Comparison in purity and antitumor effect of brand and generic paclitaxel against human ovarian cancer cells by an in vitro experimental model

Context: The purity and the therapeutic effectiveness of the generic paclitaxel have not yet been examined and compared to the original brand form. Objective: This study aimed to compare the in vitro purity and biological effects of original brand form (Taxol) and a generic drug of paclitaxel. Materials and Methods: Purity was determined by high-performance liquid chromatography analysis, cell viability by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay, cell proliferation by clonogenic assay, morphology by Liu's staining, and cell cycle distribution by DNA histogram. Results: Taxol and generic paclitaxel shared similar high-performance liquid chromatography profiles with a major peak at the same retention time and ultraviolet spectrum. Generic paclitaxel inhibited the cell viability to an extent greater than Taxol. By assessing the IC₅₀, generic paclitaxel also exhibited a greater inhibitory activity on clonogenicity of human ovarian adenocarcinoma SKOV-3 cells. Although both generic paclitaxel and Taxol arrested SKOV-3 and ES-2 cells at G2/M phase with concurrent development of hypoploid and polyploid cells, Taxol treatment exhibited markedly less extent of these changes. Observation of cellular morphology revealed a greater amount of mitotic catastrophe-like and apoptotic cells in generic paclitaxel-treated cells than Taxol-treated cells. Discussion and Conclusion: The results suggest that generic paclitaxel may possess a greater cell death inducing capacity and clonogenicity inhibitory activity against ovarian cancer cells than the original brand Taxol of the same purity. We conclude that this experimental model for assessing the difference between generic and brand name drugs might be considered as a reference while determining their interchangeability and could be easily established in a hospital-based laboratory.     

Phospholipid-Tween 80 mixed micelles as an intravenous delivery carrier for paclitaxel

A novel mixed micelle made of Tween 80 and soybean phospholipids (S80) was prepared and used as the delivery system for paclitaxel (PTX), with the purpose of improving the stability, therapeutic index, and security of PTX in comparison with Taxol? injection. The micelle size, morphological features, dilution stability, and critical micelle concentration (CMC) were measured. The in vitro antitumor activity, pharmacokinetics, and hemolysis effect of the optimal PTX-loaded mixed micelles (PTX-M) were evaluated and compared with Taxol?. The results showed that PTX-M was more stable than Taxol? upon dilution. PTX-M had a higher antitumor efficacy against HeLa and A549 cells than that of Taxol?. The plasma AUC of PTX-M was 1.3-fold higher than that of Taxol? and the hemolysis test revealed that PTX-M was safe for intravenous injection. In conclusion, PTX-M had a higher dilution stability and antitumor efficacy than Taxol?, but significantly reduced the toxicity while improving the bioavailability of PTX. Therefore, Tween 80-S80 mixed micelles could be a promising drug carrier for intravenous administration of PTX.     

In vitro and in vivo evaluation of paclitaxel–lapatinib-loaded F127 pluronic micelles

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^®.     

Superior Intratumoral Penetration of Paclitaxel Nanodots Strengthens Tumor Restriction and Metastasis Prevention

Recently discovered intratumoral diffusion resistance, together with poor solubility and nontargeted distribution of chemotherapeutic drugs, has significantly impaired the performance of cancer treatments. By developing a well‐designed droplet‐confined/cryodesiccation‐driven crystallization approach, we herein report the successful preparation of nanocrystallites of insoluble chemotherapeutic drug paclitaxel (PTX) in forms of nanodots (NDs, ≈10 nm) and nanoparticles (NPs, ≈70 nm) with considerably high drug loading capacity. Superficially coated Pluronic F127 is demonstrated to endow the both PTX nanocrystallites with excellent water solubility and prevent undesired phagocyte uptake. Further decoration with tumor‐penetrating peptide iRGD, as expected, indiscriminatively facilitates tumor cell uptake in traditional monolayer cell culture model. On the contrary, distinctly enhanced performances in inward penetration and ensuing elimination of 3D multicellular tumor spheroids are achieved by iRGD‐NDs rather than iRGD‐NPs, revealing the significant influence of particle size variation in nanoscale. In vivo experiments verify that, although efficient tumor enrichment is achieved by all nanocrystallites, only the iRGD‐grafted nanocrystallites of ultranano size realize thorough intratumoral delivery and reach cancer stem cells, which are concealed inside the tumor core. Consequently, much strengthened restriction on progress and metastasis of orthotopic 4T1 mammary adenocarcinoma is achieved in murine model, in sharp contrast to commercial PTX formulation Taxol.     

