Effect of fixed aqueous layer thickness of polymeric stabilizers on zeta potential and stability of aripiprazole nanosuspensions

Encapsulation of hydrophobically ion-paired teduglutide in nanoemulsions: Effect of anionic counterions

This study presents a novel method for encapsulating the bioactive peptide teduglutide to enhance its oral bioavailability using O/W nanoemulsion (NE). Recombinant teduglutide (rTGT), produced in E. coli with 93 % purity, was hydrophobically modified through ion-pairing with phytic acid (PA) and sodium dodecyl sulfate (SDS). This approach increased encapsulation efficiency from 48.5 % to 87.5 % and 88.3 %, respectively. rTGT/SDS was incorporated within the core of lipid particles, whereas rTGT/PA was likely oriented on the surface. rTGT/SDS_NE exhibited smaller particle size, greater stability, and low cytotoxicity across all tested concentrations in HT-29 cells. Additionally, rTGT/SDS_NE achieved the highest upregulation of genes associated with intestinal function (VIL1, SGLT1, and GLUT2), although the differences were not statistically significant. These findings highlight the potential of the hydrophobic ion-pairing of rTGT with SDS and its encapsulation in nanoemulsion for efficient delivery of rTGT, suggesting promise for advancing oral peptide therapeutics.

Biological and computational assessments of thiazole derivative-reinforced bile salt enriched nano carriers: a new gate in targeting SARS-CoV-2 spike protein

There is merit in investigating novel therapeutic molecules that hit vital targets during the viral infection cycle i.e. disrupting the interaction between SARS-CoV-2's spike glycoprotein and the host's angiotensin converting enzyme 2 (ACE2) receptor, potentially offering new avenues for treatment. Accordingly, lipid-based vesicular systems like liposomes or niosomes are frequently utilized to overcome these hurdles. Thus, chemically synthesized compounds were encapsulated within PEGylated bilosomes (PBs) to improve their solubility and intestinal permeability, thereby enhancing their anti-SARS-CoV-2 effectiveness. The formulae were prepared according to 23 full factorial design which was also used to explore the impact of the change in predetermined formulation variables on the properties of the prepared vesicles (entrapment efficiency EE%, particle size PS, and zeta potential ZP). Additionally, the optimized formula (F4) which is composed of 3% bile salt (BS), 40 mg 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE) and sodium deoxycholate (SDC) as a bile salt, was selected as an optimum formula with desirability value 0.674 using Design Expert® software. Both the in vitro release and ex vivo experiments results confirmed the significant superiority of the F4 over the drug dispersion. Both cytotoxicity and anti-SARS-CoV-2 activity of all examined compound-loaded PBs (PB3a-PB3g) were assessed in Vero E6 cells via MTT assay. Both compounds PB3c and PB3g displayed the highest IC50 values (0.71 and 1.25 μg mL-1, respectively) ensuring their superior antiviral potential. Moreover, it was revealed that PB3c demonstrated more than 80% virucidal activity and over 80% inhibition of viral adsorption with little effect on the viral replication ∼(5-10%). Moreover, molecular docking and dynamic studies were conducted to pursue the binding affinities of the investigated compounds towards the ACE2 target of the SARS-CoV-2 spike protein, assuring their feasible inhibitory potential. Collectively, the investigated compound-loaded PBs can be treated as promising lead drug delivery panels for COVID-19 management.

Inulin Amphiphilic Copolymer-Based Drug Delivery: Unraveling the Structural Features of Graft Constructs

In this study, the structural attributes of nanoparticles obtained by a renewable and non-immunogenic "inulinated" analog of the "pegylated" PLA (PEG-PLA) were examined, together with the potential of these novel nanocarriers in delivering poorly water-soluble drugs. Characterization of INU-PLA assemblies, encompassing critical aggregation concentration (CAC), NMR, DLS, LDE, and SEM analyses, was conducted to elucidate the core/shell architecture of the carriers and in vitro cyto- and hemo-compatibility were assayed. The entrapment and in vitro delivery of sorafenib tosylate (ST) were also studied. INU-PLA copolymers exhibit distinctive features: (1) Crew-cut aggregates are formed with coronas of 2-4 nm; (2) a threshold surface density of 1 INU/nm2 triggers a configuration change; (3) INU surface density influences PLA core dynamics, with hydrophilic segment stretching affecting PLA distribution towards the interface. INU-PLA2NPs demonstrated an outstanding loading of ST and excellent biological profile, with effective internalization and ST delivery to HepG2 cells, yielding a comparable IC50.

