In this study, we investigated how the formation and properties of Pickering emulsions (PEs) stabilized by zein/tannic acid particles (ZTAPs) are impacted by the method used to generate the particles, before or during emulsification. ZTAPs were obtained through two antisolvent precipitation methods (sequential and co-precipitation) across zein/tannic acid molar ratio (R) range of 1/0 to 1/30. Emulsions were prepared using four methods, either with pre-formed ZTAPs or by mixing zein and tannic acid immediately before or during emulsification. The results indicated that pre-forming the particles prior to emulsification is crucial for controlling droplet size and homogeneity, while the quantity of tannic acid plays a supporting role. Tannic acid is not only critical for emulsion stabilization but also imparts its antioxidant activity to the emulsions. This activity is also controlled by the molar ratio R of the particles and the preparation protocol. ZTAPs are promising plant-based stabilizers for emulsions in the food and pharmaceutical industries. These findings provide a better understanding of the importance of their method of production in controlling the characteristics (droplet size, stability, and antioxidant properties) of the emulsions they stabilize.

The development of alginate microparticles for encapsulation of hydrophilic drug is addressed. The alginate microparticles are produced by the emulsification/gelation process. The objective of this study is to optimize the encapsulation of sunset yellow, a model of small hydrophilic drug, by the means of an agile quality by design (QbD) approach. Five input factors are considered: the alginate concentration (2-7% w/V), the drug/polymer ratio (0.1/1-0.5/1), the cross-linker addition flow rate (1-1.6mL/min), the cross-linker volume (5-10mL), and the crosslinking time (15-60min). Critical quality attributes (and their associated specifications) are the particle size (∈30;150µm) and polydispersity, the encapsulation efficiency (>50%), and the drug loading (>10%). The implemented agile method follows three successive QbD sprints, each based on a specific design of experiments (DoE). First, a screening of the process parameters is performed using a Plackett-Burman design, followed in a second sprint by the implementation of a central composite Hartley’s design to identify the design space and to extract four eligible control operating regions where the probability to meet the CQA specifications is above 95%. In the last sprint, one of these optimal operating conditions has been qualified by testing eight end points of the region through the application of a full factorial design. This operating region corresponds to a combination of three factors: alginate concentration in [6.7;7]%, drug/polymer ratio in [0.29;0.34]w/w and a curing time in [40;60]min.

The encapsulation of active ingredients is an important process in various industrial sectors including pharmaceutics, foods and cosmetics. For the first time, the capacity of non-conventional anti-Bancroft oil-in-water Pickering emulsions stabilized by partially hydrophobized silica to encapsulate an apolar active is addressed. A dispersed phase volume of paraffin oil of 50% coupled to 0.5 wt.% of silica has been employed to avoid excess of silica in the continuous phase and encapsulate higher amount of ibuprofen (the model drug). Three ibuprofen contents ranging from 100 mg (1.6 mg/mL of paraffin) to 420 mg (6 mg/mL of paraffin) have been tested. The encapsulation efficiency as well as the emulsions properties are investigated by the means of light diffusion, microscopy, rheology, and HPLC coupled to mass balance. The Pickering emulsion is very efficient for the encapsulation of ibuprofen with encapsulation rates of 99% obtained inside droplets of 30 µm for all the 3 ibuprofen concentrations. This encapsulation ability is perfectly maintained, whether during ageing (during 90 days), or when the emulsion is diluted by a factor 100 inside physiological media at basic and acidic pH.

Introduction: A serious game was implemented and evaluated to consolidate the knowledge of third-year pharmacy students about drug vectorisation systems. Methods: After a lecture on nanotechnology in health, students were immersed in a magical world for the one-and-a-half-hour tutorial: to complete their mission, they had to pick the right cards and solve puzzles within a limited time. Then, in debriefing, all the key concepts were recalled and explained according to their metaphorical counterparts, i.e. the puzzles. Feedback from the beta-test in 2021 (n=112) helped to optimise the pitch, the game, the rules and the debriefing. A formative evaluation was performed in 2022 (n=140) investigating students’ perception immediately after the session and immediate knowledge retention using a pre-test/post-test evaluation. The results of the final assessment were considered indirect indicators of student involvement. Results: Although the game itself did not immediately improve the students’ knowledge retention, it really was a great tool to motivate and engage participants, which might explain a significant improvement in the final assessment. Conclusion: A serious game can be an interesting tool to teach pharmaceutical technology. To help colleagues wishing to revitalise their pharmacy interventions, a non-exhaustive list of ideas to consider before starting the game conception is provided.

