Gelatin Coated Hybrid Lipid Nanoparticles for Oral Delivery of Amphotericin B

Gemcitabine-Phospholipid Complex Loaded Lipid Nanoparticles for Improving Drug Loading, Stability, and Efficacy against Pancreatic Cancer

This study aims to encapsulate gemcitabine (GEM) using a phospholipid complex (PLC) in lipid nanoparticles (NPs) to achieve several desirable outcomes, including high drug loading, uniform particle size, improved therapeutic efficacy, and reduced toxicities. The successful preparation of GEM-loaded lipid NPs (GEM-NPs) was accomplished using the emulsification-solidification method, following optimization through Box-Behnken design. The size of the GEM-NP was 138.5 ± 6.7 nm, with a low polydispersity index of 0.282 ± 0.078, as measured by a zetasizer and confirmed by transmission electron and atomic force microscopy. GEM-NPs demonstrated sustained release behavior, surpassing the performance of the free GEM and phospholipid complex. Moreover, GEM-NPs exhibited enhanced cytotoxicity, apoptosis, and cell uptake in Panc-2 and Mia PaCa cells compared to the free GEM. The in vivo pharmacokinetics revealed approximately 4-fold higher bioavailability of GEM-NPs in comparison with free GEM. Additionally, the pharmacodynamic evaluation conducted in a DMBA-induced pancreatic cancer model, involving histological examination, serum IL-6 level estimation, and expression of cleaved caspase-3, showed the potential of GEM-NPs in the management of pancreatic cancer. Consequently, the lipid NP-based approach developed in our investigation demonstrates high stability and uniformity and holds promise for enhancing the therapeutic outcomes of GEM.

Self-actuating inflammation responsive hydrogel microsphere formulation for controlled drug release in rheumatoid arthritis (RA): Animal trials and study in human fibroblast like synoviocytes (hFLS) of RA patients

Patients with rheumatoid arthritis (RA) often have one or more painfuljoints despite adequate medicine. Local drug delivery to the synovial cavity bids for high drug concentration with minimal systemic adverse effects. However, anti-RA drugs show short half-lives in inflamed joints after intra-articular delivery. To improve the therapeutic efficacy, it is essential to ensure that a drug is only released from the formulation when it is needed. In this work, we developed an intelligent "Self-actuating" drug delivery system where Disease-modifying anti-rheumatic Drug (DMARD) methotrexate is incorporated within a matrix intended to be injected directly into joints. This formulation has the property to sense the need and release medication only when joints are inflamed in response to inflammatory enzyme Matrix metalloproteinases (MMP). These enzymes are important proteases in RA pathology, and several MMP are present in augmented levels in synovial fluid and tissues. A high level of MMP present in synovial tissues of RA patients would facilitate the release of drugs in response and ascertain controlled drug release. The formulation is designed to be stable within the joint environment, but to dis-assemble in response to inflammation. The synthesized enzyme-responsive methotrexate (Mtx) encapsulated micron-sized polymer-lipid hybrid hydrogel microspheres (Mtx-PLHM) was physiochemically characterized and tested in synovial fluid, Human Fibroblast like synoviocytes (h-FLS) (derived from RA patients) and a rat arthritic animal model. Mtx-PLHM can self-actuate and augment the release of Mtx drug upon contact with either exogenously added MMP or endogenous MMP present in the synovial fluid of patients with RA. The drug release from the prepared formulation is significantly amplified to several folds in the presence of MMP-2 and MMP-9 enzymes. In the rat arthritic model, Mtx-PLHM showed promising therapeutic results with the significant alleviation of RA symptoms through decrease in joint inflammation, swelling, bone erosion, and joint damage examined by X-ray analysis, histopathology and immune-histology. This drug delivery system would be nontoxic as it releases more drug only during the period of exacerbation of inflammation. This will simultaneously protect patients from unwanted side effects when the disease is inactive and lower the need for repeated joint injections.

Enhancing anti-cancer potential by delivering synergistic drug combinations via phenylboronic acid modified PLGA nanoparticles through ferroptosis-based therapy

In this study, we investigated the potential of the sorafenib (SOR) and simvastatin (SIM) combination to induce ferroptosis-mediated cancer therapy. To enhance targeted drug delivery, we encapsulated the SOR + SIM combination within 4-carboxy phenylboronic acid (CPBA) modified PLGA nanoparticles (CPBA-PLGA(SOR + SIM)-NPs). The developed CPBA-PLGA(SOR + SIM)-NPs exhibited a spherical shape with a size of 213.1 ± 10.9 nm, a PDI of 0.22 ± 0.03, and a Z-potential of -22.9 ± 3.2 mV. Notably, these nanoparticles displayed faster drug release at acidic pH compared to physiological pH. In cellular experiments, CPBA-PLGA(SOR + SIM)-NPs demonstrated remarkable improvements, leading to a 2.51, 2.69, and 2.61-fold decrease in IC50 compared to SOR alone, and a 7.50, 16.71, and 5.11-fold decrease in IC50 compared to SIM alone in MDA-MB-231, A549, and HeLa cells, respectively. Furthermore, CPBA-PLGA(SOR + SIM)-NPs triggered a reduction in glutathione (GSH) levels, an increase in malondialdehyde (MDA) levels, and mitochondrial membrane depolarization in all three cell lines. Pharmacokinetic evaluation revealed a 2.50- and 2.63-fold increase in AUC0-∞, as well as a 1.53- and 2.46-fold increase in mean residence time (MRT) for SOR and SIM, respectively, compared to the free drug groups. Notably, the CPBA-PLGA(SOR + SIM)-NPs group exhibited significant reduction in tumor volume, approximately 9.17, 2.45, and 1.63-fold lower than the control, SOR + SIM, and PLGA(SOR + SIM)-NPs groups, respectively. Histological examination and biomarker analysis showed no significant differences compared to the control group, suggesting the biocompatibility of the developed particles for in-vivo applications. Altogether, our findings demonstrate that CPBA-PLGA(SOR + SIM)-NPs hold tremendous potential as an efficient drug delivery system for inducing ferroptosis, providing a promising therapeutic option for cancer treatment.

