Design and Development of Ophthalmic Liposomes from the QbD Perspective.

Due to significant lachrymation, drug washing out, and poor adhesion to the lipophilic outer layer of the precorneal and cornea membrane, topical ophthalmic solution drops have poor ocular bioavailability. The rate of transcorneal absorption is impacted in the case of hydrophilic drug molecules as brimonidine tartrate, timolol maleate, cyclosporine, etc. Ophthalmic solution administered in many doses is less patient-compliant. The limitation of multiple-dose and its negative effects can be overcome by the development of delayed- release liposomes. Liposomes are regulatory-approved novel drug delivery systems. Its vesicular form aids in delaying medication release, and its lipidic makeup enables it to stick to the cornea's lipophilic layer. As a result, it will prevent precorneal clearing, extend corneal contact time, and provide sufficient transcorneal absorption. The aim of this review article is to portray the benefits of liposomes for ophthalmic drug delivery and its formulation development in the light of QbD. The review discusses the composition, preparatory methods and quality aspects of ophthalmic liposomes. It then accordingly reasonably proposes the quality target product profile, critical quality attributes, critical material attributes and critical process parameters, involved in liposome development for ophthalmic drug delivery. This review shall help formulation scientists to formulate ophthalmic liposomes of desirable quality.

Dual drug-loaded polymeric mixed micelles for ovarian cancer: Approach to enhanced therapeutic efficacy of albendazole and paclitaxel.

Chemotherapy resistance remains a significant challenge in treating ovarian cancer effectively. This study addresses this issue by utilizing a dual drug-loaded nanomicelle system comprising albendazole (ABZ) and paclitaxel (PTX), encapsulated in a novel carrier matrix of D-tocopheryl polyethylene glycol 1000 succinate vitamin E (TPGS), soluplus and folic acid. Our objective was to develop and optimize this nanoparticulate delivery system using solvent evaporation techniques to enhance the therapeutic efficacy against ovarian cancer. The formulation process involved pre-formulation, formulation, optimization, and comprehensive characterization of the micelles. Optimization was conducted through a 32 factorial design, focusing on the effects of polymer ratios on particle size, zeta potential, polydispersity index (PDI) and entrapment efficiency (%EE). The optimal formulation demonstrated improved dilution stability, as indicated by a critical micelle concentration (CMC) of 0.0015 mg/mL for the TPGS-folic acid conjugate (TPGS-FOL). Extensive characterization included differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), and Fourier-transform infrared spectroscopy (FTIR). The release profile exhibited an initial burst followed by sustained release over 90 h. The cytotoxic potential of the formulated micelles was superior to that of the drugs alone, as assessed by MTT assays on SKOV3 ovarian cell lines. Additionally, in vivo studies confirmed the presence of both drugs in plasma and tumour tissues, suggesting effective targeting and penetration. In conclusion, the developed TPGS-Fol-based nanomicelles for co-delivering ABZ and PTX show promising results in overcoming drug resistance, enhancing solubility, sustaining drug release, and improving therapeutic outcomes in ovarian cancer treatment.

Albendazole repurposing on VEGFR-2 for possible anticancer application: In-silico analysis.

