Uptake of phenothiazines by the harvested chylomicrons ex vivo model: Influence of self-nanoemulsifying formulation design

Development of polymer-encapsulated microparticles of a lipophilic API-IL and its lipid based formulations for enhanced solubilisation

Active Pharmaceutical Ingredient-Ionic liquids (API-ILs) have the potential to improve the bioavailability of BCS Class IV Drugs. However, the problematic physical handling properties of room temperature API-ILs have impaired clinical and commercial exploitation to date. Lipid-based formulations (LBFs) are used to improve the absorption of drugs with limited bioavailability. Nonetheless, LBFs face limitations such as low drug loading capacity and sub-par physical stability. A platform for transforming API-ILs into solid forms at high loadings via spray encapsulation with polymers has been developed and previously demonstrated for hydrophilic API-ILs. The current work demonstrates that this platform technology can be applied to a lipophilic API-IL of the BCS Class IV API, chlorpromazine, and to multi-component solutions comprising API-IL and a LBF. Furthermore, solidification of a type IIIB, liquid LBF was achieved via spray encapsulation with cellulose- and methacrylate- based polymers for the first time. The spray-encapsulated formulations had excellent physical handling properties, and successfully eluted the API-IL in aqueous media. The chlorpromazine release profiles from the API-IL, the API-IL containing LBF, and the solidified formulations, were evaluated in vitro using phosphate buffer (pH 6.8) and fasted state simulated intestinal fluid (FaSSIF). Spray-encapsulated formulations exhibited improved release profiles compared to the liquid formulations. Overall, these findings indicate that phase-separated, polymeric, solid formulations of liquid API forms represent a promising platform technology for developing oral solid dosage forms of poorly bioavailable drugs.

Novel griseofulvin zinc nanohybrid emulsion for intensifying the antimicrobial control of dermatophytes and some opportunistic pathogens

Dermatophytosis is a critical sort of skin infection caused by dermatophytes. The long-term treatment of such skin infections may be improved through the application of nanotechnology. This study aimed to prepare griseofulvin zinc Nanohybrid emulsion (GF-Zn-NHE) to improve griseofulvin activity against dermatophytes and some opportunistic pathogenic yeasts and bacteria. The GF-Zn-NHE is prepared by ultra-homogenization ultra-sonication strategies and validated by UV-visible spectroscopy analysis that confirms presences of griseofulvin and Zn-NPs peaks at 265 and 360 nm, respectively. The GF-Zn-NHE has mean distribution size 50 nm and zeta potential in the range from -40 to -36 mV with no significant changes in size distribution and particle size within 120 day ageing. Fourier transform infrared spectroscopy spectrum confirmed the presence of griseofulvin and Zn-NPs stretching vibration peaks. Gamma ray has a negative influence on GF-Zn-NE production and stability. GF-Zn-NHE drug release 95% up to 24 h and 98% up to 72 h of GF was observed and Zinc 90% up to 24 h and 95% up to 72 h, respectively. High antimicrobial activity was observed with GF-Zn-NHE against dermatophytic pathogens in compare with GF, GF-NE, zinc nitrate and ketoconazole with inhibition zone ranged from 14 to 36 mm. The results have shown that the MIC value for Cryptococcus neoformans, Prophyromonas gingivalis and Pseudomonas aeruginosa is 0.125 mg ml -1 and for Trichophyton rubrum, L. bulgaricus and Escherichia coli value is 0.25 mg ml -1 and for Candida albicans, Malassezia furfur and Enterococcus faecalis is 0.5 mg ml -1 and finally 1 mg ml -1 for Streptococcus mutans. TEM of treated Cryptococcus neoformans cells with GF-Zn-NHE displayed essentially modified morphology, degradation, damage of organelles, vacuoles and other structures.

Regorafenib loaded self-assembled lipid-based nanocarrier for colorectal cancer treatment via lymphatic absorption