Indocyanine green-mediated fabrication of urchin-like hydroxyethyl starch nanocarriers for enhanced drug tumor EPR and deep penetration effects

Effective EPR and tumor penetration are bottlenecks in current nanomedicine therapy. Comosol software was utilized to analyze the motion process of nanoparticles (NPs) with different shapes, from blood vessels to tumor tissue, to address this. By calculation, urchin-like NPs experienced higher drag forces than spherical NPs, facilitating their EPR and tumor penetration effects. Thus, urchin-like indocyanine green-loaded hydroxyethyl starch-cholesterol (ICG@HES-CH) NPs were prepared by leveraging the instability of ICG responding to near-infrared light (NIR). Upon NIR exposure, ICG degraded and partly disintegrated ICG@HES-CH NPs, and its morphology transformed from spherical to urchin-like. Vincristine (VC), as a model drug, was loaded in urchin-like ICG@HES-CH NPs for the treatment of lymphoma. A20 lymphoma cells and 3T3-A20 tumor organoids were employed to investigate the influence of shape on NPs' cellular uptake, penetration pathway, and cytotoxicity. It demonstrated that urchin-like ICG@HES-CH NPs mainly transport across the extracellular matrix through intercellular pathways, easily reaching the deep tumor sites and achieving higher cytotoxicity. In vivo VC distribution and anti-tumor results indicated that urchin-like NPs increased VC EPR and penetration ability, lowering VC neurotoxicity and superior anti-tumor effect. Therefore, urchin-like ICG@HES-CH NPs have great translational potential to be used as chemotherapeutic nanocarriers in anticancer therapy.

QbD Enabled Development and Evaluation of Pazopanib Loaded Nanoliposomes for PDAC Treatment

Pancreatic ductal adenocarcinoma (PDAC) is one of the highly fatal types of cancer with high mortality/incidence. Considering the crucial role of vascular endothelial growth factor (VEGF) in PDAC progression, its inhibition can be a viable strategy for the treatment. Pazopanib, a second-generation VEGF inhibitor, is approved for the treatment of various oncological conditions. However, due to associated limitations like low oral bioavailability (14-39%), high inter/intra-subject variability, stability issues, etc., high doses (800 mg) are required, which further lead to non-specific toxicities and also contribute toward cancer resistance. Thus, to overcome these challenges, pazopanib-loaded PEGylated nanoliposomes were developed and evaluated against pancreatic cancer cell lines. The nanoliposomes were prepared by thin-film hydration method, followed by characterization and stability studies. This QbD-enabled process design successfully led to the development of a suitable pazopanib liposomal formulation with desirable properties. The % entrapment of PZP-loaded non-PEGylated and PEGylated nanoliposomes was found to be 75.2% and 84.9%, respectively, whereas their particle size was found to be 129.7 nm and 182.0 nm, respectively. The developed liposomal formulations exhibited a prolonged release and showed desirable physicochemical properties. Furthermore, these liposomal formulations were also assessed for in vitro cell lines, such as cell cytotoxicity assay and cell uptake. These studies confirm the effectiveness of developed liposomal formulations against pancreatic cancer cell lines. The outcomes of this work provide encouraging results and a way forward to thoroughly investigate its potential for PDAC treatment.

Cyclodextrin-based tailored polyrotaxanes for highly efficient delivery of the genome-editing molecule

Direct cytosolic delivery of the Cas9 ribonucleoprotein is the most promising method for inducing CRISPR-Cas9 genome editing in mammalian cells. Recently, we focused the movable properties of cyclodextrin-based polyrotaxanes (PRXs), which consist of numerous cyclodextrins threaded onto the axile molecule with bulky endcaps at both ends of the axile molecule, and developed aminated PRXs as multistep transformable carriers for Cas9 ribonucleoprotein, ensuring efficient complexation, cellular internalization, endosomal escape, release, and nuclear localization. This study reports the structural fine-tuning and structure-property relationship of multistep transformable PRXs for more efficient Cas9 ribonucleoprotein delivery. Among various PRXs, PRX derivatives with a longer molecular length (35 kDa polyethylene glycol as the axile molecule) and a low total degree of substitution (1.5 amino groups/α-cyclodextrins), as well as the modified ratio of two modified amines (cystamine and diethylenetriamine) = ≈1:1, exhibited the highest genome-editing efficacy and intracellular dynamics control. These structural properties are important for efficient endosomal escape and Cas9 RNP release. Furthermore, ligand-modified-β-CD, which can endow the ligand through complexation with PRX termini, improved the cellular uptake and genome-editing effects of the optimized PRX/Cas9 RNP in target cells. Thus, structural fine-tuning and the addition of ligand-modified-β-cyclodextrin enabled efficient genome editing by the Cas9 RNP.

Preparation and Characterization of Nanosuspensions of Triiodoaniline Derivative New Contrast Agent, and Investigation into Its Cytotoxicity and Contrast Properties

Iodine-based contrast agents have limitations such as rapid clearance, potential renal toxicity, non-specific blood pool distribution, headache, and adverse events. Nowadays, it is quite common to work with nanosized systems in order to eliminate the side effects of contrast agents. This study aims to synthesize a new iodinated contrast agent, prepare its nanosuspension by using the nanoprecipitation method, investigate its cytotoxicity, and compare its contrast properties with iohexol and iopromide through in-vitro experiments. The values of nanosuspension particle size and zeta potential have been found to be ~ 400 nm and ~ (-) 15 mV, respectively. In-vitro cellular viability findings indicated that the nanosuspension has lower cytotoxicity than the iohexol and iopromide. In the computed tomography (CT) imaging study of contrast features of nanosuspensions and two commercial agents, which involved 86 CT examinations using 31 parameters and two different devices, it was found that iodine had a stronger presence in its nanosuspension form than in iohexol and iopromide, which were the other two commercial contrast agents, when used in equal amounts. Thus in the case of nanosuspensions contrast brightness was achieved by using less iodine, while the same brightness could be obtained with higher doses of iohexol and iopromide. CT imaging therefore be done without much chemical use, which indicates that it may witness fewer side effects in the future.