Osteoarthritis (OA) is the most common degenerative joint disease. Rapamycin is a potential candidate for OA treatment by increasing the autophagy process implicated in its physiopathology. To optimize Rapamycin profit and avoid systemic side effects, intra-articular (i.a.) administration appeared helpful. However, Rapamycin's highly hydrophobic nature and low bioavailability made it challenging to develop purpose-made drug delivery systems to overcome these limitations. We developed Rapamycin-loaded nanoparticles (NPs) using poly (lactic-co-glycolic acid) by emulsion/evaporation method. We evaluated these NPs' cytocompatibility towards cartilage (chondrocytes) and synovial membrane cells (synoviocytes) for a potential i.a. administration. The in vitro characterization of Rapamycin-loaded NPs had shown a suitable profile for an i.a. administration. In vitro biocompatibility of NPs was highlighted to 10 µM of Rapamycin for both synoviocytes and chondrocytes, but significant toxicity was observed with higher concentrations. Besides, synoviocytes are more sensitive to Rapamycin-loaded NPs than chondrocytes. Finally, we observed in vitro that an adapted formulated Rapamycin-loaded NPs could be safe at suitable i.a. injection concentrations. The toxic effect of Rapamycin encapsulated in these NPs on both articular cells was dose-dependent. After Rapamycin-loaded NPs i.a. administration, local retention, in situ safety, and systemic release should be evaluated with experimental in vivo models.

Lipid nanocapsules (LNCs) are drug delivery platforms designed for different administration routes including intravenous delivery. Nanocarrier binding with plasma proteins such as albumin is an important factor that influences the pharmacokinetics of the drug and the drug delivery system. The aim of this paper was to characterize LNCs with different surface compositions and hydrophobicities to study their interactions with albumin: binary LNCs [oil-glyceryl trioctanoate (TG) and PEGylated surfactant macrogol 15-hydroxystearate (MHS)] and ternary LNCs (TG, MHS, and Span 80). Span was found to stabilize and decrease the LNC size. The formation of a stable LNC/albumin complex in the ground state was demonstrated. Thermodynamic parameters indicated that complex formation was exothermic and spontaneous, and the interactions involved van der Waals forces and hydrogen bond formation. Ternary LNCs showed higher affinity for albumin than did binary LNCs (affinity constant 10-fold higher). This study is the first report on the thermodynamic mechanisms that lead to the formation of a complex between albumin and organic nanoparticles with different surface architectures.

Nitric oxide (NO) deficiency is often associated with several acute and chronic diseases. NO donors and especially S-nitrosothiols such as S-nitrosoglutathione (GSNO) have been identified as promising therapeutic agents. Although their permeability through the intestinal barrier have recently be proved, suitable drug delivery systems have to be designed for their oral administration. This is especially challenging due to the physico-chemical features of these drugs: high hydrophilicity and high lability. In this paper, three types of particles were prepared with an Eudragit® polymer: nanoparticles and microparticles obtained with a water-in-oil-in-water emulsion/evaporation process versus microparticles obtained with a solid-in-oil-in-water emulsion/evaporation process. They had a similar encapsulation efficiency (around 30%), and could be freeze-dried then be stored at least one month without modification of their critical attributes (size and GSNO content). However, microparticles had a slightly slower in vitro release of GSNO than nanoparticles, and were able to boost by a factor of two the drug intestinal permeability (Caco-2 model). Altogether, this study brings new data about GSNO intestinal permeability and three ready-to-use formulations suitable for further preclinical studies with oral administration.