Oral chemotherapy can improve the life quality of patients; however, the therapeutic effects are limited by low bioavailability and rapid in vivo elimination of anticancer drugs. Here, we developed a regorafenib (REG)-loaded self-assembled lipid-based nanocarrier (SALN) to improve oral absorption and anti-colorectal cancer efficacy of REG through lymphatic absorption. SALN was prepared with lipid-based excipients to utilize lipid transport in the enterocytes and enhance lymphatic absorption of the drug in the gastrointestinal tract. The particle size of SALN was 106 ± 10 nm. SALNs were internalized by the intestinal epithelium via the clathrin-mediated endocytosis, and then transported across the epithelium via the chylomicron secretion pathway, resulting in a 3.76-fold increase in drug epithelial permeability (P_app) compared to the solid dispersion (SD). After oral administration to rats, SALNs were transported by the endoplasmic reticulum, Golgi apparatus, and secretory vesicles of enterocytes and were found in the lamina propria of intestinal villi, abdominal mesenteric lymph, and plasma. The oral bioavailability of SALN was 65.9-fold and 1.70-fold greater than that of the coarse powder suspension and SD, respectively, and was highly dependent on the lymphatic route of absorption. Notably, SALN prolonged the elimination half-life of the drug (9.34 ± 2.51 h) compared to the solid dispersion (3.51 ± 0.46 h), increased the biodistribution of REG in the tumor and gastrointestinal (GI) tract, decreased biodistribution in the liver, and showed better therapeutic efficacy than the solid dispersion in colorectal tumor-bearing mice. These results demonstrated that SALN is promising for the treatment of colorectal cancer via lymphatic transport and has potential for clinical translation.

Self-Nano-Emulsifying Drug-Delivery Systems: From the Development to the Current Applications and Challenges in Oral Drug Delivery

Approximately one third of newly discovered drug molecules show insufficient water solubility and therefore low oral bio-availability. Self-nano-emulsifying drug-delivery systems (SNEDDSs) are one of the emerging strategies developed to tackle the issues associated with their oral delivery. SNEDDSs are composed of an oil phase, surfactant, and cosurfactant or cosolvent. SNEDDSs characteristics, their ability to dissolve a drug, and in vivo considerations are determinant factors in the choice of SNEDDSs excipients. A SNEDDS formulation can be optimized through phase diagram approach or statistical design of experiments. The characterization of SNEDDSs includes multiple orthogonal methods required to fully control SNEDDS manufacture, stability, and biological fate. Encapsulating a drug in SNEDDSs can lead to increased solubilization, stability in the gastro-intestinal tract, and absorption, resulting in enhanced bio-availability. The transformation of liquid SNEDDSs into solid dosage forms has been shown to increase the stability and patient compliance. Supersaturated, mucus-permeating, and targeted SNEDDSs can be developed to increase efficacy and patient compliance. Self-emulsification approach has been successful in oral drug delivery. The present review gives an insight of SNEDDSs for the oral administration of both lipophilic and hydrophilic compounds from the experimental bench to marketed products.

Development of a Self-Emulsifying Drug Delivery System for Optimized Topical Delivery of Clofazimine

A quality-by-design and characterization approach was followed to ensure development of self-emulsifying drug delivery systems (SEDDSs) destined for topical delivery of the highly lipophilic clofazimine. Solubility and water-titration experiments identified spontaneous emulsification capacity of different excipient combinations and clofazimine. After identifying self-emulsification regions, check-point formulations were selected within the self-emulsification region by considering characteristics required to achieve optimized topical drug delivery. Check-point formulations, able to withstand phase separation after 24 h at an ambient temperature, were subjected to characterization studies. Experiments involved droplet size evaluation; size distribution; zeta-potential; self-emulsification time and efficacy; viscosity and pH measurement; cloud point assessment; and thermodynamic stability studies. SEDDSs with favorable properties, i.e., topical drug delivery, were subjected to dermal diffusion studies. Successful in vitro topical clofazimine delivery was observed. Olive oil facilitated the highest topical delivery of clofazimine probably due to increased oleic acid levels that enhanced stratum corneum lipid disruption, followed by improved dermal clofazimine delivery. Finally, isothermal microcalometric experiments studied the compatibility of excipients. Potential interactions were depicted between argan oil and clofazimine as well as between Span®60 and argan-, macadamia- and olive oil, respectively. However, despite some mundane incompatibilities, successful development of topical SEDDSs achieved enhanced topical clofazimine delivery.

Distribution of Psychotropic Drugs Into Lipoproteins

AIM

The aim of this pilot study was to investigate whether psychotropic drugs frequently analyzed in a routine therapeutic drug monitoring laboratory bind to low-density lipoproteins/very-low-density lipoproteins (LDL/VLDL) in human serum.

METHODS

Drug concentrations in 20 serum sample pools containing one psychotropic drug each, and in the LDL/VLDL fractions extracted from the same samples, were measured by triple quadrupole liquid chromatography tandem mass spectrometry. The membrane permeability of the drugs was measured using a Parallel Artificial Membrane Permeability Assay.

