Lyophilized sponges loaded with curcumin solid lipid nanoparticles for buccal delivery: Development and characterization

Biopolymer Drug Delivery Systems for Oromucosal Application: Recent Trends in Pharmaceutical R&D

Oromucosal drug delivery, both local and transmucosal (buccal), is an effective alternative to traditional oral and parenteral dosage forms because it increases drug bioavailability and reduces systemic drug toxicity. The oral mucosa has a good blood supply, which ensures that drug molecules enter the systemic circulation directly, avoiding drug metabolism during the first passage through the liver. At the same time, the mucosa has a number of barriers, including mucus, epithelium, enzymes, and immunocompetent cells, that are designed to prevent the entry of foreign substances into the body, which also complicates the absorption of drugs. The development of oromucosal drug delivery systems based on mucoadhesive biopolymers and their derivatives (especially thiolated and catecholated derivatives) is a promising strategy for the pharmaceutical development of safe and effective dosage forms. Solid, semi-solid and liquid pharmaceutical formulations based on biopolymers have several advantageous properties, such as prolonged residence time on the mucosa due to high mucoadhesion, unidirectional and modified drug release capabilities, and enhanced drug permeability. Biopolymers are non-toxic, biocompatible, biodegradable and may possess intrinsic bioactivity. A rational approach to the design of oromucosal delivery systems requires an understanding of both the anatomy/physiology of the oral mucosa and the physicochemical and biopharmaceutical properties of the drug molecule/biopolymer, as presented in this review. This review summarizes the advances in the pharmaceutical development of mucoadhesive oromucosal dosage forms (e.g., patches, buccal tablets, and hydrogel systems), including nanotechnology-based biopolymer nanoparticle delivery systems (e.g., solid lipid particles, liposomes, biopolymer polyelectrolyte particles, hybrid nanoparticles, etc.).

Preparation and evaluation of vaginal suppo-sponges loaded with benzydamine, in-vitro/in-vivo study

This study aimed to design a new Benzydamine HCl (BNZ) suppo-sponge for controlled, mucoadhesive dosage form for vaginal candidiasis treatment, offering advantages over traditional creams, ointments, or gels. BNZ-loaded suppo-sponges were fabricated by simple casting / freeze-drying technique utilizing the cross-linking of chitosan (Cs) with vanillin (V). Vaginal suppo-sponges were prepared based on different vanillin cross-linking ratios (V).n), from 0 to 2%w/w. To best of our knowledge, this is the first study that uses Schiff's base between chitosan and vanillin as a drug delivery system to treat fungal vaginal infections. Schiff's base formation was confirmed by FT-IR. In-vitro appraisal showed acceptable physical and mechanical characteristics. Formulations based on cross-linking of Cs with V showed a more pronounced in-vitro antifungal activity. In-vitro drug release revealed a prolonged release pattern, becoming more noticeable with the higher cross-linked suppo-sponges (22.34% after 8 h). In-vivo testing of CsV2 suppo-sponge indicated a more pronounced reduction in fungal count than both CsV0 and Tantum® Rosa in the first week, with a peak reduction on day 7 and the 10th and 11th days of the second week. Conclusively, Chitosan/vanillin suppo-sponges represent a promising delivery system for drugs intended for local treatment of vaginal candidiasis. than both CsV0 and Tantum® Rosa in the first week, with a peak reduction on day 7 and the 10th and 11th days of the second week. Conclusively, Chitosan/vanillin suppo-sponges represent a promising delivery system for drugs intended for local treatment of vaginal candidiasis.

Novel tetrahydrocurcumin integrated mucoadhesive nanocomposite κ-carrageenan/xanthan gum sponges: a strategy for effective local treatment of oral cancerous and precancerous lesions

Oral cancer is one of the leading causes of death worldwide. Oral precancerous lesions (OPL) are the precursors of oral cancer, with varying degrees of progression. Tetrahydrocurcumin (THC) is a major metabolite of curcumin with superior anticancer properties against various types of cancer. However, THC's clinical outcome is limited by its poor aqueous solubility. Herein, we developed novel mucoadhesive biopolymer-based composite sponges for buccal delivery of THC, exploiting nanotechnology and mucoadhesion for efficient prevention and treatment of oral cancer. Firstly, THC-nanocrystals (THC-NC) were formulated and characterized for subsequent loading into mucoadhesive composite sponges. The anticancer activity of THC-NC was assessed on a human tongue squamous carcinoma cell line (SCC-4). Finally, the chemopreventive activity of THC-NC loaded sponges (THC-NC-S) was examined in DMBA-induced hamster OPL. The selected THC-NC exhibited a particle size of 532.68 ± 13.20 nm and a zeta potential of -46.08 ± 1.12 mV. Moreover, THC-NC enhanced the anticancer effect against SCC-4 with an IC50 value of 80 µg/mL. THC-NC-S exhibited good mucoadhesion properties (0.24 ± 0.02 N) with sustained drug release, where 90% of THC was released over 4 days. Furthermore, THC-NC-S had a magnificent potential for maintaining high chemopreventive activity, as demonstrated by significant regression in the dysplasia degree and a decline in cyclin D1 (control: 40.4 ± 12.5, THC-NC-S: 12.07 ± 5.2), culminating in significant amelioration after 25 days of treatment. Conclusively, novel THC-NC-S represent a promising platform for local therapy of OPL, preventing their malignant transformation into cancer.

Current appraises of therapeutic applications of nanocurcumin: A novel drug delivery approach for biomaterials in dentistry

Curcumin is a natural herb and polyphenol that is obtained from the medicinal plant Curcuma longa. It's anti-bacterial, anti-inflammatory, anti-cancer, anti-mutagenic, antioxidant and antifungal properties can be leveraged to treat a myriad of oral and systemic diseases. However, natural curcumin has weak solubility, limited bioavailability and undergoes rapid degradation, which severely limits its therapeutic potential. To overcome these drawbacks, nanocurcumin (nCur) formulations have been developed for improved biomaterial delivery and enhanced treatment outcomes. This novel biomaterial holds tremendous promise for the treatment of various oral diseases, the majority of which are caused by dental biofilm. These include dental caries, periodontal disease, root canal infection and peri-implant diseases, as well as other non-biofilm mediated oral diseases such as oral cancer and oral lichen planus. A number of in-vitro studies have demonstrated the antibacterial efficacy of nCur in various formulations against common oral pathogens such as S. mutans, P. gingivalis and E. faecalis, which are strongly associated with dental caries, periodontitis and root canal infection, respectively. In addition, some clinical studies were suggestive of the notion that nCur can indeed enhance the clinical outcomes of oral diseases such as periodontitis and oral lichen planus, but the level of evidence was very low due to the small number of studies and the methodological limitations of the available studies. The versatility of nCur to treat a diverse range of oral diseases augurs well for its future in dentistry, as reflected by rapid pace in which studies pertaining to this topic are published in the scientific literature. In order to keep abreast of the latest development of nCur in dentistry, this narrative review was undertaken. The aim of this narrative review is to provide a contemporaneous update of the chemistry, properties, mechanism of action, and scientific evidence behind the usage of nCur in dentistry.