Drug repurposing is the finding new activity of the existing drug. Recently, Albendazole's well-known antihelmintic has got the attention of an anticancer drug. Plausible evidence of the interaction of Albendazole with one of the types of tyrosine kinase protein receptor, vascular endothelial growth factor receptor-2 (VEGFR-2) is still not well understood. Inhibition of the VEGFR-2 receptor can prevent tumor growth. The current study investigated the interaction of Albendazole with VEGFR-2.It was found that the said interaction exhibited potent binding energy ΔG = -7.12 kcal/mol, inhibitory concentration (Ki) = 6.04 µM, and as positive control comparison with standard drug (42Q1170A) showed ΔG = -12.35 kcal/mol and Ki = 881 µM. The key residue Asp1046 was formed involved hydrogen bonding with Albendazole. The molecular dynamics simulation study revealed the stable trajectory of the VEGFR-2 receptor with Albendazole bound complex having significant high free energy of binding as calculated from Molecular Mechanics Generalized Born and Surface Area study ΔG = -42.07±2.4 kcal/mol. The binding energy is significantly high for greater stability of the complex. Principal component analysis of molecular docking trajectories exhibited ordered motion at higher modes, implying a high degree of VEGFR-2 and Albendazole complex stability as seen with the standard drug 42Q. Therefore, the current work suggests the role of Albendazole as a potent angiogenesis inhibitor as ascertained by its potential interaction with VEGFR-2. The findings of research will aid in the future development of Albendazole in anticancer therapy.

Comparative docking analysis of tyrosine kinase inhibitors with HER2 and HER4 receptors.

Tyrosine kinase receptors promote the growth and differentiation of normal breast and malignant human breast cancer cells, known as ERBB receptors. Various ERBB receptors are EGFR/ErbB1 and ErbB2/neu, which get over expressed in different solid tumors that activate upon binding of ligand to the extra cellular domain of these receptors. Of note, the epidermal growth factor receptor (EGFR) is a prime contributor to cancer through the involvement of four receptor tyrosine kinases (RTKs), namely, HER1, HER2, HER3, and HER4. Among them, HER2 and HER4 are majorly associated with breast cancer. Non-peptide quinazoline compounds homologous of the adenosine triphosphate (ATP) are competitively inhibited to RTKs to prevent cancer growth and metastasis. Various small drug molecule that targets the RTKs having the same scaffold, includes Lapatinib, Tivozanib, Erlotinib, Gefitinib, Crizotinib, and Ceritinib. The present study aims to investigate the comparative potential of structurally similar TKIs against HER2 and HER4 receptor receptors-silico molecular docking using FlexX software (LeadIT 2.3.2). Each docked complex's interaction profile was performed using BIOVIA Discovery Studio Visualizer 4.0. Molecular docking analysis was performed in order to get deeper insights into the interaction and binding pattern of the ligands with HER2 and HER4 receptors. The docking results revealed the Lapatinib compound acquired the relatively highest binding score of -32.36 kcal/mol and -35.76 kcal/mol with HER2 and HER4 proteins, respectively, concerning other compounds. Lapatinib is identified as a potential inhibitor for both the RTKs. Our study thus suggests the probable direction that could be further explored in inhibiting EGFR protein harboring breast cancer.

Optimization and Evaluation of Self-nanoemulsifying Drug Delivery System for Enhanced Bioavailability of Plumbagin.

Plumbagin, a potential bioactive lipophilic molecule, possesses limited solubility and low oral bioavailability. The purpose of the present study was to examine the potential of the self-nanoemulsifying drug delivery system for improving solubility and oral bioavailability of plumbagin. The self-nanoemulsifying drug delivery system was formulated from Capmul MCM (oil), Tween 20 (surfactant), and propylene glycol (cosurfactant). Central composite design was employed as statistical tool to optimize the formulation variables, X1 (oil) and X2 (surfactant: co-surfactant mixture ratio), of the self-nanoemulsifying drug delivery system. The responses studied were droplet size, self-emulsification time, % of drug release in 15 min, and equilibrium solubility. The optimized liquid self-nanoemulsifying drug delivery system was adsorbed on Neusilin US2 and characterized for flow properties, X-ray diffractometry, differential scanning calorimetry, in vitro dissolution, in vivo anti-inflammatory activity, and bioavailability study in Wistar rats, as well as ex vivo permeation study. The droplet size, polydispersity index, self-emulsification time, and equilibrium solubility of the optimized formulation were 58.500 ± 1.170 nm, 0.228 ± 0.012, 17.660 ± 1.520 s, and 34.180 ± 1.380 mg/mL, respectively. Its zeta potential, transmittance value, and cloud point were - 28.200 ± 1.200 mV, 99.200% ± 0.600, and 90 °C, respectively. Drug release was found to be 93.320% ± 1.090. In vivo anti-inflammatory study confirmed more enhanced activity from the self-nanoemulsifying drug delivery system than with pure plumbagin. Pharmacokinetic study in rats revealed that solid self-nanoemulsifying drug delivery system had 4.49-fold higher bioavailability than pure plumbagin. Ex vivo permeation study demonstrated 1.75-fold increased intestinal permeability of the self-nanoemulsifying drug delivery system than pure plumbagin. The developed self-nanoemulsifying drug delivery system is a useful solid platform for improving solubility and oral bioavailability of plumbagin.