Folate-conjugated polymer micelles for active targeting to cancer cells: preparation, in vitro evaluation of targeting ability and cytotoxicity

To obtain an active-targeting carrier to cancer cells, folate-conjugated stearic acid grafted chitosan oligosaccharide (Fa-CSOSA) was synthesized by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)-mediated coupling reaction. The substitution degree is 22.1%. The critical micelle concentrations (CMCs) of Fa-CSOSA were 0.017 and 0.0074?mg?ml(-1) in distilled water and PBS (pH?7.4), respectively. The average volume size range of Fa-CSOSA micelles was 60-120?nm. The targeting ability of Fa-CSOSA micelles was investigated against two kinds of cell lines (A549 and Hela), which have different amounts of folate receptors in their surface. The results indicated that Fa-CSOSA micelles presented a targeting ability to the cells (Hela) with a higher expression of folate receptor during a short-time incubation (<6?h). As incubation proceeded, the special spatial structure of the micelles gradually plays a main role in cellular internalization of the micelles. Good internalization of the micelles into both Hela and A549 cells was shown. Then, paclitaxel (PTX) was encapsulated into the micelles, and the content of PTX in the micelles was about 4.8% (w/w). The average volume size range of PTX-loaded micelles was 150-340?nm. Furthermore, the anti-tumor efficacy in vitro was investigated by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) method. The IC(50) of Taxol (a clinical formulation containing PTX) on A549 and Hela cells was 7.0 and 11.0?μg?ml(-1), respectively. The cytotoxicity of PTX-loaded micelles was improved sharply (IC(50) on A549: 0.32?μg?ml(-1); IC(50) on Hela: 0.268?μg?ml(-1)). This is attributed to the increased intracellular delivery of the drug. The Fa-CSOSA micelles that are presented may be a promising active-targeting carrier candidate via folate mediation.     

Folate-mediated solid–liquid lipid nanoparticles for paclitaxel-coated poly(ethylene glycol)

Background: As a promising anticancer drug, severe side-effects of current clinical formulations for paclitaxel have restricted its use, developing a better technical-economical formulation for paclitaxel delivery is needed. Method: In this study, the compound of folate-poly(ethylene glycol) (PEG)-phosphatidylethanolamine was synthesized and characterized with Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The solid-liquid lipid nanoparticle (SLLN) for paclitaxel modified with folate and poly(ethylene glycol) (folate-PEG-SLLN) was prepared and characterized. Morphology of folate-PEG-SLLN was examined by transmission electron microscopy. The particle size and zeta potential were performed by Zetapals. Encapsulation efficiency was analyzed by HPLC. The in vitro drug release of paclitaxel was investigated via membrane dialysis. The in vivo pharmacokinetics was measured with male Sprague-Dawley rats. Treatment efficiency was investigated with the mouse with sarcoma180 ascites tumor. Results: Paclitaxel loaded on the newly designed binary SLLN showed a longer and sustained in vitro releasing property. More importantly, S180 tumor-bearing mice treated with paclitaxel-loaded SLLN exhibited higher tumor inhibition rate, comparing with animals administered with paclitaxel injection alone (45.3% and 37.3%, respectively). Conclusion: The newly developed paclitaxel delivery system may have improved in vivo antitumor activity. The results demonstrated a great interest to use folate-mediated SLLN as a prospective drug delivery system for paclitaxel.     

PLGA 50:50 nanoparticles of paclitaxel: Development, in vitro anti-tumor activity in BT-549 cells and in vivo evaluation

Clinical administration of paclitaxel is hindered due to its poor solubility, which necessitates the formulation of novel drug delivery systems to deliver such extreme hydrophobic drug. To formulate nanoparticles which makes suitable to deliver hydrophobic drugs effectively (intravenous) with desired pharmacokinetic profile for breast cancer treatment; in this context in vitro cytotoxic activity was evaluated using BT-549 cell line. PLGA nanoparticles were prepared by emulsion solvent evaporation technique and evaluated for physicochemical parameters, in vitro anti-tumor activity and in vivo pharmacokinetic studies in rats. Particle size obtained in optimized formulation was <200?nm. Encapsulation efficiency was higher at polymer-to-drug ratio of 20:1. In vitro drug release exhibited biphasic pattern with initial burst release followed by slow and continuous release (15?days). In vitro anti-tumor activity of optimized formulation inhibited cell growth for a period of 168?h against BT-549 cells. AUC_(0???) and t _1/2 were found to be higher for nanoparticles with low clearance rate.     

