Chitosan-tailored lipidic nanoconstructs of Fusidic acid as promising vehicle for wound infections: An explorative study

Strategic development of aceclofenac loaded organosomes for topical application: An explorative ex-vivo and in-vivo investigation for arthritis

Present study intends to develop aceclofenac-encapsulated organosomes (OS), which consist of phospholipids coupled with a combination of organic solvents, for the management of arthritis. The formulation was characterized and tested for efficacy using formalin-induced hyperalgesia, air pouch, and CFA-induced arthritic rat models. OS system exhibited spherical dimension, nanometric size with low PDI (278.3 ± 12.21 nm; 0.145), zeta potential (-24.56 ± 7.53 mV), drug entrapment (85.62 ± 7.2 %) and vesicles count (4.2x104 mm3). The gelled OS formulation demonstrated increased drug permeability and accumulation rate (51.77 ± 7.1 % and 396.19 ± 59.21 µg/cm2) compared to the MKT product (102.93 ± 13.78 µg/cm2 and 16.14 ± 4.3 %). Dermatokinetic assessments exhibited significantly higher drug levels in dermal layers compared to MKT product (p < 0.001), and CLSM studies further supported the OS system's deeper penetration. The results of arthritic index significantly better (9 times) in the OS-treated group than the MKT product. OS system treatment significantly reduced biochemicals and cytokines levels, such as CRP, ESR, TLC, lymphocytes, TNF-α, IL-6, and IL-1β to levels of the control group (p < 0.001). Pseudoplastic behaviour of the developed product was indicated by the rheological results, and it also demonstrated biocompatibility through skin compliance studies. Based on the current findings, it appears that OS may be a better choice for managing arthritis and related inflammations.

Albumin as a functional carrier solubilizing and facilitating fusidic acid transmembrane delivery into Gram-negative bacteria

Reversing the bacterial resistance is of great significance and importance. Fusidic acid (FA) is commonly effective against Gram-positive bacterial infections, but most Gram-negative bacteria have intrinsic resistance to FA, primarily due to the strong cell membrane-FA interactions, which highly inhibit the intracellular transport of FA. Herein, we use albumin (bovine serum albumin, BSA) as a bifunctional carrier to solubilize FA and facilitate its transmembrane delivery into Gram-negative bacterial cells. The water solubility of FA is significantly enhanced from 11.87 to 442.20 μg/mL by 5 mg/mL BSA after forming FA-BSA complex. Furthermore, FA-BSA (200 μg/mL) causes 99.96 % viability loss to the model pathogen E. coli upon incubation for 3 h, while free FA or BSA alone shows little activity. Elongation of E. coli cells after treated by FA-BSA is demonstrated by SEM, and the transmembrane transport of FA-BSA is demonstrated by CLSM. Interestingly, increasing the BSA amount substantially reduce the antibacterial activity of FA-BSA, implying an albumin-based transmembrane delivery mechanism may exist. This is the first report regarding successfully reversing the intrinsic resistance of Gram-negative bacteria to FA in the form of FA-BSA. The ready availability of albumin and the simple preparation allows FA-BSA to have great potentials for clinical use.

Development of Lipid Polymer Hybrid Nanoparticles of Abietic Acid: Optimization, In-Vitro and Preclinical Evaluation

The objective of the current research was to develop abietic acid (AA)-loaded hybrid polymeric nanoparticles (HNPs) for anti-inflammatory and antioxidant activity after oral administration. AAHNPs were developed by microinjection technique and optimized by 3-factor 3-level Box-Behnken design. The AAHNPs were evaluated for morphology, FTIR, X-ray diffraction, in-vitro release, ex-vivo permeation, in-vitro antioxidant, and in-vivo anti-inflammatory activity. The optimized AAHNPs (AAHNPsopt) displayed 384.5 ± 6.36nm of PS, 0.376 of PDI, 23.0 mV of ZP, and 80.01 ± 1.89% of EE. FTIR and X-ray diffraction study results revealed that AA was encapsulated into a HNPs matrix. The AAHNPsopt showed significant (P < 0.05) high and sustained release of AA (86.72 ± 4.92%) than pure AA (29.87 ± 3.11%) in 24h. AAHNPsopt showed an initial fast release of AA (20.12 ± 3.07% in 2h), which succeeded in reaching the therapeutic concentration. The AAHNPsopt showed 2.49-fold higher ex-vivo gut permeation flux than pure AA due to the presence of lipid and surfactant. The AAHNPsopt exhibited significantly (P < 0.05, P < 0.01, P < 0.001) higher antioxidant activity as compared to pure AA at each concentration. AAHNPsopt formulation displayed a significantly (P < 0.05) higher anti-inflammatory effect (21.51 ± 2.23% swelling) as compared to pure AA (46.51 ± 1.74% swelling). From the in-vitro and in-vivo finding, it was concluded that HNPs might be a suitable carrier for the improvement of the therapeutic efficacy of the drug.