Development of fisetin-loaded folate functionalized pluronic micelles for breast cancer targeting.

The natural flavonoid fisetin (FS) has shown anticancer properties but its in-vivo administration remains challenging due to its poor aqueous solubility. The aim of the study was to develop FS loaded pluronic127 (PF)-folic acid (FA) conjugated micelles (FS-PF-FA) by the way of increasing solubility, bioavailability and active targetability of FS shall increase its therapeutic efficacy. FA-conjugated PF was prepared by carbodiimide crosslinker chemistry. FS-PF-FA micelles were prepared by thin-film hydration method and evaluated in comparison with free FS and FS loaded PF micelles (FS-PF). The smooth surfaces with spherical in shape of FS-PF-PF micelles displayed smaller in size (103.2 ± 6.1 nm), good encapsulation efficiency (82.50 ± 1.78%), zeta potential (-26.7 ± 0.44 mV) and sustained FS release. Bioavailability of FS from FS-PF-PF micelles was increased by 6-fold with long circulation time, slower plasma elimination and no sign of tissue toxicity as compared to free FS. Further, the FS-PF-FA micelles demonstrated active targeting effect on folate overexpressed human breast cancer MCF-7 cells. The concentration of the drug needed for growth inhibition of 50% of cells in a designed time period (GI50) was 14.3 ± 1.2 µg/ml for FS while it was greatly decreased to 9.8 ± 0.78 µg/ml, i.e. a 31.46% decrease for the FS-PF. Furthermore, the GI50 value for FS-PF-FA was 4.9 ± 0.4 µg/ml, i.e. a 65.737% decrease compared to FS and 50% decrease compare to FS-PF. The results indicate that the FS-PF-FA micelles have the potential to be applied for targeting anticancer drug delivery.

Enhanced hepatoprotective activity of andrographolide complexed with a biomaterial.

CONTEXT: Humic acid (HA), a natural organic matter is recently being investigated for pharmaceutical purposes. Andrographolide (AGP), a potent hepatoprotective, possesses low aqueous solubility which results in a low bioavailability after oral administration, inappropriate tissue localization and consequently poor therapeutic application. OBJECTIVE: The present study investigates the complexation of AGP with HA to increase its solubility and hepatoprotective efficacy. MATERIALS AND METHODS: Complexes prepared by solvent evaporation in various weight ratios were characterized using differential scanning calorimetry, Fourier Transform InfraRed spectroscopy, X-ray diffraction, and scanning electron microscopy. RESULTS AND DISCUSSION: The complexed AGP demonstrated improved solubility, dissolution, and permeation across rat intestine. It also displayed better hepatoprotection against carbontetrachloride-induced liver toxicity than the free drug in rats. CONCLUSION: Complexation with HA is a valuable technique to improve solubility and bioavailability of pharmaceuticals.

Investigation of ethyl cellulose microsponge gel for topical delivery of eberconazole nitrate for fungal therapy.

