Recent Advances in Nanodrug Delivery Systems Production, Efficacy, Safety, and Toxicity.

In the last three decades, the development of nanoparticles or nano-formulations as drug delivery systems has emerged as a promising tool to overcome the limitations of conventional delivery, potentially to improve the stability and solubility of active molecules, promote their transport across the biological membranes, and prolong circulation times to increase efficacy of a therapy. Despite several nano-formulations having applications in drug delivery, some issues concerning their safety and toxicity are still debated. This chapter describes the recent available information regarding safety, toxicity, and efficacy of nano-formulations for drug delivery. Several key factors can influence the behavior of nanoparticles in a biological environment, and their evaluation is crucial to design non-toxic and effective nano-formulations. Among them, we have focused our attention on materials and methods for their preparation (including the innovative microfluidic technique), mechanisms of interactions with biological systems, purification of nanoparticles, manufacture impurities, and nano-stability. This chapter places emphasis on the utilization of in silico, in vitro, and in vivo models for the assessment and prediction of toxicity associated with these nano-formulations. Furthermore, the chapter includes specific examples of in vitro and in vivo studies conducted on nanoparticles, illustrating their application in this field.

Multistimuli responsive microcapsules produced by the prilling/vibration technique for targeted colonic delivery of probiotics.

This study aimed to microencapsulate the probiotic strain Lactiplantibacillus plantarum 4S6R (basonym Lactobacillus plantarum) in both microcapsules and microspheres by prilling/vibration technique. A specific polymeric mixture, selected for its responsiveness to parallel colonic stimuli, was individuated as a carrier of microparticles. Although the microspheres were consistent with some critical quality parameters, they showed a low encapsulation efficiency and were discarded. The microcapsules produced demonstrated high yields (97.52%) and encapsulation efficiencies (90.06%), with dimensional analysis and SEM studies confirming the desired size morphology and structure. The results of thermal stress tests indicate the ability of the microcapsules to protect the probiotic. Stability studies showed a significant advantage of the microcapsules over non-encapsulated probiotics, with greater stability over time. The release study under simulated gastrointestinal conditions demonstrated the ability of the microcapsules to protect the probiotics from gastric acid and bile salts, ensuring their viability. Examination in a simulated faecal medium revealed the ability of the microcapsules to release the bacteria into the colon, enhancing their beneficial impact on gut health. This research suggests that the selected mixture of reactive polymers holds promise for improving the survival and efficacy of probiotics in the gastrointestinal tract, paving the way for the development of advanced probiotic products.

Harnessing therapeutic deep eutectic solvents in self-emulsifying systems to improve CBD delivery.

In this study, Cannabidiol crystals (CBD) were used as a BCS class II model drug to generate a novel therapeutic deep eutectic solvent (THEDES) with easy preparation using caprylic acid (CA). The hydrogen bonding interaction was confirmed by different techniques such as FT-IR and NMR, resulting in a hydrophobic system suitable for liquid formulations. The CBD-based THEDES, combined with a specific mixture of surfactants and co-surfactants, successfully formed a self-emulsifying drug delivery system (SEDDS) that generated uniform nano-sized droplets once dispersed in water. Hence, the THEDES showed compatibility with the self-emulsifying approach, offering an alternative method to load drugs at their therapeutic dosage. Physical stability concerns regarding the unconventional oily phase were addressed through stress tests using multiple and dynamic light scattering, demonstrating the robustness of the system. In addition, the formulated SEDDS proved effective in protecting CBD from the harsh acidic gastric environment for up to 2 h at pH 1.2. Furthermore, in vitro studies have confirmed the safety of the formulation and the ability of CBD to permeate Caco-2 cells when formulated. This investigation highlights the potential incorporation of THEDES in lipid-based formulations like SEDDS, expanding the avenues for innovative oral drug delivery approaches.

Mucoadhesive Budesonide Solution for the Treatment of Pediatric Eosinophilic Esophagitis.