Dual receptor specific nanoparticles targeting EGFR and PD-L1 for enhanced delivery of docetaxel in cancer therapy

Dual-receptor targeted (DRT) nanoparticles which contain two distinct targeting agents may exhibit higher cell selectivity, cellular uptake, and cytotoxicity toward cancer cells than single-ligand targeted nanoparticle systems without additional functionality. The purpose of this study is to prepare DRT poly(lactic-co-glycolic acid) (PLGA) nanoparticles for targeting the delivery of docetaxel (DTX) to the EGFR and PD-L1 receptor positive cancer cells such as human glioblastoma multiform (U87-MG) and human non-small cell lung cancer (A549) cell lines. Anti-EGFR and anti-PD-L1 antibody were decorated on DTX loaded PLGA nanoparticles to prepare DRT-DTX-PLGA via. single emulsion solvent evaporation method. Physicochemical characterizations of DRT-DTX-PLGA, such as particle size, zeta-potential, morphology, and in vitro DTX release were also evaluated. The average particle size of DRT-DTX-PLGA was 124.2 ± 1.1 nm with spherical and smooth morphology. In the cellular uptake study, the DRT-DTX-PLGA endocytosed by the U87-MG and A549 cells was single ligand targeting nanoparticle. From the in vitro cell cytotoxicity, and apoptosis studies, we reported that DRT-DTX-PLGA exhibited high cytotoxicity and enhanced the apoptotic cell compared to the single ligand-targeted nanoparticle. The dual receptor mediated endocytosis of DRT-DTX-PLGA showed a high binding affinity effect that leads to high intracellular DTX concentration and exhibited high cytotoxic properties. Thus, DRT nanoparticles have the potential to improve cancer therapy by providing selectivity over single-ligand-targeted nanoparticles.

Novel mucoadhesive celecoxib-loaded cubosomal sponges: Anticancer potential and regulation of myeloid-derived suppressor cells in oral squamous cell carcinoma

Oral squamous-cell carcinoma (OSCC) is a widespread health problem. Myeloid-derived suppressor cells (MDSCs) are major tumor microenvironment (TME) population that govern many carcinogenesis aspects by establishing immunosuppressive milieu favoring tumor aggressiveness and treatment resistance. Cyclooxygenase-2 (COX-2) regulates MDSCs activity, hence, COX-2-selective inhibition by celecoxib (CXB) showed good anticancer effect at relatively high doses with possible subsequent cardiovascular complications. Therefore, targeted CXB delivery to MDSCs may represent a promising OSCC treatment strategy. Novel mucoadhesive-cubosomal buccal sponges were prepared for MDSCs targeting and were evaluated for their in-vitro quality attributes, ex-vivo mucoadhesion using buccal chicken-mucosa. Optimally-selected formulation showed considerable uptake by CD33⁺/11b⁺MDSCs in human OSCC cell-line (SCC-4) when quantitatively analyzed by flow-cytometry and examined using confocal-laser microscope. Optimum formulations loaded with low CXB doses (12 mg) were promoted to in-vivo studies via local application, using 4-nitroquinoline-1-oxide-induced OSCC in rats, and compared to their corresponding CXB gels. SP16 revealed the highest ability to decrease MDSC activation, recruitment and TME-immunosuppression in the isolated tumors. Consequently, SP16 exerted the greatest capacity to reduce histologic tumor grade, the OSCC-specific serum tumor markers levels, cancer hallmarks and stemness markers. CXB-loaded cubosomal sponges preferentially target MDSCs with noticeable anticancer potential and may exemplify novel mucoadhesive nanocarriers for OSCC treatment.

Vardenafil-Loaded Bilosomal Mucoadhesive Sponge for Buccal Delivery: Optimization, Characterization, and In Vivo Evaluation

Vardenafil (VDF) is a relatively new phosphodiesterase-5 inhibitor that has limited oral bioavailability (≈15%). The objective of this study was to develop bilosome-based mucoadhesive buccal sponge for augmenting the oral bioavailability of VDF. VDF-loaded bilosomes were fabricated and optimized using a Box-Behnken design. The optimized VDF-loaded bilosomal formulation was assessed for surface morphology, particle size, thermal characteristics, and in vitro release. Afterwards, the optimized bilosomal formulation was incorporated into a cellulose-based matrix to obtain buccal sponge, which was evaluated for ex vivo permeation studies, in vivo oral bioavailability, and in vivo serum concentration of cyclic guanosine monophosphate (cGMP). The mean particle size and entrapment efficiency (%) of optimized bilosome formulation were 282.6 ± 9.5 nm and 82.95 ± 3.5%, respectively. In vitro release studies at pH 6.8 emphasized the potential of optimized bilosomal formulation to sustain VDF release for 12 h. Ex vivo permeation study using sheep buccal mucosa indicated significant enhancement in penetration of VDF from bilosomal buccal sponge compared to plain VDF gel. Pharmacokinetic study in Albino rats showed ~5 fold increase in relative bioavailability with bilosomal buccal sponge, compared to VDF suspension. In addition, VDF-loaded bilosomal buccal sponge triggered higher serum levels of cGMP, a biomarker of VDF in vivo efficacy, compared to oral VDF suspension. To sum up, bilosomes might represent a potential nanocarrier for buccal delivery of VDF, enhancing its oral bioavailability and therapeutic efficacy.

Recent advances in pain management based on nanoparticle technologies

BACKGROUND

Pain is a vital sense that indicates the risk of injury at a particular body part. Successful control of pain is the principal aspect in medical treatment. In recent years, the advances of nanotechnology in pain management have been remarkable. In this review, we focus on literature and published data that reveal various applications of nanotechnology in acute and chronic pain management.

METHODS

The presented content is based on information collected through pain management publications (227 articles up to April 2021) provided by Web of Science, PubMed, Scopus and Google Scholar services.

RESULTS

A comprehensive study of the articles revealed that nanotechnology-based drug delivery has provided acceptable results in pain control, limiting the side effects and increasing the efficacy of analgesic drugs. Besides the ability of nanotechnology to deliver drugs, sophisticated nanosystems have been designed to enhance imaging and diagnostics, which help in rapid diagnosis of diseases and have a significant impact on controlling pain. Furthermore, with the development of various tools, nanotechnology can accurately measure pain and use these measurements to display the efficiency of different interventions.

CONCLUSIONS

Nanotechnology has started a new era in the pain management and many promising results have been achieved in this regard. Nevertheless, there is still no substantial and adequate act of nanotechnology in this field. Therefore, efforts should be directed to broad investigations.

Surface Modification of Lipid-Based Nanoparticles

There is a growing interest in the development of lipid-based nanocarriers for multiple purposes, including the recent increase of these nanocarriers as vaccine components during the COVID-19 pandemic. The number of studies that involve the surface modification of nanocarriers to improve their performance (increase the delivery of a therapeutic to its target site with less off-site accumulation) is enormous. The present review aims to provide an overview of various methods associated with lipid nanoparticle grafting, including techniques used to separate grafted nanoparticles from unbound ligands or to characterize grafted nanoparticles. We also provide a critical perspective on the usefulness and true impact of these modifications on overcoming different biological barriers, with our prediction on what to expect in the near future in this field.

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.

Recent Advancements and Patents on Buccal Drug Delivery Systems: A Comprehensive Review

The major requirement for a dosage form to be successful is its ability to penetrate the site of application and the bioavailability of the drug released from the dosage form. The buccal drug delivery is an influential route to deliver the drug into the body. Here, in this context, various novel approaches that include lipoidal carriers like ethosomes, transferosomes, niosomes etc. and electrospun nanofibers are discussed, with respect to buccal drug delivery. These carriers can be easily incorporated into buccal dosage forms like patches and gels that are responsible for increased permeation across the buccal epithelium. The in vivo methods of evaluation on animal models are conscribed here. The novel biocarriers of lipoidal and non-lipoidal nature can be utilized by loading the drug into them, which are helpful in preventing drug degradation and other drawbacks as compared to conventional formulations. The globally patented buccal formulations give us a wide context in literature about the patents filed and granted in the recent years. When it comes to patient compliance, age is an issue, which is also solved by the buccal route. The pediatric buccal formulations are researched for the customization to be delivered to children. Diseases like mouth ulcers, oral cancer, Parkinson's disease, aphthous stomatitis etc. have been successfully treated through the buccal route, which infers that the buccal drug delivery system is an effective and emerging area for formulation and development in the field of pharmaceutics.

