conjugated nanolipid vesicles in MCF-7 and MDA-MB-453 human breast cancer cell lines. A cellular apoptosis assay was conducted by flow cytometer (FACS). All experimental data would be more beneficial for the treatment of breast cancer chemotherapy. Further studies are warranted to investigate the efficacy and safety of antibody conjugated nanolipid vesicles in vivo for breast cancer animal model.

Preparation of Liposomal Raloxifene-Graphene Nanosheet and Evaluation of Its In Vitro Anticancer Effects

BACKGROUND

In current years, researchers have shown their prime interest in developing multifunctional drug delivery systems, especially against cancers, for effective anticancer outcomes.

METHODOLOGY

Raloxifene (RLX) loaded liposomal-graphene nanosheet (GNS) was developed. The novelty of this work was to enhance the solubilization of RLX and improvement of its bioavailability in the disease area. So, the selection of optimized formula design of experiment was implemented which produced the desired formula with the particle size of 156.333 nm. Further, encapsulation efficiency, in vitro release, and thermodynamic stability of optimized formulation were evaluated. The optimized formulation exhibited prolonged release of RLX for a longer period of 24 h, which can minimize the dose-related toxicity of the drug. Furthermore, optimized formulation demonstrated remarkable thermodynamic stability in terms of phase separation, creaming, and cracking.

RESULTS

The cytotoxicity study on the A549 cell line exhibited significant (P < .05) results in favor of optimized formulation than the free drug. The apoptotic activity was carried out by Annexin V staining and Caspase 3 analysis, which demonstrated remarkable promising results for optimized liposomal formulation.

CONCLUSION

From the findings of the study, it can be concluded that the novel optimized liposomal formulation could be pondered as a novel approach for the treatment of lung cancer.

Experimental Design Supported Liposomal Aztreonam Delivery: In Vitro Studies

Purpose: The present study focuses on a systemic approach to develop liposomal aztreonam as a promising dosage form for inhalation therapy in the treatment of pneumonia and explores the in-vitro antimicrobial and cell uptake efficacy. Methods: Liposomes were prepared by ethanol injection method using the lipids - soya phosphatidylcholine (SP) and cholesterol (CH). A central composite design (CCD) was employed to optimize the lipid composition to evaluate the effect on vesicle size, zeta potential and entrapment efficiency of the formulation. A numerical and graphical optimization was carried out to predict the optimized blend. The optimized formulation was characterized for vesicle size, surface charge, encapsulation, surface morphology, differential scanning calorimetry (DSC), powder X Ray Diffraction (PXRD), thermogravimetric analysis (TGA), in vitro diffusion, accelerated stability studies, antimicrobial studies on Pseudomonas aeruginosa NCIM 2200 and in vitro cell uptake studies. Results: The optimized formulation was found to have a particle size of 144 nm, a surface charge of -35 mV, with satisfactory drug entrapment. The surface morphology study proved the formation of nanosized vesicles. The drug release from liposomal matrix was biphasic in nature. The solid-state study revealed the reason for good encapsulation of drug. The moisture retention capacity was found to be minimum. The anti-microbial study revealed the potential antibacterial activity of the optimized formulation over the pure drug. The formulation was found to be safe on the epithelial cells and showed a marked increase in cellular uptake of aztreonam in a lipid carrier. Conclusion: It can be concluded that the optimized liposomal aztreonam could be considered as a promising approach for the delivery of aztreonam through inhalation.

Formulation, characterization, and cellular toxicity assessment of tamoxifen-loaded silk fibroin nanoparticles in breast cancer