BACKGROUND: The aim of the study was to investigate ethyl cellulose microsponges as topical carriers for the controlled release and cutaneous drug deposition of eberconazole nitrate (EB). MATERIALS & METHOD: EB microsponges were prepared using the quasiemulsion solvent diffusion method. The effect of formulation variables (drug:polymer ratio, internal phase volume and amount of emulsifier) and process variables (stirring time and stirring speed) on the physical characteristics of microsponges were investigated. The optimized microsponges were dispersed into a hydrogel and evaluated. RESULTS & DISCUSSION: Spherical and porous EB microsponge particles were obtained. The optimized microsponges possessed particle size, drug content and entrapment efficiency of 24.5 µm, 43.31% and 91.44%, respectively. Microsponge-loaded gels demonstrated controlled release, nonirritancy to rat skin and antifungal activity. An in vivo skin deposition study demonstrated fourfold higher retention in the stratum corneum layer as compared with commercial cream. CONCLUSION: Developed ethyl cellulose microsponges could be potential pharmaceutical topical carriers of EB in antifungal therapy.

Application of liquisolid technology for enhancing solubility and dissolution of rosuvastatin.

PURPOSE: Rosuvastatin is a poorly water soluble drug and the rate of its oral absorption is often controlled by the dissolution rate in the gastrointestinal tract. Hence it is necessary to increase the solubility of the Rosuvastatin. METHODS: Several liquisolid tablets formulations containing various drug concentrations in liquid medication (ranging from 15% to 25% w/w) were prepared. The ratio of Avicel PH 102 (carrier) to Aerosil 200 (coating powder material) was kept 10, 20, 30. The prepared liquisolid systems were evaluated for their flow properties and possible drug-excipient interactions by Infrared spectra (IR) analysis, differential scanning calorimetry (DSC) and X- ray powder diffraction (XRPD). RESULTS: The liquisolid system showed acceptable flow properties. The IR and DSC studies demonstrated that there is no significant interaction between the drug and excipients. The XRPD analysis confirmed formation of a solid solution inside the compact matrix. The tabletting properties of the liquisolid compacts were within the acceptable limits. Liquisolid compacts demonstrated significantly higher drug release rates than those of conventional and marketed tablet due to increasing wetting properties and surface area of the drug. CONCLUSION: This study shows that liquisolid technique is a promising alternative for improvement of the dissolution rate of water insoluble drug.

Fisetin-loaded nanocochleates: formulation, characterisation, in vitro anticancer testing, bioavailability and biodistribution study.

BACKGROUND: The natural flavonoid fisetin has shown anticancer properties but its in vivo administration remains challenging due its poor aqueous solubility and extensive in vivo metabolism. This juncture demands an effective, controlled release and safe formulation of fisetin would be a significant advance for the treatment of cancer. OBJECTIVES: Nanocochleates are unique lipid-based supramolecular assemblies composed of a negatively charged phospholipid and a divalent cation. The aim was to develop and evaluate fisetin-loaded nanocochleates to improve its therapeutic efficacy. Using the trapping method, fisetin-loaded dimyristoylphosphatidylcholine liposomal vesicles were converted into nanocochleates by the action of Ca(2+) ions. These nanocochleates were further evaluated for physicochemical, in vitro anticancer and haemolysis, pharmacokinetics and tissue distribution study in mice. RESULTS: Stable rolled-up layers as well as elongated structure of nanocochleates possessing particle size and encapsulation efficiency (EE) of 275 + 4 nm and 84.31 ± 2.52%, respectively were obtained. Nanocochleates demonstrated safety and a sustained release of fisetin at physiological pH. A 1.3-fold improvement in vitro anticancer towards human breast cancer MCF-7 cells was observed. Pharmacokinetics studies in mice revealed that nanocochleates injected intraperitonially showed a 141-fold higher relative bioavailability. Moreover, a low tissue distribution was observed. CONCLUSION: Developed nanocochleates markedly improved anticancer efficacy, bioavailability and safety of fisetin. The nanocochleates technology would facilitate the administration of this flavonoid in the clinical setting. AREAS COVERED: In this research article, we focused on lipid-based supramolecular assembly 'nanocochleates' composed of negatively charged phospholipids and divalent cation as drug carrier for systemic delivery system and discussed their formulations, optimisation, characterization, in vitro and in vivo performance.