Harnessing of Doxylamine Succinate/Pyridoxine Hydrochloride-Dual Laden Bilosomes as a Novel Combinatorial Nanoparadigm for Intranasal Delivery: In Vitro Optimization and In Vivo Pharmacokinetic Appraisal

The present work is concerned with tailoring and appraisal of a novel nano-cargo; bilosomes (BLS) dual laded with doxylamine succinate (DAS) and pyridoxine hydrochloride (PDH), the first treatment option against gestational nausea and vomiting, for intranasal delivery. This bifunctional horizon could surmount constraints of orally-commercialized platforms both in dosage regimen and pharmacokinetic profile. For accomplishing this purpose, DAS/PDH-BLS were elaborated integrating phospholipid, sodium cholate and cholesterol applying thin-film hydration method based on Box-Behnken design. Utilizing Design-Expert® software, the effect of formulation variables on BLS physicochemical features alongside the optimal formulation selection were investigated. Then, the optimum DAS/PDH-BLS formulation was incorporated into a thermally-triggered in situ gelling base. The in vivo pharmacokinetic studies were explored in rats for intranasal DAS/PDH-BLS in situ gel compared with analogous intranasal free in situ gel and oral solution. The optimized BLS disclosed vesicle size of 243.23 nm, ζ potential of -31.33 mV, entrapment efficiency of 59.18 and 41.63%, accumulative % release within 8 h of 63.30 and 85.52% and accumulative permeated amount over 24 h of 347.92 and 195.4 µg/cm² for DAS/PDH, respectively. Following intranasal administration of the inspected BLS in situ gel, pharmacokinetic studies revealed a 1.64- and 2.3-fold increment in the relative bioavailability of DAS and a 1.7- and 3.73-fold increase for PDH compared to the intranasal free in situ gel and oral solution, respectively besides significantly extended mean residence times for both drugs. Thus, the intranasally exploited DAS/PDH-BLS could be deemed as a promising hybrid nanoplatform with fruitful pharmacokinetics and tolerability traits.

Atomic Force Microscopy Study of Non-DLVO Interactions between Drops and Bubbles

The heterointeraction between liquid drops and air bubbles dispersed in another immiscible liquid is studied with the application of the atomic force microscopy (AFM) probe techniques. The tetradecane drops and air bubbles readily coalescence to form a lens-like structure in 100 mM sodium chloride aqueous solution, demonstrating strong hydrophobic (HB) attraction. The interaction range and strength of this hydrophobic attraction between oil drops and air bubbles is investigated by fine control of electrical double layer thicknesses related to specific electrolyte concentrations, and a midrange term in combination with a short-range term is found to present a proper characterization of this hydrophobic attraction. A further step is taken by introducing a triblock copolymer (Pluronic F68) into the aqueous solution, with results indicating that a relatively long-range steric hindrance (SH) furnished by a polymer "brush" surmounts the hydrophobic attraction. Finally, the interaction between a water drop and an air bubble in tetradecane is also measured as a comparison. The repelling action between a hydrophobic body (air bubble) and water drop indicates a strong repulsion. The present results show an interesting understanding of hydrophobic interactions between drops and bubbles, which is of potential application in controlling dispersion stability.

Norfloxacin loaded nano-cubosomes for enhanced management of otitis externa: In vitro and in vivo evaluation

The research's goal is to design and formulate nano-structured cubosomes loaded with norfloxacin (NFX)formanagement of otitis externa. In this study, glyceryl monooleate (GMO) as lipid phase, Cremophor EL as surfactant and either Pluronic F108 or Pluronic F127 as stabilizer were the used ingredients. The nano-cubosomal formulation "CUB 1" (its dispersed phase is composed of GMO (95%), Cremophor EL (2.5%) and Pluronic F108 (2.5%)) was the best achieved one. It had small particles size (216.75 ± 2.47 nm), good polydispersity index (0.339 ± 0.012) and acceptable zeta potential (-41.2 ± 2.262 mV). Images obtained after transmission electron microscopy examination ensured nearly cubic shape of formed nanoparticles with excellent dispersibility. Moreover, micrographs of rabbit ear skin specimens examined by confocal laser microscopy ensured good permeation capability of nano-structured cubosomes.In addition, in vivoskin deposition results revealed that higher amount of NFX was deposited in the rabbit ear skin throughout the study period (10 h) compared to drug suspension. Additionally, histopathological results proved that NFX loaded cubosomes can be safely applied topically on ear skin without any signs of inflammation nor skin irritation. Accordingly, these results anticipated the nano-structured cubosomal capabilities as a favorable nano-carrier for dermal NFX delivery to external ear skin for enhancing the management of otitis externa.