Potential lipid-based strategies of amphotericin B designed for oral administration in clinical application

Amphotericin B (AmB) is regarded as a first-line therapy against life-threatening invasive fungal infections. Due to its poor oral bioavailability, AmB is restricted to intravenous administration in clinical practice. As science continues to move forward, two lipid-based formulations are successfully developed for oral AmB administration, currently undergoing phase I clinical trials. Encouragingly, lipid-AmB conjugates with emulsions also exhibit a better bioavailability, which may be another strategy to design oral AmB formulation in clinical practice. Thus, this review mainly focused on the two lipid-based formulations in clinical trials, and discussed the potential perspectives of AmB-lipid conjugation-loaded nanocochleates and emulsions.

Nanogel Particles Based on Modified Nucleosides and Oligosaccharides as Advanced Delivery System

This work addresses the challenge of delivering bioactive molecules by designing biocompatible nanogel particles (NGPs) utilizing rationally modified nature-sourced building blocks: capryl-oligochitosan and oxidized inosine. Capryl substituents endowed the resultant NGPs with membrane-penetration capabilities, while purine-containing inosine allowed H-bond/π-π/π-cation interactions. The prepared NGPs were complexed with carboxyfluorescein-labeled single-stranded oligonucleotide (FAM-oligo) and DsRed-encoding plasmid DNA. The successful delivery of FAM-oligo to the cell cytoplasm of the Nicotiana benthamiana plant was observed. Alexa 555-labeled bovine serum albumin (Alexa 555-BSA) was also efficiently encapsulated and delivered to the plant. In addition to delivering FAM-oligo and Alexa 555-BSA separately, NGPs also successfully co-delivered both biomolecules to the plant. Finally, NGPs successfully encapsulated the drug amphotericin B and reduced its toxicity while maintaining its efficacy. The presented findings suggest that NGPs may become a promising platform for the advanced delivery of bioactive molecules in various applications.

Drug Delivery of Gelatin Nanoparticles as a Biodegradable Polymer for the Treatment of Infectious Diseases: Perspectives and Challenges

In recent years, there has been a growing interest in the use of gelatin nanoparticles (GNPs) for the treatment of infectious diseases. The inherent properties of these nanoparticles make them attractive options for drug delivery. Their biocompatibility ensures that they can interact with biological systems without causing adverse reactions, while their biodegradability ensures that they can break down harmlessly in the body once their function is performed. Furthermore, their capacity for controlled drug release ensures that therapeutic agents can be delivered over a sustained period, thereby enhancing treatment efficacy. This review examines the current landscape of GNP-based drug delivery, with a specific focus on its potential applications and challenges in the context of infectious diseases. Key challenges include controlling drug release rates, ensuring nanoparticle stability under physiological conditions, scaling up production while maintaining quality, mitigating potential immunogenic reactions, optimizing drug loading efficiency, and tracking the biodistribution and clearance of GNPs in the body. Despite these hurdles, GNPs hold promising potential in the realm of infectious disease treatment. Ongoing research and innovation are essential to overcome these obstacles and completely harness the potential of GNPs in clinical applications.

Electrospinning Microencapsulation of Lactobacillus fermentum K73 Using Gelatin as the Main Component of a Food-Grade Matrix

This work aimed to establish the conditions that improve the viability of Lactobacillus fermentum K73 during and after the electrospinning process. A mixture of experimental designs were performed to select the formulation (gelatin and bacterial culture) that improves the probiotic viability after blending and under simulated gastrointestinal conditions. A Box-Behnken design was performed to improve the encapsulation yield and survival during the electrospinning process. For the Box-Behnken design, the factors were soy lecithin and bacteria culture concentration at the blend and collector distance for electrospinning. It was hypothesized that soy lecithin improved the electrospinnability, acting as a surfactant in the mixture and allowing lower voltage to be used during the process. The selected volume ratio of the gelatin (25%)/bacterial culture mixture was 0.66/0.34. The physicochemical parameters of the selected blend were in the recommended range for electrospinning. The conditions that improved the encapsulation yield and survival during electrospinning were 200 g/L of bacterial culture, 2.5% (w/v) soy lecithin, and 7 cm collector distance. The experimental encapsulation yield and survival was 80.7%, with an experimental error of 7.2%. SEM micrographs showed the formation of fibers with gelatin/bacterial culture beads. Encapsulation improved the viability of the probiotic under simulated gastrointestinal conditions compared to free cells.

Targeting active sites of inflammation using inherent properties of tissue-resident mast cells

Mast cells play a pivotal role in initiating and directing host's immune response. They reside in tissues that primarily interface with the external environment. Activated mast cells respond to environmental cues throughout acute and chronic inflammation through releasing immune mediators via rapid degranulation, or long-term de novo expression. Mast cell activation results in the rapid release of a variety of unique enzymes and reactive oxygen species. Furthermore, the increased density of mast cell unique receptors like mas related G protein-coupled receptor X2 also characterizes the inflamed tissues. The presence of these molecules (either released mediators or surface receptors) are particular to the sites of active inflammation, and are a result of mast cell activation. Herein, the molecular design principles for capitalizing on these novel mast cell properties is discussed with the goal of manipulating localized inflammation. STATEMENT OF SIGNIFICANCE: Mast cells are immune regulating cells that play a crucial role in both innate and adaptive immune responses. The activation of mast cells causes the release of multiple unique profiles of biomolecules, which are specific to both tissue and disease. These unique characteristics are tightly regulated and afford a localized stimulus for targeting inflammatory diseases. Herein, these important mast cell attributes are discussed in the frame of highlighting strategies for the design of bioresponsive functional materials to target regions of inflammations.

