Development and Evaluation of Cocoa Butter Taste Masked Ibuprofen Using Supercritical Carbon Dioxide

Taste-masking methods in multiparticulate dosage forms with a focus on poorly soluble drugs

In the past, the administration of medicines for children mainly involved changes to adult dosage forms, such as crushing tablets or opening capsules. However, these methods often led to inconsistent dosing, resulting in under- or overdosing. To address this problem and promote adherence, numerous initiatives, and regulatory frameworks have been developed to develop more child-friendly dosage forms. In recent years, multiparticulate dosage forms such as mini-tablets, pellets, and granules have gained popularity. However, a major challenge that persists is effectively masking the bitter taste of drugs in such formulations. This review therefore provides a brief overview of the current state of the art in taste masking techniques, with a particular focus on taste masking by film coating. Methods for evaluating the effectiveness of taste masking are also discussed and commented on. Another important issue that arises frequently in this area is achieving sufficient dissolution of poorly water-soluble drugs. Since the simultaneous combination of sufficient dissolution and taste masking is particularly challenging, the second objective of this review is to provide a critical summary of studies dealing with multiparticulate formulations that are tackling both of these issues.

Solvent-free method for masking the bitter taste of azithromycin dihydrate using supercritical fluid technology

INTRODUCTION AND PURPOSE

The unpleasant extremely bitter taste of the orally administered broad-spectrum antibiotic azithromycin decreases patient compliance, especially in pediatrics. This issue can be overcome by decreasing drug interaction with the tasting buds using insoluble polymers at salivary pH (6.8 - 7.4), like the cationic polymer Eudragit EPO. Supercritical fluid technology is a green synthesis method for preparing pharmaceutical preparations that replace organic solvents with safe supercritical CO2. This study aimed to mask the bitter taste of azithromycin using the supercritical fluid method and a pH-sensitive Eudragit EPO polymer.

METHODS

A foaming process was investigated for preparing a formulation (TEST), which comprises treating the polymer with supercritical carbon dioxide (CO2) fluid to prepare a taste-masked dosage form without employing organic solvents or flavors.

RESULTS

The use of the supercritical technique at 40 °C and 10 MPa for 2 h allowed the manufacturing of solvent-free polymeric foam with azithromycin dispersions; the average calculated percentage of apparent volume change was 62.5 ± 5.9% with an average pore diameter of 34.879 Å. The formulated sample showed low drug release in simulated salivary fluid while keeping its crystalline nature. Moreover, clinical studies on healthy subjects showed that the formula successfully masked azithromycin's bitter taste.

CONCLUSIONS

Overall, it has been shown herein that the supercritical fluid technology foaming method is promising in masking the bitter taste of bitter ingredients.

In Vitro and In Vivo Evaluation of Dark Chocolate as Age-appropriate Oral Matrix

Swallowing difficulties encountered by geriatric patients who undergo polypharmacy represent a significant challenge that hampers patient compliance and therapeutic management. As an appealing and sensory-pleasing, chocolate-based formulations have emerged as a potential alternative oral dosage form suitable for both the elderly and paediatric populations. However, the extent to which the incorporation of drugs into a chocolate matrix affects their oral availability remains unclear. Therefore, the objective of this investigation was to explore the in vitro and in vivo performance of an ibuprofen-based chocolate dosage form. A matrix based on dark chocolate and the model drug was prepared at two distinct temperatures: 50 and 80 °C. In vitro release studies revealed that ibuprofen formulated through co-melting at 80 °C exhibited a statistically significant slower drug release (p < 0.05) compared to formulations prepared at 50 °C in both FaSSGF (fasted-state simulated gastric fluid) and lipolysis media. The enzymatic degradation of chocolate in the presence of lipase accelerated in vitro ibuprofen release from chocolate matrices. To delve deeper into the bioavailability of ibuprofen within the chocolate formulations, we conducted an in vivo assessment, comparing the pharmacokinetic profiles of ibuprofen in its conventional suspension form with our chocolate-based dosage forms. A notable drop (p < 0.05) in the maximum serum concentration of ibuprofen when incorporated into co-melted or solid-suspension chocolate matrices. However, no significant differences in plasma exposure were observed between the two formulations. These findings shed a light on the potential of chocolate to extend of ibuprofen when integrated into various chocolate matrices, showcasing the potential held by these innovative formulations.

