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

Application of quality by design in optimization of nanoformulations: Principle, perspectives and practices

Nanoparticulate drug delivery systems (NDDS) based nanoformulations have emerged as promising drug delivery systems. Various NDDS-based formulations have been reported such as polymeric nanoparticles (NPs), nanoliposomes, solid lipid NPs, nanocapsules, liposomes, self-nano emulsifying drug delivery systems, pro liposomes, nanospheres, microemulsion, nanoemulsion, gold NPs, silver NPs and nanostructured lipid carrier. They have shown numerous advantages such as enhanced bioavailability, aqueous solubility, permeability, controlled release profile, and blood-brain barrier (BBB) permeability. This advantage of NDDS can help to deliver pure drugs to the target site. However, the formulation of nanoparticles is a complex process that requires optimization to ensure product quality and efficacy. Quality by Design (QbD) is a systemic approach that has been implemented in the pharmaceutical industry to improve the quality and reliability of drug products. QbD involves the optimization of different parameters like zeta potential (ZP), particle size (PS), entrapment efficiency (EE), polydispersity index (PDI), and drug release using statistical experimental design. The present article discussed the detailed role of QbD in optimizing nanoformulations and their advantages, advancement, and applications from the industrial perspective. Various case studies of QbD in the optimization of nanoformulations are also discussed.

Nanoarchitectonics of doxycycline-loaded vitamin E-D-α-tocopheryl polyethylene glycol 1000 succinate micelles for ovarian cancer stem cell treatment

Aim: This study aim to develop doxycycline within the D-α-tocopheryl polyethylene glycol 1000 succinate micelle platform as an anticancer stem cell agent. Materials & methods: The optimized nanomicelle formulation was prepared using the solvent casting method and evaluated through physicochemical and biological characterization. Results: Nanomicelles exhibited mean particle sizes of 14.48 nm (polydispersity index: 0.22) using dynamic light scattering and 18.22 nm using transmission electron micrography. Drug loading and encapsulation efficiency were 2% and 66.73%, respectively. Doxycycline-loaded micelles exhibited sustained release, with 98.5% released in 24 h. IC50 values were 20 μg/ml for free drug and 5 μg/ml for micelles after 48 h of cell exposure. A significant 74% reduction in CD44 biomarker and 100% colony formation inhibition were observed. Conclusion: Doxycycline in hemo/biocompatible nanomicelles holds potential for ovarian cancer stem cell therapy.

Preparation, optimization, and characterization of chrysin-loaded TPGS-b-PCL micelles and assessment of their cytotoxic potential in human liver cancer (Hep G2) cell lines

In total, nine TPGS-b-PCL copolymers were synthesized employing distinct TPGS analogues (TPGS 2000, 3500, and 5000). In these copolymers, the length of the PCL chain varied according to the TPGS to PCL molecular weight ratio (1:1, 1:2, and 1:3). The formulation optimization was done by optimizing the drug to polymer ratio, encapsulation efficiency, drug loading, micelle diameter, and polydispersity index (PDI). TPGS3500-b-PCL7000 copolymer (TPGS to PCL ratio 1:2) with drug to polymer ratio 1:30 showed the best percentage encapsulation (63.50 ± 0.45 %) and drug loading (2.05 ± 0.07). The optimal micelle (CHR-M) diameter and PDI were determined to be 94.57 ± 13.40 nm and 0.16 ± 0.02, respectively. CHR-M showed slow release when compared with alcoholic solution of chrysin. Approximately 70.70 ± 6.4 % drug was released in 72 h. The CHR-M demonstrated considerably greater absorption in Hep G2 cells, which confirmed the reliability of the micellar carrier. The MTT assay results showed that the IC50 values for CHR-M were much lower after 24 and 48 h when compared to free chrysin. Therefore, CHR-M may be a viable carrier for active chrysin targeting with improved anticancer potential. Also, it could be a better alternative for the currently available treatment of hepatocellular carcinoma.

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.