In vitro-in vivo characterization of release modifying agents for parenteral sustained-release ketorolac formulation

One of the prerequisites for a parenteral preparation is that the excipients incorporated are biocompatible and biodegradable. In the present study hydrophilic and hydrophobic excipients were investigated for developing an intramuscular sustained-release formulation of ketorolac. Kollidon® 17 PF, Peceol (glyceryl monooleate), and castor oil were chosen as the potential release-retarding agents, each with a distinct mechanism of action. They were evaluated by in vitro drug-release profiles and in vivo pharmacodynamic and pharmacokinetic study in mice. Cumulative drug release was determined for standard and test formulations in modified Franz diffusion cell. Pharmacodynamic parameter, T = 70% response of peak analgesic response, was used to compare the performance of test formulations. Based on pharmacodynamic/pharmacokinetic correlation in the animal studies, Css_max and Css_min of 51.39 and 30.0 µg/mL, respectively, were determined and considered as performance markers for pharmacokinetic evaluation of test formulations. The study suggested that the sustained-release capability of glyceryl monooleate was maximum followed by that of castor oil and Kollidon 17 PF, when compared to conventional ketorolac tromethamine formulation. It was inferred that water soluble excipient, though, showed release retarding property in vitro but could not maintain it in the in vivo environment. Glyceryl monooloeate-based formulation produced the most favorable drug blood concentration vs. time profile.     

Development of a liposome microbicide formulation for vaginal delivery of octylglycerol for HIV prevention

The feasibility of using a liposome drug delivery system to formulate octylglycerol (OG) as a vaginal microbicide product was explored. A liposome formulation was developed containing 1% OG and phosphatidyl choline in a ratio that demonstrated in vitro activity against Neisseria gonorrhoeae, HSV-1, HSV-2 and HIV-1 while sparing the innate vaginal flora, Lactobacillus. Two conventional gel formulations were prepared for comparison. The OG liposome formulation with the appropriate OG/lipid ratio and dosing level had greater efficacy than either conventional gel formulation and maintained this efficacy for at least 2 months. No toxicity was observed for the liposome formulation in ex vivo testing in a human ectocervical tissue model or in vivo testing in the macaque safety model. Furthermore, minimal toxicity was observed to lactobacilli in vitro or in vivo safety testing. The OG liposome formulation offers a promising microbicide product with efficacy against HSV, HIV and N. gonorrhoeae.     

Novel surface modified polymer–lipid hybrid nanoparticles as intranasal carriers for ropinirole hydrochloride: in vitro, ex vivo and in vivo pharmacodynamic evaluation

Here we report fabrication and evaluation of novel surface modified polymer–lipid hybrid nanoparticles (PLN) as robust carriers for intranasal delivery of ropinirole hydrochloride (ROPI HCl). Sustained release, avoidance of hepatic first pass metabolism, and improved therapeutic efficacy are the major objectives of this experiment. PLN were fabricated by emulsification-solvent diffusion technique and evaluated for physicochemical parameters, in vitro mucoadhesion, in vitro diffusion, ex vivo permeation, mucosal toxicity and stability studies. Box-Behnken experimental design approach has been employed to assess the influence of two independent variables, viz. surfactant (Pluronic F-68) and charge modifier (stearylamine) concentration on particle size, ζ-potential and entrapment efficiency of prepared PLN. Numerical optimization techniques were used for selecting optimized formulation sample, further confirmed by three dimensional response surface plots and regression equations. Results of ANOVA demonstrated the significance of suggested models. DSC and SEM analysis revealed the encapsulation of amorphous form of drug into PLN system, and spherical shape. PLN formulation had shown good retention with no severe signs of damage on integrity of nasal mucosa. Release pattern of drug-loaded sample was best fitted to zero order kinetic model with non-Fickian super case II diffusion mechanism. In vivo pharmacodynamic studies were executed to compare therapeutic efficacy of prepared nasal PLN formulation against marketed oral formulation of same drug. In summary, the PLN could be potentially used as safe and stable carrier for intranasal delivery of ROPI HCl, especially in treatment of Parkinson’s disease.     

Development and in vitro evaluation of a nanoemulsion for transcutaneous delivery

Objective: The purpose of this study is to develop a nanoemulsion formulation for its use as a transcutaneous vaccine delivery system.

