The use of TPGS in drug delivery systems to overcome biological barriers

Liposomal Tubacin: Strategies for the Formulation of a Highly Hydrophobic Anticancer Drug

Background: Clear-cell renal cell carcinoma (ccRCC) is the most prevalent form of kidney cancer, accounting for over 75% of cases worldwide. Histone deacetylase inhibitors (HDACIs) have emerged as promising agents for ccRCC treatment, particularly in combination with immunotherapy or targeted therapies. Tubacin, a potent HDAC6 inhibitor, has demonstrated potent anticancer activity but faces therapeutic limitations due to its hydrophobic nature and poor solubility, which hinder its effective drug delivery. This study explores liposomal encapsulation as a strategy to improve tubacin delivery; Methods: Liposomes were prepared using the ethanol injection method followed by size-exclusion chromatography. Using the Plackett-Burman Design, we identified a promising liposomal formulation and evaluated its biological activity in vitro; Results: However, initial formulations reduced the mitochondrial activity to 30% in healthy renal cell lines. To mitigate this, we optimized the formulation by reducing tocopheryl polyethylene glycol succinate (TPGS) content and incorporating Kolliphor® as an additional surfactant. This optimized formulation significantly reduced toxicity in noncancerous cells, with up to 80% of mitochondrial activity conserved while retaining key properties for therapeutic application; Conclusions: Our findings demonstrate that liposomal encapsulation enhances the safety and delivery of hydrophobic drugs like tubacin. This approach offers a promising strategy for improving the efficacy of HDACIs in ccRCC treatment, potentially overcoming drug delivery challenges associated with hydrophobic molecules.

Vitamins as excipients in pharmaceutical products

Excipients are ingredients in pharmaceutical products other than the active ingredient, added to facilitate manufacturing, enhance stability or modulate release and bioavailability. Vitamins are diverse molecules essential for human nutrition that also can fulfil excipient functions. This review focuses on vitamins used as excipients and provides an overview of the functions of vitamins in various pharmaceutical formulations. A thorough search was conducted to understand the current use of vitamins in marketed drug products, concluding that many vitamins are already used as functional excipients. Vitamins are used widely in different dosage forms, including oral, parenteral, and topical formulations, and alongside a broad range of active pharmaceutical ingredients, biologics, and small molecules from different biopharmaceutical classification system classes. Many examples of the use of vitamins to improve the performance of the pharmaceutical formulation in which they are included are presented and the mode of action of vitamins as excipients in the product is reviewed. Furthermore, the potential for future uses of vitamins in pharmaceutical products is highlighted. Lastly, considerations for the use of vitamins as excipients in drug products as well as the regulatory framework are discussed.

Chitosan nanoparticles of imatinib mesylate coated with TPGS for the treatment of colon cancer: In-vivo & in-vitro studies

The study aimed to develop and evaluate chitosan-based nanoparticles coated with TPGS for the targeted delivery of imatinib mesylate to colon cancer cells. Particle size and zeta potential analysis were within the acceptable range for targeting colon cancer. CS-IMT-TPGS-NPs had a significant positive zeta potential of 30.4 mV, suggesting improved cellular intake. FE-SEM and TEM demonstrated that the nanoparticles appeared spherical, smooth, and did not aggregate, with a visible TPGS coating. XRD confirmed that crystalline imatinib transitioned to an amorphous state during nano formulation. In-vitro tests on HCT-116 cells demonstrated that CS-IMT-TPGS-NPs outperformed free IMT regarding cytotoxicity, apoptosis induction, cellular uptake, and cell migration inhibition. Additionally, the nanoparticles were examined in vitro using mitochondrial membrane potential, DNA fragmentation, GAPDH relative gene expression, ROS estimation, and cell cycle analysis. The effect of therapy on expected colon-associated bacterial strains was also investigated. The biocompatibility of nanoparticles was assessed by hemolysis and platelet aggregation experiments. The anti-inflammatory impact was determined using the HET-CAM test. Non-Fickian diffusion at pH 5.5 resulted in sustained in-vitro drug release, with no initial burst. In-vivo investigations using albino Wistar rats suggest pharmacokinetic properties for produced nanoparticles, whereas histopathological examinations assess acute toxicity.

Formulation Study of a Poly(amino methacrylate) Film-Forming Solution for Transdermal Administration

BACKGROUND/OBJECTIVES

The objective of this paper is to design a novel film-forming system (FFS) based on Eudragit® E PO (EuE) polymeric solutions, differing in volatile solvents (i.e., isopropanol and ethanol) and plasticizers (i.e., tributylcitrate, glycerine, triacetin and PEG 400).

METHODS

The physicochemical and mechanical properties of the FFS and dried films were evaluated in terms of formation time, stickiness, Tg, tensile strength, break elongation and Young's modulus. The in vitro skin permeation studies were conducted on formulations containing caffeine and testosterone.

RESULTS

The FFS, consisting of EuE and PEG400 in isopropyl alcohol and ethanol (80:20, v/v), exhibited rapid film formation within about 5 min and the dried film allowed a high skin permeability compared to other formulations due to the ability to increase the thermodynamic activity of both drugs. When triiodothyronine (T3) was loaded as a model of a very low soluble drug, tocopherol polyethylene glycol succinate (TPGS) was added as a co-solvent and it allowed for the improvement of T3 retention in the skin.

CONCLUSIONS

Among the formulative variables, the nature and the amount of plasticizer represent the most critical variables to obtain an EuE-based film with satisfying physical and biopharmaceutical properties.

Polymeric Nanoparticles Potentiate the Anticancer Activity of Novel PI3Kα Inhibitors Against Triple-Negative Breast Cancer Cells

Background: Dysregulation in phosphoinositide-3-kinase alpha (PI3Kα) signaling is implicated in the development of various cancers, including triple-negative breast cancer (TNBC). We have previously synthesized a series of N-phenyl-6-chloro-4-hydroxy-2-quinolone-3-carboxamides as targeted inhibitors against PI3Kα. Herein, two drug candidates, R7 and R11, were selected to be further investigated as a nanoparticle (NP) formulation against TNBC. Methods: R7 and R11 were entrapped in D-α-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS) polymeric NPs by nanoprecipitation. Following their physicochemical characterization, the anticancer activity of the compounds and their NP formulations was evaluated in the TNBC cell line MDA-MB-231 by conducting viability, uptake, and apoptosis assays, as well as penetration assays in a multicellular tumor spheroid model. Results: The NPs exhibited a particle size of 100-200 nm, excellent drug loading efficiencies, and sustained release under physiologic conditions. Viability assays revealed superior potency for the NP formulations, with IC50 values of 20 µM and 30 µM for R7- and R11-loaded NPs, respectively, compared to the free compounds, which exhibited IC50 values of 280 µM and 290 µM for R7 and R11, respectively. These results were attributed to the inherent antiproliferative activity of TPGS, as evidenced by the cytotoxicity of the drug-free NPs, as well as the enhanced cellular uptake enabled by the NP vehicle, as demonstrated by fluorescence microscopy imaging and flow cytometry measurements. Further investigations showed that the NPs promoted apoptosis via a mitochondrial-dependent pathway that involved the activation of proapoptotic caspases. Moreover, the NP formulations enhanced the penetration ability of the free compounds in multicellular tumor spheroids, causing a time- and concentration-dependent disruption of the spheroids. Conclusions: Our findings highlight the important role nanotechnology can play in improving the biopharmaceutical properties of new drug candidates and facilitating their in vivo translation.