Endothelial dysfunction predisposing to cardiovascular diseases is defined as an imbalance in the production of vasodilating factors, such as nitric oxide (NO), and vasoconstrictive factors. To insure its physiological role, NO, a radical with very short half-life, requires to be stored and transported to its action site. S-nitrosothiols (RSNOs) like S-nitrosoglutathione (GSNO) represent the main form of NO storage within the vasculature. The NO store formed by RSNOs is still bioavailable to trigger vasorelaxation. In this way, RSNOs are an emerging class of NO donors with a potential to restore NO bioavailability within cardiovascular disorders. The aim of this study was to compare S-nitrosothiols ability, formed of peptide (glutathione) like the physiologic GSNO or derived from amino acids (cysteine, valine) like the synthetics S-nitroso-N-acetylcysteine (NACNO) and S-nitroso-N-acetylpenicillamine (SNAP), respectively, to produce a vascular store of NO either in endothelium-intact or endothelium-removed aortae in order to evaluate whether RSNOs can be used as therapeutics to compensate endothelial dysfunction. Sodium nitroprusside (SNP), a marketed drug already in clinics, was used as a non-RSNO NO-donor. Endothelium-intact or endothelium-removed aortae, isolated from normotensive Wistar rats, were exposed to RSNOs or SNP. Then, NO-derived (NOx) species, representing the NO store inside the vascular wall, were quantified using the diaminonaphthalene probe coupled to mercuric ions. The bioavailability of the NO store and its ability to induce vasodilation was tested using N-acetylcysteine, then its ability to counteract vasoconstriction was challenged using phenylephrine (PHE). All the studied RSNOs were able to generate a NO store materialized by a three to five times increase in NOx species inside aortae. NACNO was the most potent RSNO to produce a vascular NO store bioavailable for vasorelaxation and the most efficient to induce vascular hyporeactivity to PHE in endothelium-removed aortae. GSNO and SNAP were equivalent and more efficient than SNP. In endothelium-intact aortae, the NO store was also formed whereas it seemed less available for vasorelaxation and did not influence PHE-induced vasoconstriction. In conclusion, RSNOs - NACNO in a better extent - are able to restore NO bioavailability as a functional NO store within the vessel wall, especially when the endothelium is removed. This was associated with a hyporeactivity to the vasoconstrictive agent phenylephrine. Treatment with RSNOs could present a benefit to restore NO-dependent functions in pathological states associated with injured endothelium.

Cardiovascular diseases are associated with oxidative stress and a reduced bioavailability of nitric oxide (NO). To counteract both processes, the administration of S-nitrosoglutathione (GSNO) can be envisaged. GSNO is able to induce protein S-nitrosation (Pr-SNO), which is a post-translational modification of proteins, participating in the storage of NO in tissues, and protect thiol functions from oxidation. However, GSNO antioxidant power is poorly studied, which is probably linked to its low stability. This low stability can be addressed by nanotechnologies that will increase GSNO protection and provide a sustained release of the drug.

As a physiological nitric oxide donor, S-nitrosoglutathione (GSNO) is a promising candidate for several diseases (e.g., stroke and atherosclerosis). However, its clinical application has been limited by its low stability. In order to protect GSNO suitable for oral route administration and to achieve sustained release, 3 different particles from nano-size to micro-size were obtained by a water-in-oil-in-water (W/O/W) or solid-in-oil-in-water (S/O/W) double emulsion/solvent evaporation method. The 3 different particles tuned out to have similar encapsulation efficiency while the microparticles showed longer release time. Finally, the 3 formulations have been successfully lyophilized for long term stability.