Liposomal Amphotericin B for Treatment of Leishmaniasis: From the Identification of Critical Physicochemical Attributes to the Design of Effective Topical and Oral Formulations

The liposomal amphotericin B (AmB) formulation, AmBisome^®, still represents the best therapeutic option for cutaneous and visceral leishmaniasis. However, its clinical efficacy depends on the patient's immunological status, the clinical manifestation and the endemic region. Moreover, the need for parenteral administration, its side effects and high cost significantly limit its use in developing countries. This review reports the progress achieved thus far toward the understanding of the mechanism responsible for the reduced toxicity of liposomal AmB formulations and the factors that influence their efficacy against leishmaniasis. It also presents the recent advances in the development of more effective liposomal AmB formulations, including topical and oral liposome formulations. The critical role of the AmB aggregation state and release rate in the reduction of drug toxicity and in the drug efficacy by non-invasive routes is emphasized. This paper is expected to guide future research and development of innovative liposomal formulations of AmB.

Orally Administered Amphotericin B Nanoformulations: Physical Properties of Nanoparticle Carriers on Bioavailability and Clinical Relevance

Amphotericin B is an effective polyene antifungal considered as a “gold standard” in the management of fungal infections. Currently, it is administered mainly by IV due to poor aqueous solubility, which precludes its delivery orally. Paradoxically, IV administration is akin to side effects that have not been fully eliminated even with more recent IV formulations. Thus, the need for alternative formulations/route of administration for amphotericin B remains crucial. The oral route offers the possibility of delivering amphotericin B systemically and with diminished side effects; however, enterocyte permeation remains a constraint. Cellular phagocytosis of submicron particles can be used to courier encapsulated drugs. In this regard, nanoparticulate delivery systems have received much attention in the past decade. This review examines the trajectory of orally delivered amphotericin B and discusses key physical factors of nanoformulations that impact bioavailability. The review also explores obstacles that remain and gives a window into the possibility of realizing an oral nanoformulation of amphotericin B in the near future.

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.

Charge Reversal Polypyrrole Nanocomplex-Mediated Gene Delivery and Photothermal Therapy for Effectively Treating Papillary Thyroid Cancer and Inhibiting Lymphatic Metastasis

As a traditional treatment for papillary thyroid cancer (PTC), surgical resection of diseased tissues often brings lots of inconveniences to patients, and the tumor recurrence and metastasis are difficult to avoid. Herein, we developed a gene and photothermal combined therapy nanosystem based on a polypyrrole (Ppy)-poly(ethylene imine)-siILK nanocomplex (PPR_ILK) to achieve minimally invasive ablation and lymphatic metastasis inhibition in PTC simultaneously. In this system, gelatin-stabilized Ppy mainly acted as a photothermal- and photoacoustic (PA)-responsive nanomaterial and contributed to its well-behaved photosensitivity in the near-infrared region. Moreover, gelatin-stabilized Ppy possessed a charge reversal function, facilitating the tight conjunction of siILK gene at physiological pH (7.35-7.45) and its automatic release into acidic lysosomes (pH 4.0-5.5); the proton sponge effect generated during this process further facilitated the escape of siILK from lysosomes to the cytoplasm and played its role in inhibiting PTC proliferation and lymphatic metastasis. With the guidance of fluorescence and PA bimodal imaging, gene delivery and Ppy location in tumor regions could be clearly observed. As a result, tumors were completely eradicated by photothermal therapy, and the recurrences and metastases were obviously restrained by siILK.

Pharmaceutical liposomal delivery—specific considerations of innovation and challenges

Liposomal technology can enhance drug solubility and stability, achieving codelivery for combination therapy, and modulate the in vivo fate (e.g., site-specific distribution and controlled release), thereby improving treatment outcomes.

Strategic Design of Intelligent-Responsive Nanogel Carriers for Cancer Therapy

Owing to the distinctive constituents of tumor tissue from those healthy organs, nanomedicine strategies show significant potentials in smart drug delivery. Nowadays, stimuli-responsive nanogels are playing increasingly important roles in the application of cancer therapy because of their sensitivity to various internal or external physicochemical stimuli, which exhibit site-specific and markedly enhanced drug release. Besides, nanogels are promising as drug carriers because of their porous structures, good biocompatibility, large surface area, and excellent capability with drugs. Taking advantage of multiresponsiveness, recent years have witnessed the rapid evolution of stimulus-responsive nanogels from monoresponsive to multiresponsive systems; however, there lacks a comprehensive review summarizing these reports. In this Review, we discuss the properties, synthesis, and characterization of nanogels. Moreover, tumor microenvironment and corresponding designing strategies for stimuli-response nanogels, both exogenous (temperature, magnetic field, light) and endogenous (pH, biomolecular, redox, ROS, pressure, hypoxia) are summarized on the basis of the recent advances in multistimuli-responsive nanogel systems. Nanogel and two-dimensional material composites show excellent performance in the field of constructing multistimulus-responsive nanoparticles and precise intelligent drug release integrated system for multimodal cancer diagnosis and therapy. Finally, potential progresses and suggestions are provided for the further design of hybrid nanogels based on emerging two-dimensional materials.

Improved Bioavailability of Poorly Soluble Drugs through Gastrointestinal Muco-Adhesion of Lipid Nanoparticles

Gastrointestinal absorption remains indispensable in the systemic delivery of most drugs, even though it presents several challenges that, paradoxically, may also provide opportunities that can be exploited to achieve maximal bioavailability. Drug delivery systems made from nanoparticle carriers and especially, lipid carriers, have the potential to traverse gastrointestinal barriers and deploy in the lymphatic pathway, which aptly, is free from first pass via the liver. Several poorly soluble drugs have presented improved systemic bioavailability when couriered in lipid nanoparticle carriers. In this review, we propose an additional frontier to enhancing the bioavailability of poorly soluble drugs when encapsulated in lipid nano-carriers by imparting muco-adhesion to the particles through application of appropriate polymeric coating to the lipid carrier. The combined effect of gastrointestinal muco-adhesion followed by lymphatic absorption is a promising approach to improving systemic bioavailability of poorly soluble drugs following oral administration. Evidence to the potential of this approach is backed-up by recent studies within the review.