Potential use of red hibiscus flower extract for the production of spray-chilled microparticles: Characterization, stability, and bioaccessibility in vitro of anthocyanins

Microparticles (MLP) containing red hibiscus flower (Hibiscus rosa-sinensis) anthocyanins were produced by spray chilling, and characterized for physicochemical parameters, accelerated stability, and gastrointestinal release profile. Fully hydrogenated palm oil and cocoa butter were used as wall materials, at a lipid blend to hibiscus extract ratio of 70:30 (w/w). The lipid blends containing fully hydrogenated palm oil (FHPO) and cocoa butter (CB) were produced by ultrasound-assisted technique in the following FHPO to CB ratios: 100:0 (Control), 75:25, 50:50, 60:40, and 40:60. Increasing the cocoa butter content reduced the melting temperature and increased the unstable polymorphic behavior of the microparticles, resulting in amorphous characteristics. The microparticles exhibited higher viscosity, more agglomerates, and holes on the surface, and greater diameters. Characteristic peaks corresponding to the hibiscus extract were observed in the infrared spectra of the spray-chilled microparticles, indicating that the microencapsulation did not affect the anthocyanins. The antioxidant capacity of the red hibiscus anthocyanins ranged from 75 % to 79 %, with the best result observed for the treatment MLP_75:25. Higher antioxidant activities were observed for the lipid blends containing lower cocoa butter concentrations. Concerning the release profile of anthocyanins, the simulated GI digestion in vitro showed reduced release in the gastric tract and more intense release in the intestinal tract for an effective absorption of the antioxidant compounds in the small intestine. Furthermore, the treatment MLP_75:25 showed the highest encapsulation retention and lower total color difference in the accelerated stability study. Overall, the microparticles from all treatments were light-sensitive and thermosensitive at 35 °C. Thus, it is recommended to store the particles in a dark environment at temperatures below 35 °C for an effective use of the microparticles as natural food colorants.

The In Vitro, In Vivo, and PBPK Evaluation of a Novel Lung-Targeted Cardiac-Safe Hydroxychloroquine Inhalation Aerogel

Hydroxychloroquine (HCQ) was repurposed for COVID-19 treatment. Subtherapeutic HCQ lung levels and cardiac toxicity of oral HCQ were overcome by intratracheal (IT) administration of lower HCQ doses. The crosslinker-free supercritical fluid technology (SFT) produces aerogels and impregnates them with drugs in their amorphous form with efficient controlled release. Mechanistic physiologically based pharmacokinetic (PBPK) modeling can predict the lung's epithelial lining fluid (ELF) drug levels. This study aimed to develop a novel HCQ SFT formulation for IT administration to achieve maximal ELF levels and minimal cardiac toxicity. HCQ SFT formulation was prepared and evaluated for physicochemical, in vitro release, pharmacokinetics, and cardiac toxicity. Finally, the rat HCQ ELF concentrations were predicted using PBPK modeling. HCQ was amorphous after loading into the chitosan-alginate nanoporous microparticles (22.7±7.6 μm). The formulation showed a zero-order release, with only 40% released over 30 min compared to 94% for raw HCQ. The formulation had a tapped density of 0.28 g/cm3 and a loading efficiency of 35.3±1.3%. The IT administration of SFT HCQ at 1 mg/kg resulted in 23.7-fold higher bioavailability, fourfold longer MRT, and eightfold faster absorption but lower CK-MB and LDH levels than oral raw HCQ at 4 mg/kg. The PBPK model predicted 6 h of therapeutic ELF levels for IT SFT HCQ and a 100-fold higher ELF-to-heart concentration ratio than oral HCQ. Our findings support the feasibility of lung-targeted and more effective SFT HCQ IT administration for COVID-19 compared to oral HCQ with less cardiac toxicity. Graphical abstract.