Dual Drug-Loaded Coaxial Nanofiber Dressings for the Treatment of Diabetic Foot Ulcer

Introduction

Diabetes mellitus is frequently associated with foot ulcers, which pose significant health risks and complications. Impaired wound healing in diabetic patients is attributed to multiple factors, including hyperglycemia, neuropathy, chronic inflammation, oxidative damage, and decreased vascularization.

Rationale

To address these challenges, this project aims to develop bioactive, fast-dissolving nanofiber dressings composed of polyvinylpyrrolidone loaded with a combination of an antibiotic (moxifloxacin or fusidic acid) and anti-inflammatory drug (pirfenidone) using electrospinning technique to prevent the bacterial growth, reduce inflammation, and expedite wound healing in diabetic wounds.

Results

The fabricated drug-loaded fibers exhibited diameters of 443 ± 67 nm for moxifloxacin/pirfenidone nanofibers and 488 ± 92 nm for fusidic acid/pirfenidone nanofibers. The encapsulation efficiency, drug loading and drug release studies for the moxifloxacin/pirfenidone nanofibers were found to be 70 ± 3% and 20 ± 1 µg/mg, respectively, for moxifloxacin, and 96 ± 6% and 28 ± 2 µg/mg, respectively, for pirfenidone, with a complete release of both drugs within 24 hours, whereas the fusidic acid/pirfenidone nanofibers were found to be 95 ± 6% and 28 ± 2 µg/mg, respectively, for fusidic acid and 102 ± 5% and 30 ± 2 µg/mg, respectively, for pirfenidone, with a release rate of 66% for fusidic acid and 80%, for pirfenidone after 24 hours. The efficacy of the prepared nanofiber formulations in accelerating wound healing was evaluated using an induced diabetic rat model. All tested formulations showed an earlier complete closure of the wound compared to the controls, which was also supported by the histopathological assessment. Notably, the combination of fusidic acid and pirfenidone nanofibers demonstrated wound healing acceleration on day 8, earlier than all tested groups.

Conclusion

These findings highlight the potential of the drug-loaded nanofibrous system as a promising medicated wound dressing for diabetic foot applications.

Topical Nanotherapeutics for Treating MRSA-Associated Skin and Soft Tissue Infection (SSTIs)

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) imposes a major challenge for the treatment of infectious diseases with existing antibiotics. MRSA associated with superficial skin and soft tissue infections (SSTIs) is one of them, affecting the skin's superficial layers, and it includes impetigo, folliculitis, cellulitis, furuncles, abscesses, surgical site infections, etc. The efficient care of superficial SSTIs caused by MRSA necessitates local administration of antibiotics, because oral antibiotics does not produce the required concentration at the local site. The topical administration of nanocarriers has been emerging in the area of drug delivery due to its advantages over conventional topical formulation. It enhances the solubility and permeation of the antibiotics into deeper layer of the skin. Apart from this, antibiotic resistance is something that needs to be combated on multiple fronts, and antibiotics encapsulated in nanocarriers help to do so by increasing the therapeutic efficacy in a number of different ways. The current review provides an overview of the resistance mechanism in S. aureus as well as various nanocarriers reported for the effective management of MRSA-associated superficial SSTIs.

Dissolvable sodium alginate-based antibacterial wound dressing patches: Design, characterization, and in vitro biological studies

The treatment of infected wounds in patients with highly sensitive skin is challenging. Some of the available wound dressings cause further skin tear and bleeding upon removal thereby hindering the healing process. In this study, dissolvable antibacterial wound dressing patches loaded with cephalexin monohydrate were prepared from different amounts of sodium alginate (SA) and carboxymethyl cellulose (CMC) by the solvent casting evaporation technique. The patches displayed good tensile strength (3.83-13.83 MPa), appropriate thickness (0.09 to 0.31 mm) and good flexibility (74-98 %) suitable for the skin. The patches displayed good biodegradability and low moisture uptake suitable to prevent microbial invasion on the wound dressings upon storage. The release profile of the drug from the patches was sustained in the range of 47-80 % for 48 h, revealing their capability to inhibit bacterial infection. The biological assay showed that the patches did not induce cytotoxic effects on HaCaT cells, revealing good biocompatibility. The antimicrobial effect of the patches on the different strains of bacteria used in the study was significant. The cell migration (66.7-74.3 %) to the scratched gap was promising revealing the patches' capability to promote wound closure. The results obtained show that the wound dressings are potential materials for the treatment of infected wounds.