Fabrication of Highly Deformable Bilosomes for Enhancing the Topical Delivery of Terconazole: In Vitro Characterization, Microbiological Evaluation, and In Vivo Skin Deposition Study

The current study aimed to load terconazole (TCZ), an antifungal agent with low permeability characteristics, into highly deformable bilosomes (HBs) for augmenting its topical delivery. HBs contain edge activator in addition to the constituents of traditional bilosomes (Span 60, cholesterol, and bile salts). More elasticity is provided to the membrane of vesicles by the existence of edge activator and is expected to increase the topical permeation of TCZ. HBs were formulated using ethanol injection technique based on 2⁴ complete factorial design to inspect the impact of various formulation variables (bile salt type and amount, edge activator type, and sonication time) on HBs characteristics (entrapment efficiency percent (EE%), particle size (PS), polydispersity index (PDI), and zeta potential (ZP)). The optimum formula (HB14) was decided based on Design-Expert^® software and was utilized for further explorations. HB14 exhibited EE% = 84.25 ± 0.49%, PS = 400.10 ± 1.69 nm, PDI = 0.23 ± 0.01, and ZP = - 56.20 ± 0.00 mV. HB14 showed spherical vesicles with higher deformability index (9.94 ± 1.91 g) compared to traditional bilosomal formula (3.49 ± 0.49 g). Furthermore, HB14 showed superior inhibition of Candida albicans growth relative to TCZ suspension using XTT (2,3-bis(2-methyloxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) reduction assay. Moreover, in vivo skin deposition studies revealed superior TCZ deposition inside the skin from HB14 compared to traditional bilosomal formula and TCZ suspension. Moreover, histopathological examination in rats assured the safety of HB14 for topical use. Concisely, the obtained outcomes confirmed the pronounced efficacy of HBs for topical delivery of TCZ.

Use of Novasomes as a Vesicular Carrier for Improving the Topical Delivery of Terconazole: In Vitro Characterization, In Vivo Assessment and Exploratory Clinical Experimentation

Purpose

This manuscript aimed at encapsulating an antifungal terconazole (TCZ) into innovative novasomes for improving its penetration into the skin and clinically modulating its therapeutic efficacy.

Methods

Novasomes containing free fatty acid (FFA) as a penetration enhancer were formulated using ethanol injection technique based on 2⁴ full factorial design to explore the impact of various formulation variables on novasomes characteristics regarding entrapment efficiency percent (EE%), particle size (PS), polydispersity index (PDI), and zeta potential (ZP). The optimum formulation was chosen using Design-Expert^® software and utilized for further explorations.

Results

The chosen formulation (N15; including 100 mg lipid components and Span 80 to oleic acid in a ratio of 2:1 (w/w)) exhibited an EE% = 99.45 ± 0.78%, PS = 623.00 ± 2.97 nm, PDI = 0.40 ± 0.04, and ZP = −73.85 ± 0.64 mV. N15 showed spherical vesicles with a higher deformability index (DI) (9.62 ± 0.15 g) compared to traditional niosomal formulation (0.92 ± 0.12 g). Further, N15 showed superior inhibition of Candida albicans growth relative to TCZ suspension using XTT (2,3-bis-(2-methyloxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) reduction assay. Moreover, in vivo skin deposition tests revealed a superior TCZ deposition inside the skin from N15 in comparison to traditional niosomal formulation and TCZ suspension. Furthermore, histopathological examination for rats assured the safety of N15 for topical use. A clinical study conducted on infants suffering from napkin candidiasis proved the superiority of N15 to placebo in providing a complete cure of such fungal infections.

Conclusion

Concisely, the obtained outcomes confirmed the pronounced efficacy of N15 to successfully treat skin fungal infections.

Hexosomes as Efficient Platforms for Possible Fluoxetine Hydrochloride Repurposing with Improved Cytotoxicity against HepG2 Cells

The aim of this study was to investigate the feasibility of hexosomes (HEXs) as competent platforms for fluoxetine hydrochloride (FH) repurposing against HepG2 hepatocellular carcinoma. Different FH-loaded HEX formulations were prepared and optimized by the hot emulsification method. The HEX features such as particle size, ζ potential, and drug entrapment efficiency (EE%) can be tailored by tuning HEX components and fabrication conditions. The composition of the optimized FH hexosome (OFH-HEX) was composed of 3.1, 1.4, 0.5, 0.2, and 94.8% for glyceryl monooleate, oleic acid, pluronic F127, FH, and deionized water, respectively. The anionic OFH-HEX with a particle size of 145.5 ± 2.5 nm and drug EE% of 45.4 ± 1.2% was able to prolong the in vitro FH release, where only 19.5 ± 2.3% released in phosphate-buffered saline (PBS) pH 7.4 after 24 h. Contrarily, HEX rapidly released FH in acetate buffer pH 5.5 and achieved a 90.5 ± 4.7% release after 24 h. The obtained HEX showed an improved cellular internalization in a time-dependent manner and enhanced the cytotoxicity (2-fold higher than FH solution). The current study suggests the potential of FH-HEX as a possible anticancer agent against hepatocellular carcinoma.