Nanocarriers for oral delivery of biologics: small carriers for big payloads

Macromolecular therapeutics of biological origin, also known as biologics, have become one of the fastest-growing classes of drugs for management of a range of chronic and acute conditions. The majority of approved biologics are administered via the parenteral route and are thus expensive, have low patient compliance, and have high systemic toxicity. Therefore, tremendous efforts have been devoted to the development of carriers for oral delivery of biologics. This review evaluates key chemical (e.g. pH and enzymes) and physiological challenges to oral biologics delivery. We review the conventional formulation strategies and their limitations, followed by a detailed account of the progress on the use of nanocarriers used for oral biologics delivery, covering organic and inorganic nanocarriers. Lastly, we discuss limitations and opportunities presented by these emerging nanomaterials in oral biologics delivery.

Strategies for Preparing Different Types of Lipid Polymer Hybrid Nanoparticles in Targeted Tumor Therapy

At present, cancer is one of the most common diseases in the world, causing a large number of deaths and seriously affecting people's health. The traditional treatment of cancer is mainly surgery, radiotherapy or chemotherapy. Conventional chemotherapy is still an important treatment, but it has some shortcomings, such as poor cell selectivity, serious side effects, drug resistance and so on. Nanoparticle administration can improve drug stability, reduce toxicity, prolong drug release time, prolong system half-life, and bring broad prospects for tumor therapy. Lipid polymer hybrid nanoparticles (LPNs), which combine the advantages of polymer core and phospholipid shell to form a single platform, have become multi-functional drug delivery platforms. This review introduces the basic characteristics, structure and preparation methods of LPNs, and discusses targeting strategies of LPNs in tumor therapy in order to overcome the defects of traditional drug therapy.

Pharmaceutical Formulations with P-Glycoprotein Inhibitory Effect as Promising Approaches for Enhancing Oral Drug Absorption and Bioavailability

P-glycoprotein (P-gp) is crucial in the active transport of various substrates with diverse structures out of cells, resulting in poor intestinal permeation and limited bioavailability following oral administration. P-gp inhibitors, including small molecule drugs, natural constituents, and pharmaceutically inert excipients, have been exploited to overcome P-gp efflux and enhance the oral absorption and bioavailability of many P-gp substrates. The co-administration of small molecule P-gp inhibitors with P-gp substrates can result in drug–drug interactions and increased side effects due to the pharmacological activity of these molecules. On the other hand, pharmaceutically inert excipients, including polymers, surfactants, and lipid-based excipients, are safe, pharmaceutically acceptable, and are not absorbed from the gut. Notably, they can be incorporated in pharmaceutical formulations to enhance drug solubility, absorption, and bioavailability due to the formulation itself and the P-gp inhibitory effects of the excipients. Different formulations with inherent P-gp inhibitory activity have been developed. These include micelles, emulsions, liposomes, solid lipid nanoparticles, polymeric nanoparticles, microspheres, dendrimers, and solid dispersions. They can bypass P-gp by different mechanisms related to their properties. In this review, we briefly introduce P-gp and P-gp inhibitors, and we extensively summarize the current development of oral drug delivery systems that can bypass and inhibit P-gp to improve the oral absorption and bioavailability of P-gp substrates. Since many drugs are limited by P-gp-mediated efflux, this review is helpful for designing suitable formulations of P-gp substrates to enhance their oral absorption and bioavailability.

Nanoparticles as a Tool for Broadening Antifungal Activities

Fungal infections are diseases that are considered neglected although their infection rates have increased worldwide in the last decades. Thus, since the antifungal arsenal is restricted and many strains have shown resistance, new therapeutic alternatives are necessary. Nanoparticles are considered important alternatives to promote drug delivery. In this sense, the objective of the present study was to evaluate the contributions of newly developed nanoparticles to the treatment of fungal infections. Studies have shown that nanoparticles generally improve the biopharmaceutical and pharmacokinetic characteristics of antifungals, which is reflected in a greater pharmacodynamic potential and lower toxicity, as well as the possibility of prolonged action. It also offers the proposition of new routes of administration. Nanotechnology is known to contribute to a new drug delivery system, not only for the control of infectious diseases but for various other diseases as well. In recent years, several studies have emphasized its application in infectious diseases, presenting better alternatives for the treatment of fungal infections.

Enhanced oral bioavailability and gastroprotective effect of ibuprofen through mixed polymer-lipid nanoparticles

Objectives: The aim of this study was to design and formulate mixed polymer-lipid nanoparticles (PLNs) for the delivery of ibuprofen. Methods: The mixed PLNs were prepared by a single modified emulsification solvent evaporation method. Key findings: Core-shell-shaped mixed PLNs were successfully prepared, with sizes in the nano range (193.3 ± 0.70 to 795.8 ± 0.70 nm) and ζ potential (-26.8 ± 0.45 to -42.8 ± 0.30 mV). Entrapment efficiency ranged from 80.3 to 93.6%. Conclusions: Pharmacokinetic parameters showed great improvement in C_max and T_max of ibuprofen from the formulation PLNs8 compared with the respective Brufen^® and pure drugs, indicating improvement in bioavailability of the drug.