RESULTS

Of the 20 antidepressants, antipsychotics, and antiepileptics examined, 7 drugs were detected in both the pooled serum samples and in the LDL/VLDL fraction. Binding of drugs to LDL/VLDL significantly correlated with high octanol: water partition coefficient (logP), high degree of protein binding, and a low polar surface area. The drugs found in LDL/VLDL, with the exception of aripiprazole, were also characterized by high or intermediate membrane permeability.

CONCLUSIONS

The present results indicate that psychotropic drugs with certain characteristics bind to LDL/VLDL in blood. This further implies that lipoproteins could play an important role in drug transport.

Self-Nanoemulsifying Drug Delivery System (SNEDDS) for Improved Oral Bioavailability of Chlorpromazine: In Vitro and In Vivo Evaluation

Background and Objectives: Lipid-based self-nanoemulsifying drug delivery systems (SNEDDS) have resurged the eminence of nanoemulsions by modest adjustments and offer many valuable opportunities in drug delivery. Chlorpromazine, an antipsychotic agent with poor aqueous solubility-with extensive first-pass metabolism-can be a suitable candidate for the development of SNEDDS. The current study was designed to develop triglyceride-based SNEDDS of chlorpromazine to achieve improved solubility, stability, and oral bioavailability. Materials and Methods: Fifteen SNEDDS formulations of each short, medium, and long chain, triglycerides were synthesized and characterized to achieve optimized formulation. The optimized formulation was characterized for several in vitro and in vivo parameters. Results: Particle size, zeta potential, and drug loading of the optimized SNEDDS (LCT14) were found to be 178 ± 16, -21.4, and 85.5%, respectively. Long chain triglyceride (LCT14) showed a 1.5-fold increased elimination half-life (p < 0.01), up to 6-fold increased oral bioavailability, and 1.7-fold decreased plasma clearance rate (p < 0.01) compared to a drug suspension. Conclusion: The findings suggest that SNEDDS based on long-chain triglycerides (LCT14) formulations seem to be a promising alternative for improving the oral bioavailability of chlorpromazine.

Preparation and characterization of self nano-emulsifying drug delivery system (SNEDDS) for oral delivery of heparin using hydrophobic complexation by cationic polymer of β-cyclodextrin

OBJECTIVE

The aim of this study was the preparation of a self nano-emulsifying drug delivery system (SNEDDS) for oral delivery of heparin.

SIGNIFICANCE

Preparation of hydrophobic complexes between heparin as the hydrophilic macromolecule and cationic polymer of β-cyclodextrin (CPβCD) was considered for preparation of orally administered SNEDDS in which the drug incorporated in internal oil phase of O/W nano-droplets.

METHODS

Hydrophobic complexes of heparin-CPβCD were prepared by electrostatic interaction. The lipophilic feature of complexes was characterized by determining their partition co-efficients. SNEDDS prototypes were prepared by mixing liquid paraffin, Tween 80, propylene glycol and ethanol, diluted 1:100 in an aqueous medium. Central composite response surface methodology was applied for statistical optimization. Independent variables were the amount of liquid paraffin and the amount of Tween 80, while responses were size and poly dispersity index (PdI). Optimized SNEDDS were studied morphologically using transmission electron microscopy (TEM). In vitro release of heparin was studied in the simulated gastric and simulated intestinal media.

RESULTS

The data revealed that in molar ratio 1:3 (heparin:CPβCD), the n-octanol recovery was maximized and reached 67.6 ± 11.86%. Size, PdI, zeta potential, EE% in gastric medium and EE% in intestinal medium for optimized nano-droplets were reported as 307 ± 30.51 nm, 0.236 ± 0.02, +2.1 ± 0.66 mV, 90.2 ± 0.04 and 96.1 ± 0.73%, respectively. Microscopic images revealed spherical nano-droplets. The obtained data revealed no burst release of heparin from nano-droplets.

CONCLUSIONS

The obtained results indicate that SNEDDS could be regarded as a good candidate for oral delivery of heparin as the hydrophilic macromolecule.