Eosinophilic Esophagitis is an antigen-mediated inflammatory disease characterized by thickening of the esophageal wall, leading to dysphagia, vomiting, reflux, and abdominal pain. This disease can be treated with a therapeutic approach ranging from diet to pharmacological therapy. Jorveza® (budesonide) and Dupixent® (dupilumab) are treatments for Eosinophilic Esophagitis approved by the European Medicines Agency in adults but not in children. Budesonide-based extemporaneous oral liquid suspensions could be prepared for pediatric use. The main limit of this formulation is that budesonide needs a longer residence time on the esophageal mucosa to solubilize and diffuse in it to exert its local anti-inflammatory effect. Herein, we propose the development of an extemporaneous mucoadhesive oral budesonide solution for the pediatric population. A liquid vehicle containing hydroxypropyl-beta-cyclodextrin as a complexing agent and carboxymethylcellulose sodium as a mucoadhesive excipient was used to prepare budesonide-based formulations. A stable solution at a concentration of 0.7 mg/mL was successfully prepared and characterized. The formulation showed rheological and mucoadhesive properties suitable for an Eosinophilic Esophagitis local prolonged treatment. In this way, pharmacists can prepare stable budesonide-based mucoadhesive solutions, providing both patients and physicians with a new therapeutic option for Eosinophilic Esophagitis pediatric treatment.

Hydrophilic Ready-to-use Vehicles and Compounded Topical Medications.

Pharmaceutical compounding has a crucial role for the health of patients, allowing the preparation of formulation out of market or for a personalized therapy. This study is aimed to conduct a screening of possible ready-to-use hydrophilic vehicles for the preparation of topical dosage forms. Incorporation tests of several active pharmaceutical ingredients were performed, and the physical stability of the extemporaneous formulations was assessed by performing an accelerated centrifuge test. The results showed that it was possible to realize several physically stable topical medications without using special equipment or instruments, guaranteeing a fast and repeatable preparation process. The goal of this work is to provide compounding pharmacists a table that summarizes some of the possible vehicles that can be used for the formulation of topical treatments.

Physical-chemical Stability of the Extemporaneous Paracetamol Oral Suspension in Puccini Base.

This study describes a new method for the preparation of extemporaneous paracetamol-based suspensions for pediatric and adult patients. This method allows the preparation of extemporaneous suspensions up to concentrations of 50 mg/mL by using a liquid base, named "Puccini". A high-pressure liquid chromatographic method was developed and validated for the determination of chemical stability of paracetamol when the formulations were stored at 4°C and 25°C. The chemical stability of the active pharmaceutical ingredient in the base was demonstrated for more than 90 days. Visual analyses of the formulations showed a phenomenon of precipitation at both storage temperatures, but the simple agitation of the formulations before its use re-established the formation of homogeneous suspensions.

Lipophilic Ready-to-use Vehicles and Compounded Topical Medications.

The preparation of formulations that are not currently on the market or prepared for customized therapy is possible by pharmaceutical compounding. In this study, incorporation tests of some active pharmaceutical ingredients in five ready-touse lipophilic semisolid vehicles were performed, and the physical stability of the prepared extemporaneous formulations was assessed by performing an accelerated centrifuge test. The results demonstrated that it was possible to formulate physically stable topical medications without using special equipment or instruments, ensuring a fast, efficient, and repeatable preparation process. The objective of this work was to provide to compounding pharmacists a table that summarizes some of the semisolid lipophilic vehicles, such as creams water/oil, and ointments, that can be used for the formulation of topical treatments.

Chitosan and Anionic Solubility Enhancer Sulfobutylether-ß-Cyclodextrin-Based Nanoparticles as Dexamethasone Ophthalmic Delivery System for Anti-Inflammatory Therapy.

Cataract surgery interventions are constantly increasing, particularly among adult and elderly patients. This type of surgery can lead to inflammatory states of the ocular anterior segment (AS), usually healed via postoperative treatment with dexamethasone (DEX)-containing eye drops. The application of eye drops is challenging due to the high number of daily administrations. In this study, mucoadhesive nanoparticles (NPs) were formulated to improve the residence time of DEX on the corneal mucosa, enhancing the drug's solubility and bioavailability. The NPs were generated using an ionotropic gelation technique, exploiting the interaction between the cationic group of chitosan (CS) and the anionic group of sulfobutylether-ß-cyclodextrin (SBE-ß-CD). The formation of the inclusion complex and its stoichiometry were studied through phase solubility studies, Job's plot method, and Bi-directional transport studies on MDCKII-MDR1. The obtained NPs showed good chemical and physical characteristics suitable for drug loading and subsequent testing on animal mucosa. The DEX-loaded CS/SBE-ß-CD NPs exhibited a prolonged residence time on animal mucosa and demonstrated enhanced drug permeability through the corneal membrane, showing a sustained release profile. The developed NPs posed no irritation or toxicity concerns upon local administration, making them an optimal and innovative drug delivery system for inflammatory AS diseases treatment.