Orodispersible Films: A Delivery Platform for Solid Lipid Nanoparticles?

To overcome the poor bioavailability observed for many newly developed active pharmaceutical ingredients (APIs), an appropriate formulation strategy is necessary. One approach is the formulation of these substances in solid lipid nanoparticles and their further processing into solid dosage forms. A promising and innovative oral delivery platform could be orodispersible films (ODFs). ODFs were already investigated more closely, e.g., for the administration of API nanoparticles, and proved their suitability for this formulation approach. The current study was aimed at investigating if the HPMC (hydroxypropyl methyl cellulose) film matrix is also suitable to serve as an appropriate delivery platform for solid lipid nanoparticles. Dependent on the type of triglyceride nanoparticles embedded in the film matrix and the formulation of the lipid particles, lipid contents of up to 54 wt.% could be realized in the film matrix without the loss of the nanoparticulate state. Good mechanical properties were confirmed for these films by determining the tensile strength as well as the elongation before breakage. Interestingly, processing of a lipid suspension into this solid dosage form led to a significantly reduced transformation of the lipid particles from the metastable α- into the stable β-polymorph. This could prove very beneficial when the lipid particles are loaded with APIs.

Lipid-Based Drug Delivery Systems in Regenerative Medicine

The most important goal of regenerative medicine is to repair, restore, and regenerate tissues and organs that have been damaged as a result of an injury, congenital defect or disease, as well as reversing the aging process of the body by utilizing its natural healing potential. Regenerative medicine utilizes products of cell therapy, as well as biomedical or tissue engineering, and is a huge field for development. In regenerative medicine, stem cells and growth factor are mainly used; thus, innovative drug delivery technologies are being studied for improved delivery. Drug delivery systems offer the protection of therapeutic proteins and peptides against proteolytic degradation where controlled delivery is achievable. Similarly, the delivery systems in combination with stem cells offer improvement of cell survival, differentiation, and engraftment. The present review summarizes the significance of biomaterials in tissue engineering and the importance of colloidal drug delivery systems in providing cells with a local environment that enables them to proliferate and differentiate efficiently, resulting in successful tissue regeneration.

Management of recurrent aphthous ulcers exploiting polymer-based Muco-adhesive sponges: in-vitro and in-vivo evaluation

Recurrent aphthous ulcer (RAU) is a well-known painful, inflammatory disease with uncertain etiology for which local symptomatic therapy is only available. The aim of this study was to formulate and characterize muco-adhesive sponges containing a mixture of tenoxicam and miconazole nitrate to manage pain, inflammation and avoid candida infection that may accompany RAU due to poor oral hygiene. Two polymers at different concentrations were used to prepare sponges applying simple freeze-drying. Medicated chitosan (2%) sponges (mC2) showed acceptable physical appearance, surface pH (6.3 ± 0.042), porosity (25.7% ± 1.8), swelling index (5.7 ± 0.11), in-vivo and ex-vivo muco-adhesion time (115 min.±0.813 and 155 min.±1.537, respectively), ex-vivo muco-adhesion force (0.09 N ± 0.002) and scanning electron microscope (SEM) images. For concurrent clear-cut determination of tenoxicam and miconazole nitrate from mC2, a new UPLC method was developed and validated. mC2 sponges exhibited superior in-vitro drug release profiles where ∼100% of tenoxicam released within 5 min for fast pain relief with a more prolonged miconazole nitrate release. Furthermore, in-vivo animal study revealed that mC2 caused a significant decrease in the acetic acid-induced ulcer size in rats after 6 days of treatment (p < .0001) compared to negative and positive controls. Additionally, histopathological examination showed faster healing with complete restoration of the normal oral histology in rats. The present study concludes that chitosan sponge loaded with a combination of tenoxicam and miconazole nitrate could improve healing of RAU cases.

High-Payload Buccal Delivery System of Amorphous Curcumin-Chitosan Nanoparticle Complex in Hydroxypropyl Methylcellulose and Starch Films

Oral delivery of curcumin (CUR) has limited effectiveness due to CUR’s poor systemic bioavailability caused by its first-pass metabolism and low solubility. Buccal delivery of CUR nanoparticles can address the poor bioavailability issue by virtue of avoidance of first-pass metabolism and solubility enhancement afforded by CUR nanoparticles. Buccal film delivery of drug nanoparticles, nevertheless, has been limited to low drug payload. Herein, we evaluated the feasibilities of three mucoadhesive polysaccharides, i.e., hydroxypropyl methylcellulose (HPMC), starch, and hydroxypropyl starch as buccal films of amorphous CUR–chitosan nanoplex at high CUR payload. Both HPMC and starch films could accommodate high CUR payload without adverse effects on the films’ characteristics. Starch films exhibited far superior CUR release profiles at high CUR payload as the faster disintegration time of starch films lowered the precipitation propensity of the highly supersaturated CUR concentration generated by the nanoplex. Compared to unmodified starch, hydroxypropyl starch films exhibited superior CUR release, with sustained release of nearly 100% of the CUR payload in 4 h. Hydroxypropyl starch films also exhibited good payload uniformity, minimal weight/thickness variations, high folding endurance, and good long-term storage stability. The present results established hydroxypropyl starch as the suitable mucoadhesive polysaccharide for high-payload buccal film applications.

An Updated Overview of the Emerging Role of Patch and Film-Based Buccal Delivery Systems

Buccal mucosal membrane offers an attractive drug-delivery route to enhance both systemic and local therapy. This review discusses the benefits and drawbacks of buccal drug delivery, anatomical and physiological aspects of oral mucosa, and various in vitro techniques frequently used for examining buccal drug-delivery systems. The role of mucoadhesive polymers, penetration enhancers, and enzyme inhibitors to circumvent the formulation challenges particularly due to salivary renovation cycle, masticatory effect, and limited absorption area are summarized. Biocompatible mucoadhesive films and patches are favored dosage forms for buccal administration because of flexibility, comfort, lightness, acceptability, capacity to withstand mechanical stress, and customized size. Preparation methods, scale-up process and manufacturing of buccal films are briefed. Ongoing and completed clinical trials of buccal film formulations designed for systemic delivery are tabulated. Polymeric or lipid nanocarriers incorporated in buccal film to resolve potential formulation and drug-delivery issues are reviewed. Vaccine-enabled buccal films have the potential ability to produce both antibodies mediated and cell mediated immunity. Advent of novel 3D printing technologies with built-in flexibility would allow multiple drug combinations as well as compartmentalization to separate incompatible drugs. Exploring new functional excipients with potential capacity for permeation enhancement of particularly large-molecular-weight hydrophilic drugs and unstable proteins, oligonucleotides are the need of the hour for rapid advancement in the exciting field of buccal drug delivery.

Nanoparticles in Dentistry: A Comprehensive Review

In recent years, nanoparticles (NPs) have been receiving more attention in dentistry. Their advantageous physicochemical and biological properties can improve the diagnosis, prevention, and treatment of numerous oral diseases, including dental caries, periodontal diseases, pulp and periapical lesions, oral candidiasis, denture stomatitis, hyposalivation, and head, neck, and oral cancer. NPs can also enhance the mechanical and microbiological properties of dental prostheses and implants and can be used to improve drug delivery through the oral mucosa. This paper reviewed studies from 2015 to 2020 and summarized the potential applications of different types of NPs in the many fields of dentistry.