Recent Developments in Luteolin-Loaded Nanoformulations for Enhanced Anti-Carcinogenic Activities: Insights from In Vitro and In Vivo Studies

With approximately 18 million people affected by cancer in 2020 globally, scientists are exploring innovative approaches to develop effective treatments for various types of cancer. Traditional chemotherapy drugs, although effective against cancer cells, often lead to significant side effects on healthy tissues, such as hair loss, anemia, and nausea. To discover safer alternatives, researchers are investigating natural bioactive compounds found abundantly in plants. Luteolin, a flavonoid found in celery and artichokes, stands out due to its diverse anti-carcinogenic properties, including inhibiting proliferation, inducing apoptosis, activating autophagy, and inhibiting angiogenesis and metastasis. However, the therapeutic potential of luteolin is hindered by challenges related to its bioavailability and solubility. This critical review explores the specific anti-carcinogenic properties of luteolin while analyzing the impact of its limited bioavailability and solubility on effectiveness. Additionally, it investigates the outcomes of encapsulating luteolin in nanoformulations, providing insights into potential strategies for enhancing its anti-carcinogenic effects. Finally, the review compares the efficacy of luteolin with and without nanoformulations. This review provides valuable insights into the potential of utilizing luteolin-loaded nanoformulations as a safer and more effective method for treating cancer, contributing to the ongoing efforts in improving cancer care and outcomes worldwide.

Drug Nanocrystals in Oral Absorption: Factors That Influence Pharmacokinetics

Despite the safety and convenience of oral administration, poorly water-soluble drugs compromise absorption and bioavailability. These drugs can exhibit low dissolution rates, variability between fed and fasted states, difficulty permeating the mucus layer, and P-glycoprotein efflux. Drug nanocrystals offer a promising strategy to address these challenges. This review focuses on the opportunities to develop orally administered nanocrystals based on pharmacokinetic outcomes. The impacts of the drug particle size, morphology, dissolution rate, crystalline state on oral bioavailability are discussed. The potential of the improved dissolution rate to eliminate food effects during absorption is also addressed. This review also explores whether permeation or dissolution drives nanocrystal absorption. Additionally, it addresses the functional roles of stabilizers. Drug nanocrystals may result in prolonged concentrations in the bloodstream in some cases. Therefore, nanocrystals represent a promising strategy to overcome the challenges of poorly water-soluble drugs, thus encouraging further investigation into unclear mechanisms during oral administration.

Comparative Study of TPGS and Soluplus Polymeric Micelles Embedded in Poloxamer 407 In Situ Gels for Intranasal Administration

This study aims to highlight the importance of choosing the appropriate co-polymer or co-polymer mixed combinations in order to design value-added nasal dosage forms. Local therapy of upper respiratory tract-related infections, such as nasal rhinosinusitis is of paramount importance, thus advanced local therapeutic options are required. Dexamethasone was encapsulated into three different polymeric micelle formulations: Soluplus or TPGS-only and their mixed combinations. Dynamic light scattering measurements proved that the particles have a micelle size less than 100 nm in monodisperse distribution, with high encapsulation efficiency above 80% and an at least 7-fold water solubility increase. Tobramycin, as an antimicrobial agent, was co-formulated into the in situ gelling systems which were optimized based on gelation time and gelation temperature. The sol-gel transition takes place between 32-35 °C, which is optimally below the temperature of the nasal cavity in a quick manner below 5 min, a suitable strategic criterion against the mucociliary clearance. In vitro drug release and permeability studies confirmed a rapid kinetics in the case of the encapsulated dexamethasone accompanied with a sustained release of tobramycin, as the hydrophilic drug.

Polycaprolactone-Vitamin E TPGS Micellar Formulation for Oral Delivery of Paclitaxel

This study aimed to investigate the potential of polycaprolactone-vitamin E TPGS (PCL-TPGS) micelles as a delivery system for oral administration of paclitaxel (PTX). The PCL-TPGS copolymer was synthesized using ring opening polymerization, and PTX-loaded PCL-TPGS micelles (PTX micelles) were prepared via a co-solvent evaporation method. Characterization of these micelles included measurements of size, polydispersity, and encapsulation efficiency. The cellular uptake of PTX micelles was evaluated in Caco-2 cells using rhodamine 123 (Rh123) as a fluorescent probe. Moreover, an everted rat sac study was conducted to evaluate the ex vivo permeability of PTX micelles. Additionally, a comparative pharmacokinetic study of PTX micelles versus the marketed formulation, Ebetaxel® (a Taxol generic), was performed after a single oral administration to rats. The results demonstrated that the micellar formulation significantly improved PTX solubility (nearly 1 mg/mL). The in vitro stability and release of PTX micelles in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) demonstrated that PTX micelles remained stable for up to 24 h and significantly slowed the release of PTX in both media compared to Ebetaxel®. The in vitro cellular uptake, ex vivo intestinal permeability, and in vivo pharmacokinetic profile demonstrated that PTX micelles enhanced the permeability and facilitated a rapid absorption of the drug. Conclusively, the PCL7000-TPGS3500 micelles exhibit potential as an effective oral delivery system for PTX.

Formulation and Evaluation of Meloxicam Hybrid nano Particles

The goal of the present study was to prepare meloxicam (MX) entrapped hybrid particles (HPs) to enhance intestinal permeation and anti-inflammatory activity. MX-HPs were prepared by nanoprecipitation method using lipid, chitosan, poloxamer, and TPGS. The formulations (MX-HPs1, MX-HPs2, MX-HPs3) were evaluated for particle size, entrapment efficiency, and drug release to select the optimized composition and further evaluated for permeation study, stability study, morphology, interaction study, and anti-inflammatory activity by carrageenan-induced rat paw edema test. The prepared MX-HPs showed nano sized particles (198.5 ± 3.7 to 223.8 ± 2.1 nm) and PDI (<0.3), zeta potential (16.5 ± 2.7 to 29.1 ± 3.6 mV), and high entrapment efficiency (75.1 ± 4.7 to 88.5 ± 3.9%). The surface morphology was assessed by transmission electron microscopy and showed non-aggregated particles. Infra-red (IR) spectroscopy of pure MX as well as formulation revealed no drug-polymer interaction and X-ray diffraction confirmed the conversion of crystalline MX into amorphous form. The release study data revealed prolonged MX release for 24 h. The selected optimized hybrid particles (MX-HPs2) revealed a 2.3-fold improved enhancement ratio than free MX. The storage stability and gastrointestinal stability data demonstrated a stable formulation in SIF as well as SGF. The anti-inflammatory activity showed better therapeutic action than pure MX dispersion. From the study, it can be concluded that the prepared MX-HPs may be a promising delivery system for MX in treating inflammatory disorders.

AS1411 aptamer/RGD dual functionalized theranostic chitosan-PLGA nanoparticles for brain cancer treatment and imaging

Conventional chemotherapy and poor targeted delivery in brain cancer resulting to poor treatment and develop resistance to anticancer drugs. Meanwhile, it is quite challenging to diagnose/detection of brain tumor at early stage of cancer which resulting in severity of the disease. Despite extensive research, effective treatment with real-time imaging still remains completely unavailable, yet. In this study, two brain cancer cell specific moieties i.e., AS1411 aptamer and RGD are decorated on the surface of chitosan-PLGA nanoparticles to improve targeted co-delivery of docetaxel (DTX) and upconversion nanoparticles (UCNP) for effective brain tumor therapy and real-time imaging. The nanoparticles were developed by a slightly modified emulsion/solvent evaporation method. This investigation also translates the successful synthesis of TPGS-chitosan, TPGS-RGD and TPGS-AS1411 aptamer conjugates for making PLGA nanoparticle as a potential tool of the targeted co-delivery of DTX and UCNP to the brain cancer cells. The developed nanoparticles have shown an average particle size <200 nm, spherical in shape, high encapsulation of DTX and UCNP in the core of nanoparticles, and sustained release of DTX up to 72 h in phosphate buffer saline (pH 7.4). AS1411 aptamer and RGD functionalized theranostic chitosan-PLGA nanoparticles containing DTX and UCNP (DUCPN-RGD-AS1411) have achieved greater cellular uptake, 89-fold improved cytotoxicity, enhanced cancer cell arrest even at lower drug conc., improved bioavailability with higher mean residence time of DTX in systemic circulation and brain tissues. Moreover, DUCPN-RGD-AS1411 have greatly facilitated cellular internalization and higher accumulation of UCNP in brain tissues. Additionally, DUCPN-RGD-AS1411 demonstrated a significant suppression in tumor growth in brain-tumor bearing xenograft BALB/c nude mice with no impressive sign of toxicities. DUCPN-RGD-AS1411 has great potential to be utilized as an effective and safe theranostic tool for brain cancer and other life-threatening cancer therapies.

