Development and Permeability Testing of Self-Emulsifying Atorvastatin Calcium Pellets and Tablets of Compressed Pellets

Nanoemulsions: summary of a decade of research and recent advances

Nanoemulsions consist of a combination of several components such as oil, water, emulsifiers, surfactants and cosurfactants. Various techniques for producing nanoemulsions include high-energy and low-energy approaches such as high-pressure homogenization, microfluidization, jet disperser and phase inversion methods. The properties of a formulation can be influenced by elements such as the composition, concentration, size and charge of droplets, which in turn can affect the technique of manufacture. Characterization is conducted by the assessment of several factors such as physical properties, pH analysis, viscosity measurement and refractive index determination. This article offers a thorough examination of the latest developments in nanoemulsion technology, with a focus on their wide-ranging applications and promising future possibilities. It also discusses the administration of nanoemulsions through several methods.

Preferential Solvation Study of Rosuvastatin in the {PEG400 (1) + Water (2)} Cosolvent Mixture and GastroPlus Software-Based In Vivo Predictions

Rosuvastatin (RST) is a poorly water-soluble drug responsible for limited in vivo dissolution and subsequently low oral systemic absorption (poor bioavailability). The mole fraction solubility values of RST in various ratios of binary mixtures "{PEG400 (1) + water (2)}" at 298.15 K were employed to investigate the preferential solvation (PS) of RST (3) by the binary components. Moreover, the GastroPlus program predicted the drug dissolution/absorption rates, plasma drug concentration, and compartmental regional drug absorbed from a conventional tablet as compared to the RST-loaded (PEG400 + water) mixture (at x ₁ = 0.5) in healthy subjects (considering the fast condition). Fedors' method was adopted to estimate the values of molar volume (314.8 cm³·mol^-1) and Hildebrand solubility parameter (28.08 MPa^1/2) of RST. The results of inverse Kirkwood-Buff integrals showed the PS of RST by PEG400 as observed in all studied ratios of the binary mixture. The highest PS value (δx _1,3 = 1.65 × 10^-2) for RST by PEG400 was attained at x ₁ = 0.5. Finally, the GastroPlus program predicted the maximum dissolution rate [20 mg within 15 min as compared to pure RST (1.5 mg within 15 min)]. Moreover, the program predicted increased in vivo oral absorption (1.2 μg/mL) and enhanced regional absorption (95.3%) of RST from upper segments of the gastrointestinal tract for the RST-loaded PEG400 + water mixture in humans as compared to conventional tablets (87.5% as total regional absorption and 0.88 μg/mL as in vivo absorption). Hence, the present binary system ferrying RST can be a promising strategy to control systemic dyslipidemia after oral or subcutaneous administration.

SEDEX-Self-Emulsifying Delivery Via Hot Melt Extrusion: A Continuous Pilot-Scale Feasibility Study

The aim of this study was to develop a continuous pilot-scale solidification and characterization of self-emulsifying drug delivery systems (SEDDSs) via hot melt extrusion (HME) using Soluplus^® and Kollidon^® VA-64. First, an oil-binding capacity study was performed to estimate the maximal amount of SEDDSs that the polymers could bind. Then, HME was conducted using a Coperion 18 mm ZSK18 pilot plant-scale extruder with split-feeding of polymer and SEDDS in 10, 20, and 30% w/w SEDDSs was conducted. The prepared extrudates were characterized depending on appearance, differential scanning calorimetry, wide-angle X-ray scattering, emulsification time, droplet size, polydispersity index, and cloud point. The oil-binding studies showed that the polymers were able to bind up to 50% w/w of liquid SEDDSs. The polymers were processed via HME in a temperature range between 110 and 160 °C, where a plasticizing effect of the SEDDSs was observed. The extrudates were found to be stable in the amorphous state and self-emulsified in demineralized water at 37 °C with mean droplet sizes between 50 and 300 nm. A cloud point and phase inversion were evident in the Soluplus^® samples. In conclusion, processing SEDDSs with HME could be considered a promising alternative to the established solidification techniques as well as classic amorphous solid dispersions for drug delivery.

Lipid-based solubilization technology via hot melt extrusion: promises and challenges

INTRODUCTION

Self-emulsifying drug delivery systems (SEDDS) are a promising strategy to improve the oral bioavailability of poorly water-soluble drugs (PWSD). The excipients of SEDDS enable permeation through the mucus and gastro-intestinal barrier, inhibiting efflux transporters (e.g. P-glycoprotein) of drugs. Poor drug loading capacity and formulation instability are the main setbacks of traditional SEDDS. The use of polymeric precipitation inhibitors was shown to create supersaturable SEDDS with increased drug payload, and their solidification can help to overcome the instability challenge. As an alternative to several existing SEDDS solidification technologies, hot melt extrusion (HME) holds the potential for lean and continuous manufacturing of supersaturable solid-SEDDS. Despite being ubiquitously applied in solid lipid and polymeric processing, HME has not yet been widely considered for the preparation of SEDDS.