Silk fibroin (SF) is a natural polymeric biomaterial that is widely adopted for the preparation of drug delivery systems. Herein, we aimed to fabricate and characterize SF nanoparticles loaded with the selective estrogen receptor modulator; tamoxifen citrate (TC-SF-NPs) and to assess their in vitro efficacy against breast cancer cell lines (MCF-7 and MDA-MB-231). TC-loaded SF-NPs were characterized for particle size, morphology, entrapment efficiency, and release profile. In addition, we examined the in vitro cytotoxicity of TC-SF-NPs against human breast cancer cell lines and evaluated the anticancer potential of TC-SF-NPs through apoptosis assay and cell cycle analysis. Drug-loaded SF-NPs showed an average particle size of 186.1 ± 5.9 nm and entrapment efficiency of 79.08%. Scanning electron microscopy (SEM) showed the nanoparticles had a spherical morphology with smooth surface. Tamoxifen release from SF-NPs exhibited a biphasic release profile with an initial burst release within the first 6 h and sustained release for 48 h. TC-SF-NPs exerted a dose-dependent cytotoxic effect against breast cancer cell lines. In addition, flow cytometry analysis revealed that cells accumulate in G₀/G₁ phase, with a concomitant reduction of S- and G₂-M-phase cells upon treatment with TC-SF-NPs. Consequently, the potent anticancer activities of TC-SF-NPs against breast cancer cells were mainly attributed to the induction of apoptosis and cell cycle arrest. Our results indicate that SF nanoparticles may represent an attractive nontoxic nanocarrier for the delivery of anticancer drugs.

Mometasone furoate-loaded aspasomal gel for topical treatment of psoriasis: formulation, optimization, in vitro and in vivo performance

BACKGROUND

Present investigation was aimed to develop aspasomal gel of Mometasone Furoate for the treatment of Psoriasis that are biologically active and deliver drug at controlled rate and decrease dosing frequency.

METHODS

The vesicles were fabricated using film hydration method and optimized using 32 factorial Design. Prepared formulations were evaluated for percent drug loading, vesicle size, Zeta potential, polydispersity index and morphological studies. Gel was prepared using carbopol by loading optimized drug loaded asposomes and was evaluated for drug content, pH, viscosity and spreadability. The drug release study from the gel was done using dialysis membrane and goat skin. Anti- oxidant potency of the prepared aspasomal gel was determined by Ferric Reducing Assay whereas, in-vivo performance for inflammation and skin irritation was carried out using Wistar rats.

RESULTS

Optimized aspasomes demonstrated desired properties for entrapment efficiency (74.72 ± 1.8), vesicle size (282.9 ± 1.7), polydispersity index (0.2), zeta potential (-20.2 mV) with spherical shape. The results recorded for drug release from the optimized aspasomal gel exhibited sustained release (24h) compared to the marketed cream (5h). Depot formation of Mometasone furoate loaded aspasomal gel in the epidermis was confirmed by ex vivo skin penetration study by using fluorescent marker. In-vivo study revealed no any irritation and inflammation to the skin promoting drug delivery system to treat psoriasis.

CONCLUSION

In conclusion, Mometasone furoate loaded aspasomal gel releases the drug for longer duration of time and reduce dosing frequency, providing the new dimension for the treatment of psoriasis.

Novel Tamoxifen Nanoformulations for Improving Breast Cancer Treatment: Old Wine in New Bottles

Breast cancer (BC) is one of the leading causes of death from cancer in women; second only to lung cancer. Tamoxifen (TAM) is a hydrophobic anticancer agent and a selective estrogen modulator (SERM), approved by the FDA for hormone therapy of BC. Despite having striking efficacy in BC therapy, concerns regarding the dose-dependent carcinogenicity of TAM still persist, restricting its therapeutic applications. Nanotechnology has emerged as one of the most important strategies to solve the issue of TAM toxicity, owing to the ability of nano-enabled-formulations to deliver smaller concentrations of TAM to cancer cells, over a longer period of time. Various TAM-containing-nanosystems have been successfully fabricated to selectively deliver TAM to specific molecular targets found on tumour membranes, reducing unwanted toxic effects. This review begins with an outline of breast cancer, the current treatment options and a history of how TAM has been used as a combatant of BC. A detailed discussion of various nanoformulation strategies used to deliver lower doses of TAM selectively to breast tumours will then follow. Finally, a commentary on future perspectives of TAM being employed as a targeting vector, to guide the delivery of other therapeutic and diagnostic agents selectively to breast tumours will be presented.