Development of Polymer and Surfactant Based Naringenin Nanosuspension for Improvement of Stability, Antioxidant, and Antitumour Activity

Nanosuspensions are widely reported to enhance the solubility of poorly soluble drugs. In addition to enhancement in solubility, improvement of stability and therapeutic efficacy would be an added advantage. In the present study, premilling and subsequent high-pressure homogenization were carried out to produce naringenin nanosuspension. Hydroxypropyl methylcellulose and sodium dodecyl sulfate were evaluated for their performance as stabilizers under various homogenization cycles. The prepared nanosuspensions were studied for average particle size and size distribution, zeta potential, solubility, drug release, antioxidant activity, and in vitro antitumor activity. It was observed that both hydroxypropyl methylcellulose-stabilized nanosuspension and sodium dodecyl sulfate-stabilized nanosuspension produced an enhancement in physical stability, antioxidant potential, and in vitro cytotoxicity compared with naringenin. Furthermore, hydroxypropyl methylcellulose-stabilized nanosuspension was found to be better than sodium dodecyl sulfate-stabilized nanosuspension in terms of particle size and size distribution, storage stability, and drug release. This study showed that nanosuspension formulations could be a potential strategy for improving dissolution and antitumor activity of naringenin.

Study on the stabilization mechanisms of wet-milled cepharanthine nanosuspensions using systematical characterization

Objectives: Stability issues are inevitable problems that are encountered in nanosuspension (NS) technology developments and in the industrial application of pharmaceuticals. This study aims to assess the stability of wet-milled cepharanthine NSs and elucidate the stabilization mechanisms of different stabilizers.Methods: The aggregation state was examined via scanning electron microscopy, laser diffraction, and rheometry. The zeta potential, stabilizer adsorption, surface tension, and drug-stabilizer interactions were employed to elucidate the stabilization mechanisms.Results: The results suggest that croscarmellose sodium (CCS), D-α-tocopherol polyethylene glycol 1000 succinate (TPGS), or polyvinyl pyrrolidone VA64 (PVP VA64) alone was able to prevent nanoparticle aggregation for at least 30 days. Attempts to evaluate the stability mechanisms of different stabilization systems revealed that CCS improved the steric-kinetic stabilization of the NSs, attributed to its high viscosity, swelling capacity, and physical barrier effects. In contrast, the excellent physical stability of TPGS systems was mainly due to the reduced surface tension and higher crystallinity. PVP VA64 can adsorb onto the surfaces of nanoparticles and stabilize the NS via steric forces.Conclusion: This study demonstrated the complex effects of CCS, TPGS, and PVP VA64 on cepharanthine NS stability and presented an approach for the rational design of stable NSs.

Surface Exposure of PEG and Amines on Biodegradable Nanoparticles as a Strategy to Tune Their Interaction with Protein-Rich Biological Media

Nanoparticles (NPs) based on amphiphilic block copolymers of polyethylene glycol (PEG) and biodegradable polyesters are of particular current interest in drug nanodelivery due to their easily manipulated properties. The interaction of these NPs with biological environments is highly influenced by shell features, which drive biological identity after administration. To widen the strategies available for tuning particle surface chemistry, here we developed a panel of amine-bearing PEGylated NPs with a poly(ε-caprolactone) (PCL) core for the delivery of lipophilic drugs, and investigated the impact of NP modifications on their interaction with abundant circulating proteins (human serum albumin-HSA-and mucin), as well as their transport through biological barriers (artificial mucus-AM, extracellular matrix-ECM). We prepared NPs based on a diamino-terminated PCL (amine-NPs) and its mixture with PEG-PCL copolymers (amine/PEG-NPs) at different PEG molecular weights by nanoprecipitation, as well as corresponding NPs of PEG-PCL (PEG-NPs). The presence of an amine-bearing polymer resulted in NPs with a net positive charge and a zeta potential dependent on the length of PEG in the copolymer. Amine/PEG-NPs had a larger fixed aqueous layer thickness as compared to PEG-NPs, suggesting that PEG conformation is affected by the presence of positive charges. In general, amine-bearing NPs promptly interacted with the dysopsonic protein HSA, due to electrostatic interactions, and lose stability, thereby undergoing time-related aggregation. On the other hand, amine/PEG-NPs interaction with mucin induced switching to a negative surface charge but did not alter the quality of the dispersion. The transport kinetics of NPs through a layer of artificial mucus and tumor extracellular matrix was studied by means of fluorescent NPs based upon FRET. Amine/PEG-NPs did not cross the ECM, but they were promptly transported through the AM, with swifter transport noted at increasing MWs of PEG in the copolymer. Finally, we demonstrated that all the different NP types developed in this study are internalized by human monocytes and, despite the positive charge, they did not induce a measurable inflammatory effect. In conclusion, we showed that the concurrent presence of both PEG and amine groups on NP surface is a promising strategy for directing their interaction with body compartments. While PEG-NPs are confirmed for their capacity to cross ECM-like compartments, amine/PEG-NPs are revealed as a powerful platform to widen the arsenal of nanotools available for overcoming mucus-covered epithelia.

