Drug-Loaded Lipid-Core Micelles in Mucoadhesive Films as a Novel Dosage Form for Buccal Administration of Poorly Water-Soluble and Biological Drugs

Rheological insights into 3D printing of drug products: Drug nanocrystal-poloxamer gels for semisolid extrusion

The importance of ink rheology to the outcome of 3D printing is well recognized. However, rheological properties of printing inks containing drug nanocrystals have not been widely investigated. Therefore, the objective of this study was to establish a correlation between the composition of nanocrystal printing ink, the ink rheology, and the entire printing process. Indomethacin was used as a model poorly soluble drug to produce nanosuspensions with improved solubility properties through particle size reduction. The nanosuspensions were further developed into semisolid extrusion 3D printing inks with varying nanocrystal and poloxamer 407 concentrations. Nanocrystals were found to affect the rheological properties of the printing inks both by being less self-supporting and having higher yielding resistances. During printing, nozzle blockages occurred. Nevertheless, all inks were found to be printable. Finally, the rheological properties of the inks were successfully correlated with various printing and product properties. Overall, these experiments shed new light on the rheological properties of printing inks containing nanocrystals.

Inkjet Printing of Pharmaceuticals

Inkjet printing (IJP) is an additive manufacturing process that selectively deposits ink materials, layer-by-layer, to create 3D objects or 2D patterns with precise control over their structure and composition. This technology has emerged as an attractive and versatile approach to address the ever-evolving demands of personalized medicine in the healthcare industry. Although originally developed for nonhealthcare applications, IJP harnesses the potential of pharma-inks, which are meticulously formulated inks containing drugs and pharmaceutical excipients. Delving into the formulation and components of pharma-inks, the key to precise and adaptable material deposition enabled by IJP is unraveled. The review extends its focus to substrate materials, including paper, films, foams, lenses, and 3D-printed materials, showcasing their diverse advantages, while exploring a wide spectrum of therapeutic applications. Additionally, the potential benefits of hardware and software improvements, along with artificial intelligence integration, are discussed to enhance IJP's precision and efficiency. Embracing these advancements, IJP holds immense potential to reshape traditional medicine manufacturing processes, ushering in an era of medical precision. However, further exploration and optimization are needed to fully utilize IJP's healthcare capabilities. As researchers push the boundaries of IJP, the vision of patient-specific treatment is on the horizon of becoming a tangible reality.

Development of Simvastatin-Loaded Particles Using Spray Drying Method for Ex Tempore Preparation of Cartridges for 2D Printing Technology

In this work, a spray drying method was developed to produce drug/polymer (simvastatin/polycaprolactone) microparticles that have the potential to be used as a pre-formulation for ex tempore preparation of 2D printing cartridges. An experimental model was designed with the process parameters set to predict the smallest particle size required for successful 2D printing. Three different types of particles (lactose, nanocellulose/lactose, calcium silicate) were produced, and the average size of the dry particles varied depending on the sampling location (cyclone, collection vessel). The encapsulation efficiency of simvastatin was highest with nanocellulose/lactose from the collection vessel. The one-month stability of simvastatin in the particles showed low content, but the addition of ascorbic acid as an antioxidant increased the chemical stability of the drug. Interestingly, the addition of antioxidants decreased the stability of simvastatin in the calcium silicate particles from the collection vessel. Dispersion of the particles in three different propylene glycol and water mixtures (10/90, 50/50, and 90/10% (v/v)), representing a printable ink medium with three different viscosity and surface tension properties, showed that nanocellulose/lactose was the most suitable antiadhesive in terms of dispersed particle size (˂1 µm). After one month of storage, the dispersed particles remained in the same size range without undesirable particle agglomeration.

Advances in buccal and oral delivery of insulin

Diabetes mellitus is a metabolic endocrine disease characterized by chronic hyperglycemia with disturbances in metabolic processes, such as those related to carbohydrates, fat, and protein. There are two main types of this disease: type 1 diabetes (T1D) and type 2 diabetes (T2D). Insulin therapy is pivotal to the management of diabetes. Over the last two decades, many routes of administration, including nasal, pulmonary, rectal, transdermal, buccal, and ocular, have been investigated. Nevertheless, subcutaneous parenteral administration is still the most common route for insulin therapy. To overcome poor bioavailability and the barriers to oral insulin absorption, novel approaches in the field of oral drug delivery and administration have been brought about by the coalescence of different branches of nanoscience and nanotechnology, such as nanomedicine, nano-biochemistry, and nano-pharmacy. Novel drug delivery systems, including nanoparticles, nano-platforms, and nanocarriers, have been suggested. The objective of this review is to provide an update on the various promising approaches that have been explored and evaluated for the safe and efficient oral and buccal administration of insulin.