The Use of Proteins, Lipids, and Carbohydrates in the Management of Wounds

Despite the fact that skin has a stronger potential to regenerate than other tissues, wounds have become a serious healthcare issue. Much effort has been focused on developing efficient therapeutical approaches, especially biological ones. This paper presents a comprehensive review on the wound healing process, the classification of wounds, and the particular characteristics of each phase of the repair process. We also highlight characteristics of the normal process and those involved in impaired wound healing, specifically in the case of infected wounds. The treatments discussed here include proteins, lipids, and carbohydrates. Proteins are important actors mediating interactions between cells and between them and the extracellular matrix, which are essential interactions for the healing process. Different strategies involving biopolymers, blends, nanotools, and immobilizing systems have been studied against infected wounds. Lipids of animal, mineral, and mainly vegetable origin have been used in the development of topical biocompatible formulations, since their healing, antimicrobial, and anti-inflammatory properties are interesting for wound healing. Vegetable oils, polymeric films, lipid nanoparticles, and lipid-based drug delivery systems have been reported as promising approaches in managing skin wounds. Carbohydrate-based formulations as blends, hydrogels, and nanocomposites, have also been reported as promising healing, antimicrobial, and modulatory agents for wound management.

Recent Advances in the Development of Lipid-, Metal-, Carbon-, and Polymer-Based Nanomaterials for Antibacterial Applications

Infections caused by multidrug-resistant (MDR) bacteria are becoming a serious threat to public health worldwide. With an ever-reducing pipeline of last-resort drugs further complicating the current dire situation arising due to antibiotic resistance, there has never been a greater urgency to attempt to discover potential new antibiotics. The use of nanotechnology, encompassing a broad range of organic and inorganic nanomaterials, offers promising solutions. Organic nanomaterials, including lipid-, polymer-, and carbon-based nanomaterials, have inherent antibacterial activity or can act as nanocarriers in delivering antibacterial agents. Nanocarriers, owing to the protection and enhanced bioavailability of the encapsulated drugs, have the ability to enable an increased concentration of a drug to be delivered to an infected site and reduce the associated toxicity elsewhere. On the other hand, inorganic metal-based nanomaterials exhibit multivalent antibacterial mechanisms that combat MDR bacteria effectively and reduce the occurrence of bacterial resistance. These nanomaterials have great potential for the prevention and treatment of MDR bacterial infection. Recent advances in the field of nanotechnology are enabling researchers to utilize nanomaterial building blocks in intriguing ways to create multi-functional nanocomposite materials. These nanocomposite materials, formed by lipid-, polymer-, carbon-, and metal-based nanomaterial building blocks, have opened a new avenue for researchers due to the unprecedented physiochemical properties and enhanced antibacterial activities being observed when compared to their mono-constituent parts. This review covers the latest advances of nanotechnologies used in the design and development of nano- and nanocomposite materials to fight MDR bacteria with different purposes. Our aim is to discuss and summarize these recently established nanomaterials and the respective nanocomposites, their current application, and challenges for use in applications treating MDR bacteria. In addition, we discuss the prospects for antimicrobial nanomaterials and look forward to further develop these materials, emphasizing their potential for clinical translation.