Synthesis, Characterization, and Drug Delivery Application of Self-assembling Amphiphilic Cyclodextrin

The main aim of the research was to synthesize amphiphilic cyclodextrin (AMCD) by substituting C12 alkyl chain to a β-cyclodextrin (βCD) in a single step and to study its self-assembly in an aqueous medium. The drug delivery application of the AMCD was also evaluated by encapsulating tamoxifen citrate as a model hydrophobic drug. AMCD was able to self-assemble in aqueous media, forming nanovesicles of size < 200 nm, capable of encapsulating tamoxifen citrate (TMX). Molecular docking and MD simulation studies revealed the interaction between TMX and AMCD which formed a stable complex. TEM and AFM studies showed that nanovesicles were perfectly spherical having a smooth surface and a theoretical AMCD bilayer thickness of ~ 7.2 nm as observed from SANS studies. XRD and DSC studies revealed that TMX was amorphized and molecularly dispersed in AMCD bilayer which was released slowly following Fickian diffusion. AMCD has excellent hemocompatibility as opposed to βCD and no genotoxicity. IC₅₀ of TMX against MCF-7 cell lines was significantly reduced from 11.43 to 7.96 μg/ml after encapsulation in nanovesicle because of nanovesicles being endocytosed by the MCF-7 cells. AMCD was well tolerated by IV route at a dose of > 2000 mg/kg in rats. Pharmacokinetic profile of TMX after encapsulation was improved giving 3-fold higher AUC; extended mean residence time is improving chances of nanovesicle to extravasate in tumor via EPR effect.

Preparation, characterization and in-vivo evaluation of microemulsions containing tamoxifen citrate anti-cancer drug

The aim of this study was to prepare and characterize a new nanocarrier for oral delivery of tamoxifen citrate (TMC) as a lipophilic oral administrated drug. This drug has low oral bioavailability due to its low aqueous solubility. To enhance the solubility of this drug, the microemulsion system was applied in form of oil-in-water. Sesame oil and Tween 80 were used as drug solvent oil and surfactant, respectively. Two different formulations were prepared for this purpose. The first formulation contained edible glycerin as co-surfactant and the second formulation contained Span 80 as a mixed surfactant. The results of characterization showed that the mean droplet size of drug-free samples was in the range of 16.64-64.62nm with a PDI value of <0.5. In a period of 6months after the preparation of samples, no phase sedimentation was observed, which confirmed the high stability of samples. TMC with a mass ratio of 1% was loaded in the selected samples. No significant size enlargement and drug precipitation were observed 6months after drug loading. In addition, the drug release profile at experimental environments in buffers with pH=7.4 and 5.5 showed that in the first 24h, 85.79 and 100% of the drug were released through the first formulation and 76.63 and 66.42% through the second formulation, respectively. The in-vivo results in BALB/c female mice showed that taking microemulsion form of drug caused a significant reduction in the growth rate of cancerous tumor and weight loss of the mice compared to the consumption of commercial drug tablets. The results confirmed that the new formulation of TMC could be useful for breast cancer treatment.

Flurbiprofen-loaded stealth liposomes: studies on the development, characterization, pharmacokinetics, and biodistribution

Flurbiprofen (FP) is a phenyl alkanoic acid derivative and a family of non-steroidal anti-inflammatory drug used in the treatment of arthritis. The aim of this study was to prepare a new parenteral formulation for FP that can prolong the biologic half-life of the drug, improve its therapeutic efficacy, and reduce its associated side effects targeting the inflammation due to arthritis. PEG-anchored (stealth) and non-PEG-anchored liposomes were prepared by thin film hydration technique followed by extrusion cycle and characterized for in vitro and in vivo. Stealth liposomes (SLs) exhibited increase in percent encapsulation efficiency (68%) and percent drug retention during release studies in 24 h (71%) with good stability for a period of 1 month at -20°C and 4°C (refrigerated temperature) compared with other liposomes. The maximum percent edema inhibition (58%) and significant analgesic effect of 13 s were determined for SLs. The pharmacokinetic parameters after i.v. administration to arthritis induced rats were determined and compared with non-SLs. The marked differences produced for SLs over those of non-SL (conventional) formulations with an increase in area under plasma concentration time curve, t 1/2, mean residence time, and reduced clearance. The drug localization in liver, spleen, and kidney were significantly higher for non-PEGylated liposomes than the SLs. Nearly 3-fold increase in drug concentration was measured in arthritic paw when compared with the other liposome formulations. Thus SLs may help to increase the therapeutic efficacy of FP by increasing the targeting potential at the site of action.