Biomimetic clotrimazole-loaded PLGA films with enhanced adhesiveness for controlled drug release

Biomimetic adhesive surfaces have a number of potential applications in the pharmaceutical and biomedical fields. Fabrication techniques must be adapted to biocompatible and biodegradable materials required for controlled drug release applications. In this study biomimetic adhesive poly(lactic-co-glycolic acid) (PLGA) films loaded with different concentrations of clotrimazole (CTZ) were prepared without combining other adhesive excipients as a controlled release system for potential local oral drug delivery. The films were fully characterized from morphological point of view, and CTZ-loaded biomimetic films exhibited adequate surface pH values, high drug encapsulation efficiency, and loading content. The adhesion strength of the obtained films was significantly higher compared to a flat film reference under different contact conditions. Thermal analysis indicated a decrease of drug crystallinity upon incorporation into PLGA films. The in vitro release of CTZ from PLGA biomimetic films was tested in simulated saliva, and it exhibited an initial burst release, accompanied by a sustained release phase over 10 days. Finally, the mucoadhesive properties of the obtained films was studied using agar/mucin plate as a representative mucosal substrate, and the results demonstrated superior mucoadhesion potential of CTZ-loaded biomimetic film in comparison to its flat counterpart. Having demonstrated the ability to load CTZ into PLGA biomimetic films with enhanced adhesion capacity, the potential use in local oral drug delivery applications warrants further in vitro and in vivo investigations.

Nanocomposite sponges for enhancing intestinal residence time following oral administration

In this work, nanocomposites that combine mucopenetrating and mucoadhesive properties in a single system are proposed as innovative strategy to increase drug residence time in the intestine following oral administration. To this aim, novel mucoadhesive chitosan (CH) sponges loaded with mucopenetrating nanoemulsions (NE) were developed via freeze-casting technique. The NE mucopenetration ability was determined studying the surface affinity and thermodynamic binding of the nanosystem with mucins. The ability of nanoparticles to penetrate across a preformed mucins layer was validated by 3D-time laps Confocal Laser Scanning Microscopy imaging. Microscopy observations (Scanning Electron Microscopy and Optical Microscopy) showed that NE participated in the structure of the sponge affecting its stability and in vitro release kinetics. When incubated with HCT 116 and Caco-2 cell lines, the NE proved to be cytocompatible over a wide concentration range. Finally, the in vivo biodistribution of the nanocomposite was evaluated after oral gavage in healthy mice. The intestinal retention of NE was highly enhanced when loaded in the sponge compared to the NE suspension. Overall, our results demonstrated that the developed nanocomposite sponge is a promising system for sustained drug intestinal delivery.

In-vivo wound healing activity of a novel composite sponge loaded with mucilage and lipoidal matter of Hibiscus species

Many researches have been undergone to hasten the natural wound healing process. In this study, several Hibiscus species (leaves) were extracted with petroleum ether, methanol, and their mucilage was separated. All the tested species extracts were assessed for their viability percentage using the water-soluble tetrazolium. H.syriacus was the plant of choice to be incorporated in a new drug delivery system and evaluated for its wound healing activity. H.syriacus petroleum ether extract (PEE) showed a high percentage of palmitic and oleic acids while its mucilage demonstrated high glucosamine and galacturonic acid. It was selected to be formulated and pharmaceutically evaluated into three different composite sponges using chitosan in various ratios. Fourier-transformed infrared spectroscopy investigated the chemical interaction between the utilized sponges' ingredients. Morphological characteristics were evaluated using scanning electron microscopy. H.syriacus composite sponge of mucilage: chitosan (1:5) was loaded with three different concentrations of PEE. Medicated formulations were assessed in rat model of excision wound model. The wound healing ability was clearly proved by the clinical acceleration, histopathological examination, and modulation of correlated inflammatory parameters as tumor necrosis factor in addition to vascular endothelial growth factor suggesting a promising valuable candidate that supports the management of excision wounds using single-dose preparation.

Nanocomposite systems for precise oral delivery of drugs and biologics

Oral delivery is considered the favoured route of administration for both local and systemic delivery of active molecules. Formulation of drugs in conventional systems and nanoparticles has provided opportunities for targeting the gastrointestinal (GI) tract, increasing drug solubility and bioavailability. Despite the achievements of these delivery approaches, the development of a product with the ability of delivering drug molecules at a specific site and according to patients' needs remains a challenging endeavour. The complexity of the physicochemical properties of colloidal systems, their stability in different regions of the gastrointestinal tract, and interaction with the restrictive biological barriers hampered their success for oral precise medicine. To overcome these issues, nanoparticles have been combined with polymers to create hybrid nanosystems, namely nanocomposites. They offer enormous possibilities of structural and mechanical modifications to both nanoparticles and polymeric matrixes to generate systems with new properties, functions, and applications for oral delivery. In this review, nanocomposites' physicochemical and functional properties intended to target specific regions of the GI tract-oral cavity, stomach, small bowel, and colon-are analysed. In parallel, it is provided an insight in the nanocomposite solutions for oral delivery intended for systemic and local absorption, together with a focus on inflammatory bowel diseases (IBDs). Additional difficulties in managing IBD related to the alteration in the physiology of the intestine are described. Finally, future perspectives and opportunities for advancement in this field are discussed.

Magnetic Field Triggerable Macroporous PDMS Sponge Loaded with an Anticancer Drug, 5-Fluorouracil

This study aims to prepare, optimize, and characterize magnetic-field-sensitive sugar-templated polydimethylsiloxane (PDMS) sponges for localized delivery of an anticancer drug, 5-fluorouracil (FLU). For this purpose, different concentrations of carbonyl iron (CI) and magnetite Fe₃O₄ nanopowders were embedded as magnetosensitive materials in PDMS resins for the fabrication of macroporous sponges via a sugar-template process. The process is environmentally friendly and simple. The fabricated interconnected macroporous magnetic particles loaded PDMS sponges possess flexible skeletons and good recyclability because of their recoverability after compression (deformation) without any breakdown. The prepared magnetic PDMS sponges were evaluated for their morphology (SEM and EDS), porosity (absorbency), elastic modulus, deformation under a magnetic field, thermostability, and in vitro cell studies. All physicochemical and magnetomechanical analysis confirmed that the optimized magnetic-field-sensitive PDMS sponge can provide an efficient method for delivering an on-demand dose of anticancer drug solutions at a specific location and timing with the aid of controlled magnetic fields.

Solid lipid nanoparticle-loaded mucoadhesive buccal films - Critical quality attributes and in vitro safety & efficacy

The objective of this work was to develop and characterize solid lipid nanoparticle (SLN)-loaded mucoadhesive films to reveal their potential as successful drug formulations. SLNs based on lipid (Lipoid S100) and surfactant (polysorbate 80) were prepared using the solvent-injection method, and their properties examined using experimental designs. Further, the marker coumarin 6 (C6) was solubilized in the particles as a model for a lipophilic drug. Lipid and surfactant concentrations influenced the particle size, while C6 had minor impact. The particle size distribution was narrow and the storage stability satisfactory for 4 months (4 ℃). The incorporation of the nanoparticles into a film matrix consisting of HPMC and glycerol, increased film thickness and flexibility, and slightly decreased the mechanical strength. The mucin interaction and disintegration time of the films were unimpaired. Film uniformity was satisfactory. Solubilisation in SLNs reduced the rate and extent of permeation of C6 through a monolayer of mucus-producing HT29-MTX cells. When the particles were incorporated into the mucoadhesive film, this effect was compensated for. In conclusion, this project was a first step in the successful development of an SLN-loaded mucoadhesive film formulation and served its purpose in revealing the formulation's uniformity, mucoadhesiveness and biocompatibility.