Development of plumbagin-loaded phospholipid-Tween® 80 mixed micelles: formulation, optimization, effect on breast cancer cells and human blood/serum compatibility testing.

BACKGROUND: Phospholipid and Tween(®) 80 mixed micelles were investigated as injectable nanocarriers for the natural anticancer compound, plumbagin (PBG), with the aim to improve anticancer efficiency. PBG-loaded mixed micelles were fabricated by self-assembly; composition being optimized using 3(2) factorial design. RESULTS & DISCUSSION: Optimized mixed micelles were spherical and 46 nm in size. Zeta potential, drug loading and encapsulation efficiency were 5.04 mV, 91.21 and 98.38% respectively. Micelles demonstrated sustained release of PBG. Micelles caused a 2.1-fold enhancement in vitro antitumor activity of PBG towards MCF-7 cells. Micelles proved safe for intravenous injection as PBG was stable at high pH; micelle size and encapsulation efficiency were retained upon dilution. CONCLUSION: Developed mixed micelles proved potential nanocarriers for PBG in cancer chemotherapy.

A study on ethosomes as mode for transdermal delivery of an antidiabetic drug.

CONTEXT: A transdermal delivery system is warranted for repaglinide (RPG) which possesses half-life of 1 h and oral bioavailability of 56%. Ethosomes are useful tools for transdermal drug delivery. OBJECTIVES: To prepare and evaluate ethosomes as mode for transdermal delivery of RPG. MATERIAL AND METHODS: Ethosomes loaded with RPG were prepared from dipalmitoyl phosphatidylcholine and ethanol by the cold method. They were characterized using Fourier transform infrared spectroscopy and differential scanning calorimetry. They were evaluated for vesicle size, entrapment efficiency and ex-vivo skin permeation. Ethosomal composition was optimized using the 3(2) factorial design. Gel containing optimzsed ethosomes was studied for antidiabetic activity in rats. RESULT: RPG ethosomes possessing the size of 0.171-1.727 µm and entrapment efficiency of 75-92% were obtained. They demonstrated a significantly higher permeation (64-97% of the administered dose) across excised rat skin when compared to free drug and its hydro alcoholic solution. In-vivo, RPG ethosomal system caused sustained antidiabetic effect. DISCUSSION: The lipid and ethanol concentration affected the physicochemical attributes and performance of ethosomes. The flexible ethosomes permeated the stratum corneum and improvized the availability of RPG for antidiabetic action. They prolonged the antidiabetic effect of RPG over a significantly longer period of time in comparison with the equivalent oral dose. CONCLUSION: Ethosomal system can successfully deliver RPG transdermally; sustain its effect and thus reduce its dosing frequency. Ethosomes are useful for enhancing the efficacy of RPG in the treatment of diabetes.

Novel solvent-free gelucire extract of Plumbago zeylanica using non-everted rat intestinal sac method for improved therapeutic efficacy of plumbagin.