Transdermal drug delivery of paroxetine through lipid-vesicular formulation to augment its bioavailability

Paroxetine (PAX) is the most potent serotonin reuptake blocker antidepressant clinically available. This study is aimed to reduce the side effects accompanied with the initial high plasma concentration after oral administration of PAX and fluctuations in plasma levels and also to decrease the broad metabolism of the drug in the liver by developing and optimizing liposomal transdermal formulation of PAX in order to improve its bioavailability. PAX liposomes were prepared by reverse phase evaporation technique using lecithin phosphatidylcholine (LPC), cholesterol (CHOL) and drug in different molar ratios. The prepared liposomes were characterized for size, shape, entrapment efficiency and in vitro drug release. The studies demonstrated successful preparation of PAX liposomes. The effect of using different molar ratios of (LPC:CHOL) on entrapment efficiency and on drug release was studied. Liposomes showed percentage entrapment efficiency (%EE) of 81.22 ± 3.08% for optimized formula (F5) which composed of (LPC:CHOL, 7:7) and 20mg of PAX, with average vesicle size of 220.53 ± 0.757 nm. The selected formula F5 (7:7) was incorporated in gel bases of HPMC-E4M (2%, 4%, and 6%). The selected formula of PAX liposomal gel of HPMC-E4M (2% and 4%) were fabricated in the reservoir type of transdermal patches and evaluated through in vitro release. After that the selected formula of PAX liposomal gel transdermal patch was applied to rabbits for in vivo bioavailability study in comparison with oral administration of the marketed PAX tablet. An HPLC method was developed for the determination of PAX in plasma of rabbits after transdermal patch application and oral administration of the marketed PAX tablets of 20mg dose. The intra- and inter-day accuracy and precision were determined as relative error and relative standard deviation, respectively. The linearity was assessed in the range of 5-200 ng/ml. Pharmacokinetic parameters were determined as the C(max) of PAX liposomal transdermal patch was found to be 92.53 ng/ml at t(max) of 12h and AUC(0-48) was 2305.656 ngh/ml and AUC(0-∞) was 3852.726 ngh/ml, compared to the C(max) of 172.35 ng/ml after oral administration of the marketed PAX tablet with t(max) of 6h and AUC(0-24) was 1206.63 ngh/ml and AUC(0-∞) was 1322.878 ngh/ml. These results indicate improvement of bioavailability of the PAX after liposomal transdermal patch application and sustaining of the therapeutic effects compared to oral administration.

Transfersomes: a novel vesicular carrier for enhanced transdermal delivery of sertraline: development, characterization, and performance evaluation

The aim of the present study was to investigate transfersomes as a transdermal delivery system for the poorly soluble drug, sertraline, in order to overcome the troubles associated with its oral delivery. Different transfersomal formulations were prepared with non-ionic surfactant (span 80), soya lecithin, and carbopol 940 by the rotary evaporation sonication method. The prepared formulations were characterized for light microscopy, particle size analysis, drug entrapment, turbidity, drug content, rheological studies, in vitro release, ex vivo permeation, and stability studies. The optimized formulation was evaluated for in vivo studies using the modified forced swim model test. FTIR studies showed compatibility of the drug with excipients. The result revealed that sertraline in all of the formulations was successfully entrapped with uniform drug content. Transfersomal gel containing 1.6% of the drug and 20% of span 80 was concluded to be the optimized formulation (EL-SP4), as it showed maximum drug entrapment (90.4±0.15%) and cumulative percent drug release(73.8%). The ex vivo permeation profile of EL-SP4 was compared with the transfersomal suspension, control gel, and drug solution. The transfersomal gel showed a significantly higher (p<0.05) cumulative amount of drug permeation and flux along with lower lag time than the drug solution and drug gel. It also owed to better applicability due to the higher viscosity imparted by the gel rather than the transfersomal suspension, and no skin irritation was observed. The modified forced swim test in mice revealed that the transfersomal gel had better antidepressant activity as compared to the control gel. Thus, the study substantiated that the transfersomal gel can be used as a feasible alternative to the conventional formulations of sertraline with advanced permeation characteristics for transdermal application.