Orodispersible Films with Rupatadine Fumarate Enclosed in Ethylcellulose Microparticles as Drug Delivery Platform with Taste-Masking Effect

Orally disintegrating (orodispersible) films provide a versatile tool for drug administration, especially in the pediatric and geriatric population, since they reduce the risk of choking and do not necessitate drinking water during application. By considering their direct contact with the taste buds, palatability is an influential aspect related to patient compliance. The microparticles based on taste-masking polymers containing drugs enclosed inside effectively mask the unpleasant taste of medicines. Ethylcellulose is a hydrophobic polymer widely used as a taste-masking material. Rupatadine fumarate, a second-generation antihistamine drug, is characterised by an intense bitter taste; therefore, it is crucial to achieve a tolerable taste whilst developing orodispersible formulations with its content. The objective of this study was to develop orally disintegrating films with rupatadine fumarate in the form of ethylcellulose-based microparticles obtained from aqueous dispersions of ethylcellulose—Surelease^® or Aquacoat^® ECD. It was a technological challenge to achieve homogenous drug content per dosage unit and sufficient mechanical properties for film operating due to the necessity to suspend the microparticles in the casting solution. Although the process of obtaining films consisted of several steps (mixing, pouring, drying), the particles were homogeneously dispersed, and each film of the desired size contained the proper dose of the drug. The taste-masking effect was also maintained. This parameter was confirmed by three independent methods: in vivo by healthy volunteers, an electronic tongue and a dissolution test. The applied taste-evaluation techniques showed that the films containing Aquacoat^® ECD microparticles have the highest degree of bitter taste reduction, which confirms the results obtained in our previous studies.

An overview on the application of supercritical carbon dioxide for the processing of pharmaceuticals

Supercritical carbon dioxide (scCO2) application in the pharmaceutical industry is still undeveloped regardless of significant research interests in this processing medium shown in the last decades. ScCO2 technologies can improve drug solubility, bioavailability, and therapeutic effect. These technologies can lead to the development of new formulations that will contribute to a decrease in drug dose, medication frequency, and increase patients' well-being. Considering the significant decrease in the price of high-pressure equipment and society's growing need for cleaner production and safer products, it is expected that symbiosis between supercritical fluid and pharmaceutical technologies will happen soon. Therefore, this review was focused on the latest contributions of scCO2 technologies to the pharmaceutical field. The main aim was to bring these technologies closer to pharmaceutical specialists. For this purpose, the most commonly used technologies were explained and discussed: the preparation of solid dispersions, polymer impregnation with drugs, and drug micro/nanoparticle production using scCO2.

Supercritical CO2 Extraction of Organic Solvents from Flunisolide and Fluticasone Propionate

In this work, Class 2 and Class 3 solvents contained in two corticosteroids, flunisolide (Fluni) and fluticasone propionate (Fluti), were reduced to a few ppm by supercritical CO₂ extraction. The process was carried out at pressures from 80 to 200 bar, temperatures of 40 °C and 80 °C, and at a fixed CO₂ flow rate of 0.7 kg/h. The results demonstrated that CO₂ density is the key parameter influencing the extraction kinetics and the solvent final residue. In particular, in the range investigated, optimal pressure and temperature conditions for the extraction of residual organic solvents were found working at 200 bar and 40 °C, which corresponds to a CO₂ density of 0.840 g/cm³. Operating in this way, total organic solvent residues were reduced from 13,671 ppm and 326 ppm to 12 ppm and 10 ppm for Fluni and Fluti, respectively.