Freeze-Dried Matrices for Buccal Administration of Propranolol in Children: Physico-Chemical and Functional Characterization

Buccal matrices represent a widely accepted dosage form permitting a convenient, easy, reliable drug administration and reducing administration errors. The aim of this study was the development of mucoadhesive buccal matrices for propranolol administration in children. Matrices were obtained by freeze-drying of drug loaded polymeric solutions based on gum tragacanth (GT), pectin (PEC), hydroxypropylmethylcellulose (HPMC), sodium hyaluronate (HA), gelatin (GEL), chitosan (CH) or a mixture of CH and HPMC (CH/HPMC). Matrices were characterized for drug solid state, morphology, water-uptake, mucoadhesion ability, in vitro drug release and permeation through porcine epithelium. The most promising formulations were tested for in vitro biocompatibility in human dental pulp fibroblasts. The preparative method and the polymeric composition influenced the drug solid state, as a complete amorphization as well as different polymorphic forms were observed. GEL and PEC guaranteed a fast and complete drug release due to their rapid dissolution, while for the other matrices the release was influenced by drug diffusion through the viscous gelled matrix. Moreover, matrices based on CH and CH/HPMC showed the best mucoadhesive properties, favoured the drug permeation, in virtue of CH ability to interfere with the lipid organization of biological membrane, and were characterized by a good biocompatibility profile.

Development of a Multifunctional Bioerodible Nanocomposite Containing Metronidazole and Curcumin to Apply on L-PRF Clot to Promote Tissue Regeneration in Dentistry

Teeth extractions are often followed by alveolar bone reabsorption, although an adequate level of bone is required for reliable rehabilitations by dental implants. Leukocyte and platelet-rich fibrin (L-PRF) has been widely applied in regenerative procedures and with antibiotic and antioxidant agents could play an essential role in hard and soft tissue healing. In this work, a nanocomposite (Sponge-C-MTR) consisting of a hyaluronate-based sponge loaded with metronidazole (MTR) and nanostructured lipid carriers containing curcumin (CUR-NLC) was designed to be wrapped in the L-PRF™ membrane in the post-extraction sockets and characterized. CUR-NLCs, obtained by homogenization followed by high-frequency sonication of the lipid mixture, showed loading capacity (5% w/w), drug recovery (95% w/w), spherical shape with an average particle size of 112.0 nm, and Zeta potential of -24 mV. Sponge-C-MTR was obtained by entrapping CUR-NLC in a hydrophilic matrix by a freeze-drying process, and physico-chemical and cytocompatibility properties were evaluated. Moreover, the aptitude of CUR and MTR to the penetrate and/or permeate both L-PRF™ and porcine buccal tissue was assessed, highlighting MTR penetration and CUR accumulation promoted by the system. The results positively support the action of nanocomposite in dental tissues regeneration when applied together with the L-PRF™.

Formulating SLN and NLC as Innovative Drug Delivery Systems for Non-Invasive Routes of Drug Administration

Colloidal carriers diverge depending on their composition, ability to incorporate drugs and applicability, but the common feature is the small average particle size. Among the carriers with the potential nanostructured drug delivery application there are SLN and NLC. These nanostructured systems consist of complex lipids and highly purified mixtures of glycerides having varying particle size. Also, these systems have shown physical stability, protection capacity of unstable drugs, release control ability, excellent tolerability, possibility of vectorization, and no reported production problems related to large-scale. Several production procedures can be applied to achieve high association efficiency between the bioactive and the carrier, depending on the physicochemical properties of both, as well as on the production procedure applied. The whole set of unique advantages such as enhanced drug loading capacity, prevention of drug expulsion, leads to more flexibility for modulation of drug release and makes Lipid-based nanocarriers (LNCs) versatile delivery system for various routes of administration. The route of administration has a significant impact on the therapeutic outcome of a drug. Thus, the non-invasive routes, which were of minor importance as parts of drug delivery in the past, have assumed added importance drugs, proteins, peptides and biopharmaceuticals drug delivery and these include nasal, buccal, vaginal and transdermal routes. The objective of this paper is to present the state of the art concerning the application of the lipid nanocarriers designated for non-invasive routes of administration. In this manner, this review presents an innovative technological platform to develop nanostructured delivery systems with great versatility of application in non-invasive routes of administration and targeting drug release.

Impact of the mucoadhesive lyophilized wafer loaded with novel carvedilol nano-spanlastics on biochemical markers in the heart of spontaneously hypertensive rat models

The purpose of this investigation was to encapsulate carvedilol, a model beta-blocker antihypertensive into nano-spanlastics, followed by incorporation into 1% CMC wafer to afford a mucoadhesive buccal drug delivery system, targeting to sidestep the first-pass metabolism, improving the drug absorption and pharmacological effect, achieving non-invasive buccal delivery for treating hypertension. Carvedilol-loaded nano-spanlastics were rendered by ethanol injection technique, using 2³ factorial design. The effect of formulation variables was investigated on nano-spanlastic characteristics. The optimal nano-spanlastic formulation (S2; containing 20% Brij 97) exhibited particle size (239.8 ± 5 nm), entrapment efficiency (98. 16 ± 1.44%), deformability index (8.74 ± 0.42 g), and the flux after 24 h (J_max) (22.5 ± 0.25 (μg/cm²/h) with enhancement ratio 2.87 as well as excellent stability after storage. Permeation study verified the preeminence of the S2 formula. A confocal laser scanning microscope showed deep penetration of S2 through sheep buccal mucosa formula compared to rhodamine B solution. S2-based wafer showed acceptable characters (pH, swelling, drug content, residence time, and release rate). In vivo studies (pharmacodynamic study and biochemical evaluation) showed considerable improvement in blood pressure, the profile of the lipid, oxidant stress biomarkers, and cardiac markers. Histopathological studies revealed the superiority of S2 wafer in the protection of heart tissues over Carvid®. The results achieved indicate that nano-spanlastic-based wafer offers a promising improving trans-buccal carvedilol delivery system. Graphical abstract.

Carrageenan-Based Acyclovir Mucoadhesive Vaginal Tablets for Prevention of Genital Herpes

Women are the most affected by genital herpes, which is one of the most common sexually transmitted infections, affecting more than 400 million people worldwide. The application of vaginal microbicides could provide a safe method of protection. Acyclovir is a safe and effective medication for vaginal administration, and numerous benefits have been observed in the treatment of primary or recurrent lesions due to genital herpes. Vaginal tablets based on a combination of the polymers iota-carrageenan and hydroxypropyl methylcellulose were developed for the controlled release of acyclovir. Swelling, mucoadhesion and drug release studies were carried out in simulated vaginal fluid. The tablets, containing a combination of iota-carrageenan and hydroxypropyl methylcellulose, have an adequate uptake of the medium that allows them to develop the precise consistency and volume of gel for the controlled release of acyclovir. Its high mucoadhesive capacity also allows the formulation to remain in the vaginal area long enough to ensure the complete release of acyclovir. These promising formulations for the prevention of genital herpes deserve further evaluation.