Preparation and In Vitro/In Vivo Evaluation of Puerarin Solid Self-Microemulsifying Drug Delivery System by Spherical Crystallization Technique

The aim of this work was to establish a method for preparing stable and controllable solid self-microemulsifying drug delivery system (S-SMEDDS) by spherical crystallization technique, which was explored for promoting the dissolution, oral bioavailability, and process efficiency. Solubility test, preparation of liquid self-microemulsifying drug delivery system (L-SMEDDS), and the obtained ternary phase diagrams test have been performed to screen and optimize the composition of LSMEDDS. The optimized formulation was used to prepare puerarin solid self-microemulsifying drug delivery system (Pue-SSMEDDS) by spherical crystallization technique. Droplet size and morphological analysis of the optimal Pue-SSMEDDS were determined to evaluate the final formulation. And the Pue-SSMEDDS was also assessed by flowability study, angle of repose, Carr's index, and flow velocity. Furthermore, the vitro dissolution and pharmacokinetic profile in vivo were analyzed. The study in vitro showed the Pue-SSMEDDS could disperse in the dispersion medium within 60 s and was spherical with the particle size of 19.66 nm and zeta potential of -28.3 mV. It could keep stable at low temperature and seal condition for 3 months. In vivo pharmacokinetic experiments of rats, the mean plasma concentration of self-microemulsion group was much higher than that of conventional tablets and could play a long-lasting efficacy, while there was no significant difference between the LSMEDDS and S-SMEDDS. The results suggested the potential of S-SMEDDS could improve the oral bioavailability of poorly water-soluble drug, such as puerarin.

Lipid-based nanocarriers for the oral administration of biopharmaceutics

Biopharmaceutics have been recognized as the drugs of choice for the treatment of several diseases, mainly due to their high selectivity and potent action. Nonetheless, their oral administration is a rather challenging problem, since their bioavailability is significantly hindered by various physiological barriers along the GI tract, including their acid-induced hydrolysis in the stomach, their enzymatic degradation throughout the GI tract and their poor mucosa permeability. Lipid-based nanocarriers represent a viable means for enhancing the oral bioavailability of biomolecules while diminishing toxicity-related issues. The present review describes the main physiological barriers limiting the oral bioavailability of macromolecules and highlights recent advances in the field of lipid-based carriers as well as the respective lipid intestinal absorption mechanisms.

Development, in vitro and in vivo evaluation of a self-emulsifying drug delivery system (SEDDS) for oral enoxaparin administration

AIM

The aim of this study was to develop SEDDS for oral enoxaparin administration and evaluate it in vitro and in vivo.

METHODS

The emulsifying properties of SEDDS composed of long chain lipids (LC-SEDDS), medium chain lipids (MC-SEDDS), short chain lipids (SC-SEDDS) and no lipids (NL-SEDDS) were evaluated. Thereafter, enoxaparin was incorporated via hydrophobic ion pairing in the chosen SEDDS, which were evaluated regarding their mucus permeating properties, stability towards pancreatic lipase, drug release profile and cytotoxicity. Finally, in vivo performance of SEDDS was evaluated.

RESULTS

The average droplet size of chosen LC-SEDDS, MC-SEDDS and NL-SEDDS ranged between 30 and 40nm. MC-SEEDS containing 30% Captex 8000, 30% Capmul MCM, 30% Cremophor EL and 10% propylene glycol and NL-SEDDS containing 31.5% Labrafil 1944, 22.5% Capmul PG-8, 9% propylene glycol, 27% Cremophor EL and 10% DMSO exhibited 2-fold higher mucus diffusion than LC-SEDDS and were therefore chosen for further studies. The enoxaparin-dodecylamine complex (ENOX/DOA) was incorporated in a payload of 2% (w/w) into MC-SEDDS and NL-SEDDS. After 90min 97% of MC-SEDDS and 5% of NL-SEDDS were degraded by pancreatic lipase. Both MC-SEDDS and NL-SEDDS showed sustained in vitro enoxaparin release. Furthermore, orally administrated MC-SEDDS and NL-SEDDS yielded an absolute enoxaparin bioavailability of 2.02% and 2.25%, respectively.

CONCLUSION

According to the abovementioned findings, SEDDS could be considered as a potential oral LMWH delivery system.

A Self-microemulsifying Drug Delivery System (SMEDDS) for a Novel Medicative Compound Against Depression: a Preparation and Bioavailability Study in Rats