Extemporaneous Topical Minoxidil Solutions for the Treatment of Androgenetic Alopecia- Stability Studies and Incorporation Tests of Active Pharmaceutical Ingredients in Aloplus Total Base.

Minoxidil is one of the most employed active pharmaceutical ingredients for the  treatment of androgenetic alopecia. The authors propose a new method for production of minoxidil lotions using Aloplus Total. The latter is a propylene glycol-free liquid base in which the presence of hydroxypropyl-ß-cyclodextrin and ethanol allows the solubilization of high drug amounts. Minoxidil intrinsic solubility in the base was determined, and a comprehensive chemical and physical stability study was conducted on 8% w/w minoxidil lotions. Incorporation tests of different active pharmaceutical ingredients that can be combined to 5% w/w minoxidil were also carried out. The analyses showed that minoxidil intrinsic solubility in the new base was 85.93 mg/mL ± 4.17 mg/mL (8.64% w/w ± 0.42% w/w) at 25°C, and the topical lotions were found to be physically and chemically stable for more than 180 days when stored at 25°C or 40°C. Incorporation tests of several active pharmaceutical ingredients also were successful, indicating that Aloplus Total is a liquid vehicle also useful for the preparation of minoxidil-based topical lotions for a synergistic treatment of androgenetic alopecia.

Investigating the prilling/vibration technique to produce gastric-directed drug delivery systems for misoprostol.

Prilling/vibration technique to produce oral microcapsules was explored to achieve local delivery of misoprostol (MIS), a prostaglandin E1 analogue indicated for the treatment of gastric-duodenal ulcers, at the gastric mucosa. To improve MIS chemical stability and reduce its associated systemic side effects, drug delivery systems were designed and developed as microcapsules consisting of a core of sunflower oil and MIS (Fs6 and Fs14) or a MIS complex with hydroxypropyl-beta-cyclodextrin (HP-ß-CD) (Fs18), confirmed by specific studies, and a polymeric shell. The produced microcapsules showed high encapsulation efficiencies for those with MIS solubilized in sunflower oil (>59.86 %) and for the microcapsules with MIS/HP-ß-CD (97.61 %). To demonstrate the ability of these systems to deliver MIS into the stomach, swelling and drug release experiments were also conducted in simulated gastric fluid. Among the three formulations, FS18 showed gastric release within 30 min and was the most advantageous formulation because the presence of the MIS/HP-ß-CD inclusion complex ensured a greater ability to stabilise MIS in the simulated gastric environment. In addition, these new systems have a small size (<540 µm), and good flow properties and the dose of the drug could be easily adapted using different amounts of microcapsules (flexibility), making them a passepartout for different age population groups.

Cyclodextrin-based supramolecular deep eutectic solvent (CycloDES): A vehicle for the delivery of poorly soluble drugs.

The aim of this work was to develop a new class of deep eutectic solvent (DES) composed of a complexation agent, namely hydroxy-propyl-ß-cyclodextrin (HPßCD), to exploit a synergic solubilization-enhancing approach. For this purpose, cyclodextrin-based supramolecular DES (CycloDES) were physical-chemical characterized and loaded with three different BCS class II model drugs, specifically Cannabidiol, Indomethacin, and Dexamethasone, evaluating the influence of different factors on the observed solubility and permeation compared with the only HPßCD/drug complexation. Hence, CycloDESs were presented as a possible vehicle for drugs and represent a novel potential approach for solving BCS class II and IV solubility issues, demonstrating at least a 100-fold improvement in the investigated drug solubilities. Furthermore, CycloDESs demonstrated a significantly improved resistance to dilution preserving a high percentage of drug in solution (i.e. 93% for Indomethacin) when water is added to the DES if compared with a glucose-choline chloride DES, used as a standard. This evidence guarantees the solubility-enhancing effect useful for the delivery of BCS class II and IV drugs converting solid raw material to advantageous liquid vehicles bypassing the rate-determining dissolution step.