Lopinavir-menthol co-crystals for enhanced dissolution rate and intestinal absorption

Lopinavir is an antiretroviral, antiparasitic agent and recently utilized in treatment of COVID-19. Unfortunately, lopinavir exhibited poor oral bioavailability due to poor dissolution, extensive pre-systemic metabolism, and significant P-glycoprotein intestinal efflux. Accordingly, the aim was to enhance dissolution rate and intestinal absorption of lopinavir. This employed co-processing with menthol which is believed to modify crystalline structures and inhibit intestinal efflux. Lopinavir was mixed with menthol at different molar ratios before ethanol assisted kneading. Formulations were evaluated using FTIR spectroscopy, differential scanning calorimetry (DSC), X-ray powder diffraction (XRD) and dissolution studies. Optimum ratio was utilized to assess lopinavir intestinal permeability. This employed in situ rabbit intestinal perfusion technique. FTIR, DSC and XRD indicated formation of lopinavir-menthol co-crystals at optimum molar ratio of 1:2. Additional menthol underwent phase separation due to possible self-association. Co-crystallization significantly enhanced lopinavir dissolution rate compared with pure drug to increase the dissolution efficiency from 24.96% in case of unprocessed lopinavir to 91.43% in optimum formulation. Lopinavir showed incomplete absorption from duodenum and jejuno-iliac segments with lower absorptive clearance from jejuno-ileum reflecting P-gp efflux. Co-perfusion with menthol increased lopinavir intestinal permeability. The study introduced menthol as co-crystal co-former for enhanced dissolution and augmented intestinal absorption of lopinavir.

Design and characterization of gambogic acid-loaded mixed micelles system for enhanced oral bioavailability

The aim of this study was to develop a gambogic acid-loaded mixed micelles (GA-M) system, using Kolliphor HS15 and lecithin, for enhancement of oral bioavailability. GA-M was prepared using the thin film hydration method, and particle size and zeta potential indexes were used to determine the optimized formulation was optimized with taking particle size, zeta potential as indexes. The optimal GA-M system had a mean particle size in the nanometer range (87.22 ± 0.68 nm) and zeta potential greater than 20 mV in magnitude (-21.63 ± 1.69 mV) at a 1:1 proportion of HS15: lecithin. Additionally, the carriers had a high entrapment efficiency (98.32 ± 3.52%) and drug loading (4.68 ± 0.17%). Furthermore, the in vitro GA release characteristics followed first-order kinetics, suggesting that release of the molecule was achieved both by medium diffusion and structural erosion. Transport elucidation in Caco-2 cells demonstrated that the efflux ratio of encapsulated GA was dramatically decreased from 1.42 to 0.76, and pharmacokinetic studies showed that the oral bioavailability of GA-M was 2.3 times higher than that of free GA, indicating that HS15/lecithin mixed micelles could promote absorption in the gastrointestinal tract. Overall, these results present a micelle system suitable for oral delivery, with increased solubility and oral bioavailability of GA.

Applications of nanoengineered therapeutics and vaccines: special emphasis on COVID-19

Nanomedicine provides innovative strategies that had significantly improved drug and gene delivery and allowed control over the engineering of therapeutics, diagnostics, vaccines, and other medical devices, for a diversity of medical applications. This review focuses on the current attempts to develop potent nanoengineered vaccines and therapeutics against coronaviruses, and the recent fabrication strategies and design principles to control acute infections from the escalating SARS-CoV-2 pandemic. Nanomedical approaches provide versatile platforms that can be utilized to enhance the overall potency, safety, and stability of vaccines, thus augmenting the desired immune response. Their modulable conformational features of size, shape, surface charge, antigen display, and composition allow for precise tuning and optimization of the nanoconstructs for the management of a variety of diseases and pathological conditions. The ability to control the release of their encapsulated cargoes and the possibility of surface decoration with various moieties support the construction of multifunctional nanomaterials that ultimately boost and prolong the immune response elicited and/or therapeutic effects, selectively at the diseased tissues and target sites.