Hybrid Clustered Nanoparticles for Chemo-Antibacterial Combinatorial Cancer Therapy

Background: A great number of therapeutic limitations, such as chemoresistance, high dosage, and long treatments, are still present in cancer therapy, and are often followed by side effects such as infections, which represent the primary cause of death among patients. Methods: We report pH- and enzymatic-responsive hybrid clustered nanoparticles (HC-NPs), composed of a PCL polymeric core loaded with an anticancer drug, such as Imatinib Mesylate (IM), and coated with biodegradable multilayers embedded with antibacterial and anticancer baby-ship silver NPs, as well as a monoclonal antibody for specific targeting of cancer cells conjugated on the surface. Results: The HC-NPs presented an onion-like structure that serially responded to endogenous stimuli. After internalization into targeted cancer cells, the clustered nanoparticles were able to break up, thanks to intracellular proteases which degraded the biodegradable multilayers and allowed the release of the baby-ship NPs and the IM loaded within the pH-sensible polymer present inside the mothership core. In vitro studies validated the efficiency of HC-NPs in human chronic leukemic cells. This cellular model allowed us to demonstrate specificity and molecular targeting sensitivity, achieved by using a combinatorial approach inside a single nano-platform, instead of free administrations. The combinatory effect of chemotherapic drug and AgNPs in one single nanosystem showed an improved cell death efficacy. In addition, HC-NPs showed a good antibacterial capacity on Gram-negative and Gram-positive bacteria. Conclusions: This study shows an important combinatorial anticancer and antimicrobial effect in vitro.

Optimization and Evaluation of Beclomethasone Dipropionate Micelles Incorporated into Biocompatible Hydrogel Using a Sub-Chronic Dermatitis Animal Model

The current study is concerned with the development and characterization of mixed micelles intended for the dermal delivery of beclomethasone dipropionate, which is a topical corticosteroid used in the management of atopic dermatitis. Mixed micelles were prepared using thin-film hydration technique, employing different concentrations of pluronic L121 with either poloxamer P84 or pluronic F127 with different surfactant mixture-to-drug ratios. The prepared formulae were characterized concerning entrapment efficiency, particle size, and zeta potential. Two formulae were chosen for ex vivo skin deposition studies: one formulated using pluronic L121/poloxamer P84 mixture while the other using pluronic L121/pluronic F127 mixture. The optimum formula with the highest dermal deposition was subjected to morphological examination and was formulated as hydroxypropyl methylcellulose hydrogel. The hydrogel was evaluated regarding viscosity and was subjected to ex vivo deposition study in comparison with the commercially available cream Beclozone®. In vivo histopathological study was conducted for both the hydrogel and Beclozone® in order to evaluate their healing efficiency. In vivo histopathological study results showed that the prepared hydrogel successfully treated sub-chronic dermatitis in an animal model within a shorter period of time compared to Beclozone®, resulting in better patient compliance and fewer side effects.

Novel breviscapine nanocrystals modified by panax notoginseng saponins for enhancing bioavailability and synergistic anti-platelet aggregation effect

Breviscapine (BVP) is a flavonoid compound with strong neuroprotective and anti-platelet aggregation effect. The objective of this study is to design novel BVP nanocrystals modified by natural panax notoginseng saponins (PNS) for enhancing dissolution and anti-platelet aggregation effect of BVP. BVP nanocrystals modified by PNS (BVP-NC/PNS) were firstly prepared by coupling homogenization technology and freeze-drying technology, and BVP nanocrystals modified by RH40 (BVP-NC/RH40) as reference for comparison. The morphology, crystals characterization, dissolution behavior and anti-platelet aggregation effect of BVP-NC/PNS was systemically evaluated. The results demonstrated that the PNS could effectively maintain stability of BVP-NC at suspensions state dependent of its surface activity and the electrostatic repulsion effect. Combination of PNS and trehalose could prevent the aggregation of BVP-NC/PNS during freeze-drying. The PXRD and DSC results demonstrated that the BVP crystal state in BVP-NC/PNS was not changed owing to PNS modification and homogenization treatment. And the freeze-dried BVP-NC could easily recover back to BVP-NS and significantly improve the dissolution of BVP. The AUC_(0-∞) of the BVP-NC/PNS was 4.54 times as high as that of the coarse BVP, but not significantly different compared to that of BVP-NC/RH40 (p < 0.05). The anti-platelet aggregation results demonstrated that, BVP-NC/PNS group showed more effective inhibition on PAF-induced platelet aggregation compared with corresponding control groups, which might attribute to the enhanced bioavailability of BVP and synergistic effect of PNS with BVP. In conclusion, PNS could be used as an alternative stabilizer for preparation of BVP-NC, and BVP-NC modified by PNS is a promising formulation strategy for enhancing oral bioavailability and anti-platelet aggregation of BVP.