Emerging Role of Hydrogels in Drug Delivery Systems, Tissue Engineering and Wound Management

The popularity of hydrogels as biomaterials lies in their tunable physical properties, ability to encapsulate small molecules and macromolecular drugs, water holding capacity, flexibility, and controllable degradability. Functionalization strategies to overcome the deficiencies of conventional hydrogels and expand the role of advanced hydrogels such as DNA hydrogels are extensively discussed in this review. Different types of cross-linking techniques, materials utilized, procedures, advantages, and disadvantages covering hydrogels are tabulated. The application of hydrogels, particularly in buccal, oral, vaginal, and transdermal drug delivery systems, are described. The review also focuses on composite hydrogels with enhanced properties that are being developed to meet the diverse demand of wound dressing materials. The unique advantages of hydrogel nanoparticles in targeted and intracellular delivery of various therapeutic agents are explained. Furthermore, different types of hydrogel-based materials utilized for tissue engineering applications and fabrication of contact lens are discussed. The article also provides an overview of selected examples of commercial products launched particularly in the area of oral and ocular drug delivery systems and wound dressing materials. Hydrogels can be prepared with a wide variety of properties, achieving biostable, bioresorbable, and biodegradable polymer matrices, whose mechanical properties and degree of swelling are tailored with a specific application. These unique features give them a promising future in the fields of drug delivery systems and applied biomedicine.

Recent Advances in Oral Nano-Antibiotics for Bacterial Infection Therapy

Bacterial infections are the main infectious diseases and cause of death worldwide. Antibiotics are used to treat various infections ranging from minor to life-threatening ones. The dominant route to administer antibiotics is through oral delivery and subsequent gastrointestinal tract (GIT) absorption. However, the delivery efficiency is limited by many factors such as low drug solubility and/or permeability, gastrointestinal instability, and low antibacterial activity. Nanotechnology has emerged as a novel and efficient tool for targeting drug delivery, and a number of promising nanotherapeutic strategies have been widely explored to overcome these obstacles. In this review, we explore published studies to provide a comprehensive understanding of the recent progress in the area of orally deliverable nano-antibiotic formulations. The first part of this article discusses the functions and underlying mechanisms by which nanomedicines increase the oral absorption of antibiotics. The second part focuses on the classification of oral nano-antibiotics and summarizes the advantages, disadvantages and applications of nanoformulations including lipid, polymer, nanosuspension, carbon nanotubes and mesoporous silica nanoparticles in oral delivery of antibiotics. Lastly, the challenges and future perspective of oral nano-antibiotics for infection disease therapy are discussed. Overall, nanomedicines designed for oral drug delivery system have demonstrated the potential for the improvement and optimization of currently available antibiotic therapies.

Amphotericin B loaded ethyl cellulose nanoparticles with magnified oral bioavailability for safe and effective treatment of fungal infection

Amphotericin B is a gold standard drug used in various fungal and parasitic infection treatment. Most of the marketed formulations are administered intravenously, but show dose-dependent adverse effects i.e., nephrotoxicity and hemolysis. Oral route eliminates the toxic concern but exhibits poor bioavailability. Therefore, ethylcellulose nanoparticles (EC-NPs) have been used for magnified oral delivery of AmB, where EC provides gastrointestinal stability. These nanoparticles were synthesized by high-pressure emulsification solvent evaporation (HPESE) method and evaluated for in vitro and in vivo studies. This method yields small, monodisperse AmB-EC-NPs along with smooth surface morphology and improved encapsulation efficiency. The developed formulation showed a sustained release pattern following Higuchi diffusion kinetics along with gastric and storage stability. Aggregation study revealed that AmB was present in its monomeric form inside the biocompatible EC matrix. The antifungal result demonstrated that the MIC of AmB-EC-NPs was reduced ∼1/3rd than AmB and Fungizone® at 24 h whereas it was observed ∼1/8th at 48 h. in vivo pharmacokinetic analysis demonstrated 1.3-fold higher AUC than Fungizone® even at a 4.5-time lesser dose via the oral route and a ∼15-fold rise in the bioavailability in contrast to the native AmB. The hemolytic study revealed that the developed formulation exhibited 8-fold lesser hemolysis than Fungizone®. Furthermore, the biosafety profile of AmB-EC-NPs was ensured by the significantly lesser level of blood urea nitrogen and plasma creatinine along with the normal pattern of renal tubules in comparison to AmB and Fungizone®. In conclusion, the results stipulated that the AmB-EC-NPs could be effective, viable and a better alternative to currently existing iv formulations, for magnified oral delivery of AmB in the treatment of fungal infection without associated adverse effects.

Red-Emissive Guanylated Polyene-Functionalized Carbon Dots Arm Oral Epithelia against Invasive Fungal Infections

Oral candidiasis as a highly prevalent and recurrent infection in medically compromised individuals is mainly caused by the opportunistic fungal pathogen Candida albicans. This epithelial infection, if not controlled effectively, can progress to life-threatening systemic conditions and complications. The efficacy of current frontline antifungals is limited due to their poor bioavailability and systemic toxicity. As such, an efficient intervention is essential for controlling disease progression and recurrence. Herein, a theranostic nanoplatform (CD-Gu⁺-AmB) was developed to track the penetration of antifungals and perturb the invasion of C. albicans at oral epithelial tissues, via decorating the homemade red-emissive carbon dots (CD) with positively charged guanidine groups (Gu⁺) followed by conjugation with antifungal polyene (amphotericin B, AmB) in a reacting site-controllable manner. The generated CD-Gu⁺-AmB favorably gathered within the Candida cells and exhibited potent antifungal effects in both planktonic and biofilm forms. It selectively accumulated in the nuclei of human oral keratinocytes and exhibited undetectable toxicity to the host cells. Moreover, we reported for the first time the penetration and exfoliation profiles of CD in a three-dimensional organotypic model of human oral epithelial tissues, demonstrating that the extra- and intracellular accumulation of CD-Gu⁺-AmB effectively resisted the invasion of C. albicans by forming a "shielding" layer throughout the entire tissue. This study establishes a multifunctional CD-based theranostic nanoplatform functioning as a traceable and topically applied antifungal to arm oral epithelia, thereby shedding light on early intervention of mucosal candidiasis for oral and general health.