Polycaprolactone - Vitamin E TPGS micelles for delivery of paclitaxel: In vitro and in vivo evaluation

This study aimed to present findings on a paclitaxel (PTX)-loaded polymeric micellar formulation based on polycaprolactone-vitamin E TPGS (PCL-TPGS) and evaluate its in vitro anticancer activity as well as its in vivo pharmacokinetic profile in healthy mice in comparison to a marketed formulation. Micelles were prepared by a co-solvent evaporation method. The micelle's average diameter and polydispersity were determined using dynamic light scattering (DLS) technique. Drug encapsulation efficiency was assessed using an HPLC assay. The in vitro cytotoxicity was performed on human breast cancer cells (MCF-7 and MDA-MB-231) using MTT assay. The in vivo pharmacokinetic profile was characterized following a single intravenous dose of 4 mg/kg to healthy mice. The mean diameters of the prepared micelles were ≤ 100 nm. Moreover, these micelles increased the aqueous solubility of PTX from ∼0.3 μg/mL to reach nearly 1 mg/mL. While the PTX-loaded micelles showed an in vitro cytotoxicity comparable to the marketed formulation (Ebetaxel), drug-free PCL-TPGS micelles did not show any cytotoxic effects on both types of breast cancer cells (∼100% viability). Pharmacokinetics of PTX as part of PCL-TPGS showed a significant increase in its volume of distribution compared to PTX conventional formulation, Ebetaxel, which is in line with what was reported for clinical nano formulations of PTX, i.e., Abraxane, Genexol-PM, or Apealea. The findings of our studies indicate a significant potential for PCL-TPGS micelles to act as an effective system for solubilization and delivery of PTX.

Novel Drug Delivery Approaches for the Localized Treatment of Cervical Cancer

Cervical cancer (CC) is the fourth leading cancer type in females globally. Being an ailment of the birth canal, primitive treatment strategies, including surgery, radiation, or laser therapy, bring along the risk of infertility, neonate mortality, premature parturition, etc. Systemic chemotherapy led to systemic toxicity. Therefore, delivering a smaller cargo of therapeutics to the local site is more beneficial in terms of efficacy as well as safety. Due to the regeneration of cervicovaginal mucus, conventional dosage forms come with the limitations of leaking, the requirement of repeated administration, and compromised vaginal retention. Therefore, these days novel strategies are being investigated with the ability to combat the limitations of conventional formulations. Novel carriers can be engineered to manipulate bioadhesive properties and sustained release patterns can be obtained thus leading to the maintenance of actives at therapeutic level locally for a longer period. Other than the purpose of CC treatment, these delivery systems also have been designed as postoperative care where a certain dose of antitumor agent will be maintained in the cervix postsurgical removal of the tumor. Herein, the most explored localized delivery systems for the treatment of CC, namely, nanofibers, nanoparticles, in situ gel, liposome, and hydrogel, have been discussed in detail. These carriers have exceptional properties that have been further modified with the aid of a wide range of polymers in order to serve the required purpose of therapeutic effect, safety, and stability. Further, the safety of these delivery systems toward vital organs has also been discussed.

Bottom-up production of injectable itraconazole suspensions using membrane technology

Bottom-up production of active pharmaceutical ingredient (API) crystal suspensions offers advantages in surface property control and operational ease over top-down methods. However, downstream separation and concentration pose challenges. This proof-of-concept study explores membrane diafiltration as a comprehensive solution for downstream processing of API crystal suspensions produced via anti-solvent crystallization. It involves switching the residual solvent (N-methyl-2-pyrrolidone, NMP) with water, adjusting the excipient (d-α-Tocopherol polyethylene glycol 1000 succinate, TPGS) quantity, and enhancing API loading (solid concentration) in itraconazole crystal suspensions. NMP concentration was decreased from 9 wt% to below 0.05 wt% (in compliance with European Medicine Agency guidelines), while the TPGS concentration was decreased from 0.475 wt% to 0.07 wt%. This reduced the TPGS-to-itraconazole ratio from 1:2 to less than 1:50 and raised the itraconazole loading from 1 wt% to 35.6 wt%. Importantly, these changes did not adversely affect the itraconazole crystal stability in suspension. This study presents membrane diafiltration as a one-step solution to address downstream challenges in bottom-up API crystal suspension production. These findings contribute to optimizing pharmaceutical manufacturing processes and hold promise for advancing the development of long-acting API crystal suspensions via bottom-up production techniques at a commercial scale.

Atorvastatin-loaded cubosome: a repurposed targeted delivery systems for enhanced targeting against breast cancer

Cancer ranks as one of the most challenging illnesses to deal with because progressive phenotypic and genotypic alterations in cancer cells result in resistance and recurrence. Thus, the creation of novel medications or alternative therapy approaches is mandatory. Repurposing of old drugs is an attractive approach over the traditional drug discovery process in terms of shorter drug development duration, low-cost, highly efficient and minimum risk of failure. In this study Atorvastatin, a statin drug used to treat abnormal cholesterol levels and prevent cardiovascular disease in people at high risk, was introduced and encapsulated in cubic liquid crystals as anticancer candidate aiming at sustaining its release and achieving better cellular uptake in cancer cells. The cubic liquid crystals were successfully prepared and optimized with an entrapment effieciency of 73.57% ±1.35 and particle size around 200 nm. The selected formulae were effectively doped with radioactive iodine 131I to enable the noninvasive visualization and trafficking of the new formulae. The in vivo evaluation in solid tumor bearing mice was conducted for comparing131I-Atorvastatin solution,131I-Atorvastatin loaded cubosome and 131I-Atorvastatin chitosan coated cubosome. The in vivo biodistribution study revealed that tumor radioactivity uptake of 131I-Atorvastatin cubosome and chitosan coated cubosome exhibited high accumulation in tumor tissues (target organ) scoring ID%/g of 5.67 ± 0.2 and 5.03 ± 0.1, respectively 1h post injection compared to drug solution which recorded 3.09 ± 0.05% 1h post injection. Concerning the targeting efficiency, the target/non target ratio for 131I-Atorvastatin chitosan coated cubosome was higher than that of 131I-Atorvastatin solution and 131I ATV-loaded cubosome at all time intervals and recorded T/NT ratio of 2.908 2h post injection.