3D printed mucoadhesive orodispersible films manufactured by direct powder extrusion for personalized clobetasol propionate based paediatric therapies.

The aim of this work is the development and production by Direct Powder Extrusion (DPE) 3D printing technique of novel oral mucoadhesive films delivering Clobetasol propionate (CBS), useful in paediatric treatment of Oral Lichen Planus (OLP), a rare chronic disease. The DPE 3D printing of these dosage forms can allow the reduction of frequency regimen, the therapy personalization, and reduction of oral cavity administration discomfort. To obtain suitable mucoadhesive films, different polymeric materials, namely hydroxypropylmethylcellulose or polyethylene oxide blended with chitosan (CS), were tested and hydroxypropyl-ß-cyclodextrin was added to increase the CBS solubility. The formulations were tested in terms of mechanical, physico-chemical, and in vitro biopharmaceutical properties. The film showed a tenacious structure, with drug chemical-physical characteristics enhancement due to its partial amorphization during the printing stage and owing to cyclodextrins multicomponent complex formation. The presence of CS enhanced the mucoadhesive properties leading to a significant increase of drug exposure time on the mucosa. Finally, the printed films permeation and retention studies through porcine mucosae showed a marked retention of the drug inside the epithelium, avoiding drug systemic absorption. Therefore, DPE-printed films could represent a suitable technique for the preparation of mucoadhesive film potentially usable for paediatric therapy including OLP.

Stability of Omeprazole Extemporaneous Oral Solution in Chopin Base.

Omeprazole is the progenitor of proton pump inhibitors. It is used for the treatment of ulcer and gastroesophageal reflux in dosages ranging from 10 mg/day to 40 mg/day, calibrated according to the patient's age and body weight. In this study, the authors provide a report on the preparation of an extemporaneous liquid formulation of omeprazole using fast oral solution Chopin a hydroxypropyl-?-cyclodextrin liquid base (pH 8 to 9) that is able to solubilize the drug. A solubility study of the drug in the liquid vehicle and a physical-chemical stability study of the 1-mg/mL formulation at 4°C and 25°C were performed. Analyses were carried out by using a high-pressure liquid chromatographic analytical method. Results showed that the intrinsic solubility of the drug in Chopin base was 5.33 mg/mL ± 0.23 mg/mL at 25°C and that omeprazole was chemically stable when the formulation was stored at 4°C over a period of 3 months, while its shelf life at 25°C was only 9 days. This study has demonstrated that the resulting liquid formulation is suitable for all patients, in particular children or adults who are unable to take other pharmaceutical dosage forms, which overcomes the limitations of the medicines currently available on the market.

Extemporaneous Topical Minoxidil Solutions for the Treatment of Alopecia: Stability Studies and Incorporation Tests of Active Ingredients in ALOPLUS FAST Base.

Minoxidil is a vasodilator drug generally employed for the treatment of various forms of alopecia. In this article, the authors propose an alternative to the formulation reported in the British Pharmacopoeia for the realization of topical minoxidil -based solutions using ALOPLUS FAST. This liquid vehicle is an ethanol- and propylene glycol-free base which allows the complete solubilization of minoxidil, thanks to the presence of hydroxypropyl-ß-cyclodextrin. Solubility and chemical stability studies of the active ingredient in the formulation at a concentration of 5% w/w and physical stability studies of this extemporaneous preparation are reported. Incorporation tests of various active pharmaceutical ingredients that can be combined with minoxidil for alopecia synergic treatment have been carried out. Analyses were performed by using a high-pressure liquid chromatography analytical method. The results showed that the intrinsic solubility of the drug in the liquid base was 62.37 mg/mL ± 0.85 mg/mL (5.24 w/w ± 0.07% w/w) at 25°C; minoxidil was chemically stable in ALOPLUS FAST; and the formulation was physically stable for more than six months, under different storage conditions. Incorporation tests of several active pharmaceutical ingredients in 2% to 4% w/w minoxidil formulations were successful as well.

Digital Technologies Applied to Control the One-Step Process of Cannabis Olive Oil Preparations.