Increased Efficacy of Oral Fixed-Dose Combination of Amphotericin B and AHCC® Natural Adjuvant against Aspergillosis

Invasive pulmonary aspergillosis represents one of the most serious fungal infections among immunocompromised patients. In this study, we aimed to analyze the in vivo efficacy of prophylactic oral amphotericin B (AMB) encapsulated in modified chitosan-nanoparticles (Nanomerics’ Molecular Envelope Technology (MET)) supplemented with a standardized extract of cultured Lentinula edodes mycelia (AHCC^®) in a murine model of pulmonary aspergillosis. We determined fungal burden and survival of mice and additionally, we carried out a cytokine analysis in an attempt to understand the immunomodulation of the extract. Our results evidenced equivalent efficacy between orally administered AMB-MET and the intravenous liposomal AMB marketed formulation. Addition of the AHCC^® supplement significantly improved efficacy in terms of burden reduction and survival increase of both oral and intravenous AMB therapies compared to the untreated control group. Moreover, a protective effect of the extract was observed in terms of weight loss. Regarding the cytokine profiles, the Th1 immune response was stimulated in treated animals when compared to the control group. This response was marked by an enhancement in the MCP-1, GM-CSF, VEGF, RANTES and IL-17 levels and a decrease in the IL-6, a biomarker related to the severity of the infection.

Exploiting knowledge on pharmacodynamics-pharmacokinetics for accelerated anti-leishmanial drug discovery/development

Introduction: Being on the top list of neglected tropical diseases, leishmaniasis has been marked for elimination by 2020. In the light of small armamentarium of drugs and their associated drawbacks, the understanding of pharmacodynamics and/or pharmacokinetics becomes a priority to achieve and sustain disease elimination. Areas covered: The authors have looked into pharmacological aspects of existing and emerging drugs for treatment of leishmaniasis. An in-depth understanding of pharmacodynamics and pharmacokinetics (PKPD) provides a rationale for drug designing and optimizing the treatment strategies. It forms a key to prevent drug resistance and avoid drug-associated adverse effects. The authors have compiled the researches on the PKPD of different anti-leishmanial formulations that have the potential for improved and/or effective disease intervention. Expert opinion: Understanding the pharmacological aspects of drugs forms the basis for the clinical application of novel drugs. Tailoring drug dosage and individualized treatment can avoid the adverse events and bridge gap between the in vitro models and their clinical application. An integrated approach, with pragmatic use of technological advances can improve phenotypic screening and physiochemical properties of novel drugs. Concomitantly, this can serve to improve clinical efficacies, reduce the incidence of relapse and accelerate the drug discovery/development process for leishmaniasis elimination.

Design and Toxicity Evaluation of Novel Fatty Acid-Amino Acid-Based Biocompatible Surfactants

Surfactants occupy an important place owing to their wide application, but primarily compromised due to its toxicity issues. This raises the need for exploration of newer surfactants with increased biocompatibility. Novel fatty acid- and amino acid-based surfactants were prepared using standard carbodiimide chemistry. Pyrene assay was implemented to confirm the amphiphilic nature of the surfactants and to calculate their CMC (critical micellar concentration). In vitro hemolytic and cell culture study in MCF-7 and HEK cell line were done to check the in vitro biocompatibility of the developed surfactants in comparison to marketed surfactants Triton X-100 and Tween ® 80. In vivo biocompatibility test in female Swiss albino mice was carried out in comparison to marketed surfactants with respect to serum markers, organ histology, and RBC morphology. Surfactant synthesis provided more than 60% yield in all the conjugates. Pyrene assay concluded the amphiphilic nature of the surfactants with lowest CMC of 0.083% w/v in the case of stearic acid and valine conjugate. In vitro hemolytic and cell culture study depicted highest biocompatibility in vitro as compared to marketed surfactants. Similar results were obtained in in vivo biocompatibility with respect to AST (aspartate transaminase), ALT (alanine transaminase), BUN (blood urea nitrogen), and creatinine serum levels and histology of spleen, liver, and kidney in comparison to marketed surfactants Triton X-100 and Tween ® 80. The developed surfactant also depicted least RBC morphology changes in vivo. Stearic acid valine conjugate thus depicted potential for further application in formulation development replacing the commercially available surfactants.

An update on polymer-lipid hybrid systems for improving oral drug delivery

INTRODUCTION

A promising approach that has recently emerged to overcome the complex biobarriers and interrelated challenges associated with oral drug absorption is to combine the benefits of polymeric and lipid-based nanocarriers within one hybrid system. This multifaceted formulation strategy has given rise to a plethora of polymer-lipid hybrid (PLH) systems with varying nanostructures and biological activities, all of which have demonstrated the ability to improve the biopharmaceutical performance of a wide range of challenging therapeutics.

AREAS COVERED

The multitude of polymers that can be combined with lipids to exert a synergistic effect for oral drug delivery have been identified, reviewed and critically evaluated. Specific focus is attributed to preclinical studies performed within the past 5 years that have elucidated the role and mechanism of the polymer phase in altering the oral absorption of encapsulated therapeutics.

EXPERT OPINION

The potential of PLH systems has been clearly identified; however, improved understanding of the structure-activity relationship between PLH systems and oral absorption is fundamental for translating this promising delivery approach into a clinically relevant formulation. Advancing research within this field to identify optimal polymer, lipid combinations and engineering conditions for specific therapeutics are therefore encouraged.

Potential of Nanoparticles in Combating Candida Infections

Aims:

The aim of this review is to survey the recent progress made in developing the nanoparticles as antifungal agents especially the nano-based formulations being exploited for the management of Candida infections.

Discussion:

In the last few decades, there has been many-fold increase in fungal infections including candidiasis due to the increased number of immunocompromised patients worldwide. The efficacy of available antifungal drugs is limited due to its associated toxicity and drug resistance in clinical strains. The recent advancements in nanobiotechnology have opened a new hope for the development of novel formulations with enhanced therapeutic efficacy, improved drug delivery and low toxicity.

Conclusion:

Metal nanoparticles have shown to possess promising in vitro antifungal activities and could be effectively used for enhanced and targeted delivery of conventionally used drugs. The synergistic interaction between nanoparticles and various antifungal agents have also been reported with enhanced antifungal activity.