AJS is the code name of an untitled novel medicative compound synthesized by the Tasly Holding Group Company (Tianjin, China) based on the structure of cinnamamide, which is one of the Biopharmaceutics Classification System (BCS) class II drugs. The drug has better antidepressant effect, achieved by acting on the 5-hydroxytryptamine receptor. However, the therapeutic effects of the drug are compromised due to its poor water solubility and lower bioavailability. Herein, a self-microemulsifying drug delivery system (SMEDDS) was developed to improve its solubility and oral bioavailability. AJS-SMEDDS formulation was optimized in terms of drug solubility in the excipients, droplet size, stability, and drug precipitation using a pseudo-ternary diagram. The pharmacokinetic study was performed in rats, and the drug concentration in plasma samples was assayed using the high-performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-MS/MS) method. The optimized formulation for SMEDDS has a composition of castor oil 24.5%, Labrasol 28.6%, Cremphor EL 40.8%, and Transcutol HP 2.7% (co-surfactant). No drug precipitation or phase separation was observed from the optimized formulation after 3 months of storing at 25°C. The droplet size of microemulsion formed by the optimized formulation was 26.08 ± 1.68 nm, and the zeta potential was -2.76 mV. The oral bioavailability of AJS-SMEDDS was increased by 3.4- and 35.9-fold, respectively, compared with the solid dispersion and cyclodextrin inclusion; meanwhile, the C max of AJS-SMEDDS was about 2- and 40-fold as great as the two controls, respectively. In summary, the present SMEDDS enhanced oral bioavailability of AJS and was a promising strategy to orally deliver the drug.

PLGA biodegradable nanoparticles containing perphenazine or chlorpromazine hydrochloride: effect of formulation and release

In our study, poly(dl-lactide-co-glycolide) (PLGA) nanoparticles loaded with perphenazine (PPH) and chlorpromazine hydrochloride (CPZ-HCl) were formulated by emulsion solvent evaporation technique. The effect of various processing variables, including PLGA concentration, theoretical drug loading, poly(vinyl alcohol) (PVA) concentration and the power of sonication were assessed systematically to obtain higher encapsulation efficiency and to minimize the nanoparticles size. By the optimization formulation process, the nanoparticles were obtained in submicron size from 325.5 ± 32.4 to 374.3 ± 10.1 nm for nanoparticles loaded with PPH and CPZ-HCl, respectively. Nanoparticles observed by scanning electron microscopy (SEM) presented smooth surface and spherical shape. The encapsulation efficiency of nanoparticles loaded with PPH and CPZ-HCl were 83.9% and 71.0%, respectively. The drug loading were 51.1% and 39.4% for PPH and CPZ-HCl, respectively. Lyophilized nanoparticles with different PLGA concentration 0.8%, 1.3% and 1.6% (w/v) in formulation process were evaluated for in vitro release in phosphate buffered saline (pH = 7.4) by using dialysis bags. The release profile for both drugs have shown that the rate of PPH and CPZ-HCl release were dependent on a size and amount of drugs in the nanoparticles.

Development and characterization of lutein-loaded SNEDDS for enhanced absorption in Caco-2 cells

A self-nanoemulsifying drug delivery system (SNEDDS) has been developed for enhanced oral bioavailability of lutein. Its permeation enhancement has been evaluated using monolayers of Caco-2 cells. SNEDDS is composed of a mixture of Lexol® and Emulmetik® 900, Labrasol®, and Tween 80 as oil, surfactant and co-surfactant, respectively. Upon dilution of lutein-loaded SNEDDS with water, a nanoemulsion was obtained in <10 s with spherical droplets of 40-150 nm in diameter. The zeta potential was in the range of -19 to -32 mV. Increasing the ratio of surfactant to co-surfactant decreased the mean droplet size. Dissolution studies showed that lutein was released rapidly (<5 min) from SNEDDS into 0.1 N HCl and pH 6.8 phosphate buffer solution without any aggregation. In vitro studies using Caco-2 cells revealed that lutein-loaded SNEDDS showed shorter lag time and greater (2-fold) cellular accumulation compared with the lutein dispersion.

Potentials and challenges in self-nanoemulsifying drug delivery systems

INTRODUCTION

A significant number of new chemical entities (almost 40%), that are outcome of contemporary drug discovery programs, have a potential therapeutic promise for patient, as they are highly potent but poorly water soluble resulting in reduced oral bioavailability. Self-nanoemulsifying drug delivery systems (SNEDDS) have emerged as a vital strategy to formulate these poorly soluble compounds for bioavailability enhancement.

AREAS COVERED

The review gives an insight about potential of SNEDDS with regards to oral drug delivery. The effect of various key constituents on formulation of SNEDDS and their applications in oral drug delivery is also discussed. Various aspects of formulation, characterization and biopharmaceutical aspects of SNEDDS are also been explored. The choice and selection of excipients for development of SNEDDS is also discussed.

EXPERT OPINION

The ability of SNEDDS to present the drug in single unit dosage form either as soft or hard gelatin capsule with enhanced solubility maintaining the uniformity of dose is unique. With the ease of large-scale production, high drug-loading capacity, improvement in release behavior of poorly water-soluble drugs and improvement of oral bioavailability, SNEDDS have emerged as preferable system for the formulation of drug compounds with bioavailability problems due to poor aqueous solubility.