Statistical modeling, optimization and characterization of solid self-nanoemulsifying drug delivery system of lopinavir using design of experiment

Solid Self Nano-Emulsifying Drug Delivery System of Dasatinib: Optimization, In-vitro, Ex-vivo and In-vivo assessment

Aim: Dasatinib (DST) is an oral tyrosine kinase inhibitor with poor aqueous solubility. To outwit this issue, a solid self-nano emulsifying drug delivery system (S-SNEDDS) of DST was formulated.Methods: I-optimal mixture design was used for optimization of DST-loaded SNEDDS using Linalool, Cremophor RH40 and Transcutol P. S-SNEDDS underwent physicochemical characterization, in-vitro release and ex-vivo permeation, cell-based assays and pharmacokinetic study.Results: DST-S-SNEDDS showed globule size and PDI of 141.53 ± 5.371 nm and 0.282 ± 0.020, respectively. DST-S-SNEDDS revealed significantly lower IC50 (1.825 μg/mL) than free DST (7.298 μg/mL) in MDA-MB-231. In-vivo pharmacokinetic study revealed 1.94-fold increment in AUC0-t for the DST-S-SNEDDS group than free DST.Conclusion: S-SNEDDS could be promising approach for improving bioavailability and efficacy of DST.

In Vitro and In Vivo testing of 3D-Printed Amorphous Lopinavir Printlets by Selective Laser Sinitering: Improved Bioavailability of a Poorly Soluble Drug

The aim of this paper was to investigate the effects of formulation parameters on the physicochemical and pharmacokinetic (PK) behavior of amorphous printlets of lopinavir (LPV) manufactured by selective laser sintering 3D printing method (SLS). The formulation variables investigated were disintegrants (magnesium aluminum silicate at 5-10%, microcrystalline cellulose at 10-20%) and the polymer (Kollicoat® IR at 42-57%), while keeping printing parameters constant. Differential scanning calorimetry, X-ray powder diffraction, and Fourier-transform infrared analysis confirmed the transformation of the crystalline drug into an amorphous form. A direct correlation was found between the disintegrant concentration and dissolution. The dissolved drug ranged from 71.1 ± 5.7% to 99.3 ± 2.7% within 120 min. A comparative PK study in rabbits showed significant differences in the rate and extent of absorption between printlets and compressed tablets. The values for Tmax, Cmax, and AUC were 4 times faster, and 2.5 and 1.7 times higher in the printlets compared to the compressed tablets, respectively. In conclusion, the SLS printing method can be used to create an amorphous delivery system through a single continuous process.

Self-nanoemulsifying drug delivery system (SNEDDS) of docetaxel and carvacrol synergizes the anticancer activity and enables safer toxicity profile: optimization, and in-vitro, ex-vivo and in-vivo pharmacokinetic evaluation

Docetaxel (DTX) is a first-line chemotherapeutic molecule with a broad-spectrum anticancer activity. On the other hand, carvacrol (CV) has anti-inflammatory, antioxidant, cytotoxic, and hepatoprotective properties that could reduce undue toxicity caused by DTX chemotherapy. Thus, in order to overcome the challenges posed by DTX's poor aqueous solubility, low permeability, hepatic first pass, and systemic toxicities, we have developed a novel solid self-nanoemulsifying drug delivery system (S-SNEDDS) co-loaded with DTX and CV. In the present investigation, liquid-SNEDDS (L-SNEDDS) were fabricated using Nigella sativa oil, Cremophor RH 40, and Ethanol which was converted into solid by lyophilization using Aerosil 200. The reconstituted CV-DTX-S-SNEDDS showed an average globule size of < 200 nm with promising flow properties (angle of repose θ: 33.22 ± 0.06). Additionally, 2.3-fold higher dissolution of DTX was observed from CV-DTX-S-SNEDDS after 6 h as compared to free DTX. Similar trend was followed in dialysis release experiments with 1.5-fold higher release within 24 h. Ex vivo permeation studies demonstrated significantly increased permeation of 1077.02 ± 12.72 μg/cm2 of CV-DTX-S-SNEDDS after 12 h. In vitro cell cytotoxicity studies revealed 5.2-fold reduction in IC50 as compared to free DTX in MDA-MB-231 cells. Formulation was able to induce higher apoptosis in cells treated with CV-DTX-S-SNEDDS as compared to free DTX and CV. It was evident from toxicity studies that CV-DTX-S-SNEDDS was well tolerated at higher dose where CV was able to manage the toxic effects of free DTX. In vivo pharmacokinetic study showed 3.4-fold increased Cmax and improved oral bioavailability as compared to free DTX. Thus, CV-DTX-S-SNEDDS could be an encouraging option for facilitating DTX oral therapy.