Novel PEGylated cholephytosomes for targeting fisetin to breast cancer: in vitro appraisal and in vivo antitumoral studies

Fisetin (FIS) is a multifunctional bioactive flavanol that has been recently exploited as anticancer drug against various cancers including breast cancer. However, its poor aqueous solubility has constrained its clinical application. In the current work, fisetin is complexed for the first time with soy phosphatidylcholine in the presence of cholesterol to form a novel biocompatible phytosomal system entitled "cholephytosomes." To improve fisetin antitumor activity against breast cancer, stearylamine bearing cationic cholephytosomes (mPHY) were prepared and furtherly modified with hyaluronic acid (HPHY) to allow their orientation to cancer cells through their surface exposed phosphatidylserine and CD-44 receptors, respectively. In vitro characterization studies revealed promising physicochemical properties of both modified vesicles (mPHY and HPHY) including excellent FIS complexation efficiency (˷100%), improved octanol/water solubility along with a sustained drug release over 24 h. In vitro cell line studies against MDA-MB-231 cell line showed about 10- and 3.5-fold inhibition in IC50 of modified vesicles compared with free drug and conventional drug-phospholipid complex, respectively. Preclinical studies revealed that both modified cholephytosomes (mPHY and HPHY) had comparable cytotoxicity that is significantly surpassing free drug cytotoxicity. TGF-β1and its non-canonical related signaling pathway; ERK1/2, NF-κB, and MMP-9 were involved in halting tumorigenesis. Thus, tailoring novel phytosomal nanosystems for FIS could open opportunity for its clinical utility against cancer.

Fabrication of TPGS decorated Etravirine loaded lipidic nanocarriers as a neoteric oral bioavailability enhancer for lymphatic targeting

Etravirine (ERVN) is a potential NNRTI (non-nucleoside reverse transcriptase inhibitor) in treating HIV infection. It possesses extremely low oral bioavailability. The present research aims to optimize the formulation and characterization of TPGS-enriched ERVN-loaded lipid-based nanocarriers (NLCs) for HIV-infected patients. The formulation, ERVN-TPGS-NLCs, was optimized by central composite rotational design using a modified-solvent emulsification process. Various characterization parameters of NLCs were evaluated, including globule size of 121.56 ± 2.174 nm, PDI of 0.172 ± 0.042, the zeta potential of - 7.32 ± 0.021 mV, %EE of 94.42 ± 8.65% of ERVN and %DL was 8.94 ± 0.759% of ERVN and spherical shape was revealed by TEM. PXRD was also performed to identify the crystallinity of the sample. In-vitro drug release showed % a cumulative drug release of 83.72 ± 8.35% at pH 1.2 and 90.61 ± 9.11% at pH 6.8, respectively, whereas the % cumulative drug release from drug suspension (ERVN-S) was found to be 21.13 ± 2.01% at pH 1.2 and 24.84 ± 2.51 at pH 6.8 at the end of 48 h. Further, the intestinal permeation study and confocal microscope showed approximately three-fold and  two-fold increased permeation in ERVN-TPGS-NLCs and ERVN-NLCs across the gut sac compared to ERVN-S. Hemolysis compatibility and lipolysis studies were performed to predict the in-vivo fate of the formulation. The pharmacokinetic study revealed a 3.13-fold increment in the relative bioavailability, which agrees with the ex-vivo studies, and lymphatic uptake was validated by using cycloheximide along with designed formulation, which showed the impact of lymphatic uptake in AUC. This study ensures that ERVN-TPGS-NLCs take lymphatic uptake to minimize the first-pass metabolism followed by improved oral bioavailability of ERVN. Thus, the enhanced bioavailability of ERVN can reduce the high dose of ERVN to minimize the adverse effects related to dose-related burden.

The Chimera of TPGS and Nanoscale Lipid Carriers as Lymphatic Drug Delivery Vehicles to Fight Metastatic Cancers

The lymphatic system (LS) plays a crucial role in fluid balance, transportation of macromolecules, and immune response. Moreover, LS is a channel for microbial invasion and cancer metastasis. Particularly, solid tumors, including lung, breast, melanoma, and prostate cancers, are metastasized across highways of LS. Subsequently, the fabrication of chimeric lymphatic drug delivery systems (LDDS) is a promising strategy to fight cancer metastasis and control microbial pandemics. In this regard, LDDS, in terms of PEG-nanoscaled lipid carriers, elicited a revolution during the COVID-19 pandemic as cargoes for mRNA vaccines. The drug delivered by the lymphatic pathway escapes first-pass metabolism and enhances the drug's bioavailability. Ample approaches, including synthesis of prodrugs, trigging of chylomicron biosynthesis, and fabrication of nanocarriers, facilitate lymphatic drug delivery. Specifically, nanoscales lipid cargoes have the propensity to lymphatic trafficking. Interestingly, TPGSengineered nanoscale lipid cargoes enhance lymphatic trafficking, increase tissue permeation, and, specifically, uptake. Moreover, they overcome biological barriers, control biodistribution, and enhance organelles localization. Most anticancer agents are non-specific, have low bioavailability, and induced drug resistance. Therefore, TPGS-engineered nanoscale lipid chimeras improve the therapeutic impact of anticancer agents. This review highlights lymphatic cancer metastasis, nanoscales lipid cargoes as LDDS, and their influence on lymphatic trafficking, besides the methods of LDD studies.

Development of long-acting injectable suspensions by continuous antisolvent crystallization: An integrated bottom-up process

Our present work elucidated the operational feasibility of direct generation and stabilization of long-acting injectable (LAI) suspensions of a practically insoluble drug, itraconazole (ITZ), by combining continuous liquid antisolvent crystallization with downstream processing (i.e., centrifugal filtration and reconstitution). A novel microchannel reactor-based bottom-up crystallization setup was assembled and optimized for the continuous production of micro-suspension. Based upon the solvent screening and solubility study, N-methyl pyrrolidone (NMP) was selected as the optimal solvent and an impinging jet Y-shaped microchannel reactor (MCR) was selected as the fluidic device to provide a reproducible homogenous mixing environment. Operating parameters such as solvent to antisolvent ratio (S/AS), total jet liquid flow rates (TFRs), ITZ feed solution concentration and the maturation time in spiral tubing were tailored to 1:9 v/v, 50 mL/min, 10 g/100 g solution, and 96 h, respectively. Vitamin E TPGS (0.5% w/w) was found to be the most suitable excipient to stabilize ITZ particles amongst 14 commonly used stabilizers screened. The effect of scaling up from 25 mL to 15 L was evaluated effectively with in situ monitoring of particle size distribution (PSD) and solid-state form. Thereafter, the suspension was subjected to centrifugal filtration to remove excess solvent and increase ITZ solid fraction. As an alternative, an even more concentrated wet pellet was reconstituted with an aqueous solution of 0.5% w/w Vitamin E TPGS as resuspending agent. The ITZ LAI suspension (of 300 mg/mL solid concentration) has the optimal PSD with a D10 of 1.1 ± 0.3 µm, a D50 of 3.53 ± 0.4 µm and a D90 of 6.5 ± 0.8 µm, corroborated by scanning electron microscopy (SEM), as remained stable after 548 days of storage at 25 °C. Finally, in vitro release methods using Dialyzer, dialysis membrane sac were investigated for evaluation of dissolution of ITZ LAI suspensions. The framework presented in this manuscript provides a useful guidance for development of LAI suspensions by an integrated bottom-up approach using ITZ as model API.

Encapsulation of Olive Leaf Polyphenol-Rich Extract in Polymeric Micelles to Improve Its Intestinal Permeability

In the present study, polymeric micelles were developed to improve the intestinal permeability of an extract of Olea europaea L. leaf with a high content of total polyphenols (49% w/w), with 41% w/w corresponding to the oleuropein amount. A pre-formulation study was conducted to obtain a stable formulation with a high loading capacity for extract. The freeze-drying process was considered to improve the stability of the formulation during storage. Micelles were characterized in terms of physical and chemical properties, encapsulation efficiency, stability, and in vitro release. The optimized system consisted of 15 mg/mL of extract, 20 mg/mL of Pluronic L121, 20 mg/mL of Pluronic F68, and 10 mg/mL of D-α-tocopheryl polyethylene glycol succinate (TPGS), with dimensions of 14.21 ± 0.14 nm, a polydisersity index (PdI) of 0.19 ± 0.05 and an encapsulation efficiency of 66.21 ± 1.11%. The influence of the micelles on polyphenol permeability was evaluated using both Parallel Artificial Membrane Permeability Assay (PAMPA) and the Caco-2 cell monolayer. In both assays, the polymeric micelles improved the permeation of polyphenols, as demonstrated by the increase in Pe and Papp values.