A Micro-Configured Multiparticulate Reconstitutable Suspension Powder of Fixed Dose Rifampicin and Pyrazinamide: Optimal Fabrication and In Vitro Quality Evaluation

The scarcity of age-appropriate pharmaceutical formulations is one of the major challenges impeding successful management of tuberculosis (TB) prevalence in minors. To this end, we designed and assessed the quality of a multiparticulate reconstitutable suspension powder containing fixed dose rifampicin and pyrazinamide (150 mg/300 mg per 5 mL) which was prepared employing solid−liquid direct dispersion coupled with timed dehydration, and mechanical pulverization. The optimized formulation had a high production yield (96.000 ± 3.270%), displayed noteworthy powder flow quality (9.670 ± 1.150°), upon reconstitution the suspension flow property was non-Newtonian and was easily redispersible with gentle manual agitation (1.720 ± 0.011 strokes/second). Effective drug loading was attained for both pyrazinamide (97.230 ± 2.570%w/w) and rifampicin (97.610 ± 0.020%w/w) and drug release followed a zero-order kinetic model (R2 = 0.990) for both drugs. Microscopic examinations confirmed drug encapsulation efficiency and showed that the particulates were micro-dimensional in nature (n < 700.000 µm). The formulation was physicochemically stable with no chemically irreversible drug-excipient interactions based on the results of characterization experiments performed. Findings from organoleptic evaluations generated an overall rating of 4.000 ± 0.000 for its attractive appearance and colour 5.000 ± 0.000 confirming its excellent taste and extremely pleasant smell. Preliminary cytotoxicity studies showed a cell viability above 70.000% which indicates that the FDC formulation was biocompatible. The optimized formulation was environmentally stable either as a dry powder or reconstituted suspension. Accordingly, a stable and palatable FDC antimycobacterial reconstitutable oral suspension powder, intended for flexible dosing in children and adolescents, was optimally fabricated.

Structural Characterization and Optimization of a Miconazole Oral Gel

The development of semisolid formulations, gels in particular, has raised the attention of scientists more and more over the last decades. Because of their biocompatibility, hydrophilic nature, and capacity of absorbing large quantities of water, hydrogels are still one of the most promising pharmaceutical formulations in the pharmaceutical industry. The purpose of this study is to develop an optimal formulation capable of incorporating a water-poorly soluble active ingredient such as miconazole used in the treatment of fungal infections with Candida albicans and Candida parapsilosis. A D-optimal design was applied to study the relationship between the formulation parameter and the gel characteristics. The independent parameters used in this study were the Carbopol 940 concentration (the polymer used to obtain the gel matrix), the sodium hydroxide amount, and the presence/absence of miconazole. Ten different dependent parameters (Y1-Y10) were evaluated (penetrometry, spreadability, viscosity, and tangential tension at 1 and 11 levels of speed whilst destructuring and during the reorganization of the gel matrix). The consistency of the gels ranged from 23.2 mm (GO2) to 29.6 mm (GM5). The least spreadable gel was GO7 (1384 mm²), whilst the gel that presented the best spreadability was GO1 (3525 mm²). The viscosity and the tangential stress at the selected levels (1 and 11) varied due to the different compositions of the proposed gels. The gels were also tested for drug content and antifungal activity. All determinations had satisfying results; the drug content was within limits accepted by Ph. Eur. 10 and all formulations containing miconazole exhibited antifungal activity. An optimal formulation with miconazole was attained, consisting of 0.84% Carbopol 940 and 0.32% sodium hydroxide.

Irinotecan-Loaded Polymeric Micelles as a Promising Alternative to Enhance Antitumor Efficacy in Colorectal Cancer Therapy

Colorectal cancer has been considered a worldwide public health problem since current treatments are often ineffective. Irinotecan is a frontline chemotherapeutic agent that has dose-limiting side effects that compromise its therapeutic potential. Therefore, it is necessary to develop a novel, targeted drug delivery system with high therapeutic efficacy and an improved safety profile. Here, micellar formulations composed of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000] (DSPE-mPEG_2k) containing irinotecan were proposed as a strategy for colorectal cancer therapy. Firstly, the irinotecan-loaded micelles were prepared using the solvent evaporation method. Then, micelles were characterized in terms of size, polydispersity, zeta potential, entrapment efficiency, and release kinetics. Cytotoxicity and in vivo antitumor activity were evaluated. The micelles showed size around 13 nm, zeta potential near neutral (-0.5 mV), and encapsulation efficiency around 68.5% (irinotecan 3 mg/mL) with a sustained drug release within the first 8 h. The micelles were evaluated in a CT26 tumor animal model showing inhibition of tumor growth (89%) higher than free drug (68.7%). Body weight variation, hemolytic activity, hematological, and biochemical data showed that, at the dose of 7.5 mg/kg, the irinotecan-loaded micelles have low toxicity. In summary, our findings provide evidence that DSPE-mPEG_2k micelles could be considered potential carriers for future irinotecan delivery and their possible therapeutic application against colorectal cancer.