Harnessing Lipid Polymer Hybrid Nanoparticles for Enhanced Oral Bioavailability of Thymoquinone: In Vitro and In Vivo Assessments

The clinical application of phytochemicals such as thymoquinone (THQ) is restricted due to their limited aqueous solubility and oral bioavailability. Developing mucoadhesive nanocarriers to deliver these natural compounds might provide new hope to enhance their oral bioavailability. Herein, this investigation aimed to develop THQ-loaded lipid-polymer hybrid nanoparticles (THQ-LPHNPs) based on natural polymer chitosan. THQ-LPHNPs were fabricated by the nanoprecipitation technique and optimized by the 3-factor 3-level Box−Behnken design. The optimized LPHNPs represented excellent properties for ideal THQ delivery for oral administration. The optimized THQ-LPHNPs revealed the particles size (PS), polydispersity index (PDI), entrapment efficiency (%EE), and zeta potential (ZP) of <200 nm, <0.25, >85%, and >25 mV, respectively. THQ-LPHNPs represented excellent stability in the gastrointestinal milieu and storage stability in different environmental conditions. THQ-LPHNPs represented almost similar release profiles in both gastric as well as intestinal media with the initial fast release for 4 h and after that a sustained release up to 48 h. Further, the optimized THQ-LPHNPs represent excellent mucin binding efficiency (>70%). Cytotoxicity study revealed much better anti-breast cancer activity of THQ-LPHNPs compared with free THQ against MDA-MB-231 and MCF-7 breast cancer cells. Moreover, ex vivo experiments revealed more than three times higher permeation from the intestine after THQ-LPHNPs administration compared to the conventional THQ suspension. Furthermore, the THQ-LPHNPs showed 4.74-fold enhanced bioavailability after oral administration in comparison with the conventional THQ suspension. Therefore, from the above outcomes, mucoadhesive LPHNPs might be suitable nano-scale carriers for enhanced oral bioavailability and therapeutic efficacy of highly lipophilic phytochemicals such as THQ.

Development and characterization of niosomal gel of fusidic acid: in-vitro and ex-vivo approaches

Niosomes are multilamellar vesicles that efficiently deliver active substance into skin systemic circulation or skin layers. They are used in topical drug delivery system to enhance the skin permeation of active substance. So, the prime objective of this study was to develop a niosomal gel of fusidic acid to increase its skin permeation. Different formulations of niosomes of fusidic acid were designed by varying the cholesterol to surfactant ratio. Formulations containing fusidic acid, cholesterol, dihexadecyl pyridinium chloride, Span 60, or Tween 60 were prepared by thin film hydration method in rotary evaporator. The thin film formed in rotary flask was hydrated by phosphate buffer saline of pH 7.2. The niosomes formed were characterized through entrapment efficiency, size, polydispersity index (PDI), and zeta potential. The S3 formulation containing span 60 showed the highest entrapment efficiency (EE) of niosomes, so it was incorporated into Carbopol gel. Determination of pH, spreadability, rheological, and ex vivo permeation studies was conducted of niosomal gel. The results of ex vivo permeation studies showed high permeation of fusidic acid when gel was applied to an albino rat skin. According to the results and previous studies of niosomes, it can be concluded that niosomes enhanced the permeation of fusidic acid through the skin.

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.

Novel Formulation of Fusidic Acid Incorporated into a Myrrh-Oil-Based Nanoemulgel for the Enhancement of Skin Bacterial Infection Treatment

Fusidic acid (FA) is renowned as an effective bacteriostatic agent obtained from the fungus Fusidium coccineum, used for treating various eye and skin disorders. The objective of the present study was to develop, characterize, and evaluate the antibacterial activity of a novel FA nanoemulgel for topical skin application. Primarily, various fusidic acid nanoemulsion formulations were fabricated using different concentrations of myrrh essential oil, Tween 80 as a surfactant, and Transcutol® P as a co-surfactant. A Box−Behnken design was employed to select the optimized FA nanoemulsion formulation, based on the evaluated particle size and % of in vitro release as dependent variables. The optimized formula was incorporated within a hydrogel to obtain an FA nanoemulgel (FA-NEG) preparation. The formulated FA-NEG was evaluated for its visual appearance, pH, viscosity, and spreadability, compared to its corresponding prepared fusidic acid gel. In vitro release, kinetic study, and ex vivo drug permeation were implemented, followed by formulation stability testing. The FA-NEG exhibited a smooth and homogeneous appearance, pH value (6.61), viscosity (25,265 cP), and spreadability (33.6 mm), which were all good characteristics for appropriate topical application. A total of 59.3% of FA was released from the FA-NEG after 3 h. The ex vivo skin permeability of the FA-NEG was significantly enhanced by 3.10 ± 0.13-fold, showing SSTF of 111.2 ± 4.5 µg/cm2·h when compared to other formulations under investigation (p < 0.05). No irritation was observed upon applying the FA-NEG to animal skin. Eventually, it was revealed that the FA-NEG displayed improved antibacterial activity against a wide variety of bacteria when compared to its corresponding FA gel and marketed cream, indicating the prospective antibacterial effect of myrrh essential oil. In conclusion, the recommended formulation offers a promising antibacterial approach for skin infections.