Materials and methods: With bovine albumin-fluorescein isothiocyanate conjugate (FITC-BSA) as a vaccine model, formulations were selected with the construction of pseudo-ternary phase diagrams and a short-term stability study. The size of the emulsion droplets was furthered optimized with high-pressure homogenization. The optimized formulation was evaluated for its skin permeation efficiency. In vitro skin permeation studies were conducted with shaved BALB/c mice skin samples with a Franz diffusion cell system. Different drug concentrations were compared, and the effect of the nanoemulsion excipients on the permeation of the FITC-BSA was also studied.

Results: The optimum homogenization regime was determined to be five passes at 20?000?psi, with no evidence of protein degradation during processing. With these conditions, the particle diameter was 85.2?nm?±?15.5?nm with a polydispersity index of 0.186?±?0.026 and viscosity of 14.6 cP?±?1.2 cP. The optimized formulation proved stable for 1 year at 4?°C. In vitro skin diffusion studies show that the optimized formulation improves the permeation of FITC-BSA through skin with an enhancement ratio of 4.2 compared to a neat control solution. Finally, a comparison of the skin permeation of the nanoemulsion versus only the surfactant excipients resulted in a steady state flux of 23.44?μg/cm²/h for the nanoemulsion as opposed to 6.10?μg/cm²/h for the emulsifiers.

Conclusion: A novel nanoemulsion with optimized physical characteristics and superior skin permeation compared to control solution was manufactured. The formulation proposed in this study has the flexibility for the incorporation of a variety of active ingredients and warrants further development as a transcutaneous vaccine delivery vehicle.     

Binding affinity of fluorochromes and fluorescent proteins to Taxol™ crystals

The ability of Taxol (paclitaxel) to bind and stabilize microtubules is the basis for its use as an anti-mitotic drug as well as an additive for in vivo and in vitro studies of microtubules. The low solubility of Taxol in aqueous solutions, however, facilitates the formation of Taxol crystals that can be decorated with fluorescent tubulin. In cells treated with Taxol, these decorated Taxol crystals may be mistaken for self-assembled tubulin asters when observed with a fluorescent microscope. We confirmed via fluorescent and differential interference contrast microscopy that Taxol crystals can be decorated not only with fluorescent tubulin but also with other fluorescent proteins and fluorochromes without perturbing their morphology. We used theoretical calculations to further investigate Taxol-fluorescent agent interactions. Using computational docking studies we identified a new, potential Taxol binding site within the tubulin dimmer, allowing the interaction between crystalline Taxol and tubulin. Our calculations, however, show that fluorescent tubulin binding to Taxol crystals is more favorable via the fluorochromes covalently linked to the tubulin dimmers, rather than via the new Taxol-binding site, what is in accordance with our experimental data.     

In Vitro–In Vivo Characterization of Release Modifying Agents for Parenteral Sustained‐Release Ketorolac Formulation

One of the prerequisites for a parenteral preparation is that the excipients incorporated are biocompatible and biodegradable. In the present study hydrophilic and hydrophobic excipients were investigated for developing an intramuscular sustained‐release formulation of ketorolac. Kollidon® 17 PF, Peceol (glyceryl monooleate), and castor oil were chosen as the potential release‐retarding agents, each with a distinct mechanism of action. They were evaluated by in vitro drug‐release profiles and in vivo pharmacodynamic and pharmacokinetic study in mice. Cumulative drug release was determined for standard and test formulations in modified Franz diffusion cell. Pharmacodynamic parameter, T?=?70% response of peak analgesic response, was used to compare the performance of test formulations. Based on pharmacodynamic/pharmacokinetic correlation in the animal studies, Css_max and Css_min of 51.39 and 30.0 µg/mL, respectively, were determined and considered as performance markers for pharmacokinetic evaluation of test formulations. The study suggested that the sustained‐release capability of glyceryl monooleate was maximum followed by that of castor oil and Kollidon 17 PF, when compared to conventional ketorolac tromethamine formulation. It was inferred that water soluble excipient, though, showed release retarding property in vitro but could not maintain it in the in vivo environment. Glyceryl monooloeate‐based formulation produced the most favorable drug blood concentration vs. time profile.     