Development and pharmacokinetic evaluation of Neusilin® US2-based S-SNEDDS tablets for bosentan: Fasted and fed states bioavailability, IVIS® real-time biodistribution, and ex-vivo imaging

The study reported here aimed to develop and optimize the S-SNEDDS tablet of bosentan (BOS) and to investigate its pharmacokinetic and biodistribution properties. The BOS-loaded SNEDDS have been developed and characterized in a previous study. The BOS-loaded SNEDDS formulation was converted to S-SNEDDS using Neusilin® US2. The S-SNEDDS tablets were obtained using the direct compression technique, and in vitro dissolution, in vitro lipolysis, and ex-vivo permeability studies of the tablets were performed. The S-SNEDDS tablet and reference tablet (Tracleer®) were administered to male Wistar rats at 50 mg/kg dose by oral gavage in fasted and fed state conditions. The biodistribution of the S-SNEDDS tablet was investigated in Balb/c mice using fluorescent dye. The tablets were dispersed in distilled water before administration to animals. The relationship between in vitro dissolution data and in vivo plasma concentration was examined. The S-SNEDDS tablets showed 2.47, 7.49, 3.70, and 4.39 increases in the percentages of cumulative dissolution in FaSSIF, FeSSIF, FaSSIF-V2, and FeSSIF-V2, respectively, when compared to the reference, and increased the Cmax and AUC 2.65 and 1.28-fold and 4.73 and 2.37-fold in fasted and fed states, respectively, when compared to the reference. S-SNEDDS tablets also significantly reduced interindividual variability in both fasted and fed states (p < 0.05). The XenoLight™ DiR and VivoTag® 680XL labeled S-SNEDDS tablet formulation increased the real-time biodistribution in the body by factors of 2.4 and 3.4 and organ uptake and total emission increased by factors of 2.8 and 3.1, respectively. The IVIVR has been successfully established for S-SNEDDS tablets (R2 > 0.9). The present study confirms the potential of the S-SNEDDS tablet to enhance the in vitro and in vivo performance of BOS.

Development of Lipid Polymer Hybrid Drug Delivery Systems Prepared by Hot-Melt Extrusion

This study sought to develop polymer-lipid hybrid solid dispersions containing the poorly soluble drug lopinavir (LPV) by hot-melt extrusion (HME). Hence, the lipid and polymeric adjuvants were selected based on miscibility and compatibility studies. Film casting was used to assess the miscibility, whereas thermal, spectroscopic, and chromatographic analyses were employed to evaluate drug-excipient compatibility. Extrudates were obtained and characterized by physicochemical tests, including in vitro LPV dissolution. Preformulation studies led to select the most appropriate materials, i.e., the polymers PVPVA and Soluplus®, the plasticizers polyethylene glycol 400 and Kolliphor® HS15, phosphatidylcholine, and sodium taurodeoxycholate. HME processing did not result in LPV degradation and significantly increased entrapment efficiency (93.8% ± 2.8 for Soluplus® extrudate against 19.8% ± 0.5 of the respective physical mixture). LPV dissolution was also increased from the extrudates compared to the corresponding physical mixtures (p < 0.05). The dissolution improvement was considerably greater for the Soluplus®-based formulation (24.3 and 2.8-fold higher than pure LPV and PVPVA-based extrudate after 120 min, respectively), which can be attributed to the more pronounced effects of HME processing on the average size and LPV solid-state properties in the Soluplus® extrudates. Transmission electron microscopy and chemical microanalysis suggested that the polymer-lipid interactions in Soluplus®-based formulation depended on thermal processing.

Superior possibilities and upcoming horizons for nanoscience in COVID-19: noteworthy approach for effective diagnostics and management of SARS-CoV-2 outbreak

The outbreak of COVID-19 has caused great havoc and affected many parts of the world. It has imposed a great challenge to the medical and health fraternity with its ability to continue mutating and increasing the transmission rate. Some challenges include the availability of current knowledge of active drugs against the virus, mode of delivery of the medicaments, its diagnosis, which are relatively limited and do not suffice for further prognosis. One recently developed drug delivery system called nanoparticles is currently being utilized in combating COVID-19. This article highlights the existing methods for diagnosis of COVID-19 such as computed tomography scan, reverse transcription-polymerase chain reaction, nucleic acid sequencing, immunoassay, point-of-care test, detection from breath, nanotechnology-based bio-sensors, viral antigen detection, microfluidic device, magnetic nanosensor, magnetic resonance platform and internet-of-things biosensors. The latest detection strategy based on nanotechnology, biosensor, is said to produce satisfactory results in recognizing SARS-CoV-2 virus. It also highlights the successes in the research and development of COVID-19 treatments and vaccines that are already in use. In addition, there are a number of nanovaccines and nanomedicines currently in clinical trials that have the potential to target COVID-19.

Development of a sorafenib-loaded solid self-nanoemulsifying drug delivery system: Formulation optimization and characterization of enhanced properties

Sorafenib, marketed under the brand name Nexavar®, is a multiple tyrosine kinase inhibitor drug that has been actively used in the clinical setting for the treatment of several cancers. However, the low solubility and bioavailability of sorafenib constitute a significant barrier to achieving a good therapeutic outcome. We developed a sorafenib-loaded self-nanoemulsifying drug delivery system (SNEDDS) formulation composed of capmul MCM, tween 80, and tetraglycol, and demonstrated that the SNEDDS formulation could improve drug solubility with excellent self-emulsification ability. Moreover, the sorafenib-loaded SNEDDS exhibited anticancer activity against Hep3B and KB cells, which are the most commonly used hepatocellular carcinoma and oral cancer cell lines, respectively. Subsequently, to improve the storage stability and to increase the possibility of commercialization, a solid SNEDDS for sorafenib was further developed through the spray drying method using Aerosil® 200 and PVP K 30. X-ray diffraction and differential scanning calorimeter data showed that the crystallinity of the drug was markedly reduced, and the dissolution rate of the drug was further improved in formulation in simulated gastric and intestinal fluid conditions. In vivo study, the bioavailability of the orally administered formulation increases dramatically compared to the free drug. Our results highlight the use of the solid-SNEDDS formulation to enhance sorafenib's bioavailability and outlines potential translational directions for oral drug development.