Formulation and Evaluation of Apigenin-Loaded Hybrid Nanoparticles

Apigenin (AGN) is a potent phytochemical with strong antioxidant and anticancer potential. But its therapeutic efficacy is limited due to its high lipophilic characteristics. Therefore, the present investigation aimed to develop AGN-loaded polymer-lipid hybrid nanoparticles (AGN-PLHNPs). Herein, we successfully developed AGN-PLHNPs and optimized them by a 33-Box-Behnken de-sign. The poly (lactic-co-glycolic acid) (PLGA; coded as F1), phospholipon 90 G (PL-90G; coded as F2), and poloxamer 188 (P-188; coded as F3) were considered as the independent factors while particle size (PS; coded as R1), entrapment efficiency (%EE; R2), and cumulative drug release (%CDR; R3) were selected as dependent responses. The average PS, %EE, and %CDR of the AGN-PLHNPs were observed in the range of 101.93 nm to 175.26 nm, 58.35% to 81.14%, and 71.21% to 93.31%, respectively. The optimized AGN-PLHNPs revealed better homogeneity (poly-dispersity index < 0.2) and colloidal stability with high zeta potential (>25 mV). It also exhibited fast release in the initial 4 h after that sustained release up to 48 h of study. Moreover, the results of both DPPH as well as ABTS assays revealed significant improvement in the antioxidant activity. Furthermore, the optimized AGN-PLHNPs exhibited enhanced cytotoxicity efficacy against MCF-7 as well as MDA-MB-231 breast cancer cell lines.

Formulation of Piperine Nanoparticles: In Vitro Breast Cancer Cell Line and In Vivo Evaluation

Piperine (PPN), one of the most investigated phytochemicals, is known to have excellent therapeutic efficacy against a variety of ailments including breast cancer. However, its physicochemical properties such as poor aqueous solubility restrict its clinical application. Therefore, the present investigation was designed to develop PPN encapsulated lipid polymer hybrid nanoparticles (PPN-LPHNPs) to overcome the limitation. The developed PPN-LPHNPs were optimized by the three-factor, three-level Box−Behnken design (33-BBD). The optimized PPN-LPHNPs were then evaluated for their drug release profile, cytotoxicity assay against MDA-MB-231 and MCF-7 cells, and gastrointestinal stability as well as colloidal stability. In addition, the optimized PPN-LPHNPs were evaluated for ex vivo intestinal permeation and in vivo pharmacokinetic in albino Wistar rats. As per the results, the optimized PPN-LPHNPs showed a small average particles size of <160 nm with a low (<0.3) polydispersity index, and highly positive surface charge (>+20 mV). PPN-LPHNPs revealed excellent gastrointestinal as well as colloidal stability and sustained release profiles up to 24 h. Furthermore, PPN-LPHNPs revealed excellent cytotoxicity against both MDA-MB-231 and MCF-7 cancer cells compared to the free PPN. Moreover, animal studies revealed that the PPN-LPHNPs exhibited a 6.02- and 4.55-fold higher intestinal permeation and relative oral bioavailability, respectively, in comparison to the conventional PPN suspension. Thus, our developed LPHNPs present a strong potential for improved delivery of PPN.

Tertiary Nanosystem Composed of Graphene Quantum Dots, Levofloxacin and Silver Nitrate for Microbiological Control

BACKGROUND

Infectious diseases have the highest mortality rate in the world and these numbers are associated with scarce and/or ineffective diagnosis and bacterial resistance. Currently, with the development of new pharmaceutical formulations, nanotechnology is gaining prominence.

METHODS

Nanomicelles were produced by ultrasonication. The particle size and shape were evaluated by scanning electron microscopy and confirmed by dynamic light scattering, also thermogravimetric analysis was performed to evaluate the thermal stability. Finally, antibacterial activity has been performed.

RESULTS

The results showed that a rod-shaped nanosystem, with 316.1 nm and PDI of 0.243 was formed. The nanosystem was efficient against Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis subsp. spizizenii with MIC inferior to 0.98 and a synergistic effect between silver graphene quantum dots and levofloxacin was observed.