Chitosan - Polyphosphate nanoparticles for a targeted drug release at the absorption membrane

The aim of this study was to develop nanoparticles (NPs) providing a targeted drug release directly on the epithelium of the intestinal mucosa. NPs were prepared via ionic gelation between cationic chitosan (Cs) and anionic polyphosphate (PP). The resulting NPs were characterized by their size, polydispersity index (PDI) and zeta potential. Isolated and cell-associated intestinal alkaline phosphatase (IAP) was employed to trigger polyphosphate cleavage in Cs-PP NPs which was quantified via malachite green assay. In parallel, the shift in zeta potential was determined. In-vitro drug release studies were performed in Franz diffusion cells with Cs-PP NPs containing rhodamine 123 as model active ingredient. Furthermore, cytotoxicity of Cs-PP NPs was assessed via resazurin assay on Caco-2 cells as well as via hemolysis assay on red blood cells. Cs-PP NPs exhibited an average size of 144.17 ± 10.95 nm and zeta potential of -12.6 ± 0.50 mV. The encapsulation efficiency of rhodamine 123 by Cs-PP NPs was 86.8%. After incubation with isolated IAP for 3 h the polyphosphate of Cs-PP NPs was cleaved to monophosphate and zeta potential raised up to -2.3 ± 0.30 mV. Cs-PP NPs showed a non-toxic profile. Within 3 h, 62.0 ± 10.8% and 14.1 ± 2.2% of total rhodamine 123 was released from Cs-PP NPs upon incubation with isolated as well as porcine intestine derived intestinal alkaline phosphatase (IAP), respectively. According to these results, Cs-PP NPs are promising drug delivery systems to enable a drug targeted release at the absorption membrane.

Preparation and Characterization of a Novel Mucoadhesive Carvedilol Nanosponge: A Promising Platform for Buccal Anti-Hypertensive Delivery

Carvedilol (CRV) is a non-selective third generation beta-blocker used to treat hypertension, congestive heart failure and angina pectoris. Oral administration of CRV showed poor bioavailability (25%), which might be ascribed to its extensive first-pass metabolism. Buccal delivery is known to boost drugs bioavailability. The aim of this study is to investigate the efficacy of bilosomes-based mucoadhesive carvedilol nanosponge for enhancing the oral bioavailability of CRV. The bilosomes were prepared, optimized and characterized for particle size, surface morphology, encapsulation efficiency and ex-vivo permeation studies. Then, the optimized formula was incorporated into a carboxymethyl cellulose/hydroxypropyl cellulose (CMC/HPC) composite mixture to obtain buccal nanosponge enriched with CRV bilosomes. The optimized bilosome formula (BLS9), showing minimum vesicle size, maximum entrapment, and highest cumulative in vitro release, exhibited a spherical shape with 217.2 nm in diameter, 87.13% entrapment efficiency, and sustained drug release for up to 24 h. In addition, ex-vivo drug permeation across sheep buccal mucosa revealed enhanced drug permeation with bilosomal formulations, compared to aqueous drug suspension. Consecutively, BLS9 was incorporated in a CMC/HPC gel and lyophilized for 24 h to obtain bilosomal nanosponge to enhance CRV buccal delivery. Morphological analysis of the prepared nanosponge revealed improved swelling with a porosity of 67.58%. The in vivo assessment of rats indicated that CRV-loaded nanosponge efficiently enhanced systolic/diastolic blood pressure, decreased elevated oxidative stress, improved lipid profile and exhibited a potent cardio-protective effect. Collectively, bilosomal nanosponge might represent a plausible nanovehicle for buccal delivery of CRV for effective management of hypertension.

Inkjet printing of small molecules, biologics, and nanoparticles

During the last decades, inkjet printing has emerged as a novel technology and attracted the attention of the pharmaceutical industry, as a potential method for manufacturing personalized and customizable dosage forms to deliver drugs. Commonly, the desired drug is dissolved or dispersed within the ink and then dispensed in various dosage forms. Using this approach, several studies have been conducted to load hydrophilic or poorly water-soluble small molecules onto the surface of different solid substrates, including films, tablets, microneedles, and smart data-enriched edible pharmaceuticals, using two-dimensional and three-dimensional inkjet printing methods, with high dose accuracy and reproducibility. Furthermore, biological drugs, such as peptides, proteins, growth factors, and plasmids, have also been evaluated with positive results, eliciting the expected biological response; nonetheless, minor changes in the structure of these compounds with significant impaired activity cannot be dismissed. Another strategy using inkjet printing is to disperse drug-loaded nanoscale particles in the ink liquid, such as nanosuspension, nanocomplexes, or nanoparticles, which have been explored with promising results. Although these favorable outcomes, the proper selection of ink constituents and the inkjet printer, the correlation of printing cycles and effectively printed doses, the stability studies of drugs within the ink and the optimal analysis of samples before and after the printing process are the main challenges for inkjet printing, and therefore, this review analyzes these aspects to assess the body of current literature and help to guide future investigations on this field.