Tadalafil-Loaded Self-Nanoemulsifying Chewable Tablets for Improved Bioavailability: Design, In Vitro, and In Vivo Testing

This research aimed to develop innovative self-nanoemulsifying chewable tablets (SNECT) to increase oral bioavailability of tadalafil (TDL), a nearly insoluble phosphodiesterase-5 inhibitor. Cinnamon essential oil, PEG 40 hydrogenated castor oil (Cremophor® RH 40), and polyethylene glycol 400 served as the oil, surfactant, and cosurfactant in the nanoemulsifying system, respectively. Primary liquid self-nanoemulsifying delivery systems (L-SNEDDS) were designed using phase diagrams and tested for dispersibility, droplet size, self-emulsifying capability, and thermodynamic stability. Adsorption on a carrier mix of silicon dioxide and microcrystalline cellulose was exploited to solidify the optimum L-SNEDDS formulation as self-nanoemulsifying granules (SNEG). Lack of crystalline TDL within the granules was verified by DSC and XRPD. SNEG were able to create a nanoemulsion instantaneously (165 nm), a little larger than the original nanoemulsion (159 nm). SNECT were fabricated by compressing SNEG with appropriate excipients. The obtained SNECT retained their quick dispersibility dissolving 84% of TDL within 30 min compared to only 18% dissolution from tablets of unprocessed TDL. A pharmacokinetic study in Sprague−Dawley rats showed a significant increase in Cmax (2.3-fold) and AUC0−24 h (5.33-fold) of SNECT relative to the unprocessed TDL-tablet (p < 0.05). The stability of TDL-SNECT was checked against dilutions with simulated GI fluids. In addition, accelerated stability tests were performed for three months at 40 ± 2 °C and 75% relative humidity. Results revealed the absence of obvious changes in size, PDI, or other tablet parameters before and after testing. In conclusion, current findings illustrated effectiveness of SNECT to enhance TDL dissolution and bioavailability in addition to facilitating dose administration.

Bioavailability Enhancement Techniques for Poorly Aqueous Soluble Drugs and Therapeutics

The low water solubility of pharmacoactive molecules limits their pharmacological potential, but the solubility parameter cannot compromise, and so different approaches are employed to enhance their bioavailability. Pharmaceutically active molecules with low solubility convey a higher risk of failure for drug innovation and development. Pharmacokinetics, pharmacodynamics, and several other parameters, such as drug distribution, protein binding and absorption, are majorly affected by their solubility. Among all pharmaceutical dosage forms, oral dosage forms cover more than 50%, and the drug molecule should be water-soluble. For good therapeutic activity by the drug molecule on the target site, solubility and bioavailability are crucial factors. The pharmaceutical industry’s screening programs identified that around 40% of new chemical entities (NCEs) face various difficulties at the formulation and development stages. These pharmaceuticals demonstrate less solubility and bioavailability. Enhancement of the bioavailability and solubility of drugs is a significant challenge in the area of pharmaceutical formulations. According to the Classification of Biopharmaceutics, Class II and IV drugs (APIs) exhibit poor solubility, lower bioavailability, and less dissolution. Various technologies are discussed in this article to improve the solubility of poorly water-soluble drugs, for example, the complexation of active molecules, the utilization of emulsion formation, micelles, microemulsions, cosolvents, polymeric micelle preparation, particle size reduction technologies, pharmaceutical salts, prodrugs, the solid-state alternation technique, soft gel technology, drug nanocrystals, solid dispersion methods, crystal engineering techniques and nanomorph technology. This review mainly describes several other advanced methodologies for solubility and bioavailability enhancement, such as crystal engineering, micronization, solid dispersions, nano sizing, the use of cyclodextrins, solid lipid nanoparticles, colloidal drug delivery systems and drug conjugates, referring to a number of appropriate research reports.

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.

Combination of lipid nanoparticles and iontophoresis for enhanced lopinavir skin permeation: Impact of electric current on lipid dynamics

Nanostructured lipid carriers (NLC)-loaded with lopinavir (LPV) were developed for its iontophoretic transdermal delivery. Electronic paramagnetic resonance (EPR) spectroscopy of fatty acid spin labels and differential scanning calorimetry (DSC) were applied to investigate the lipid dynamic behavior of NLC before and after the electrical current. In vitro release and permeation studies, with and without anodic and cathodic iontophoresis were also performed. NLC-LPV had nanometric size (179.0 ± 2.5 nm), high drug load (∼x223C 4.14%) and entrapment efficiency (EE) (∼x223C 80%). NLC-LPV was chemically and physically stable after applying an electric current. The electrical current reduced EE after 3 h (67.21 ± 2.64%), resulting in faster LPV in vitro release. EPR demonstrated that iontophoresis decreased NLC lipid dynamics, which is a long-lasting effect. DSC studies demonstrated that electrical current could trigger the polymorphic transition of NLC and drug solubilization in the lipid matrix. NLC-LPV, combined with iontophoresis, allowed drug quantification in the receptor medium, unlike unloaded drugs. Cathodic iontophoresis enabled the quantification of about 7.9 µg/cm² of LPV in the receptor medium. Passive NLC-LPV studies had to be done for an additional 42 h to achieve similar concentrations. Besides, anodic iontophoresis increased by 1.8-fold the amount of LPV in the receptor medium, demonstrating a promising antiviral therapy strategy.