Ribonuclease-Activated Cancer Prodrug

Cancer chemotherapeutic agents often have a narrow therapeutic index that challenges the maintenance of a safe and effective dose. Consistent plasma concentrations of a drug can be obtained by using a timed-release prodrug strategy. We reasoned that a ribonucleoside 3'-phosphate could serve as a pro-moiety that also increases the hydrophilicity of a cancer chemotherapeutic agent. Herein, we report an efficient route for the synthesis of the prodrug uridine 3'-(4-hydroxytamoxifen phosphate) (UpHT). UpHT demonstrates timed-released activation kinetics with a half-life of approximately 4 h at the approximate plasma concentration of human pancreatic ribonuclease (RNase 1). MCF-7 breast cancer cells treated with UpHT showed decreased proliferation upon co-incubation with RNase 1, consistent with the release of the active drug-4-hydroxytamoxifen. These data demonstrate the utility of a human plasma enzyme as a useful activator of a prodrug.

Cyclodextrin-based nanosponges: effective nanocarrier for tamoxifen delivery

The purpose of the present study was to develop Tamoxifen loaded β-cyclodextrin nanosponges for oral drug delivery. The three types of Tamoxifen loaded β-cyclodextrin nanosponges were synthesized by varying the molar ratios of β-cyclodextrin to carbonyldiimidazole as a crosslinker viz. 1:2, 1:4 and 1:8. The Tamoxifen nanosponge complex (TNC) with particle size of 400-600 nm was obtained by freeze drying method. Differential scanning calorimetry, Fourier transformed infra-red spectroscopy and X-ray powder diffraction studies confirmed the complexation of Tamoxifen with cyclodextrin nanosponge. AUC and Cmax of TNC formulation (1236.4 ± 16.12 µg · mL(-1) h, 421.156 ± 0.91 µg/mL) after gastric intubation were 1.44 fold and 1.38 fold higher than plain drug (856.079 ± 15.18 µg · mL(-1) h, 298.532 ± 1.15 µg/mL). Cytotoxic studies on MCF-7 cells showed that TNC formulation was more cytotoxic than plain Tamoxifen after 24 and 48 h of incubation.

Cancer Targeted Nanoparticles Specifically Induce Apoptosis in Cancer Cells and Spare Normal Cells

Curing cancer is the greatest challenge for modern medicine and finding ways to minimize the adverse effects caused by chemotherapeutic agents is of importance in improving patient’s physical conditions. Traditionally, chemotherapy can induce various adverse effects, and these effects are mostly caused by the non-target specific properties of the chemotherapeutic compounds. Recently, the use of nanoparticles has been found to be capable of minimizing these drug-induced adverse effects in animals and in patients during cancer treatment. The use of nanoparticles allows various chemotherapeutic drugs to be targeted to cancer cells with lower dosages. In addition to this, the use of nanoparticles also allows various drugs to be administered to the subjects by an oral route. Here, locked nucleic acid (LNA)-modified epithelial cell adhesion molecules (EpCAM), aptamers (RNA nucleotide), and nucleolin (DNA nucleotide) aptamers have been developed and conjugated on anti-cancer drug-loaded nanocarriers for specific delivery to cancer cells and spare normal cells. Significant amounts of the drug loaded nanocarriers (92 ± 6 %) were found to distribute to the cancer cells at the tumour site and more interestingly, normal cells were unaffected in vitro and in vivo. In this review, the benefits of using nanoparticle-coated drugs in various cancer treatments are discussed. Various nanoparticles that have been tried in improving the target specificity and potency of chemotherapeutic compounds are also described.