CONCLUSION

The nanosystem produced may rise as a promising agent against the bacterial threat, especially regarding bacterial resistance.

Span 80/TPGS modified lipid-coated chitosan nanocomplexes of acyclovir as a topical delivery system for viral skin infections

Acyclovir (ACR) is considered the gold standard drug for the treatment of skin viral infections caused by the herpes simplex or varicella-zoster virus. However, topical therapy with ACR is hindered by its poor skin penetrability, thus necessitating high doses and frequent administrations. This study was proposed to formulate a modified lipid-coated chitosan nanocomplexes (LCNCs) of acyclovir (ACR), containing span 80 and TPGS, to boost the dermal delivery of ACR and improve the therapeutic outcomes. LCNCs were formulated through a self-assembly method, and the statistical analysis and the optimization were performed via a general 2³ factorial design. Three formulation variables were selected; namely, the amount of chitosan (A), the amount of glyceryl monooleate (GMO) (B), and span 80: D-α-tocopheryl polyethylene glycol succinate (Vitamin ETPGSorTPGS) ratio (C). Four measured attributes were determined; viz., the particle size (PS) in nm, the polydispersity index (PDI), the zeta potential (ZP) in mV, and the entrapment efficiency percentages (EE%). The optimal formulation (LCNCs 8), formulated with 600 mg chitosan, 120 mg GMO, and 3:1 span 80: TPGS ratio, possessed PS of 177.50 ± 1.41 nm, PDI value of 0.28 ± 0.02, ZP of -10.70 ± 0.85 mV, and EE% of 77.20 ± 2.40 %, and was able to sustain ACR release over 24 h. Transmission electron microscopy displayed LCNCs architecture as a polymeric core of chitosan with a lipid coat of GMO, and the solid-state characterization results confirmed the dispersion of ACR in LCNCs. The ex vivo permeation study and the in vivo dermatokinetics profile verified the boosted accumulation of ACR in the skin via LCNCs, while the confocal laser scanning microscopy revealed the heightened penetrability of LCNCs. The topical application of LCNCs demonstrated a safe profile via the modified Draize test and histopathological examinations. Inclusively, ACR-loaded LCNCs could be a promising topical formulation with an advanced dermal delivery status for the treatment of skin viral infections.

Exemestane encapsulated polymer-lipid hybrid nanoparticles for improved efficacy against breast cancer: optimization,in vitrocharacterization and cell culture studies

Polymer-lipid hybrid nanoparticles (PLHNPs) are novel nanoplatforms for the effective delivery of a lipophilic drug in the management of a variety of solid tumors. The present work was designed to develop exemestane (EXE) encapsulated D-alpha-tocopheryl polyethylene glycol succinate (TPGS) based PLHNPs (EXE-TPGS-PLHNPs) for controlled delivery of EXE for breast cancer management. EXE-TPGS-PLHNPs were formulated by single-step nano-precipitation technique and statistically optimized by a 3³Box-Behnken design using Design expert^®software. The polycaprolactone (PCL;X₁), phospholipon 90 G (PL-90G;X₂), and surfactant (X₃) were selected as independent factors while particles size (PS;Y₁), polydispersity index (PDI;Y₂), and %entrapment efficiency (%EE;Y₃) were chosen as dependent factors. The average PS, PDI, and %EE of the optimized EXE-TPGS-PLHNPs was observed to be 136.37 ± 3.27 nm, 0.110 ± 0.013, and 88.56 ± 2.15% respectively. The physical state of entrapped EXE was further validated by Fourier-transform infrared spectroscopy, differential scanning calorimetry, and powder x-ray diffraction that revealed complete encapsulation of EXE in the hybrid matrix of PLHNPs with no sign of significant interaction between drug and excipients.In vitrorelease study in simulated gastrointestinal fluids revealed initial fast release for 2 h after that controlled release profile up to 24 h of study. Moreover, optimized EXE-TPGS-PLHNPs exhibited excellent stability in gastrointestinal fluids as well as colloidal stability in different storage concentrations. Furthermore, EXE-TPGS-PLHNPs exhibited distinctively higher cellular uptake and time and dose-dependent cytotoxicity against MCF-7 breast tumor cells compared to EXE-PLHNPs without TPGS and free EXE. The obtained results suggested that EXE-TPGS-PLHNPs can be a promising platform for the controlled delivery of EXE for the effective treatment of breast cancer.