Quality-by-Design-Based Development of a Voxelotor Self-Nanoemulsifying Drug-Delivery System with Improved Biopharmaceutical Attributes

Low aqueous solubility and poor oral bioavailability are limiting factors in the oral delivery of voxelotor, an antisickling agent. To overcome these limitations, a voxelotor self-nanoemulsifying drug delivery system was developed. Various oils, surfactants, and cosurfactants were screened for their solubilization potential for the drug. The area of nanoemulsification was identified using a ternary phase diagram. An experimental mixture design and a desirability function were applied to select SNEDDSs that contain a maximum amount of lipids and a minimum amount of surfactant, and that possess optimal emulsification properties (i.e., droplet sizes, polydispersity index (PDI), emulsification time, and transmittance percentage). The optimized SNEDDS formulation was evaluated for the self-emulsifying time (32 s), droplet size (35 nm), and zeta potential (−8 mV). In vitro dissolution studies indicated a 3.1-fold improvement in drug solubility from the optimized SNEDDS over pure drug powder. After 60 min of in vitro lipolysis, 88% of the voxelotor loaded in the SNEDDS remained in the aqueous phase. Cytotoxicity evaluation, using Caco-2 cells, indicated the safety of the formulation at 0.9 mg/mL. The transport of the voxelotor SNEDDS across Caco-2 monolayers was significantly enhanced compared to that of the free drug. Compared to the drug suspension, the developed SNEDDS enhanced the oral bioavailability (1.7-fold) of voxelotor in rats. The results suggest that further development of SNEDDSs for the oral delivery of voxelotor is needed.

Repurposed drug against COVID-19: nanomedicine as an approach for finding new hope in old medicines

The coronavirus disease 2019 (COVID-19) has become a threat to global public health. It is caused by the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) and has triggered over 17 lakh causalities worldwide. Regrettably, no drug or vaccine has been validated for the treatment of COVID-19 and standard treatment for COVID-19 is currently unavailable. Most of the therapeutics moieties which were originally intended for the other disease are now being evaluated for the potential to be effective against COVID-19 (re-purpose). Nanomedicine has emerged as one of the most promising technologies in the field of drug delivery with the potential to deal with various diseases efficiently. It has addressed the limitations of traditional repurposed antiviral drugs including solubility and toxicity. It has also imparted enhanced potency and selectivity to antivirals towards viral cells. This review emphasizes the scope of repositioning of traditional therapeutic approaches, in addition to the fruitfulness of nanomedicine against COVID-19.

Development of stable amorphous solid dispersion and quantification of crystalline fraction of lopinavir by spectroscopic-chemometric methods

This study aimed to improve the dissolution of the poorly soluble drug lopinavir (LPV) by preparing amorphous solid dispersions (ASDs) using solvent evaporation method. The ASD formulations were prepared with ternary mixtures of LPV, Eudragit® E100, and microcrystalline cellulose (MCC) at various weight ratios. The ASDs were subjected to solid-state characterization and in vitro drug dissolution testing. Chemometric models based on near infrared spectroscopy (NIR) and NIR-hyperspectroscopy (NIR-H) data were developed using the partial least squares (PLS) regression and externally validated to estimate the percent of the crystalline LPV in the ASD. Initially, the solid-state characterization data of ASDs showed transformation of the drug from crystalline to amorphous. Negligible fraction of crystalline LPV was present in the ASD (3%). Compared to pure LPV, ASDs showed faster and higher drug dissolution (<2% vs. 60.3-73.5%) in the first 15 min of testing. The ASD was stable against crystallization during stability testing at 40 °C/75% for a month. In conclusion, the prepared ASD was stable against devitrification and enhance the dissolution of LPV.

Formulation and In Vivo Evaluation of Ticagrelor Self-nanoemulsifying Drug Delivery Systems

BACKGROUND

Ticagrelor (TGR), being an antiplatelet agent, belongs to BCS class IV drug with low solubility and permeability that undergoes first-pass metabolism, leading to reduced bioavailability of 36%.

OBJECTIVE

The main objective of this study is to develop TGR SNEDDS for enhancing solubility and oral bioavailability.

METHODS

An oil, surfactant and co-surfactant (miglyol 810, brij 35 and lauro glycol FCC) are chosen based on the maximum solubility of TGR. The selected vehicles are mixed in different ratios and are agitated mildly. Transmittance values that are more than 80 were noted and are used for constructing pseudo ternary phase diagram. Formulations that passed stability testing were evaluated for % transmission, drug content and in vitro drug release analysis. In vivo bioavailability studies of optimized SNEDDS are performed in Wistar rats.

RESULTS

From evaluation studies of TGR, formulation F13 with maximum drug release of 98.99% in 60 minutes, that is higher than 31.99% of the pure drug is considered as an optimised formulation. The particle size, Z average and zeta potential of the optimized TGR formulation F13 was 289.6 nm, 185.1 nm and -18.3 mV respectively. The FTIR and SEM studies do not indicate any drug excipient interaction and confirm nano size which is stable for 3 months. From in vivo bioavailability studies in rats, the C_max of optimized TGR SNEDDS (302.43±4.78 ng/ml) is higher than pure TGR suspension (47.32±2.75 ng/ml) and optimized SNEDDS exhibited 5 folds increase in oral bioavailability when compared to pure drug.