Design, Development, and Evaluation of SA-F127:TPGS Polymeric Mixed Micelles for Improved Delivery of Glipizide Drug: In-vitro, Ex-vivo, and In-vivo Investigations

The anti-diabetic glipizide (GLN) drug has notable pharmaceutical advantages, but poor aqueous solubility restricts its wide applications. The present work was to develop a mixed polymeric micelle system composed of SA-F127 and TPGS to improve the water solubility and effective delivery of the GLN. First, we synthesized SA-F127 and confirmed it through FTIR, NMR, and GPC techniques. The GLN-PMM were fabricated with the thin-film technique and optimized with CCD design. The developed GLN-PMM was characterized using DLS, Zeta, TEM, Rheology, FTIR, DSC, and XRD measurements. The GLN-PMM manifested a spherical morphology with 67.86 nm particle size, a -3.85 mV zeta potential, and a 0.582±0.06 PDI value. The polymeric mixed micelles showed excellent compatibility with GLN and were amorphous in nature. NMR studies confirmed the encapsulation of GLN in the core of the mixed micelle. In addition, the GLN-PMM micelles were tested in vitro for cumulative drug release, ex vivo for permeation, and in vivo for anti-diabetic investigations. The GLN-PMM release profile in the various pH environments showed over 90% after 24 h, clearly indicating sustained release. The GLN-PMM micelles gave higher 88.86±3.39% GLN permeation from the goat intestine compared with free GLN. In-vivo anti-diabetic investigation proves the powerful anti-diabetic properties of GLN-PMM in comparison to the marketed formulation. These findings demonstrated that the polymeric mixed micelles of SA-F127 and TPGS could be a promising, effective, and environment-friendly approach for oral delivery of the GLN.

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.

Mesoporous Polydopamine-Encapsulated Fluorescent Nanodiamonds: A Versatile Platform for Biomedical Applications

Fluorescent nanodiamonds (FNDs) are versatile nanomaterials with promising properties. However, efficient functionalization of FNDs for biomedical applications remains challenging. In this study, we demonstrate mesoporous polydopamine (mPDA) encapsulation of FNDs. The mPDA shell is generated by sequential formation of micelles via self-assembly of Pluronic F127 (F127) with 1,3,5-trimethyl benzene (TMB) and composite micelles via oxidation and self-polymerization of dopamine hydrochloride (DA). The surface of the mPDA shell can be readily functionalized with thiol-terminated methoxy polyethylene glycol (mPEG-SH), hyperbranched polyglycerol (HPG), and d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS). The PEGylated FND@mPDA particles are efficiently taken up by, and employed as a fluorescent imaging probe for, HeLa cells. HPG-functionalized FND@mPDA is conjugated with an amino-terminated oligonucleotide to detect microRNA via hybridization. Finally, the increased surface area of the mPDA shell permits efficient loading of doxorubicin hydrochloride. Further modification with TPGS increases drug delivery efficiency, resulting in high toxicity to cancer cells.

Non-Antibiotic Compounds Synergistically Kill Chronic Wound-Associated Bacteria and Disrupt Their Biofilms

Chronic wounds and their treatment present a significant burden to patients and healthcare systems alike, with their management further complicated by bacterial infection. Historically, antibiotics have been deployed to prevent and treat infections, but the emergence of bacterial antimicrobial resistance and the frequent development of biofilms within the wound area necessitates the identification of novel treatment strategies for use within infected chronic wounds. Here, several non-antibiotic compounds, polyhexamethylene biguanide (PHMB), curcumin, retinol, polysorbate 40, ethanol, and D-α-tocopheryl polyethylene glycol succinate 1000 (TPGS) were screened for their antibacterial and antibiofilm capabilities. The minimum inhibitory concentration (MIC) and crystal violet (CV) biofilm clearance against two bacteria frequently associated with infected chronic wounds, Staphylococcus aureus and Pseudomonas aeruginosa, were determined. PHMB was observed to have highly effective antibacterial activity against both bacteria, but its ability to disperse biofilms at MIC levels was variable. Meanwhile, TPGS had limited inhibitory activity but demonstrated potent antibiofilm properties. The subsequent combination of these two compounds in a formulation resulted in a synergistic enhancement of their capability to kill both S. aureus and P. aeruginosa and disperse their biofilms. Collectively, this work highlights the utility of combinatory approaches to the treatment of infected chronic wounds where bacterial colonization and biofilm formation remains significant issues.

Size-optimized simvastatin-loaded TPGS modified lipid nanocapsules for targeting epithelial-to-mesenchymal transition in hepatocellular carcinoma: Role of PTEN/AKT signaling

OBJECTIVES

Novel D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) modified lipid nanocapsules (LNC) were prepared with the aim of improving the effectiveness of simvastatin (SIM) in hepatocellular carcinoma (HCC). The present study, therefore, sought to investigate the effect of size-optimized SIM-loaded LNC on epithelial-to-mesenchymal transition (EMT) in HCC, providing insights on the implication of phosphatase and tensin homolog (PTEN)/protein kinase B (AKT) axis.

METHODS

Two optimized SIM-loaded LNCs with particle sizes 25 nm (SIM-LNC25) and 50 nm (SIM-LNC50) were prepared and biodistribution studies were performed. The anticancer effect of the prepared LNC was evaluated both in vitro and in vivo. The anti-migratory potential and EMT suppression through PTEN/AKT axis modulation were also explored.

RESULTS

SIM-LNC50 was superior to SIM-LNC25 in both in vitro and in vivo experiments, as evidenced by cytotoxicity assays, tumor histopathology, and enhanced apoptosis. SIM-LNC50 also alleviated the migratory potential of HCC cells. Moreover, EMT markers implied a transition of tumor cells toward the epithelial rather than the mesenchymal phenotype both in vitro and in vivo. PTEN/AKT axis modulation was also evident with SIM-LNC50.

CONCLUSION

The present study, therefore, suggests the efficacy of the 50 nm particles in SIM-loaded LNC in HCC by targeting EMT via modulating the PTEN/AKT signaling axis.

Breaking Barriers in Eye Treatment: Polymeric Nano-Based Drug-Delivery System for Anterior Segment Diseases and Glaucoma

The eye has anatomical structures that function as robust static and dynamic barriers, limiting the penetration, residence time, and bioavailability of medications administered topically. The development of polymeric nano-based drug-delivery systems (DDS) could be the solution to these challenges: it can pass through ocular barriers, offering higher bioavailability of administered drugs to targeted tissues that are otherwise inaccessible; it can stay in ocular tissues for longer periods of time, requiring fewer drug administrations; and it can be made up of polymers that are biodegradable and nano-sized, minimizing the undesirable effects of the administered molecules. Therefore, therapeutic innovations in polymeric nano-based DDS have been widely explored for ophthalmic drug-delivery applications. In this review, we will give a comprehensive overview of polymeric nano-based drug-delivery systems (DDS) used in the treatment of ocular diseases. We will then examine the current therapeutic challenges of various ocular diseases and analyze how different types of biopolymers can potentially enhance our therapeutic options. A literature review of the preclinical and clinical studies published between 2017 and 2022 was conducted. Thanks to the advances in polymer science, the ocular DDS has rapidly evolved, showing great promise to help clinicians better manage patients.