Applications of Nanosized-Lipid-Based Drug Delivery Systems in Wound Care

Impaired wound healing is an encumbering public health issue that increases the demand for developing new therapies in order to minimize health costs and enhance treatment efficacy. Available conventional therapies are still unable to maximize their potential in penetrating the skin at the target site and accelerating the healing process. Nanotechnology exhibits an excellent opportunity to enrich currently available medical treatments, enhance standard care and manage wounds. It is a promising approach, able to address issues such as the permeability and bioavailability of drugs with reduced stability or low water solubility. This paper focuses on nanosized-lipid-based drug delivery systems, describing their numerous applications in managing skin wounds. We also highlight the relationship between the physicochemical characteristics of nanosized, lipid-based drug delivery systems and their impact on the wound-healing process. Different types of nanosized-lipid-based drug delivery systems, such as vesicular systems and lipid nanoparticles, demonstrated better applicability and enhanced skin penetration in wound healing therapy compared with conventional treatments. Moreover, an improved chemically and physically stable drug delivery system, with increased drug loading capacity and enhanced bioavailability, has been shown in drugs encapsulated in lipid nanoparticles. Their applications in wound care show potential for overcoming impediments, such as the inadequate bioavailability of active agents with low solubility. Future research in nanosized-lipid-based drug delivery systems will allow the achievement of increased bioavailability and better control of drug release, providing the clinician with more effective therapies for wound care.

Chitosan and phospholipid assisted topical fusidic acid drug delivery in burn wound: Strategies to conquer pharmaceutical and clinical challenges, opportunities and future panorama

Burn is the immense public health issue globally. Low and middle income countries face extensive deaths owing to burn injuries. Availability of conventional therapies for burns has always been painful for patients as well as expensive for our health system. Pharmaceutical experts are still searching reliable, cheap, safe and effective treatment options for burn injuries. Fusidic acid is an antibiotic of choice for the management of burns. However, fusidic acid is encountering several pharmaceutical and clinical challenges like poor skin permeability and growing drug resistance against burn wound microbes like Methicillin resistant Staphylococcus aureus (MRSA). Therefore, an effort has been made to present a concise review about molecular pathway followed by fusidic acid in the treatment of burn wound infection in addition to associated pros and cons. Furthermore, we have also summarized chitosan and phospholipid based topical dermal delivery systems customized by our team for the delivery of fusidic acid in burn wound infections on case-to-case basis. However, every coin has two sides. We recommend the integration of in-silico docking techniques with natural biomacromolecules while designing stable, patient friendly and cost effective topical drug delivery systems of fusidic acid for the management of burn wound infection as future opportunities.

Nanocrystals of Fusidic Acid for Dual Enhancement of Dermal Delivery and Antibacterial Activity: In Vitro, Ex Vivo and In Vivo Evaluation

With the alarming rise in incidence of antibiotic-resistant bacteria and the scarcity of newly developed antibiotics, it is imperative that we design more effective formulations for already marketed antimicrobial agents. Fusidic acid (FA), one of the most widely used antibiotics in the topical treatment of several skin and eye infections, suffers from poor water-solubility, sub-optimal therapeutic efficacy, and a significant rise in FA-resistant Staphylococcus aureus (FRSA). In this work, the physico-chemical characteristics of FA were modified by nanocrystallization and lyophilization to improve its therapeutic efficacy through the dermal route. FA-nanocrystals (NC) were prepared using a modified nanoprecipitation technique and the influence of several formulation/process variables on the prepared FA-NC characteristics were optimized using full factorial statistical design. The optimized FA-NC formulation was evaluated before and after lyophilization by several in-vitro, ex-vivo, and microbiological tests. Furthermore, the lyophilized FA-NC formulation was incorporated into a cream product and its topical antibacterial efficacy was assessed in vivo using a rat excision wound infection model. Surface morphology of optimized FA-NC showed spherical particles with a mean particle size of 115 nm, span value of 1.6 and zeta potential of −11.6 mV. Differential scanning calorimetry and powder X-ray diffractometry confirmed the crystallinity of FA following nanocrystallization and lyophilization. In-vitro results showed a 10-fold increase in the saturation solubility of FA-NC while ex-vivo skin permeation studies showed a 2-fold increase in FA dermal deposition from FA-NC compared to coarse FA. Microbiological studies revealed a 4-fofd decrease in the MIC against S. aureus and S. epidermidis from FA-NC cream compared to commercial Fucidin cream. In-vivo results showed that FA-NC cream improved FA distribution and enhanced bacterial exposure in the infected wound, resulting in increased therapeutic efficacy when compared to coarse FA marketed as Fucidin cream.