CONCLUSION

Hence the results reveal that, application of SNEDDS formulation technique for TGR Increases solubility and oral bioavailability.

Polyethylene glycol (5,000) succinate conjugate of lopinavir and its associated toxicity using Danio rerio as a model organism

Lopinavir (LPV), a well-known drug administered in human immunodeficiency virus (HIV) infection, has shown limitation for pediatric treatment owing to poor aqueous solubility that gives rise to limited oral bioavailability and short plasma half-life (5–6 h). Polymers such as polyethylene glycol (PEG) have been used as drug carriers to improve their solubility. This study reports the preparation of polyethylene glycol (5,000) succinate (PEG–Suc–LPV) conjugate of LPV by the esterification method. The disappearance of the 3,395 cm⁻¹ (O–H stretch of COOH) band for Polyethylene glycol (5,000) succinate (PEG–Suc )confirms the formation ester linkage with the OH group of LPV which is also confirmed by ¹H NMR analysis. The XRD for the conjugate showed a broad, amorphous peak while pure PEG, Suc, LPV are crystalline. DSC analysis showed that the conjugate exhibited new broad and diffuse peaks, confirming that they did exist in an amorphous state as multiple complexes. The conjugate showed improved solubility and activity with reduced toxicity compared to pure LPV. The solubility of LPV increased significantly from 80 to 318 ppm. Furthermore, an aquatic toxicity test using Danio rerio showed that the conjugate had a lower LC₅₀ (60.8 ppm) when compared to the pure LPV drug LC₅₀ (6.42 ppm). These results suggest PEG–Suc conjugate of LPV as an efficient carrier for enhanced hydrophilicity and anti-HIV property of LPV.

Central composite design-based optimization of lopinavir vitamin E-TPGS micelle: In vitro characterization and in vivo pharmacokinetic study

This study was aimed at formulating Lopinavir loaded Vitamin E-TPGS micelles to enhance its oral bioavailability. Lopinavir is an HIV-1 protease inhibitor with low aqueous solubility leading to poor oral bioavailability and thus frequent dosing. Drug loaded micelles were fabricated using thin film hydration technique and optimized by two-factor five-level central composite design. For this purpose independent variables selected were TPGS to drug ratio and rotational speed of rotary evaporator, whereas dependent variables chosen were particle size and % entrapment efficiency. The effect of an independent variable on the dependent variable was studied by generating a quadratic polynomial model. Results of in vitro characterization showed that prepared lopinavir micelles exhibited particle size 91.71 nm, polydispersity index 0.129, zeta potential -24.8 mV, entrapment efficiency 99.36 ± 1.06% and drug loading 20.83 ± 1.23%. Results of DSC and P-XRD evaluation revealed that drugs were successfully encapsulated inside the Vitamin E-TPGS micelles. In vitro release studies displayed enhancement in drug dissolution as a result of its loading into micelles. TEM images showed that micelles were spherical. On oral administration of lopinavir micelles; the relative bioavailability was boosted by 3.17 folds compared to lopinavir suspensions. Thus, we can conclude that TPGS based micelles possess the prodigious potential to overcome the challenges of current HAART therapy.

Nanoformulated Eudragit lopinavir and preliminary release of its loaded suppositories

The development of novel paediatrics formulations is critical towards achieving the UNAIDS 90-90-90 targets. According to the latest UNAIDS reports, the availability of antiretrovirals (ARVs) for children has increased significantly, from 49% in 2015 to 53% in 2017. However, this percentage is considerably lower than the 80% for pregnant women that are currently on treatment. Therefore, there is still an urgent need for an alternative child-friendly delivery system. Lopinavir (LPV) is a protease inhibitor first-line HIV treatment drugs but suffers from low aqueous solubility, bitter state, short half-life leading to a limited dissolution and variable bioavailability upon oral administration. This work focused on the fabrication and characterization of a delivery system entailing Eudragit RSPO-LPV nanoparticles loaded suppositories in two different bases to improve the bioavailability and overcome the problem encountered through oral administration emanating from poor solubility. The prepared nanoparticles by nanoprecipitation method were characterized and compounded into suppositories in fattibase and polyethylene glycol (PEG) bases using a melt fusion method. The suppositories were stored at 5 and 25 °C, and were sampled at 0, 4, 8, 12 weeks. The samples were assessed by particle size, entrapment efficiency (EE), zeta potential and polydispersity index (PDI) variations. The preliminary in vitro release studies were analysed by HPLC. The nanoparticles have an average particle size of 191 nm with spherical morphology, entrapment efficiency, polydispersity index and zeta potential of 79.0 ± 0.5%, 0.224, and 25.87 ± 0.41 mV respectively. The surface analysis of the nanoparticles with FTIR, SEM, PXRD and TGA indicated that the drug was truly encapsulated without any interaction. The in vitro release studies showed that a better release was observed in suppositories formulated with PEG than the fattibase by having higher drug concentration released. Hence, this rectal formulation might serve as an alternative for paediatric HIV treatment upon further investigation.