Formulation and in vivo evaluation of niosome-encapsulated daunorubicin hydrochloride

The central aim of this present study was to modify the reverse evaporation process, such that an enhanced entrapment, with increased storage stability and prolonged release, could be achieved, and to translate these advantages to increased therapeutic efficacy of daunorubicin hydrochloride on Dalton's ascitic lymphoma. Niosomes prepared exhibited entrapment efficiency 20% higher than theoretically possible by the reverse evaporation process. The niosomes were found to be very stable at a storage temperature of 4°C for a duration of three months. Even the drug leakage was restricted to just 10%. The in vivo studies suggested a prolonged release of 20 hr. Niosomal daunorubicin hydrochloride exhibited an enhanced anti-tumor efficacy when compared to free drug. The niosomal formulation was able to destroy the Dalton's ascitic lymphoma cells in the peritoneum within the third day of treatment, while free drug took around six days and the process was incomplete. The hematological studies also prove that the niosomal formulation was superior to free drug treatment. An enhanced mean survival time was achieved by the niosomal formulation that finally substantiates the overall efficacy of the niosomal formulation. This study suggests that the multilamellar vesicles obtained by the presently utilized reverse evaporation process resulted in vesicles that resisted the immediate lysis in the Kupffer cells, whereby a prolonged drug concentration was achieved which enhanced the cell lysis. But the major factor responsible for the quicker onset of action could be the increased permeability of the niosomes into the cell membrane and the cytoplasm of the Dalton's ascitic lymphoma cells.     

Formulation and In Vivo Evaluation of Niosome-Encapsulated Daunorubicin Hydrochloride

ABSTRACT

The central aim of this present study was to modify the reverse evaporation process, such that an enhanced entrapment, with increased storage stability and prolonged release, could be achieved, and to translate these advantages to increased therapeutic efficacy of daunorubicin hydrochloride on Dalton's ascitic lymphoma. Niosomes prepared exhibited entrapment efficiency 20% higher than theoretically possible by the reverse evaporation process. The niosomes were found to be very stable at a storage temperature of 4°C for a duration of three months. Even the drug leakage was restricted to just 10%. The in vivo studies suggested a prolonged release of 20 hr. Niosomal daunorubicin hydrochloride exhibited an enhanced anti-tumor efficacy when compared to free drug. The niosomal formulation was able to destroy the Dalton's ascitic lymphoma cells in the peritoneum within the third day of treatment, while free drug took around six days and the process was incomplete. The hematological studies also prove that the niosomal formulation was superior to free drug treatment. An enhanced mean survival time was achieved by the niosomal formulation that finally substantiates the overall efficacy of the niosomal formulation. This study suggests that the multilamellar vesicles obtained by the presently utilized reverse evaporation process resulted in vesicles that resisted the immediate lysis in the Kupffer cells, whereby a prolonged drug concentration was achieved which enhanced the cell lysis. But the major factor responsible for the quicker onset of action could be the increased permeability of the niosomes into the cell membrane and the cytoplasm of the Dalton's ascitic lymphoma cells.     

Antibody Conjugated PLGA Nanoparticles for Targeted Delivery of Paclitaxel Palmitate: Efficacy and Biofate in a Lung Cancer Mouse Model

Aberrant signaling of the epidermal growth factor receptor (EGFR) is common to a variety of human cancers and is also found to be over‐expressed in most cases of non‐small cell lung cancer. For the development of a molecularly targeted therapy, cetuximab‐conjugated nanoparticles (immunonanoparticles, INPs) are designed and loaded with the lipophilic paclitaxel palmitate (pcpl) prodrug. Oleyl cysteineamide (OCA) is synthesized whereby its amphiphilic nature enables interfacial anchoring and thiol surface functionalization of PLGA NPs, facilitating bioconjugation to cetuximab by thioether bonds. It is demonstrated that the in vitro targeting efficiency and improved cellular internalization and cytotoxicity of this targeted delivery system in lung cancer cells over‐expressing EGFR. A quantitative measure of the high binding affinity of INPs to EGFR is demonstrated using surface plasmon resonance. In vivo tolerability and enhanced efficacy of cetuximab pcpl INPs in a metastatic lung cancer model are reported. Its therapeutic efficacy in A549‐luc‐C8 lung tumors is shown using non‐invasive bioluminescent imaging. Intravenous administration of cetuximab pcpl INPs to mice results in significantly higher inhibition of tumor growth and increased survival rates as compared to the non‐targeted drug solution, drug‐loaded nanoparticles or blank INPs. Pharmacokinetics and organ biodistribution of the prodrug and parent drug are evaluated by LC‐MS/MS in lung tumor bearing mice. No enhanced total accumulation of nanoparticles or INPs is found at the tumor tissue. However, persistent pcpl levels with sustained conversion and release of paclitaxel are observed for the encapsulated prodrug possibly suggesting the formation of a drug reservoir. The overall results indicate the potential of this promising targeted platform for the improved treatment of lung cancer and other EGFR positive tumors.     