Sorbitan ester nanoparticles (SENS) as a novel topical ocular drug delivery system: Design, optimization, and in vitro/ex vivo evaluation

We explored the potential of two types of sorbitan ester nanoparticles (SENS) as novel tools for topical ocular drug delivery. The optimized SENS formulation (SENS-OPT) consisted of nanoparticles (NPs) of 170.5 nm, zeta potential +33.9 mV, and cyclosporine loading of 19.66%. After hyaluronic acid (HA) coating, the resulting SENS-OPT-HA NPs had a particle size of 177.6 nm and zeta potential of -20.6 mV. The NPs were stable during 3 months of storage at different temperatures and did not aggregate in the presence of protein-enriched simulated lacrimal fluid. There was no toxicity to cultured human corneal epithelial (HCE) cells when exposed to NPs up to 0.4% (w/v). Both NPs were effectively internalized by HCE cells through active mechanisms. Endocytosis of SENS-OPT NPs was caveolin-dependent whereas SENS-OPT-HA NP endocytosis was mediated by HA receptors. HA-receptor-mediated endocytosis may be responsible for the higher cellular uptake of SENS-OPT-HA NPs. After cyclosporine incorporation into the NPs, corneal penetration of this immunosuppressive drug by loaded SENS-OPT NPs was 1.3-fold higher than the commercial reference formulation Sandimmun®. For cyclosporine-loaded SENS-OPT-HA NPs, the penetration was 2.1-fold higher than for Sandimmun®. In ex vivo stimulated lymphocytes, both formulations demonstrated the same reduction in IL-2 levels as Sandimmun®.

A Natural Triterpenoid Saponin as Multifunctional Stabilizer for Drug Nanosuspension Powder

The objective of this study is to prepare a novel drug nanosuspension modified by a natural triterpenoid saponin (glycyrrhizin (GZ)) and evaluate its stability and redispersibility. A poorly soluble drug (andrographolide (AGE)) was used as a model drug. AGE nanosuspensions (AGE-NS) using GZ as natural stabilizer with mean particle size of 487 nm were firstly prepared by homogenization and converted into dried AGE nanosuspension powder (AGE-NP) by freeze-drying. It was found that GZ was able to prevent the aggregation of AGE nanocrystals and the freeze-dried AGE-NP could easily redisperse back to AGE-NS. It was related with special properties of GZ that possessed the interfacial property (37.02 ± 0.29 N/m) and electrostatic effect (-43.6 ± 0.9 mV) and could entrap AGE nanocrystals into its network structure. The freeze-dried AGE-NP/GZ exhibited excellent performance, compared with those combined with trehalose as matrix formers. The powder X-ray diffraction result demonstrated that GZ did not alter the AGE crystal state. The dissolution of AGE-NP/GZ (99.87%) was significantly enhanced, compared with the coarse AGE (42.35%). This study demonstrated that GZ could be used as a novel multifunctional stabilizer for production of drug nanosuspensions and provided a promising basis for further formulation development of poorly soluble drug.

Fabrication of novel ultradeformable bilosomes for enhanced ocular delivery of terconazole: In vitro characterization, ex vivo permeation and in vivo safety assessment

The objective of this work was to encapsulate terconazole (TCZ), a water insoluble antifungal drug, into novel ultradeformable bilosomes (UBs) for achieving enhanced ocular delivery. In addition to the constituents of the conventional bilosomes; namely, Span 60, cholesterol, and the bile salts, UBs contain an edge activator which imparts extra elasticity to the vesicles and consequently hypothesized to result in improved corneal permeation. In this study, TCZ loaded UBs were prepared utilizing ethanol injection method according to 2³ full factorial design. The investigation of the influence of different formulation variables on UBs properties and selection of the optimum formulation was done using Design-Expert^® software. The selected UBs formulation (UB1; containing 10mg bile salt and 5mg Cremophor EL as an edge activator) showed nanosized spherical vesicles (273.15±2.90nm) and high entrapment efficiency percent (95.47±2.57%). Results also revealed that the optimum UBs formulation exhibited superior ex vivo drug flux through rabbit cornea when compared with conventional bilosomes, niosomes, and drug suspension. Furthermore, in vivo ocular tolerance and histopathological studies conducted using male albino rabbits proved the safety of the fabricated UBs after topical ocular application. Overall, the obtained results confirmed that UBs could be promising for ocular drug delivery.

Methotrexate Nanoparticles Prepared with Codendrimer from Polyamidoamine (PAMAM) and Oligoethylene Glycols (OEG) Dendrons: Antitumor Efficacy in Vitro and in Vivo

The novel methotrexate-loaded nanoparticles (MTX/PGD NPs) prepared with amphiphilic codendrimer PGD from polyamidoamine and oligothylene glycol dendrons were obtained via antisolvent precipitation method augmented by ultrasonication. Based on the excellent hydrophility of PGD, the drug-loaded nanoparticles could be investigated easily with the high drug-loading content (~85.2%, w/w). The MTX/PGD NPs possessed spherical morphology, nanoscaled particle size (approximately 182.4 nm), and narrow particle size distribution. Release of MTX from MTX/PGD NPs showed a sustained release manner and completed within 48 h. Hemolytic evaluation indicated MTX/PGD NPs presented good blood compatibility, and the cytotoxicity of nanoparticles against breast cancer cells in vitro, biodistribution in tumor tissue, and antitumor efficacy in vivo were enhanced significantly compared to MTX injection. According to the higher drug-loading content, enhanced antitumor efficacy, and appropriate particle size, MTX/PGD NPs as the drug delivery systems could have potential application for cancer chemotherapy in clinic.