The reproducibility of an extemporaneous preparation is an essential condition for guaranteeing the quality, efficacy, and safety of the medicinal product. This study aimed to develop a controlled one-step process for cannabis olive oil preparations by applying digital technologies. For this purpose, the chemical profile of cannabinoid contents in oil extracts of Bedrocan, FM2, and Pedanios varieties obtained with the already in use method, proposed by the Italian Society of Compounding Pharmacists (SIFAP), was compared with two new methods, specifically the Tolotto Gear® extraction method (TGE) and the Tolotto Gear® extraction method preceded by a pre-extraction procedure (TGE-PE). HPLC analyses showed that the concentration of THC using cannabis flos with a high THC content (over 20% w/w) was always higher than 21 mg/mL for the Bedrocan variety and close to 20 mg/mL for the Pedanios variety when applying TGE, while with TGE-PE, the THC concentration was higher than 23 mg/mL for the Bedrocan variety. For the FM2 variety, the amounts of THC and CBD in the oil formulations obtained using TGE were higher than 7 mg/mL and 10 mg/mL, respectively, and for TGE-PE, the concentrations of THC and CBD were higher than 7 mg/mL and 12 mg/mL, respectively. GC-MS analyses were performed to define the terpene contents in the oil extracts. The samples of Bedrocan flos extracted with TGE-PE displayed a distinctive profile, highly rich in terpenes and devoid of oxidized volatile products. Thus, TGE and TGE-PE allowed performing a quantitative extraction of cannabinoids and increasing the total mono-di-tri terpenes and sesquiterpene concentrations. The methods were repeatable and applicable to any quantity of raw material, preserving the phytocomplex of the plant.

Direct cyclodextrin based powder extrusion 3D printing of budesonide loaded mini-tablets for the treatment of eosinophilic colitis in paediatric patients.

The purpose of this study was to combine direct powder extrusion (DPE) 3D printing and fluid bed coating techniques to create a budesonide (BD) loaded solid oral formulations for the treatment of eosinophilic colitis (EC) in paediatric patients. The preferred medication for EC treatment is BD, which has drawbacks due to its poor water solubility and low absorption. Additionally, since commercially available medications for EC treatment are created and approved for adult patients, administering them to children sometimes requires an off-label use and an impromptu handling, which can result in therapeutic ineffectiveness. The DPE 3D approach was investigated to create Mini-Tablets (MTs) to suit the swallowing, palatability, and dose flexibility control requirements needed by paediatric patients. Additionally, DPE 3D and the inclusion of hydroxypropyl-ß-cyclodextrin in the initial powder mixture allowed for an improvement in the solubility and rate of BD dissolution in aqueous medium. Then, to accomplish a site-specific drug release at the intestinal level, MTs were coated with a layer of Eudragit FS 30D, an enteric polymer responsive at pH > 7.0 values. In vitro release experiments showed that film-coated MTs were suitable in terms of size and dose, enabling potential therapeutic customization and targeted delivery of BD to the colon.

Colonic budesonide delivery by multistimuli alginate/Eudragit® FS 30D/inulin-based microspheres as a paediatric formulation.

The purpose of this study was to develop an oral paediatric formulation of budesonide (BUD) for the treatment of inflammatory bowel disease. A formulation realized as microspheres using the prilling/vibration technique is proposed as an innovative drug delivery system ensuring BUD-specific colonic release in response to different triggers, such as pH, transit time, and resident microbiota. BUD, or the inclusion complex BUD/hydroxypropyl-ß-cyclodextrin, was loaded into microspheres consisting of different ratios of alginate, Eudragit® FS 30D, with or without inulin. Sixteen formulations are produced that show high yields and encapsulation efficiencies, ensuring a homogenous distribution of BUD into the matrix. Microsphere diameters of <655 µm and promising flow properties make these systems suitable for oral administration to children. Swelling and drug release studies in simulated gastrointestinal fluid are used to demonstrate the response of microspheres to time and pH triggers. Studies in faecal medium highlight that drug release from microspheres with inulin is also influenced by microbiota.

Chitosan/sulfobutylether-ß-cyclodextrin based nanoparticles coated with thiolated hyaluronic acid for indomethacin ophthalmic delivery.