Cholesterol derivative-based liposomes for gemcitabine delivery: preparation,in vitro,and in vivo characterization

As an anti-tumor drug, gemcitabine (Gem) is commonly used for the treatment of non-small cell lung cancer and pancreatic cancer. However, there are several clinical drawbacks to using Gem, including its extremely short plasma half-life and side effects. To prolong its half-life and reduce its side effects, we synthesized a derivative of Gem using cholesterol (Chol). This derivative, called gemcitabine-cholesterol (Gem-Chol), was entrapped into liposomes by a thin-film dispersion method. The particle size of the Gem-Chol liposomes was 112.57?±?1.25?nm, the encapsulation efficiency was above 99%, and the drug loading efficiency was about 50%. In vitro studies revealed that the Gem-Chol liposomes showed delayed drug release and long-term stability at 4?°C for up to 2 months. In vivo studies also showed the superiority of the Gem-Chol liposomes, and compared with free Gem, the Gem-Chol liposomes had longer circulation time. Moreover, an anti-tumor study in H₂₂ and S180 tumor models showed that liposomal entrapment of Gem-Chol improved the anti-tumor effect of Gem. This study reports a potential formulation of Gem for clinical application.     

A Study on the Preparation and Anti-Tumor Efficacy of Bovine Serum Albumin Nanospheres Containing 5-Fluorouracil

ABSTRACT

The therapeutic profile of many anti-cancer drugs has been improved by their modified distribution through a colloidal carrier system. Hence, bovine serum albumin nanospheres containing 5-fluorouracil were prepared by pH-coacervation methods. To select the most suitable cryoprotector for the formulated nanosphere system, a study on the effect of cryoprotectors in the prevention of particle agglomeration was done. Using glucose and mannitol at various concentrations during freeze drying, glucose at a concentration of 5% was observed to be relatively more effective in the prevention of particle agglomeration than the other cryoprotectors. The carrier capacity was determined through the drug-to-albumin ratio. The particle size of all the drug-loaded batches was analyzed before and after freeze drying. The batch of nanospheres with uniform size distribution, and highest drug loading, was used for other subsequent studies. The effect of surfactant in drug loading was estimated through various concentrations of sodium lauryl sulfate, and it was observed that the surfactant has no influence on drug loading at the selected concentrations. The batch of nanospheres with highest drug loading was evaluated for its in-vitro release, and the drug release was found to be in a bi-phasic pattern. To evaluate the efficacy of 5-fluorouracil-loaded nanospheres against cancer cells, an in vitro cytotoxicity study was carried out using HEp-2 cell lines. The nanosphere-bound drug was observed to produce a better cytotoxic effect than the free drug. The anti-tumor efficacy of drug-loaded nanosphere was investigated in DLA tumor-induced mice models, and the percentage tumor inhibition was relatively higher in animals treated with nanosphere-bound drug than with free drug.     

A study on the preparation and anti-tumor efficacy of bovine serum albumin nanospheres containing 5-fluorouracil

The therapeutic profile of many anti-cancer drugs has been improved by their modified distribution through a colloidal carrier system. Hence, bovine serum albumin nanospheres containing 5-fluorouracil were prepared by pH-coacervation methods. To select the most suitable cryoprotector for the formulated nanosphere system, a study on the effect of cryoprotectors in the prevention of particle agglomeration was done. Using glucose and mannitol at various concentrations during freeze drying, glucose at a concentration of 5% was observed to be relatively more effective in the prevention of particle agglomeration than the other cryoprotectors. The carrier capacity was determined through the drug-to-albumin ratio. The particle size of all the drug-loaded batches was analyzed before and after freeze drying. The batch of nanospheres with uniform size distribution, and highest drug loading, was used for other subsequent studies. The effect of surfactant in drug loading was estimated through various concentrations of sodium lauryl sulfate, and it was observed that the surfactant has no influence on drug loading at the selected concentrations. The batch of nanospheres with highest drug loading was evaluated for its in-vitro release, and the drug release was found to be in a bi-phasic pattern. To evaluate the efficacy of 5-fluorouracil-loaded nanospheres against cancer cells, an in vitro cytotoxicity study was carried out using HEp-2 cell lines. The nanosphere-bound drug was observed to produce a better cytotoxic effect than the free drug. The anti-tumor efficacy of drug-loaded nanosphere was investigated in DLA tumor-induced mice models, and the percentage tumor inhibition was relatively higher in animals treated with nanosphere-bound drug than with free drug.