Promoted Antitumor Activity of Myricetin against Lung Carcinoma Via Nanoencapsulated Phospholipid Complex in Respirable Microparticles

PURPOSE

Myricetin (MYR) flavonoid is well-recognized for its antioxidant, anti-inflammatory and anti-tumor potential. Introducing nanomedicine was the ultimate resort to solve the imperfections of this nutraceutical, namely solubility, stability and delivery issues. The study, thus, aims at developing inhalable microparticles comprising MYR solid lipid nanoparticles (SLNs) for lung cancer therapy.

METHODS

A two-step preparation procedure starting with complexation of MYR with the phospholipid Lipoid-S100, followed by nanoencapsulation in Gelucire-based, surfactant-free SLNs was developed. SLNs were characterized in terms of physicochemical properties, MYR loading, release behavior as well as anti-tumor potential and cellular uptake. Respirable microparticles were then obtained by spray drying SLNs with carbohydrate carriers. Their size, flowability and pulmonary deposition pattern were assessed.

RESULTS

Optimized SLNs were 75.98 nm in diameter with a zeta-potential of -22.5 mV, and an encapsulation efficiency of 84.5%. Attempts to ameliorate drug loading implicate MYR-phospholipid complexation (MYR-PH-CPX) prior to its entrapment in SLNs, which ensured 5-fold increase in drug loading. Viability assays were modified to guarantee MYR chemical stability. Superior antitumor activity of MYR-phospholipid-complex and 3-fold reduction in IC₅₀ were accomplished with MYR-SLNs. This could be related to enhanced cellular uptake revealed by confocal imaging and doubled fluorescence intensity. SLNs entrapping MYR-PH-CPX were spray-dried with carbohydrate carriers to produce respirable microparticles. The latter ensured MMAD of 2.39 μm and span index of 1.84, in addition to good flowability and > 80% release over 8 h. Deposition experiments revealed MMAD of 2.77 μm, FPF of 81.23 and EF of 93% indicating particle deposition in the targeted bronchial region.

CONCLUSIONS

The study highlights the ability of phospholipid-complex on the nanoencapsulation, cellular uptake and antitumor activity of MYR. Formulation of respirable microparticles gives promises of efficacious therapy of lung carcinoma.

Fabrication, characterization and practical efficacy of Myristica fragrans essential oil nanoemulsion delivery system against postharvest biodeterioration

The present study deals with encapsulation of Myristica fragrans essential oil (MFEO) into chitosan nano-matrix, their characterization and assessment of antimicrobial activity, aflatoxin inhibitory potential, safety profiling and in situ efficacy in stored rice as environment friendly effective preservative to control the postharvest losses of food commodities under storage. Surface morphology of MFEO-chitosan nanoemulsion as well as encapsulation of MFEO was confirmed through SEM, FTIR and XRD analysis. In vitro release characteristics with biphasic burst explained controlled volatilization from nanoencapsulated MFEO. Unencapsulated MFEO exhibited fungitoxicity against 15 food borne molds and inhibited aflatoxin B₁ secretion by toxigenic Aspergillus flavus LHP R14 strain. In contrast, nanoencapsulated MFEO showed better fungitoxicity and inhibitory effect on aflatoxin biosynthesis at lower doses. In situ efficacy of unencapsulated and nanoencapsulated MFEO on stored rice seeds exhibited effective protection against fungal infestation, aflatoxin B₁ contamination, and lipid peroxidation. Both the unencapsulated and nanoencapsulated MFEO did not affect the germination of stored rice seeds confirming non-phytotoxic nature. In addition, negligible mammalian toxicity of unencapsulated MFEO (LD₅₀ = 14,289.32 μL/kg body weight) and MFEO loaded chitosan nanoemulsion (LD₅₀ = 9231.89 μL/kg body weight) as revealed through favorable safety profile recommend the industrial significance of nanoencapsulated MFEO as an effective green alternative to environmentally hazardous synthetic pesticides for protection of food commodities during storage.

Carboxymethyl cellulose-based wafer enriched with resveratrol-loaded nanoparticles for enhanced wound healing

The present study aimed to prepare and investigate the wound healing potential of carboxymethyl cellulose (CMC)-based wafers incorporated with resveratrol (RSV)-loaded cellulose acetate butyrate (CAB) NPs. Accordingly, RSV-CAB NPs were prepared using the solvent evaporation method. The effect of different formulation parameters (polymer content, surfactant concentration, and the volume ratio of aqueous phase to organic phase) on the properties of NPs was investigated using the Box-Behnken design. Then, the optimized NPs were incorporated in wafers comprising CMC combined with hydroxyl propyl methyl cellulose (HPMC) or chitosan. Hydration capacity, porosity, adhesive strength, and hardness of the prepared nanocomposite wafers were examined. Optimized formulation was spherical, showing the particle size, polydispersity index, zeta potential, encapsulation efficiency %, drug loading %, and release efficiency % of 248.5 nm, 0.38, - 1.59, 87.58, 25.94, and 67.10, respectively. The CMC-HPMC wafers exhibited higher porosity, hydration capacity, and adhesive performance, as compared with the CMC wafers alone and CMC-chitosan wafers. Wound healing test and histological evaluation in the excisional wounds of the rats showed that the RSV-NPs-wafers were more effective as a healing accelerator, in comparison to wafers without drug or those containing the free RSV. These results demonstrated the potential of the RSV-NPs-wafer in wound healing drug delivery applications. Graphical abstract.

In vivo Antiplasmodial Activity of Curcumin-Loaded Nanostructured Lipid Carriers

Background:

It was shown that curcumin (Cur) has anti-plasmodium activity, however, its weak bioavailability, rapid metabolism, and limited chemical stability has restricted its application in clinical usages. Nanostructured lipid carriers (NLCs) are a type of drug-delivery systems (DDSs) which their core matrix is composed of both solid and liquid lipids.

Objective:

The aim of the current study was to prepare and characterize curcumin-loaded nanostructured lipid carriers (Cur-NLC) for malaria treatment.

Methods:

For the production of NLC, coconut oil and cetyl palmitate were selected as a liquid and solid lipid, respectively. In order to prepare the Cur-NLC, the microemulsion method was applied. General toxicity assay on Artemia salina and also hemocompatibility was investigated. Antimalarial activity was studied on mice infected with Plasmodium berghei.

Results:

The NLCs mean particle size and polydispersity index (PI) was 145 nm and 0.3, respectively. Moreover, the zeta potential of the Cur-NLC was −25 mV, as well as, the NLCs showed pseudo-spherical shape which revealed via transmission electron microscopy (TEM). The loading capacity and encapsulation efficacy of the obtained Cur-NLC were 3.1 ± 0.015% and 74 ± 3.32%, respectively. In vitro, Cur release profiles showed a sustained-release pattern up to 5 days in synthesized Cur-NLC. The results of in vivo anti-plasmodial activity against P. berghei revealed that antimalarial activity of Cur-NLC was high 2-fold compared with bare Cur at the tested dosage level.

Conclusion: :

The results of this study showed that NLC would be used as a potential nanocarrier for the treatment of malaria.