Natural Products-based Drugs: Potential Drug Targets Against Neurological Degeneration

Phytochemicals or natural products have been studied extensively for their potential in the treatment of neurodegenerative diseases (NDs) like Parkinson's disease, Alzheimer's disease, etc. The neuronal structure loss and progressive dysfunction are the main characteristics of these diseases. In spite of impressive and thorough knowledge of neurodegenerative molecular pathways, little advancement has been found in the treatment of the same. Moreover, it was proved that natural products can be used efficiently in the treatment of NDs while certain issues regarding the patient's safety and clinical data are still existing. As ND is a bunch of diseases and it will start the myriad of pathological processes, active targeting of the molecular pathway behind ND will be the most efficient strategy to treat all ND-related diseases. The targeting pathway must prevent cell death and should restore the damaged neurons. In the treatment of ND and related diseases, natural products are playing the role of neuroprotective agents. This review will target the therapeutic potential of various phytochemicals which shows neuroprotective action.

An Alternative Device for the Topical Treatment of Oral Cancer: Development and Ex-Vivo Evaluation of Imiquimod-Loaded Polysaccharides Formulations

The topical use of imiquimod (IMQ), a non-specific immune response modifier, showed to be a promising therapeutic option for the early-stage treatment of some type of oral cancer, even when performed with a formulation (Aldara®) developed and approved for skin application. The aim of this work was the development of buccal formulations for the topical administration of IMQ with improved mucosal retention and reduced trans-mucosal permeation when compared to the reference formulation. Three different hydrogels based on carboxymethyl chitosan (CMChit), sodium alginate (A), and xanthan gum (X) in different combinations were prepared, and the loading of imiquimod was successfully performed by using a micellar formulation based on d-α-tocopheril polyethylene glycol 100 succinate (TPGS). Except for CMChit formulation, in all the other cases, the performance in vitro on the mucosa resulted comparable to the commercial formulation, despite the drug loading being 50-fold lower. Converting the gels in films did not modify the IMQ accumulated with respect to the correspondent gel formulation but produced as a positive effect a significant reduction in the amount permeated. Compared to the commercial formulation, this reduction was significant (p < 0.01) in the case of X film, resulting in an improvement of the retained/permeated ratio from 1 to 5.44. Mucoadhesion evaluation showed similar behavior when comparing the developed gels and the commercial formulation, and an excellent bioadhesion was observed for the films.

Hyperoside-loaded TPGs/mPEG-PDLLA self-assembled polymeric micelles: preparation, characterization and in vitro/in vivo evaluation

Hyperoside (Hyp) self-assembled polymeric micelles (Hyp-PMs) were purposely developed to enhance aqueous solubility, in vivo availability and anti-oxidative effect of Hyp. In preparing Hyp-PMs, we employed the thin film dispersion method with the micelles consisting of TPGs and mPEG2000-PDLLA3000. The particle size, polydispersity index and zeta potential of Hyp-PMs were 67.42 ± 1.44 nm, 0.229 ± 0.015 and -18.67 ± 0.576 mV, respectively, coupled with high encapsulation efficiency (EE)of 90.63 ± 1.45% and drug loading (DL) of 6.97 ± 1.56%. Furthermore, the value of critical micelle concentration (CMC) was quite low, which indicated good stability and improved self-assembly ability of Hyp-PMs. Also, trend of in vitro Hyp release from Hyp-PMs demonstrated enhanced solubility of Hyp. Similarly, in comparison with free Hyp, oral bioavailability of Hyp-PMs was improved (about 8 folds) whilst half-life of Hyp-PMs was extended (about 3 folds). In vitro anti-oxidative effect showed obvious strong scavenging DPPH capability of Hyp-PMs, which may be attributed to its smaller size and better solubility. Altogether, Hyp-PMs may serve as a possible strategy to potentially enhance aqueous solubility, bioavailability and anti-oxidative effect of Hyp, which may play a key role in Hyp application in the pharmaceutical industries.

Engineered Nanoscale Lipid-Based Formulation as Potential Enhancer of Gefitinib Lymphatic Delivery: Cytotoxicity and Apoptotic Studies Against the A549 Cell Line

The present study aimed to engineer a nanoscale lipid-based lymphatic drug delivery system with D-α-Tocopherol polyethylene glycol 1000 succinate to combat the lymphatic metastasis of lung cancer. The nanoscale lipid-based systems including GEF-SLN, GEF-NLC, and GEF-LE were prepared and pharmaceutically characterized. In addition, the most stable formulation (GEF-NLC) was subjected to an in vitro release study. Afterward, the optimized GEF-NLC was engineered with TPGS (GEF-TPGS-NLC) and subjected to in vitro cytotoxicity, and apoptotic studies using the A549 cells line as a surrogate model for lung cancer. The present results revealed that particle size and polydispersity index of freshly prepared formulations were ranging from 198 to 280 nm and 0.106 to 0.240, respectively, with negative zeta potential ranging from − 14 to − 27.6.mV. An in vitro release study showed that sustained drug release was attained from GEF-NLC containing a high concentration of lipid. In addition, GEF-NLC and GEF-TPGS-NLC showed remarkable entrapment efficiency above 89% and exhibited sustained release profiles. Cytotoxicity showed that IC₅₀ of pure GEF was 11.15 μg/ml which decreased to 7.05 μg/ml for GEF-TPGS-NLC. The apoptotic study revealed that GEF-TPGS-NLC significantly decreased the number of living cells from 67 to 58% when compared with pure GEF. The present results revealed that the nanoscale and lipid composition of the fabricated SLN, NLC, and LE could mediate the lymphatic uptake of GEF to combat the lymphatic tumor metastasis. Particularly, GEF-TPGS-NLC is a promising LDDS to increase the therapeutic outcomes of GEF during the treatment of metastatic lung cancer.

R-α-Lipoic Acid Conjugated to d-α-Tocopherol Polyethylene Glycol 1000 Succinate: Synthesis, Characterization, and Effect on Antiseizure Activity

α-Lipoic acid (LA), a dithiol micronutrient, acts as a vital cofactor in various cellular catabolic reactions and is also known as a universal antioxidant. The therapeutic efficacy of LA is compromised by a poor aqueous solubility as well as a short half-life. In the present study, LA was conjugated to d-α-tocopherol polyethylene glycol succinate (TPGS) using carbodiimideacid-alcohol coupling reaction. The synthesized conjugate (TPGS-LA) was characterized using ¹H and ¹³C nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), UV-vis spectroscopy, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The TPGS-LA conjugate was demonstrated to be biocompatible and to have better anticonvulsion activity as compared to native LA in pentylenetetrazol (PTZ)-induced convulsions in zebrafish. Moreover, zebrafish larvae pretreated with TPGS-LA conjugate demonstrated a significant (p < 0.05) reduction of protein carbonylation levels and downregulation of c-fos expression during seizures as compared to native LA. Conclusively, the present findings demonstrate that the TPGS-LA conjugate can be a promising approach for the delivery of LA.