S-Nitrosothiols, a class of NO donors, demonstrate potential benefits for cardiovascular diseases. Drugs for such chronic diseases require long term administration preferentially through the oral route. However, the absorption of S-nitrosothiols by the intestine, which is the first limiting barrier for their vascular bioavailability, is rarely evaluated. Using an in vitro model of intestinal barrier, based on human cells, the present work aimed at elucidating the mechanisms of intestinal transport (passive or active, paracellular or transcellular pathway) and at predicting the absorption site of three S-nitrosothiols: S-nitrosoglutathione (GSNO), S-nitroso-N-acetyl-l-cysteine (NACNO) and S-nitroso-N-acetyl-d-penicillamine (SNAP). These S-nitrosothiols include different skeletons carrying the nitroso group, which confer different physico-chemical characteristics and biological activities (antioxidant and anti-inflammatory). According to the values of apparent permeability coefficient, the three S-nitrosothiols belong to the medium class of permeability. The evaluation of the bidirectional apparent permeability demonstrated a passive diffusion of the three S-nitrosothiols. GSNO and NACNO preferentially cross the intestinal barrier though the transcellular pathway, while SNAP followed both the trans- and paracellular pathways. Finally, the permeability of NACNO was favoured at pH 6.4, which is close to the pH of the jejunal part of the intestine. Through this study, we determined the absorption mechanisms of S-nitrosothiols and postulated that they can be administrated through the oral route.

Which scientist has never heard of glutathione (GSH)? This well-known low-molecular-weight tripeptide is perhaps the most famous natural antioxidant. However, the interest in GSH should not be restricted to its redox properties. This multidisciplinary review aims to bring out some lesser-known aspects of GSH, for example, as an emerging tool in nanotechnologies to achieve targeted drug delivery. After recalling the biochemistry of GSH, including its metabolism pathways and redox properties, its involvement in cellular redox homeostasis and signaling is described. Analytical methods for the dosage and localization of GSH or glutathiolated proteins are also covered. Finally, the various therapeutic strategies to replenish GSH stocks are discussed, in parallel with its use as an addressing molecule in drug delivery.

Effective treatment of critical-size defects is a key challenge in restorative surgery of bone. The strategy covers the implantation of biocompatible, osteoconductive, bioactive and biodegradable devices which (1) well interact with native tissue, mimic multi-dimensional and hierarchical structure of bone and (2) are able to enhance bone repair, treating post implantation pathologies or bone diseases by local delivery of therapeutic agents. Among different options, calcium phosphate biomaterials are found to be attractive choices, due to their excellent biocompatibility, customisable bioactivity and biodegradability. Several approaches have been established to enhance this material ability to be loaded with a therapeutic agent, in order to obtain an in situ controlled release that meets the clinical needs. This article reviews the most important factors influencing on both drug loading and release capacity of porous calcium phosphate bone substitutes. Characteristics of the carrier, drug/carrier interactions, experimental conditions of drug loading and evaluation of drug delivery are considered successively.

The LR12 peptide has been reported to reduce the size of infarct and improve both cardiac function and survival in myocardial infarction in murine models, after daily repeated intraperitoneal injections. In order to protect peptide from degrading and to prolong its release, in situ implants based on biocompatible biodegradable polymers were prepared and both in vitro and in vivo releases were evaluated after subcutaneous administration to Wistar rats. A progressive and complete release was obtained in vitro in 3 weeks. In vivo, a 7-day sustained release was demonstrated after administrating the formulation once; bioavailability was improved by protecting the peptide against the degradation identified as a dimerization through disulfide bond formation. As a conclusion, in situ forming formulations are a suitable alternative for the therapeutic use of this peptide.

A simple, sensitive, selective and robust HPLC method based on intrinsic fluorescence detection was developed for the quantitation of a dodecapeptide (designated as LR12), inhibitor of Triggering Receptor Expressed on Myeloid cells-1, in rat whole blood. Sample treatment was optimized using protein precipitation and solid-phase extraction. Chromatographic separation was carried out in a gradient mode using a core-shell C18 column (150 × 4.6 mm, 3.6 μm) with mobile phases of acetonitrile and water containing trifluoroacetic acid at 1.0 mL/min. The method was validated using methodology described by the US Food and Drug Administration guidelines for bioanalytical methods. Linearity was demonstrated within the 50-500 ng/mL range and the lower limit of quantitation was 50 ng/mL. Finally, a preliminary pharmacokinetic study after intraperitoneal injection of LR12 in rats was conducted to evaluate both LR12 monomer and its corresponding disulfide dimer, the main product of degradation. Beyond the fact that this paper describes the first fully validated method for LR12 analysis in blood samples, the approach followed here to optimize pre-analytical steps could be beneficial to develop HPLC and/or MS methods for other pharmaceutical peptides.