Solid nanoparticles for oral antimicrobial drug delivery: a review

Most microbial infectious diseases can be treated successfully with the remarkable array of antimicrobials current available; however, antimicrobial resistance, adverse effects, and the high cost of antimicrobials are crucial health challenges worldwide. One of the common efforts in addressing this issue lies in improving the existing antibacterial delivery systems. Solid nanoparticles (SNPs) have been widely used as promising strategies to overcome these challenges. In addition, oral delivery is the most common method of drug administration with high levels of patient acceptance. Formulation into NPs can improve drug stability in the harsh gastrointestinal (GI) tract environment, providing opportunities for targeting specific sites in the GI tract, increasing drug solubility and bioavailability, and providing sustained release in the GI tract. Here, we discuss SNPs for the oral delivery of antimicrobials, including solid lipid NPs (SLNs), polymeric NPs (PNs), mesoporous silica NPs (MSNs) and hybrid NPs (HNs). We also discussed about the role of nanotechnology in IV to oral antimicrobial therapy development as well as challenges, clinical transformation, and limitations of SNPs for oral antimicrobial drug delivery.

Lipid and TPGS based novel core-shell type nanocapsular sustained release system of methotrexate for intravenous application

Core shell nanocapsules present an interesting system for attaining high loading of drug. In an attempt, lipid and TPGS based novel core-shell nanocapsule were prepared to achieve high drug loading with sustained release of model hydrophilic drug methotrexate (MTX). Antisolvent nanoprecipitation was utilized for the formulation of nanoparticles. Optimized formulation depicted 223.6 ± 24.1 nm particle size, 0.243 ± 0.034 PDI, zeta potential -2.07 ± 0.51 mV and 15.03 ± 1.92%drug loading. In vitro release showed biphasic release for 12 h with initial burst phase followed by sustained release phase. Haemolytic study on RBCs revealed haemocompatible nature of MTX-TPGS nanoparticles compared to Biotrexate^® (Zydus). In vitro cell culture studies depicted 3 folds and 2.66 folds increase in cellular uptake of MTX at 10 μg/ml and 15 μg/ml respectively for developed nanoparticles with 3.81 folds decrease in IC₅₀ value as compared to Biotrexate^®. Higher apoptosis and increased lysosomal membrane permeability were also depicted by MTX-TPGS nanoparticles. 2.45 folds increase in AUC and 3.68 folds increase in T_1/2 was achieved in pharmacokinetic study. Significant reduction in tumor burden and serum biochemical parameters depicted efficacy and safety respectively of the formulation as compared to Biotrexate^®. RBCs morphology was retained after MTX-TPGS exposure proving its haemocompatibility in vivo.

Preparation and Characterization of Spherical Amorphous Solid Dispersion with Amphotericin B

In the present study, new polymer microspheres of amphotericin B (AmB) were prepared by a spray drying technique using cyclodextrin polymers (Poly-CD) to improve the solubility and dissolution of AmB, to prevent in vivo toxic AmB aggregations. Formulations were characterized through scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermal analysis, Raman spectroscopy, particle size, drug purity test and in vitro release studies. The analysis indicated that the chemical structure of AmB remained unchanged in the amorphous solid dispersion, but the structure was changed from crystalline to amorphous. AmB was completely release from such optimized formulations in dissolution media in 40 min. This work may contribute to a new generation of spherical amorphous solid dispersion using a cyclodextrin polymer, which has implications for the possibility of drug development for oral utilization or as powder aerosols for pulmonary administration.

Nano-lipid Complex of Rutin: Development, Characterisation and In Vivo Investigation of Hepatoprotective, Antioxidant Activity and Bioavailability Study in Rats

The current study was aimed to develop an amphiphilic drug-lipid nano-complex of rutin:egg phosphatidylcholine (EPC) to enhance its poor absorption and bioavailability, and investigated the impact of the complex on hepatoprotective and antioxidant activity. Rutin nano-complexes were prepared by solvent evaporation, salting out and lyophilisation methods and compared for the complex formation. For the selected lyophilisation method, principal solvent DMSO, co-solvent (t-butyl alcohol) and rutin:EPC ratios (1:1, 1:2 and 1:3) were selected after optimisation. The properties of the nano-complexes such as complexation, thermal behaviour, surface morphology, molecular crystallinity, particle size, zeta potential, drug content, solubility, in vitro stability study, in vitro drug release, in vitro and in vivo antioxidant study, in vivo hepatoprotective activity and oral bioavailability/pharmacokinetic studies were investigated. Rutin nano-complexes were developed successfully via the lyophilisation method and found to be in nanometric range. Rutin nano-complexes significantly improved the solubility and in vitro drug release, and kinetic studies confirmed the diffusion-controlled release of the drug from the formulation. The nano-complex showed better antioxidant activity in vitro and exhibited well in vitro stability in different pH media. The in vivo study showed better hepatoprotective activity of the formulation compared to pure rutin at the same dose levels with improved oral bioavailability. Carbon tetrachloride (CCl₄)-treated animals (group II) failed to restore the normal levels of serum hepatic marker enzymes and liver antioxidant enzyme compared to the nano-complex-treated animals. The results obtained from solubility, hepatoprotective activity and oral bioavailability studies proved the better efficacy of the nano-complex compared to the pure drug.

Amphotericin B Loaded Chitosan Nanoparticles: Implication of Bile Salt Stabilization on Gastrointestinal Stability, Permeability and Oral Bioavailability

Through current investigation, we presented a lucrative way to formulate amphotericin B loaded bile salt stabilized carbohydrate polymer i.e. chitosan nanoparticles (NPs) for enhancing gastrointestinal stability of NPs thereby increasing the oral bioavailability of the drug. NPs were prepared using ionic gelation method, and stabilized using bile salt to provide gastric pH stability to chitosan NPs. NPs were optimized on different parameters such as particle size, encapsulation efficiency and estimated for their in vitro and in vivo performance. Developed NPs presented a higher stability in gastrointestinal milieu, reduced haemolytic toxicity and significantly higher uptake in Caco-2 cell lines followed by increased bioavailability as compared to naive drug, marketed formulation i.e. Fungizone® and uncoated chitosan NPs. Biochemical parameters and histology further substantiated the lower toxicity. In nutshell, the present research explored the bioadhesive and higher uptake potential of cationic carbohydrate polymer at the same time along with bile salts for stabilization of NPs in gastric milieu.