An Oral 3D Printed PLGA-Tocopherol PEG Succinate Nanocomposite Hydrogel for High-Dose Methotrexate Delivery in Maintenance Chemotherapy

High-dose methotrexate (HDMTX) is one of the chemotherapeutic agents used to treat a variety of cancers in both adults and children. However, the toxicity associated with HDMTX has resulted in the spread of infections and treatment interruption. Further, poor bioavailability due to efflux pump activities mediated by P-glycoprotein has also been linked to poor therapeutic effects of methotrexate following oral administrations. D-α-Tocopheryl poly-ethylene glycol 1000 succinate (TPGS) is known to improve the bioavailability of poorly soluble drugs by inhibiting P-gp efflux activities, thus enhancing cellular uptake. Therefore, to achieve improved bioavailability for MTX, this study aimed to design and develop a novel drug delivery system employing TPGS and a biodegradable polymer, i.e., PLGA, to construct methotrexate-loaded nanoparticles fixated in alginate-gelatine 3D printable hydrogel ink to form a solid 3D printed tablet for oral delivery. The results indicated that high accuracy (>95%) of the 3D printed tablets was achieved using a 25 G needle. In vitro, drug release profiles were investigated at pH 1.2 and pH 7.4 to simulate the gastrointestinal environment. The in vitro release profile displayed a controlled and prolonged release of methotrexate over 24 h. The in silico modeling study displayed P-gp ATPase inhibition, suggesting enhanced MTX absorption from the gastrointestinal site. The 3D-printed hydrogel-based tablet has the potential to overcome the chemotherapeutic challenges that are experienced with conventional therapies.

Solid Dispersions Incorporated into PVP Films for the Controlled Release of Trans-Resveratrol: Development, Physicochemical and In Vitro Characterizations and In Vivo Cutaneous Anti-Inflammatory Evaluation

Trans-resveratrol can promote various dermatological effects. However, its high crystallinity decreases its solubility and bioavailability. Therefore, solid dispersions have been developed to promote its amorphization; even so, they present as powders, making cutaneous controlled drug delivery unfeasible and an alternative necessary for their incorporation into other systems. Thus, polyvinylpyrrolidone (PVP) films were chosen with the aim of developing a controlled delivery system to treat inflammation and bacterial infections associated with atopic dermatitis. Four formulations were developed: two with solid dispersions (and trans-resveratrol) and two as controls. The films presented with uniformity, as well as bioadhesive and good barrier properties. X-ray diffraction showed that trans-resveratrol did not recrystallize. Fourier-transform infrared spectroscopy (FT-IR) and thermal analysis evidenced good chemical compatibilities. The in vitro release assay showed release values from 82.27 ± 2.60 to 92.81 ± 2.50% (being a prolonged release). In the in vitro retention assay, trans-resveratrol was retained in the skin, over 24 h, from 42.88 to 53.28%. They also had low cytotoxicity over fibroblasts. The in vivo assay showed a reduction in inflammation up to 66%. The films also avoided Staphylococcus aureus’s growth, which worsens atopic dermatitis. According to the results, the developed system is suitable for drug delivery and capable of simultaneously treating inflammation and infections related to atopic dermatitis.

Self-Assembled Nanomicellar Formulation of Docetaxel as a Potential Breast Cancer Chemotherapeutic System

Docetaxel (DTX) is classified as a class IV drug that exhibits poor aqueous solubility (6–7 µg/mL in water) and permeability (P-glycoprotein substrate). The main objective of this study was to construct, characterize, and evaluate docetaxel loaded nanomicellar formulation in vitro for oral delivery to enhance the absorption and bioavailability of DTX, as well as to circumvent P-gp efflux inhibition. Formulations were prepared with two polymeric surfactants, hydrogenated castor oil-40 (HCO-40) and D-α-Tocopherol polyethylene glycol 1000 succinate (VIT E TPGS) with solvent evaporation technique, and the resulting DTX nanomicellar formulations were characterized by proton nuclear magnetic resonance spectroscopy (1H NMR), Fourier Transform Infrared Spectroscopy (FT–IR), X-ray powder diffraction (XRD), and transmission electron microscopy (TEM). Proton NMR, FT–IR, and XRD data indicated that DTX was completely encapsulated within the hydrophobic core of the nanomicelles in its amorphous state. TEM data revealed a smooth spherical shape of the nanomicellar formulation. The optimized formulation (F-2) possessed a mean diameter of 13.42 nm, a zeta potential of −0.19 mV, with a 99.3% entrapment efficiency. Dilution stability study indicated that nanomicelles were stable up to 100-fold dilution with minimal change in size, poly dispersity index (PDI), and zeta potential. In vitro cytotoxicity study revealed higher anticancer activity of DTX nanomicelles at 5 µM compared to the native drug against breast cancer cell line (MCF-7) cells. The LC–MS data confirmed the chemical stability of DTX within the nanomicelles. In vitro drug release study demonstrated faster dissolution of DTX from the nanomicelles compared to the naked drug. Our experimental results exhibit that nanomicelles could be a drug delivery system of choice to encapsulate drugs with low aqueous solubility and permeability that can preserve the stability of the active constituents to provide anticancer activity.

Posaconazole micelles for ocular delivery: in vitro permeation, ocular irritation and antifungal activity studies

Posaconazole (PSC) is a triazole group anti-fungal agent with the widest spectrum. Although there is no commercially available ocular dosage form, its diluted oral suspension preparation (Noxafil®) is used as off-label in topical treatment of severe keratitis and sclerokeratitis in the clinic. However, ocular bioavailability of PSC suspension form is extremely low due to its highly lipophilic character. Thus, there is a clinical need to improve its ocular bioavailability and to develop novel delivery system for the treatment of ocular fungal infections. Herein, we studied ex vivo permeation, penetration, anti-fungal activity, and Hen's Egg Test-Chorioallantoic Membrane (HET-CAM) toxicity tests in order to assess ocular targeting of PSC micelles, which were optimized in our previous study. The results indicated that micellar carrier system increased the permeability of PSC to eye tissues. Micelles showed higher affinity to ocular tissues than that of commercial oral suspension of PSC (Noxafil®). In vitro anti-fungal activity data also confirmed the efficacy of PSC loaded micellar formulations against Candida. albicans strains. The relative safety of the optimized micelles on the ocular tissue was shown with the HET-CAM toxicity test. In conclusion, micellar systems could be a promising strategy for the effective and safe delivery of PSC in the treatment of ocular fungal infections.

Before in vivo studies: In vitro screening of sphingomyelin nanosystems using a relevant 3D multicellular pancreatic tumor spheroid model

Sphingomyelin nanosystems have already shown to be promising carriers for efficient delivery of anticancer drugs. For further application in the treatment of pancreatic tumor, the investigation on relevant in vitro models able to reproduce its physio-pathological complexity, is mandatory. Accordingly, a 3D heterotype spheroid model of pancreatic tumor has been herein constructed to investigate the potential of bare and polyethylene glycol-modified lipids nanosystems in terms of their ability to penetrate the tumor mass and deliver drugs. Regardless of their surface properties, the lipid nanosystems successfully diffused through the spheroid without inducing toxicity, showing a clear safety profile. Loading of the bare nanosystems with a lipid prodrug of gemcitabine was used to evaluate their therapeutic potential. While the nanosystems were more effective than the free drug on 2D cell monocultures, this advantage, despite their efficient penetration capacity, was lost in the 3D tumor model. The latter, being able to mimic the tumor and its microenvironment, was capable to provide a more realistic information on the cell sensitivity to treatments. These results highlight the importance of using appropriate 3D tumour models as tools for proper in vitro evaluation of nanomedicine efficacy and their timely optimisation, so as to identify the best candidates for later in vivo evaluation.