Optimization of Extraction or Purification Process of Multiple Components from Natural Products: Entropy Weight Method Combined with Plackett-Burman Design and Central Composite Design

In this paper, the optimization of the extraction/purification process of multiple components was performed by the entropy weight method (EWM) combined with Plackett-Burman design (PBD) and central composite design (CCD). We took the macroporous resin purification of Astragalus saponins as an example to discuss the practicability of this method. Firstly, the weight of each component was given by EWM and the sum of the product between the componential content and its weight was defined as the comprehensive score, which was taken as the evaluation index. Then, the single factor method was adopted for determining the value range of each factor. PBD was applied for screening the significant factors. Important variables were further optimized by CCD to determine the optimal process parameters. After the combination of EWM, PBD and CCD, the resulting optimal purification conditions were as follows: pH value of 6.0, the extraction solvent concentration of 0.15 g/mL, and the ethanol volume fraction of 75%. Under the optimal conditions, the practical comprehensive score of recoveries of saponins was close to the predicted value (n = 3). Therefore, the present study provided a convenient and efficient method for extraction and purification optimization technology of multiple components from natural products.

Increased Water-Solubility and Maintained Antioxidant Power of Resveratrol by Its Encapsulation in Vitamin E TPGS Micelles: A Potential Nutritional Supplement for Chronic Liver Disease

Children affected by chronic liver disease exhibit impaired neurocognitive development and growth due to the low absorption and digestion of nutrients. Furthermore, malnutrition is an adverse prognostic factor in liver transplantation as it is associated with an increase in morbidity and mortality. D-α-tocopheryl-polyethylene-glycol-succinate (TPGS) is currently administered per os as a vitamin E source to improve children's survival and well-being; however, TPGS alone does not reverse spinocerebellar degeneration and lipid peroxidation. To potentiate the effects of TPGS, we loaded micelles with resveratrol (RES), a natural polyphenol, with antioxidant and antiinflammatory activities, which has demonstrated protective action in the liver. Firstly, we investigated the suitability of TPGS to encapsulate RES in micelles by means of a phase-solubility study, then RES-TPGS formulations were prepared via solvent casting and solvent diffusion evaporation methods. RES-TPGS colloidal dispersions showed small mean diameters (12 nm), low polydispersity, and quite neutral Zeta potentials. The formulations showed a sustained drug release and a good drug loading capacity, further confirmed by infrared spectroscopy and differential scanning calorimetry. RES-TPGSs exhibited unaltered antioxidant activity compared to pristine RES via the DPPH assay and a significant reduction in toxicity compared to empty TPGS on HaCaT cells. Thus, RES-TPGS micelles may overcome the challenges of current liver disease therapy by providing more protective effects thanks to the antioxidant activity of RES and by reducing the surfactant toxicity on normal cells.

Quality by design (QbD)-based fabrication of atazanavir-loaded nanostructured lipid carriers for lymph targeting: bioavailability enhancement using chylomicron flow block model and toxicity studies

Atazanavir (ATV) is widely used as anti-HIV agent having poor aqueous solubility needs to modulate novel drug delivery system to enhance therapeutic efficiency and safety. The main objective of the present work was to fabricate ATV-loaded nanostructured lipid carriers (NLCs) employing quality by design (QbD) approach to address the challenges of bioavailability and their safety after oral administration. Herein, the main objective was to identify the influencing variables for the production of quality products. Considering this objective, quality target product profile (QTPP) was assigned and a systematic risk assessment study was performed to identify the critical material attributes (CMAs) and critical process parameter (CPP) having an influence on critical quality attributes (CQAs). Lipid concentrations, surfactant concentrations, and pressure of high-pressure homogenizer were identified as CMAs and CPP. ATV-NLCs were prepared by emulsification-high pressure homogenization method and further lyophilized to obtain solid-state NLCs. The effect of formulation variables (CMAs and CPP) on responses like particle size (Y₁), polydispersity index (Y₂), and zeta potential (Y₃) was observed by central composite rotatable design (CCRD). The data were statistically evaluated by ANOVA for confirmation of a significant level (p < 0.05). The optimal conditions of NLCs were obtained by generating design space and desirability value. The lyophilized ATV-NLCs were characterized by DSC, powder X-ray diffraction, and FT-IR analysis. The morphology of NLCs was revealed by TEM and FESEM. In vitro study suggested a sustained release pattern of drug (92.37 ± 1.03%) with a mechanism of Korsmeyer-Peppas model (r² = 0.925, and n = 0.63). In vivo evaluation in Wistar rats showed significantly higher (p < 0.001) plasma drug concentration of ATV-NLCs as compared to ATV-suspension using chylomicron flow block model. The relative bioavailability of ATV-NLCs was obtained to be 2.54 folds. Thus, a safe and promising drug targeting system was successfully developed to improve bioavailability and avoiding first-pass effect ensures to circumvent the acute-toxicity of liver.