AREAS COVERED

The review begins with the rationale why SEDDS as the preferred lipid-based delivery systems (LBDS) is suitable for the oral delivery of PWSD and discusses the common barriers to oral administration. The potential of LBDS to surmount them is discussed. SEDDS as the flagship of LBDS for PWSD is proposed with a special emphasis on solid-SEDDS. Finally, the opportunities and challenges of HME from the lipid-based excipient (LBE) processing and product performance standpoint are highlighted.

EXPERT OPINION

HME can be a continuous, solvent-free, cost-effective, and scalable technology for manufacturing solid supersaturable SEDDS. Several critical formulations and process parameters in successfully preparing SEDDS via HME are identified.

Solid self emulsifying drug delivery system: Superior mode for oral delivery of hydrophobic cargos

A significant proportion of recently approved drug molecules possess poor aqueous solubility which further restrains their desired bioavailability. Poor aqueous solubility of these drugs poses significant hurdles in development of novel drug delivery systems and achieving target response. Self-emulsifying drug delivery systems (SEDDS) emerged as an insightful approach for delivering highly hydrophobic entities to enhance their bioavailability. Conventional SEDDS were developed in a liquid form which owned numerous shortcomings like low stability and drug loading efficiency, fewer choices of dosage forms and irreversible precipitation of drug or excipients. To address these curbs solid-SEDDS (S-SEDDS) was introduced as an efficient strategy that combined advantages of solid dosage forms such as increased stability, portability and patient compliance along with substantial improvement in the bioavailability. S-SEDDS are isotropic mixtures of oil, surfactant, solvent and co-solvents generated by solidification of liquid or semisolid self-emulsifying ingredients onto powders. The present review highlights components of S-SEDDS, their peculiarities to be considered while designing solid dosage forms and various methods of fabrication. Lastly, key challenges faced during development, applications and future directions for the research in this area are thoroughly summarized.

Atorvastatin Solid Lipid Nanoparticles as a Promising Approach for Dermal Delivery and an Anti-inflammatory Agent

In the current research, the main focus was to overcome dermal delivery problems of atorvastatin. To this end, atorvastatin solid lipid nanoparticles (ATR-SLNs) were prepared by ultra-sonication technique. The prepared SLNs had a PDI value of ≤ 0.5, and the particle size of nanoparticles was in the range 71.07 ± 1.72 to 202.07 ± 8.40 nm. It was noticed that, when the concentration of lipid in ATR-SLNs increased, the size of nanoparticles and drug entrapment efficiency were also increased. Results showed that a reduction in the HLB of surfactants used in the preparation of SLN caused an increase in the particle size, zeta potential (better stability), and drug entrapment efficiency. Despite Tween and Span are non-ionic surfactants, SLNs containing these surfactants showed a negative zeta potential, and the absolute zeta potential increased when the concentration of Span 80 was at maximum. DSC thermograms, FTIR spectra, and x-ray diffraction (PXRD) pattern showed good incorporation of ATR in the nanoparticles without any chemical interaction. In vitro skin permeation results showed that SLN containing atorvastatin was capable of enhancing the dermal delivery of atorvastatin where a higher concentration of atorvastatin can be detected in skin layers. This is a hopeful promise which could be developed for clinical studies of the dermal delivery of atorvastatin nanoparticles as an anti-inflammatory agent.

Piperine fast disintegrating tablets comprising sustained-release matrix pellets with enhanced bioavailability: formulation, in vitro and in vivo evaluation

Piperine (Pip) has been widely studied for its multiple activities such as antidepressant, anti-epileptic, and so forth. However, the poor water solubility coupled with low bioavailability may inevitably hinder the application of Pip in the clinical setting. In this study, a formulation strategy was proposed to spontaneously resolve the low bioavailability and dose dividing issue of Pip. The matrix pellets (Pip-SR-pellets) consisting of Pip solid dispersion (Pip-SD) and hydroxypropylmethyl cellulose-K100 were developed to achieve an increased and sustained release profile in vitro. The Pip-SR-pellets were compacted into fast disintegrating tablets (FDTs) with a blend of excipients comprising lactose, MCC, LS-HPC, and CMS-Na. The Pip-SD was characterized by solubility study and XRD. The evaluation of the cross-sectional morphology of the Pip-FDTs via scanning electron microscope proved that Pip-SR-pellets maintained its structural integrity during compression and were uniformly distributed in the Pip-FDTs. The release profile of Pip-SR-pellets was highly consistent with the Pip-FDTs. In vivo pharmacokinetics study demonstrated that the relative bioavailability of Pip-SR-pellets was approximately 2.70-fold higher than that of the pure drug, and 1.62-fold compared with that of Pip-SD. This work therefore showed a potential industrialized method could be applied to formulate poorly water-soluble drug that has dose-dividing requirement.