Improved Oral Pharmacokinetics of Pentoxifylline with Palm Oil and Capmul® MCM Containing Self-Nano-Emulsifying Drug Delivery System

Pentoxifylline (PTX), an anti-hemorrhage drug used in the treatment of intermittent claudication, is extensively metabolized by the liver resulting in a reduction of the therapeutic levels within a short duration of time. Self-nano-emulsifying drug delivery system (SNEDDS) is well reported to enhance the bio-absorption of drugs by forming nano-sized globules upon contact with the biological fluids after oral administration. The present study aimed to formulate, characterize, and improve the oral bioavailability of PTX using SNEDDS. The formulated SNEDDS consisted of palm oil, Capmul® MCM, and Tween® 80 as oil, surfactant, and co-surfactant, respectively. The mixture design module under the umbrella of the design of experiments was used for the optimization of SNEDDS. The dynamic light-scattering technique was used to confirm the formation of nanoemulsion based on the globule size, in addition to the turbidity measurements. In vivo bioavailability studies were carried out on male Wistar rats. The pharmacokinetic parameters upon oral administration were calculated using the GastroPlus software. The optimized SNEDDS had a mean globule size of 165 nm with minimal turbidity in an aqueous medium. Bioavailability of PTX increased 1.5-folds (AUC = 1013.30 ng h/mL) as SNEDDS than the pure drug with an AUC of 673.10 ng h/mL. In conclusion, SNEDDS was seen to enhance the bioavailability of PTX and can be explored to effectively control the incidents of intermittent claudication.

Techniques for Formulation of Nanoemulsion Drug Delivery System: A Review

Nanoemulsion drug delivery systems are advanced modes for delivering and improving the bioavailability of hydrophobic drugs and the drug which have high first pass metabolism. The nanoemulsion can be prepared by both high energy and low energy methods. High energy method includes high-pressure homogenization, microfluidization, and ultrasonication whereas low energy methods include the phase inversion emulsification method and the self-nanoemulsification method. Low energy methods should be preferred over high energy methods as these methods require less energy, so are more efficient and do not require any sophisticated instruments. However high energy methods are more favorable for food grade emulsion as they require lower quantities of surfactant than low energy methods. Techniques for formulation of nanoemulsion drug delivery system are overlapping in nature, especially in the case of low energy methods. In this review, we have classified different methods for formulation of nanoemulsion systems based on energy requirements, nature of phase inversion, and self-emulsification.

Enhanced Release Kinetics and Stability of Resveratrol Loaded Self Nanoemulsifying Delivery Systems Developed using Experimental Design

Background:

Resveratrol is a member of the stilbene family emerged as a leading candidate for improving healthspan through potentially slowing the aging process and preventing chronic diseases. A number of institutions and scientists specialized in this field across the world are working to develop a promising Self Emulsifying formulation to enhance bioavailability of hydrophobic resveratrol using oil.

Objective:

The objective of the current study is to develop self-nano emulsifying drug delivery systems using long-chain triglycerides of resveratrol to enhance solubility, stability, release kinetics and to overcome low bioavailability.

Methods:

Solubility studies performed in different lipids, surfactants and cosurfactants. Phase diagrams constructed to select the areas of nanoemulsion. SNEDDS formulation was optimized using 33 central composite design considering lipid (X1), surfactant (X2) and co-surfactant (X3) as critical variables, optimized formulation was located using overlay plot.

Results:

The nanometer size and high values of zeta potential depicted non-coalescent nature of SNEDDS. The resulted SNEDDS formulation had improved in vitro release followed by Hixson Crowell model with higher regression R2value 0. 929. Thermodynamic stability studies ascertained stable formulation. Mean droplet size in selected nanocarrier was found to be 83.29 nm. The nanocarriers subjected to 2-8°C (45% RH), 25-30°C (60% RH) and 45-50°C (75% RH) in glass vials exhibited no significant changes in 3 months.

Conclusion:

The novel approach was developed by selecting optimum blends of lipids, surfactants and cosurfactant using central composite design. This study not only offers a good example of augmenting bioavailability of resveratrol but will also provide a promising oral formulation for clinical application.

Quality by Design Enabled Development of Oral Self-Nanoemulsifying Drug Delivery System of a Novel Calcimimetic Cinacalcet HCl Using a Porous Carrier: In Vitro and In Vivo Characterisation

In this present research, work quality by design-enabled development of cinacalcet HCl (CH)-loaded solid self-nanoemulsifying drug delivery system (S-SNEDDS) was conducted using a porous carrier in order to achieve immediate drug release and better oral bioavailability. Capmul MCM (CAP), Tween 20 (TW 20) and Transcutol P (TRP) were selected as excipients. Cumulative % drug release at 30 min (Q30), emulsification times (ET), mean globule size (GS) and polydispersity index (PDI) were identified as critical quality attributes (CQAs). Factor mode effect analysis (FMEA) and Taguchi screening design were applied for screening of factors. The optimised single dose of S-SNEDDS obtained using Box-Behnken design (BBD) consisted of 30 mg of CH, 50 mg of CAP, 149.75 mg of TW 20, 55 mg of TRP and 260.75 mg of Neusilin US2. It showed an average Q30 of 97.6%, ET of 23.3 min, GS of 89.5 nm and PDI of 0.211. DSC, XRD and SEM predict the amorphous form of S-SNEDDS. In vivo pharmacokinetic study revealed better pharmacokinetic parameters of S-SNEDDS. The above study concluded that the optimised S-SNEDDS is effective to achieve the desired objective. Graphical Abstract.