INTRODUCTION: Various shortcomings of the available methods of extraction of plumbagin from Plumbago zeylanica using non-edible organic solvents coupled with the poor aqueous solubility and low bioavailability called for extracting plumbagin in a water soluble form via a single step technique using hydrophilic lipid Gelucire 44/14. METHODS: Gelucire extract of P. zeylanica (GPZ) was prepared and evaluated for extraction efficiency, High-performance thin layer chromatography (HPTLC) and thermal analysis. In vitro intestinal absorption and bioavailability of plumbagin from GPZ in comparison with that of aqueous (APZ), ethanolic extract (EPZ) and standard plumbagin studied using non-everted rat intestinal sac model. RESULTS: The GPZ showed significantly higher extraction efficiency (3.24±0.12% w/w) compared to ethanolic (EPZ) and aqueous (APZ) extraction, 2.48±0.16% w/w and 0.07±0.02% w/w respectively. GPZ displayed significantly higher Q(30min) (cumulative percentage absorption of plumbagin in 30 min) and lower t(40%) (time required for 40% w/w drug absorption). The flux and apparent permeability coefficient in duodenum and ileum were 2, 3 and 6 fold higher than EPZ, standard plumbagin and APZ respectively. DISCUSSION: Improved therapeutic efficacy of plumbagin may be due to the micellar solubilization and consequent enhanced partitioning of plumbagin through intestinal by Gelucire which was reflected in the in vivo anti-inflammatory study conducted in rats. CONCLUSION: Thus extraction using Gelucire can be proclaimed as an efficient, economic and solvent-free technique for extraction of plumbagin and can be utilized for various clinically important water insoluble phytoconstituents in order to improve their biopharmaceutical properties.

Optimization, characterisation and pharmacokinetic studies of mucoadhesive oral multiple unit systems of ornidazole.

The objective of the present study was to investigate the applicability of matrix type mucoadhesive oral multiple unit systems (MUS) for sustaining the release of ornidazole in the gastrointestinal tract (GIT). The MUS were prepared by ionotropic gelation method using chitosan and hydroxypropyl methyl cellulose K4M (HPMC K4M) according to 3(2) factorial designs and were evaluated in vitro and in vivo. The particle size length ranged from 0.78 to 1.30 mm and breadth from 0.76 to 1.30 mm, respectively. The entrapment efficiency was in range of 80 to 96%. The rapid wash-off test was observed faster at intestinal pH 6.8 as compared to acidic pH 1.2. The fluoroscopic study revealed the retention of MUS in GIT for more than 5 hours. The pharmacokinetic parameters C(max), T(max), mean residence time (MRT) and area under curve (AUC) of developed MUS were found to be improved significantly (p<0.05) when compared with marketed immediate release tablets each containing 500 mg of drug. This study demonstrates that the MUS could be a good alternative to immediate release tablets to deliver ornidazole and expected to be less irritant to gastric and intestinal mucosa.

Studies on nonionic surfactant bilayer vesicles of ciclopirox olamine.

CONTEXT: Niosomal delivery can prove an alternative to improve the poor skin penetration and residence of the topical antifungal drugs that account for the long treatment regimes in cutaneous mycosis. OBJECTIVE: To investigate niosomes as carriers for dermal delivery of ciclopirox olamine (CPO), a broad spectrum antifungal drug. MATERIALS AND METHODS: Niosomes were prepared by ethanol injection method using Span 60, cholesterol, diacetyl phosphate according to 3(2) factorial design and evaluated for physicochemical parameters, in vitro and ex vivo deposition in skin and stability study. RESULTS: Unilamellar CPO niosomes of size 170-280 nm, entrapment efficiency 38-68%, and sufficient electrokinetic stability were obtained. Percent drug deposition in artificial membrane varied from 12.75 to 92.74. Deposition of CPO into rat skin from niosomal dispersion and its gel was significantly higher than that of plain CPO solution and its marketed product. Obtained niosomes possessed sufficient stability on storage. DISCUSSION: Increasing amounts of Span 60 and cholesterol increase the vesicle size probably because of entrapment of CPO-ionized molecules in the aqueous compartment and interaction of its unionized counterpart with the bilayer constituents leading to increase in bilayer thickness. Consequently, the percent entrapment efficiency also increased. However, increasing Span 60 levels decreased the in vitro percent drug deposition. This might be attributed to the larger size of vesicles produced by high amounts of surfactant that showed poor deposition. The optimized batch possessed sufficient stability. CONCLUSIONS: The results of this investigation suggest that niosomes are promising tools for cutaneous retention of CPO.