Bioadhesive Matrix Tablets Loaded with Lipophilic Nanoparticles as Vehicles for Drugs for Periodontitis Treatment: Development and Characterization

Periodontitis treatment is usually focused on the reduction or eradication of periodontal pathogens using antibiotics against anaerobic bacteria, such as metronidazole (MTR). Moreover, recently the correlation between periodontal diseases and overexpression of reactive oxygen species (ROS) led to the introduction of antioxidant biomolecules in therapy. In this work, bioadhesive buccal tablets, consisting of a hydrophilic matrix loaded with metronidazole and lipophilic nanoparticles as a vehicle of curcumin, were developed. Curcumin (CUR)-loaded nanostructured lipid carriers (NLC) were prepared using glycyrrhetic acid, hexadecanol, isopropyl palmitate and Tween®80 as a surfactant. As method, homogenization followed by high-frequency sonication was used. After dialysis, CUR-NLC dispersion was evaluated in terms of drug loading (DL, 2.2% w/w) and drug recovery (DR, 88% w/w). NLC, characterized by dynamic light scattering and scanning electron microscopy (SEM), exhibited a spherical shape, an average particle size of 121.6 nm and PDI and PZ values considered optimal for a colloidal nanoparticle dispersion indicating good stability of the system. Subsequently, a hydrophilic sponge was obtained by lyophilization of a gel based on trehalose, Natrosol and PVP-K90, loaded with CUR-NLC and MTR. By compression of the sponge, matrix tablets were obtained and characterized in term of porosity, swelling index, mucoadhesion and drugs release. The ability of the matrix tablets to release CUR and MTR when applied on buccal mucosa and the aptitude of actives to penetrate and/or permeate the tissue were evaluated. The data demonstrate the ability of NLC to promote the penetration of CUR into the lipophilic domains of the mucosal membrane, while MTR can penetrate and permeate the mucosal tissue, where it can perform a loco-regional antibacterial activity. These results strongly support the possibility of using this novel matrix tablet for delivering MTR together with CUR for topical treatment of periodontal diseases.

A mini-review on drug delivery through wafer technology: Formulation and manufacturing of buccal and oral lyophilizates

A great number of patients have difficulty swallowing or needle fear. Therefore, buccal and orodispersible dosage forms (ODFs) represent an important strategy to enhance patient compliance. Besides not requiring water intake, swallowing or needles, these dosage forms allow drug release modulation. ODFs include oral lyophilizates or wafers, which present even faster disintegration than its compressed counterparts. Lyophilization can also produce buccal wafers that adhere to mucosa for sustained drug release. Due to the subject relevance and recent research growth, this review focused on oral lyophilizate production technology, formulation features, and therapy gains. It includes Critical Quality Attributes (CQA) and Critical Process Parameters (CPP) and discusses commercial and experimental examples. In sum, the available commercial products promote immediate drug release mainly based on biopolymeric matrixes and two production technologies. Therapy gains include substitution of traditional treatments depending on parenteral administration and patient preference over classical therapies. Experimental wafers show promising advantages as controlled release and drug enhanced stability. All compiled findings encourage the development of new wafers for several diseases and drug molecules.

Pharmacokinetic Aspects of Nanoparticle-in-Matrix Drug Delivery Systems for Oral/Buccal Delivery

Oral route maintains its predominance among the ones used for drug delivery, especially when medicines are self-administered. If the dosage form is solid, therapy gains in dose precision and drug stability. Yet, some active pharmaceutical substances do not present the required solubility, permeability, or release profile for incorporation into traditional matrices. The combination of nanostructured drugs (nanoparticle [NP]) with these matrices is a new and little-explored alternative, which could bring several benefits. Therefore, this review focused on combined delivery systems based on nanostructures to administer drugs by the oral cavity, intended for buccal, sublingual, gastric, or intestinal absorption. We analyzed published NP-in-matrix systems and compared main formulation characteristics, pharmacokinetics, release profiles, and physicochemical stability improvements. The reported formulations are mainly semisolid or solid polymers, with polymeric or lipid NPs and one active pharmaceutical ingredient. Regarding drug specifics, most of them are poorly permeable or greatly metabolized. The few studies with pharmacokinetics showed increased drug bioavailability and, sometimes, a controlled release rate. From our knowledge, the gathered data make up the first focused review of these trendy systems, which we believe will help to gain scientific deepness and future advancements in the field.

Lysozyme Mucoadhesive Tablets Obtained by Freeze-Drying

Lysozyme is particularly attractive for the local treatment of oral pathologies related to microbiological infections. However, the requirement of a prolonged release is difficult to achieve because of saliva swallowing and of the protein denaturation which can occur during production and storage of a dosage form. This work demonstrates the feasibility to prepare lysozyme mucoadhesive tablets by freeze-drying. Tablets were prepared by using alginate (ALG) physically "cross-linked" with calcium ion and different grades of hydroxypropyl methylcellulose (HPMC) (i.e., E5, E50, or K100). The tablets were characterized in terms of swelling or erosion behavior, in vitro mucoadhesive properties, lysozyme activity (Micrococcus lysodeikticus), drug release and ability to inactivate Staphylococcus aureus. The formulations prepared with HPMC K100 were discarded because of the fast erosion. All other formulations allowed a sustained release over at least 6 h. Independently of composition, lysozyme activity (78,311 ± 1873 Units/mg) significantly decreased in the case of tablets containing 5% and 10% w/w of protein (55,000 Units/mg and 33,000 Units/mg, respectively). Conversely, no modifications occurred in the case of tablets containing 1% w/w lysozyme. The formulation prepared by ALG/HPMC E5 7/3 ratio was efficacious against S. aureus. After 3 months of storage at 5 ± 3°C, no significant decrease in lysozyme activity was observed.

Nanostructuring lipid carriers using Ridolfia segetum (L.) Moris essential oil

The therapeutic potential of essential oils is widely recognized since antiquity, due to their antibacterial, antifungal, anti-inflammatory and immuno-modulatory properties. In particular, their physicochemical characteristics, such as lipophilicity and permeation enhancement effect have sparked attention for the development of innovative lipid nanosystems. The present work aimed at developing a differentiated nanostructured lipid carrier (NLC) based formulation for topical application, using the Ridolfia segetum essential oil (REO), isolated by hydrodistillation from this Portuguese aromatic plant, with a dual key function, as active and simultaneously nanostructuring component of the nanoparticles. The incorporation of the essential oil in the solid lipid matrix, followed by the respective hot high-pressure homogenization, led to particles with a size of 143 ± 5 nm, along with a polydispersity index of 0.21, a zeta potential of -16.3 ± 0.6 mV, encapsulation efficacy of ca. 100% and loading capacity of 1.4%. A comprehensive physicochemical characterization of the lipid nanosystem, including morphology, structural, thermal and accelerated stability analysis confirmed its nanostructured nature. REO-NLC was further jellified for designing an appropriate semisolid topical dosage form. In vitro release, permeation and skin retention studies evidenced a sustained release behaviour and a reservoir-like effect, suitable for a prolonged topical delivery. Cytotoxicity studies, performed in fibroblasts and keratinocytes, revealed the biocompatibility of the developed formulations. This work highlights the critical role of REO as a multiaddressable compound, both as active pharmaceutical ingredient and nanostructuring agent, able to tailor the permeation enhancement profile of nanoparticles towards topical delivery purposes and concomitantly presenting a safety profile for cosmetic and/or pharmaceutical purposes.

Oral Drug Delivery Systems for Ulcerative Colitis Therapy: A Comparative Study with Microparticles and Nanoparticles

Background:

Oral administrations of microparticles (MPs) and nanoparticles (NPs) have been widely employed as therapeutic approaches for the treatment of ulcerative colitis (UC). However, no previous study has comparatively investigated the therapeutic efficacies of MPs and NPs.

Methods:

In this study, curcumin (CUR)-loaded MPs (CUR-MPs) and CUR-loaded NPs (CUR-NPs) were prepared using a single water-in-oil emulsion solvent evaporation technique. Their therapeutic outcomes against UC were further comparatively studied.