Indomethacin (IND) is topically administered for the treatment of the anterior segment diseases such as conjunctivitis, uveitis, and inflammation prevention for post-cataract surgery, as well as posterior segment diseases as macular edema. Currently IND is available as 0.1% w/v hydroxypropyl-ß-cyclodextrin-based eye drop formulation and its bioavailability is limited by several drawbacks such as the nasolacrimal duct draining, the reflex blinking and the low volume of the conjunctival sac. In this study, chitosan (CS)/sulfobutylether-ß-cyclodextrin (SBE-ß-CD) based nanoparticles (NPs) with a mean diameter of 340 (±7) nm, a ζ-potential value of +18.3 (±0.5) mV and coated with thiolated low molecular weight hyaluronic acid were formulated to improve both the solubility and the residential time in the conjunctival sac of the loaded drug IND. The NPs were prepared through the ionotropic gelation technique, exploiting the interaction between the positively charged amino group of CS and the negatively charged sulfonic group of SBE-ß-CD. The mucoadhesive properties of the NPs were evaluated on chicken trachea and esophagus tissues using a texture analyser. The irritability effects of NPs were disclaimed with Hecam test. The developed coated NPs showed increased residential time in the conjunctival sac, displayed no irritancy or toxicity for local administration, making them an optimal and innovative drug delivery system for the treatment of anterior segment inflammation diseases. On the other hand, the uncoated NPs displayed better permeating properties since they are smaller and could be further exploited for the treatment of posterior segment diseases.

In Vivo Investigation of (2-Hydroxypropyl)-ß-cyclodextrin-Based Formulation of Spironolactone in Aqueous Solution for Paediatric Use.

Spironolactone (SPL), a potent anti-aldosterone steroidal drug used to treat several diseases in paediatric patients (e.g., hypertension, primary aldosteronism, Bartter's syndrome, and congestive heart failure), is not available in child-friendly dosage forms, and spironolactone liquids have been reported to be unpalatable. Aiming to enhance SPL solubility in aqueous solution and overcome palatability, herein, the effects of (2-hydroxypropyl)-ß-cyclodextrin (HP-ß-CyD) were thoroughly investigated on solubilisation in water and on masking the unpleasant taste of SPL in vivo. Although the complexation of SPL with HP-ß-CyD was demonstrated through phase solubility studies, Job's plot, NMR and computational docking studies, our in vivo tests did not show significant effects on taste aversion. Our findings, on the one hand, suggest that the formation of an inclusion complex of SPL with HP-ß-CyD itself is not necessarily a good indicator for an acceptable degree of palatability, whereas, on the other hand, they constitute the basis for investigating other cyclodextrin-based formulations of the poorly water-soluble steroidal drug, including solid dosage forms, such as spray-dried powders and orodispersible tablets.

Direct cyclodextrin-based powder extrusion 3D printing for one-step production of the BCS class II model drug niclosamide.

Niclosamide (NCS) is a drug that has been used as an anthelmintic and anti-parasitic drug for about 40 years. Recently, some studies have highlighted its potential in treating various tumors, allowing a repositioning of this drug. Despite its potential, NCS is a Biopharmaceutical Classification System (BCS) Class II drug and is consequently characterized by low aqueous solubility, poor dissolution rate and reduced bioavailability, which limits its applicability. In this work, we utilize a very novel technique, direct powder extrusion (DPE) 3D printing, which overcomes the limitations of previously used techniques (fused deposition modelling, FDM) to achieve direct extrusion of powder mixtures consisting of NCS, hydroxypropyl methylcellulose (HPMC, Affinisol 15 LV), hydroxypropyl-ß-cyclodextrin (HP-ß-CD) and polyethylene glycol (PEG) 6000. For the first time, direct printing of powder blends containing HP-ß-CD was conducted. For all tablets, in vitro dissolution studies showed sustained drug release over 48 h, but for tablets containing HP-ß-CD, the release was faster. Solid-state characterization studies showed that during extrusion, the drug lost its crystal structure and was evenly distributed within the polymer matrix. All printed tablets have exhibited good mechanical and physical features and a stability of the drug content for up to 3 months. This innovative printing technique has demonstrated the possibility to produce personalized pharmaceutical forms directly from powders, avoiding the use of filament used by FDM.