Bioadhesive Food Protein Nanoparticles as Pediatric Oral Drug Delivery System

The goal of this study was to develop bioadhesive food protein nanoparticles using zein (Z), a hydrophobic corn protein, as the core and whey protein (WP) as the shell for oral pediatric drug delivery applications. Lopinavir (LPV), an antiretroviral drug, and fenretinide, an investigational anticancer agent, were used as model drugs in the study. The particle size of ZWP nanoparticles was in the range of 200-250 nm, and the drug encapsulation efficiency was >70%. The nanoparticles showed sustained drug release in simulated gastrointestinal fluids. ZWP nanoparticles enhanced the permeability of LPV and fenretinide across Caco-2 cell monolayers. In both ex vivo and in vivo studies, ZWP nanoparticles were found to be strongly bioadhesive. ZWP nanoparticles enhanced the oral bioavailability of LPV and fenretinide by 4 and 7-fold, respectively. ZWP nanoparticles also significantly increased the half-life of both drugs. The nanoparticles did not show any immunogenicity in mice. Overall, the study demonstrates the feasibility of developing safe and effective food protein-based nanoparticles for pediatric oral drug delivery.

Strategic approach to developing a self-microemulsifying drug delivery system to enhance antiplatelet activity and bioavailability of ticagrelor

Background

Ticagrelor (TCG) is used to inhibit platelet aggregation in patients with acute coronary syndrome, but its poor solubility and low bioavailability limit its in vivo efficacy. The purpose of this study was to manufacture an optimized TCG-loaded self-microemulsifying drug delivery system (SMEDDS) to enhance the oral bioavailability and antiplatelet activity of TCG.

Materials and methods

Solubility and emulsification tests were conducted to determine the most suitable oils, surfactants, and cosurfactants. Scheffé's mixture design was applied to optimize the percentage of each component applied in the SMEDDS formulation to achieve optimal physical characteristics, ie, high solubility of TCG in SMEDDS, small droplet size, low precipitation, and high transmittance.

Results

The optimized TCG-loaded SMEDDS (TCG-SM) formulation composed of 10.0% Capmul MCM (oil), 53.8% Cremophor EL (surfactant), and 36.2% Transcutol P (cosurfactant) significantly improving the dissolution of TCG in various media compared with TCG in Brilinta^® (commercial product). TCG-SM exhibited higher cellular uptake and permeability in Caco-2 cells than raw TCG suspension. In pharmacokinetic studies in rats, TCG-SM exhibited higher oral bioavailability with 5.7 and 6.4 times higher area under the concentration-time curve and maximum plasma concentration, respectively, than a raw TCG suspension. Antiplatelet activity studies exhibited that the TCG-SM formulation showed significantly improved inhibition of platelet aggregation compared with raw TCG at the same dose of TCG. And, a 10 mg/kg dose of raw TCG suspension and a 5 mg/kg dose of TCG-SM had a similar area under the inhibitory curve (907.0%±408.8% and 907.8%±200.5%⋅hours, respectively) for antiplatelet activity.

Conclusion

These results suggest that the developed TCG-SM could be successfully used as an efficient method to achieve the enhanced antiplatelet activity and bioavailability of TCG.

Insights on Oral Drug Delivery of Lipid Nanocarriers: a Win-Win Solution for Augmenting Bioavailability of Antiretroviral Drugs

The therapeutic functionality of innumerable antiretroviral drugs is supposedly obscured owing to their low metabolic stability in the gastrointestinal tract and poor solubilization property leading to poor oral bioavailability. Dictated by such needs, lipid-based formulations could be tailored using nanotechnology which would be instrumental in ameliorating the attributes of such drugs. The stupendous advantages which lipid nanocarriers offer including improved drug stability and peroral bioavailability coupled with sustained drug release profile and feasibility to incorporate wide array of drugs makes it a potential candidate for pharmaceutical formulations. Furthermore, they also impart targeted drug delivery thereby widening their arena for use. Therefore, the review will encompass the details pertaining to numerous lipid nanocarriers such as nanoemulsion, solid lipid nanoparticle, nanostructured lipid carriers, and so on. These nanocarriers bear the prospective of improving the mucosal adhesion property of the drugs which ultimately upgrades its pharmacokinetic profile. The biodegradable and physiological nature of the lipid excipients used in the formulation is the key parameter and advocates for their safe use. Nevertheless, these lipid-based nanocarriers are amenable to alterations which could be rightly achieved by changing the excipients used or by modifying the process parameters. Thus, the review will systematically envisage the impending benefits and future perspectives of different lipid nanocarriers used in oral delivery of antiretroviral drugs.