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.

Encapsulation and Characterization of Nanoemulsions Based on an Anti-oxidative Polymeric Amphiphile for Topical Apigenin Delivery

Apigenin (Apig) is used as a model drug due to its many beneficial bio-activities and therapeutic potentials. Nevertheless, its poor water solubility and low storage stability have limited its application feasibility on the pharmaceutical field. To address this issue, this study developed nanoemulsions (NEs) using an anti-oxidative polymeric amphiphile, d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS), hydrogenated soy lecithin (HL), black soldier fly larvae (BSFL) oil, and avocado (AV) oil through pre-homogenization and ultrasonication method. Addition of TPGS (weight ratios 100 and 50% as compared to HL) into NEs effectively reduced particle size and phase transition region area of NEs with pure HL. Incorporation of Apig into NEs made particle size increase and provided a disorder effect on intraparticle molecular packing. Nevertheless, the encapsulation efficiency of NEs for Apig approached to about 99%. The chemical stability of Apig was significantly improved and its antioxidant ability was elevated by incorporation with BSFL oil and AV oil NEs, especially for NEs with single TPGS. NEs with single TPGS also exhibited the best Apig skin deposition. For future application of topical Apig delivery, NEs-gel was formed by the addition of hyaluronic acid (HA) into NEs. Their rheological characteristics were dominated by the surfactant ratios of HL to TPGS.

D-α-Tocopherol-Based Micelles for Successful Encapsulation of Retinoic Acid

All-trans-retinoic acid (ATRA) represents the first-choice treatment for several skin diseases, including epithelial skin cancer and acne. However, ATRA's cutaneous side effects, like redness and peeling, and its high instability limit its efficacy. To address these drawbacks and to improve ATRA solubilization, we prepared ATRA-loaded micelles (ATRA-TPGSs), by its encapsulation in D-α-tocopheryl-polyethylene-glycol-succinate (TPGS). First, to explore the feasibility of the project, a solubility study based on the equilibrium method was performed; then, six ATRA-TPGS formulations were prepared by the solvent-casting method using different TPGS amounts. ATRA-TPGSs showed small sizes (11-20 nm), low polydispersity, slightly negative zeta potential, and proved good encapsulation efficiency, confirmed by a chemometric-assisted Fourier transform infrared spectroscopy (FTIR) investigation. ATRA-TPGS stability was also investigated to choose the most stable formulation. Using Carbopol^® 980 as gelling agent, ATRA-TPGS-loaded gels were obtained and analyzed for their rheological profiles. Ex vivo release studies from ATRA-TPGSs were performed by Franz cells, demonstrating a permeation after 24 h of 22 ± 4 µ cm^-2. ATRA-TPGSs showed enhanced cytotoxic effects on melanoma cells, suggesting that these formulations may represent a valid alternative to improve patient compliance and to achieve more efficacious therapeutic outcomes.

The Efficacy of Cholesterol-Based Carriers in Drug Delivery

Several researchers have reported the use of cholesterol-based carriers in drug delivery. The presence of cholesterol in cell membranes and its wide distribution in the body has led to it being used in preparing carriers for the delivery of a variety of therapeutic agents such as anticancer, antimalarials and antivirals. These cholesterol-based carriers were designed as micelles, nanoparticles, copolymers, liposomes, etc. and their routes of administration include oral, intravenous and transdermal. The biocompatibility, good bioavailability and biological activity of cholesterol-based carriers make them potent prodrugs. Several in vitro and in vivo studies revealed cholesterol-based carriers potentials in delivering bioactive agents. In this manuscript, a critical review of the efficacy of cholesterol-based carriers is reported.