Vitamin E Oil Incorporated Liposomal Melphalan and Simvastatin: Approach to Obtain Improved Physicochemical Characteristics of Hydrolysable Melphalan and Anticancer Activity in Combination with Simvastatin Against Multiple Myeloma

The objective of this research was to develop vitamin E oil (VEO)-loaded liposomes for intravenous delivery and to study the VEO effect on melphalan (MLN) loading, release, and stability. Further, the research aim was to determine the in vitro anticancer activity and in vivo systemic toxicity of MLN and simvastatin (SVN) combinations, for repurposing SVN in multiple myeloma. The liposomes were prepared by thin-film hydration technique. The optimized liposomes were surface modified with Pluronic F108, lyophilized, and evaluated for mean particle size, MLN content and release behavior, and in vitro hemolysis, cytotoxicity, and macrophage uptake characteristics. Further, in vivo acute toxicity of plain MLN + SVN combination was determined in comparison to their liposomal combination. The VEO alone and in combination with D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) has significantly increased the MLN and SVN loading. The reconstituted liposomes showed the mean particle size below 200 nm (cryo-transmission electron microscope analysis also revealed the liposome formation). In presence of VEO, the liposomes have shown substantially controlled drug release, lower hemolysis, sustained cytotoxicity, lower phagocytosis, and moderately improved chemical stability. Besides, the effect of liposomal combination on mice bodyweight is found substantially lower than the plain drug combination. In conclusion, the VEO could be used along with phospholipids and cholesterol to develop liposomal drugs with improved physicochemical characteristics. Further, the interesting cytotoxicity study results indicated that SVN could be repurposed in combination with anticancer drug MLN against multiple myeloma; liposomal drugs could be preferred to obtain improved efficacy with decreased systemic toxicity.

Improvement of Imiquimod Solubilization and Skin Retention via TPGS Micelles: Exploiting the Co-Solubilizing Effect of Oleic Acid

Imiquimod (IMQ) is an immunostimulant drug approved for the topical treatment of actinic keratosis, external genital-perianal warts as well as superficial basal cell carcinoma that is used off-label for the treatment of different forms of skin cancers, including some malignant melanocytic proliferations such as lentigo maligna, atypical nevi and other in situ melanoma-related diseases. Imiquimod skin delivery has proven to be a real challenge due to its very low water-solubility and reduced skin penetration capacity. The aim of the work was to improve the drug solubility and skin retention using micelles of d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS), a water-soluble derivative of vitamin E, co-encapsulating various lipophilic compounds with the potential ability to improve imiquimod affinity for the micellar core, and thus its loading into the nanocarrier. The formulations were characterized in terms of particle size, zeta potential and stability over time and micelles performance on the skin was evaluated through the quantification of imiquimod retention in the skin layers and the visualization of a micelle-loaded fluorescent dye by two-photon microscopy. The results showed that imiquimod solubility strictly depends on the nature and concentration of the co-encapsulated compounds. The micellar formulation based on TPGS and oleic acid was identified as the most interesting in terms of both drug solubility (which was increased from few µg/mL to 1154.01 ± 112.78 µg/mL) and micellar stability (which was evaluated up to 6 months from micelles preparation). The delivery efficiency after the application of this formulation alone or incorporated in hydrogels showed to be 42- and 25-folds higher than the one of the commercial creams.

Lung Targeted Lipopolymeric Microspheres of Dexamethasone for the Treatment of ARDS

Acute respiratory distress syndrome (ARDS), a catastrophic illness of multifactorial etiology, involves a rapid upsurge in inflammatory cytokines that leads to hypoxemic respiratory failure. Dexamethasone, a synthetic corticosteroid, mitigates the glucocorticoid-receptor-mediated inflammation and accelerates tissue homeostasis towards disease resolution. To minimize non-target organ side effects arising from frequent and chronic use of dexamethasone, we designed biodegradable, lung-targeted microspheres with sustained release profiles. Dexamethasone-loaded lipopolymeric microspheres of PLGA (Poly Lactic-co-Glycolic Acid) and DPPC (Dipalmitoylphosphatidylcholine) stabilized with vitamin E TPGS (D-α-tocopheryl polyethylene glycol succinate) were prepared by a single emulsion technique that had a mean diameter of 8.83 ± 0.32 μm and were spherical in shape as revealed from electron microscopy imaging. Pharmacokinetic and biodistribution patterns studied in the lungs, liver, and spleen of Wistar rats showed high selectivity and targeting efficiency for the lung tissue (re 13.98). As a proof-of-concept, in vivo efficacy of the microspheres was tested in the lipopolysaccharide-induced ARDS model in rats. Inflammation markers such as IL-1β, IL-6, and TNF-α, quantified in the bronchoalveolar lavage fluid indicated major improvement in rats treated with dexamethasone microspheres by intravenous route. Additionally, the microspheres substantially inhibited the protein infiltration, neutrophil accumulation and lipid peroxidation in the lungs of ARDS bearing rats, suggesting a reduction in oxidative stress. Histopathology showed decreased damage to the pulmonary tissue upon treatment with the dexamethasone-loaded microspheres. The multipronged formulation technology approach can thus serve as a potential treatment modality for reducing lung inflammation in ARDS. An improved therapeutic profile would help to reduce the dose, dosing frequency and, eventually, the toxicity.

Amphiphilic tocopheryl polyethylene glycol succinate as gas chromatographic stationary phase for high-resolution separations of challenging isomers and analysis of lavender essential oil

This work presents the investigation of using tocopheryl polyethylene glycol succinate as the stationary phase for gas chromatography separations of isomers with different varieties and gas chromatography-mass spectrometry analysis of a wide range of components in lavender essential oil. Its capillary column exhibited moderate polarity and column efficiency of 4000 plates/m determined by n-dodecane at 120°C. As demonstrated, it showed outstanding separation performance toward challenging isomers such as xylenes, alkanes, phenols, and anilines and a wide range of components in essential oils with distinct advantages over the commercial polyethylene glycol and polysiloxane columns. Moreover, its capillary columns displayed excellent repeatability and reproducibility with the RSD values of the retention times in the range of 0.02-0.07% for run-to-run, 0.14-0.22% for day-to-day, and 2.5-4.3% for column-to-column. Its application to gas chromatography-mass spectrometry analysis of the lavender essential oil proved its good potential for practical gas chromatography analyses. To our knowledge, this work presents the first example of employing tocopheryl polyethylene glycol succinate for chromatographic analyses and demonstrates its promising future in this field.

Enhanced Bioavailability and Efficacy of Silymarin Solid Dispersion in Rats with Acetaminophen-Induced Hepatotoxicity

We evaluated the bioavailability, liver distribution, and efficacy of silymarin-D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) solid dispersion (silymarin-SD) in rats with acetaminophen-induced hepatotoxicity (APAP) compared with silymarin alone. The solubility of silybin, the major and active component of silymarin, in the silymarin-SD group increased 23-fold compared with the silymarin group. The absorptive permeability of silybin increased by 4.6-fold and its efflux ratio decreased from 5.5 to 0.6 in the presence of TPGS. The results suggested that TPGS functioned as a solubilizing agent and permeation enhancer by inhibiting efflux pump. Thus, silybin concentrations in plasma and liver were increased in the silymarin-SD group and liver distribution increased 3.4-fold after repeated oral administration of silymarin-SD (20 mg/kg as silybin) for five consecutive days compared with that of silymarin alone (20 mg/kg as silybin). Based on higher liver silybin concentrations in the silymarin-SD group, the therapeutic effects of silymarin-SD in hepatotoxic rats were evaluated and compared with silymarin administration only. Elevated alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase levels were significantly decreased by silymarin-SD, silymarin, and TPGS treatments, but these decreases were much higher in silymarin-SD animals than in those treated with silymarin or TPGS. In conclusion, silymarin-SD (20 mg/kg as silybin, three times per day for 5 days) exhibited hepatoprotective properties toward hepatotoxic rats and these properties were superior to silymarin alone, which may be attributed to increased solubility, enhanced intestinal permeability, and increased liver distribution of the silymarin-SD formulation.