Preparation, optimization, and in vitro simulated inhalation delivery of carvedilol nanoparticles loaded on a coarse carrier intended for pulmonary administration

Carvedilol (CAR) is a potent antihypertensive drug but has poor oral bioavailability (24%). A nanosuspension suitable for pulmonary delivery to enhance bioavailability and bypass first-pass metabolism of CAR could be advantageous. Accordingly, the aim of this work was to prepare CAR nanosuspensions and to use artificial neural networks associated with genetic algorithm to model and optimize the formulations. The optimized nanosuspension was lyophilized to obtain dry powder suitable for inhalation. However, respirable particles must have a diameter of 1-5 µm in order to deposit in the lungs. Hence, mannitol was used during lyophilization for cryoprotection and to act as a coarse carrier for nanoparticles in order to deliver them into their desired destination. The bottom-up technique was adopted for nanosuspension formulation using Pluronic stabilizers (F127, F68, and P123) combined with sodium deoxycholate at 1:1 weight ratio, at three levels with two drug loads and two aqueous to organic phase volume ratios. The drug crystallinity was studied using differential scanning calorimetry and powder X-ray diffractometry. The in vitro emitted doses of CAR were evaluated using a dry powder inhaler sampling apparatus and the aerodynamic characteristics were evaluated using an Andersen MKII cascade impactor. The artificial neural networks results showed that Pluronic F127 was the optimum stabilizer based on the desired particle size, polydispersity index, and zeta potential. Results of differential scanning calorimetry combined with powder X-ray diffractometry showed that CAR crystallinity was observed in the lyophilized nanosuspension. The aerodynamic characteristics of the optimized lyophilized nanosuspension demonstrated significantly higher percentage of total emitted dose (89.70%) and smaller mass median aerodynamic diameter (2.80 µm) compared with coarse drug powder (73.60% and 4.20 µm, respectively). In summary, the above strategy confirmed the applicability of formulating CAR in the form of nanoparticles loaded on a coarse carrier suitable for inhalation delivery.

Nanosizing of a poorly soluble drug: technique optimization, factorial analysis, and pharmacokinetic study in healthy human volunteers

CONTEXT

Diacerein (DCN) has low aqueous solubility (3.197 mg/L) and, consequently, low oral bioavailability (35%-56%). To increase both the solubility and dissolution rate of DCN while maintaining its crystalline nature, high pressure homogenization was used but with only a few homogenization cycles preceded by a simple bottom-up technique.

METHODS

The nanosuspensions of DCN were prepared using a combined bottom-up/top-down technique. Different surfactants - polyvinyl alcohol, sodium deoxycholate, and sodium dodecyl sulfate - with different concentrations were used for the stabilization of the nanosuspensions. Full factorial experimental design was employed to investigate the influence of formulation variables on nanosuspension characteristics using Design-Expert(®) Software. Particle size (PS), zeta potential, saturation solubility, in vitro dissolution, and drug crystallinity were studied. Moreover, the in vivo performance of the optimized formula was assessed by bioavailability determination in healthy human volunteers.

RESULTS

The concentration of surfactant had a significant effect on both the PS and polydispersity index values. The 1% surfactant concentration showed the lowest PS and polydispersity index values compared with other concentrations. Both type and concentration of surfactant had significant effects on the zeta potential. Formula F8 (containing 1% sodium deoxycholate) and Formula F12 (containing 1% sodium dodecyl sulfate) had the highest desirability values (0.952 and 0.927, respectively). Hence, they were selected for further characterization. The saturated solubility and mean dissolution time, in the case of F8 and F12, were significantly higher than the coarse drug powder. Techniques utilized in the nanocrystals' preparation had no effect on DCN crystalline state. The selected formula (F12) showed a higher bioavailability compared to the reference market product with relative bioavailability of 131.4%.

CONCLUSION

The saturation solubility, in vitro dissolution rate and relative bioavailability of DCN were significantly increased after nanocrystallization. Less time and power consumption were applied by the combination of bottom-up and top-down techniques.

Development and characterization of lyophilized diazepam-loaded polymeric micelles

Polymeric micelles were studied as delivery carriers of diazepam, a practically insoluble drug in water, for rectal administration. The diazepam-loaded polymeric micelles were developed by using poloxamer 407 (P407), poloxamer 188, and D-α-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS). Among the used polymers, TPGS resulted in polymeric micelles with good characteristics for encapsulation of diazepam which had the small particle size of 8-12 nm and narrow size distribution (PI 0.053-0.275). Additionally, 7.5% w/v of TPGS could entirely entrap the desired concentration of diazepam (5 mg/mL). To improve the physical stability upon lyophilization, an addition of P407 of 1% w/v prevented aggregation, increased physical stability, and maintained chemical stability of the lyophilized powders of diazepam-loaded polymeric micelles for 3 months storage at 4°C. The rate and amount of diazepam release from TPGS polymeric micelles mainly depended on the concentration of TPGS. The release data were fitted to Higuchi's model suggesting that the drug release mechanism was controlled by Fickian diffusion. In conclusion, 10% w/v TPGS and 1% w/v P407 were the optimum formulation of lyophilized diazepam-loaded polymeric micelles.