Results:

The resultant spherical MPs and NPs exhibited slightly negative zeta-potential with average particle diameters of approximately 1.7 &#181;m and 270 nm, respectively. It was found that NPs exhibited a much higher CUR release rate than MPs within the same period of investigation. In vivo experiments demonstrated that oral administration of CUR-MPs and CUR-NPs reduced the symptoms of inflammation in a UC mouse model induced by dextran sulfate sodium. Importantly, CUR-NPs showed much better therapeutic outcomes in alleviating UC compared with CUR-MPs.

Conclusion:

NPs can improve the anti-inflammatory activity of CUR by enhancing the drug release and cellular uptake efficiency, in comparison with MPs. Thus, they could be exploited as a promising oral drug delivery system for effective UC treatment.

Freeze-Dried Matrices Based on Polyanion Polymers for Chlorhexidine Local Release in the Buccal and Vaginal Cavities

Chlorhexidine (CLX) is a wide spectrum cationic antimicrobial used for prevention and treatment of infections of buccal and vaginal cavities. To increase the residence time of CLX-based formulations at the application site and consequently reduce the daily dose frequency, new formulations composed of mucoadhesive polymers should be designed. The objective of this work was the development of matrices based on polyanionic polymers, such as sodium alginate, carboxymethylcellulose, xanthan gum and sodium hyaluronate, aimed to prolong the local release of CLX into the buccal or vaginal cavity. Matrices were prepared by freeze-drying and comply with 2 different preparative methods and characterized in terms of resistance to compression, water uptake ability, mucoadhesion, in vitro drug release behavior and antimicrobial activity toward representative pathogens of buccal and vaginal cavities. Results showed that the selection of suitable polymers associated to the adequate preparative method allowed to modulate matrix ability to hydrate, adhere to the mucosa and release the drug as well as to exert antimicrobial activity. In particular, matrix based on sodium hyaluronate was found to be the best performing formulation and could represent a versatile system for local release of CLX with potential application in both buccal and vaginal cavities.

Liquid Crystalline Nanostructures as PEGylated Reservoirs of Omega-3 Polyunsaturated Fatty Acids: Structural Insights toward Delivery Formulations against Neurodegenerative Disorders

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) are bioactive lipids with considerable impact in medicine and nutrition. These compounds exert structuring effects on the cellular membrane organization, regulate the gene expression, and modulate various signaling cascades and metabolic processes. The purpose of the present work is to demonstrate the structural features of ω-3 PUFA-containing three-dimensional supramolecular lipid assemblies suitable for pharmaceutical applications that require soft porous carriers. We investigate the liquid crystalline structures formed upon mixing of eicosapentaenoic acid (EPA, 20:5) with the lyotropic nonlamellar lipid monoolein and the formation of multicompartment assemblies. Starting with the monoolein-based lipid cubic phase, double membrane vesicles, cubosome precursors, sponge-type particles (spongosomes), mixed intermediate nonlamellar structures, and multicompartment assemblies are obtained through self-assembly at different amphiphilic compositions. The dispersions containing spongosomes as well as nanocarriers with oil and vesicular compartments are stabilized by PEGylation of the lipid/water interfaces using a phospholipid with a poly(ethylene glycol) chain. The microstructures of the bulk mixtures were examined by cross-polarized light optical microscopy. The dispersed liquid crystalline structures and intermediate states were studied by small-angle X-ray scattering, cryogenic transmission electron microscopy, and quasielastic light scattering techniques. They established that PUFA influences the phase type and the sizes of the aqueous compartments of the liquid crystalline carriers. The resulting multicompartment systems and stealth nanosponges may serve as mesoporous reservoirs for coencapsulation of ω-3 PUFA (e.g., EPA) with water-insoluble drugs and hydrophilic macromolecules toward development of combination treatment strategies of neurodegenerative and other diseases.

Laminated chitosan-based composite sponges for transmucosal delivery of novel protamine-decorated tripterine phytosomes: Ex-vivo mucopenetration and in-vivo pharmacokinetic assessments

In the current study, laminated chitosan (CS):hydroxypropyl methylcellulose (HPMC) composite sponges were exploited as solid matrices for buccal delivery of tripterine phytosomes functionalized with novel mucopenetrating protamine layer (PRT-TRI-PHY). Tripterine (TRI) is a herbal drug widely investigated as a potential anticancer candidate against various types of cancers. However, clinical use of TRI is handicapped by its low oral bioavailability. To surmount TRI pharmaceutical obstacles, TRI phytosomes (TRI-PHY) were prepared using solvent evaporation technique then coated with a protamine layer via electrostatic assembly process. The developed PRT-TRI-PHY showed a nano-metric size of 250 nm and positive zeta potential (+21.6 mV). Sponges loaded with PRT-TRI-PHY demonstrated a sustained release profile with superior mucoadhesion characteristics compared with the counterparts loaded with uncoated TRI-PHY. The ex-vivo permeation study via chicken pouch mucosa revealed that sponges loaded with PRT-TRI-PHY demonstrated 2.3-folds higher flux value compared with sponges loaded with uncoated TRI-PHY. Additionally, in-vivo pharmacokinetic study in healthy rabbits revealed the significantly higher bioavailability of PRT-TRI-PHY compared with TRI-PHY with relative bioavailability of 244%. Conclusively, mucoadhesive CS-HPMC sponges loaded with a novel mucopenetrating nanocarrier, PRT-TRI-PHY, could significantly improve the absorption of tripterine via buccal mucosa which would be of prime importance for its clinical utility.

Marrubiin-loaded solid lipid nanoparticles' impact on TNF-α treated umbilical vein endothelial cells: A study for cardioprotective effect

Oxidative stress possesses a key role in the onset and development of cardiovascular diseases (CVDs), thus it can be an efficient target to tackle such ailment. Marrubiin, a bioactive diterpene, is a potent antioxidant against oxidative stress. Herein, we aimed to formulate marrubiin loaded solid lipid nanoparticles (SLNs) to improve its pharmacokinetics and bioavailability and also to investigate free drug and formulation's protective impact against intracellular reactive oxygen species (ROS) generation in HUVECs. Marrubiin-SLNs were formulated using hot homogenization/solidification method and then were subjected to physicochemical characterizations, i.e. size, zeta potential, morphology, polydispersity index (PDI), encapsulation efficiency (% EE), drug loading/content and physical stability assessments. MTT assay was performed to study the cytotoxicity of the intact and SLN incorporated marrubiin on HUVECs. Further, the antioxidant property of marrubiin and formulations was evaluated using DPPH radical scavenging assay and their protective effect against TNF-α induced oxidative stress was assessed by the means of intracellular ROS assessment, and also apoptosis/necrosis, cell cycle, and DNA fragmentation assays. Electron microscopy analysis showed spherical monodispersed SLNs with the size less than 100 nm, particle/zeta size analyses also approved the size of particles with a zeta potential of -1.28 ± 0.17 mV. Results also showed high EE (98%), drug loading (31.74 mg/g) with 3.15% drug content. In vitro release studies revealed about 90% of marrubiin cumulative release during 24 h. The stability of marrubiin-SLNs in terms of size, zeta potential, polydispersity index, EE and drug leakage was approved. Marrubiin antioxidant stability after formulation was approved by DPPH analysis. MTT cell survival assay showed no significant cytotoxicity after 24 h and 48 h. Intracellular ROS detection assay revealed that marrubiin and marrubiin-SLNs, play protective effect against TNF-α induced oxidative stress in HUVECs which was further approved by apoptosis assessment. Conclusively, based on our findings, marrubiin nanoparticles are proposed as a preventive/therapeutic remedy against disorders elicited by increased levels of intracellular ROS in CVDs.