Taste Evaluation by Electronic Tongue and Bioavailability Enhancement of Efavirenz

Self-nanoemulsifying drug delivery systems (SNEDDS) are isotropic and thermodynamically stable mixtures of oil, surfactant, co-surfactant, and drug which emulsify spontaneously on contact with aqueous phase under mild agitation. Efavirenz used for treatment of acquired immune deficiency syndrome, is poorly water soluble and bitter tasting drug resulting in "burning mouth syndrome (BMS)." The objective of this study was to improve solubility and oral bioavailability by formulating liquid-SNEDDS and to mask bitter taste and minimize BMS. Capmul PG8 NF, Cremophor RH40, and Transcutol HP were selected as oil, surfactant, and co-surfactant. Ternary phase diagrams were constructed to evaluate the nanoemulsification region. A 3² factorial design was employed to optimize L-SNEDDS with droplet size and drug release as responses. Optimized batch was subjected to evaluation of taste by human panel method and electronic tongue, cloud point determination, phase separation, in vivo and stability studies. The optimized batch exhibited droplet size of 21.53 nm, polydispersibility index 0.155, and in vitro drug release of 92.26% in 60 min. The in vivo studies revealed 4.5 times enhancement in oral bioavailability. Taste evaluation indicated reduced the intensity and shortened duration of BMS. The formulation was stable at 40°C ± 75% RH after 3 months. Comparison between standard bitter drug and efavirenz in SNEDDS formulation using e-tongue by principal component analysis revealed significant differences in discrimination index, computed by multivariate data analysis. This study demonstrated that L-SNEDDS may be an alternative approach to improve solubility and oral bioavailability and for masking the bitterness of efavirenz.

Self-nanoemulsifying drug delivery system of bruceine D: a new approach for anti-ulcerative colitis

Background

Bruceine D (BD) is a major bioactive component isolated from the traditional Chinese medicinal plant Brucea javanica which has been widely utilized to treat dysentery (also known as ulcerative colitis [UC]).

Methods

To improve the water solubility and absolute bioavailability of BD, we developed a self-nanoemulsifying drug delivery system (SNEDDS) composing of MCT (oil), Solutol HS-15 (surfactant), propylene glycol (co-surfactant) and BD. The physicochemical properties and pharmacokinetics of BD-SNEDDS were characterized, and its anti-UC activity and potential mechanism were evaluated in TNBS-induced UC rat model.

Results

The prepared nanoemulsion has multiple beneficial aspects including small mean droplet size, low polydispersity index (PDI), high zeta potential (ZP) and excellent stability. Transmission electron microscopy showed that nanoemulsion droplets contained uniform shape and size of globules. Pharmacokinetic studies demonstrated that BD-SNEDDS exhibited enhanced pharmacokinetic parameters as compared with BD-suspension. Moreover, BD-SNEDDS significantly restored the colon length and body weight, reduced disease activity index (DAI) and colon pathology, decreased histological scores, diminished oxidative stress, and suppressed TLR4, MyD88, TRAF6, NF-κB p65 protein expressions in TNBS-induced UC rat model.

Conclusion

These results demonstrated that BD-SNEDDS exhibited highly improved oral bioavailability and advanced anti-UC efficacy. In conclusion, our current results provided a foundation for further research of BD-SNEDDS as a potential complementary therapeutic agent for UC treatment.

Pharmaceutical Dispersion Techniques for Dissolution and Bioavailability Enhancement of Poorly Water-Soluble Drugs

Over the past decades, a large number of drugs as well as drug candidates with poor dissolution characteristics have been witnessed, which invokes great interest in enabling formulation of these active ingredients. Poorly water-soluble drugs, especially biopharmaceutical classification system (BCS) II ones, are preferably designed as oral dosage forms if the dissolution limit can be broken through. Minimizing a drug’s size is an effective means to increase its dissolution and hence the bioavailability, which can be achieved by specialized dispersion techniques. This article reviews the most commonly used dispersion techniques for pharmaceutical processing that can practically enhance the dissolution and bioavailability of poorly water-soluble drugs. Major interests focus on solid dispersion, lipid-based dispersion (nanoencapsulation), and liquisolid dispersion (drug solubilized in a non-volatile solvent and dispersed in suitable solid excipients for tableting or capsulizing), covering the formulation development, preparative technique and potential applications for oral drug delivery. Otherwise, some other techniques that can increase the dispersibility of a drug such as co-precipitation, concomitant crystallization and inclusion complexation are also discussed. Various dispersion techniques provide a productive platform for addressing the formulation challenge of poorly water-soluble drugs. Solid dispersion and liquisolid dispersion are most likely to be successful in developing oral dosage forms. Lipid-based dispersion represents a promising approach to surmounting the bioavailability of low-permeable drugs, though the technique needs to traverse the obstacle from liquid to solid transformation. Novel dispersion techniques are highly encouraged to develop for formulation of poorly water-soluble drugs.

Bioavailability enhancement, Caco-2 cells uptake and intestinal transport of orally administered lopinavir-loaded PLGA nanoparticles

Nanoparticles (NPs) can be absorbed via M cells of Peyer's patches after oral delivery leading to passive lymphatic targeting followed by systemic drug delivery. Hence, the study was aimed to formulate PLGA NPs of lopinavir. The NPs were prepared by nanoprecipitation, optimized by 3³ factorial design and characterized by TEM, DSC, FTIR studies and safety was assessed by MTT assay. In vivo pharmacokinetic studies were performed in rats. The NPs were discrete spherical structures having particle size of 142.1 ± 2.13 nm and entrapment of 93.03 ± 1.27%. There was absence of drug-polymer interaction. Confocal images revealed the penetration and absorption of coumarin-loaded NPs in Caco-2 cells and intestine after oral delivery. There was 3.04 folds permeability and 13.9 folds bioavailability enhancement from NPs. The NPs can be promising delivery system for antiretroviral drug by delivering the drug to lymph (major HIV reservoir site) via direct absorption through intestine before reaching systemic circulation.