Co-delivery of docetaxel and gemcitabine by anacardic acid modified self-assembled albumin nanoparticles for effective breast cancer management

In the present study, we have modified bovine serum albumin (BSA) by covalently conjugating with anacardic acid (AA) and gemcitabine (GEM) and further used for development of docetaxel (DTX) loaded nanoparticles (AA-GEM-BSA NPs). AA is supposed to provide tumor targeting through VEGF receptors overexpressed in tumors, while the combination of GEM and DTX is supposed to provide synergistic activity by targeting multiple pathways. The conjugate was synthesized via carbodiimide chemistry and characterized by ¹H NMR, FTIR, MALDI-TOF and elemental analysis. Conformational changes owing to conjugation of AA and GEM were estimated via fluorescence, Raman and CD spectroscopy, while changes in physiochemical properties were studied by differential scanning calorimetry (DSC), thermogravimetry (TGA) and contact angle goniometry (CAG). Synthesized conjugate was further transformed into DTX loaded NPs and freeze dried. Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) demonstrated formation of spherical NPs having particle size, 163 ± 8 nm, PDI, 0.13 ± 0.09 and ZP, -27 ± 1 mV. Cellular uptake in MCF-7 and MDA-MB-231 revealed hNTs, OATP1B3 independent, clathrin mediated internalization followed via nuclear co-localization of C-6 loaded AA-GEM-BSA NPs, responsible for significantly higher apoptosis index. Pharmacokinetic profile of DTX loaded AA-GEM-BSA NPs revealed 6.12 and 3.27-fold and 6.28 and 8.9-fold higher AUC and T_1/2 values of DTX and GEM as compared to Taxotere® and Gemzar®, respectively. Interestingly, the developed NPs were found safe with no marked effect on RBCs, lower hepato and nephro toxicity. Data in hand suggest promising potential of developed NPs in ameliorating the pharmacokinetic and therapeutic profile of combinatorial regimen of DTX and GEM.

STATEMENT OF SIGNIFICANCE

The present report is the original state of art technology to selectively target dual drug (DTX and GEM) loaded BSA NPs via exploring tumor targeting potential of AA, having high affinity towards VEGF receptors (angiogenesis marker) overexpressed in tumor. The AA and GEM bio-conjugated BSA was synthesized and further used to develop DTX loaded nanoparticles (AA-GEM-BSA NPs). The optimized NPs were further evaluated via extensive in vitro and in vivo studies, demonstrating ameliorated cellular uptake, pharmacokinetic and toxicity profile of drugs. Conclusively, DTX loaded AA-GEM-BSA NPs, holds promising potential in increasing the therapeutic efficiency of drugs and overcoming solvent and drug mediated side effects and can be explored further as a scalable platform technology for difficult to deliver drugs.

Lyotropic Liquid Crystalline Nanoparticles of Amphotericin B: Implication of Phytantriol and Glyceryl Monooleate on Bioavailability Enhancement

Implication of different dietary specific lipids such as phytantriol (PT) and glyceryl monooleate (GMO) on enhancing the oral bioavailability of amphotericin B (AmB) was examined. Liquid crystalline nanoparticles (LCNPs) were prepared using hydrotrope method, followed by in vitro characterization, Caco-2 cell monolayer uptake, and in vivo pharmacokinetic and toxicity evaluation. Optimized AmB-LCNPs displayed small particle size (< 210 nm) with a narrow distribution (~ 0.2), sustained drug release and high gastrointestinal stability, and reduced hemolytic toxicity. PLCNPs presented slower release, i.e., ~ 80% as compared to ~ 90% release in case of GLCNPs after 120 h. Significantly higher uptake in Caco-2 monolayer substantiated the role of LCNPs in increasing the intestinal permeability followed by increased drug titer in plasma. Pharmacokinetic studies demonstrated potential of PT in enhancing the bioavailability (approximately sixfold) w.r.t. of its native counterpart with reduced nephrotoxicity as presented by reduced nephrotoxicity biomarkers and histology studies. These studies established usefulness of PLCNPs over GLCNPs and plain drug. It can be concluded that acid-resistant lipid, PT, can be utilized efficiently as an alternate lipid for the preparation of LCNPs to enhance bioavailability and to reduce nephrotoxicity of the drug as compared to other frequently used lipid, i.e., GMO.

Lipid-polymer hybrid nanocarriers for delivering cancer therapeutics

Cancer remained a major cause of death providing diversified challenges in terms of treatment including non-specific toxicity, chemoresistance and relapse. Nanotechnology- based delivery systems grabbed tremendous attention for delivering cancer therapeutics as they provide benefits including controlled drug release, improved biological half-life, reduced toxicity and targeted delivery. Majority of the nanocarriers consists of either a polymer or a lipid component along with other excipients to stabilize the colloidal system. Lipid-based systems provide advantages like better entrapment efficiency, scalability and low- cost raw materials, however, suffer from limitations including instability, a burst release of the drug, and limited surface functionalization. On the other hand, polymeric systems provide an excellent diversity of chemical modifications, stability, controlled release, however limited drug loading capacities and scale up limit their use. Hybrid nanocarriers consisting of lipid and polymer were able to overcome some of these disadvantages while retaining the advantages of both the systems. Designing a stable lipid-polymer hybrid system requires a thorough understanding of the material properties and their behavior in in vitro and in vivo environments. This review highlights the current status and future prospects of lipid-polymer hybrid systems with a particular focus on cancer nanotherapeutics.