Evaluation of burn wound healing activity of novel fusidic acid loaded microemulsion based gel in male Wistar albino rats

The objective of the present research was to examine the possible usage of microemulsion based gel for fusidic acid (FA) dermal application as burn wound treatment. During the preparation of microemulsion, ethyl oleate as oil phase, tween 80 as a surfactant, ethanol as co-surfactant, water as aqueous phase were used. The prepared microemulsions were evaluated for clarity, pH, viscosity and FA content. Moreover, stability, sterility, antibacterial activity, in vitro release of the formulations were also evaluated. The results showed that the FA loaded microemulsion and microemulsion based gel formation and characteristics were related to many parameters of the components. The performed optimized microemulsion-based gel showed good stability over a period of 3 months. The antibacterial activity of microemulsion-based gel was found to be comparable with marketed cream. RAW 264.7 macrophages were used to determine cell viability (MTT assay) and nitric oxide production. MBG and FA-MBG significantly inhibit the production of the inflammatory mediator NO in LPS-stimulated RAW 264.7 cells in a concentration-dependent manner. The wound healing property was evaluated by histopathological examination and by measuring the wound contraction. The % of wound area in rats treated with FA (2%) loaded microemulsion based gel ranged from 69.30% to 41.39% in the period from 3 to 10 days. In conclusion, FA loaded microemulsion based gel could be offered as encouraging strategy as dermal systems for the burn wound treatment.

Topical Drug Delivery of Anti-infectives Employing Lipid-Based Nanocarriers: Dermatokinetics as an Important Tool

BACKGROUND

The therapeutic approaches for the management of topical infections have always been a difficult approach due to lack of efficacy of conventional topical formulations, high frequency of topical applications and non-patient compliance. The major challenge in the management of topical infections lies in antibiotic resistance which leads to severe complications and hospitalizations resulting in economic burden and high mortality rates.

METHODS

Topical delivery employing lipid-based carriers has been a promising strategy to overcome the challenges of poor skin permeation and retention along with large doses which need to be administered systemically. The use of lipid-based delivery systems is a promising strategy for the effective topical delivery of antibiotics and overcoming drug-resistant strains in the skin. The major systems include transfersomes, niosomes, ethosomes, solid lipid nanoparticles, nanostructured lipid carriers, microemulsion and nanoemulsion as the most promising drug delivery approaches to treat infectious disorders. The main advantages of these systems include lipid bilayer structure which mimics the cell membrane and can fuse with infectious microbes. The numerous advantages associated with nanocarriers like enhanced efficacy, improvement in bioavailability, controlled drug release and ability to target the desired infectious pathogen have made these carriers successful.

CONCLUSION

Despite the number of strides taken in the field of topical drug delivery in infectious diseases, it still requires extensive research efforts to have a better perspective of the factors that influence drug permeation along with the mechanism of action with regard to skin penetration and deposition. The final objective of the therapy is to provide a safe and effective therapeutic approach for the management of infectious diseases affecting topical sites leading to enhanced therapeutic efficacy and patient-compliance.

Nonwoven fabric supported, chitosan membrane anchored with curcumin/TiO2 complex: Scaffolds for MRSA infected wound skin reconstruction

Use of biomaterial scaffolds as drug carriers for infected wounds treatment is of wide scope. A series of curcumin/TiO₂ complex loaded chitosan scaffolds are fabricated for the same. Synthesized wound dressing material is screened for their morphology, water absorption capacity; in vitro drug release patterns, in vitro antibacterial studies against gram +ve and a gram -ve bacteria, cell viability for 3T3-L1 cell lines as well as in vivo MRSA infected wound healing capability. Formation of curcumin/TiO₂ complex was confirmed by X-ray diffraction studies, the anchoring pattern of them on the chitosan scaffold was analyzed by FESEM and EDS mapping. All membranes showed a better performance towards in vitro antibacterial and in vivo wound healing properties than the control ones in 14 days. The bacterial count on wound for a regular time period was measured and the scaffold with higher amount of curcumin in its complex is found to give the better performance, along with skin regeneration due to synergistic effect of curcumin and TiO₂.

Synergistic antibacterial effect of ultrasound microbubbles combined with chitosan-modified polymyxin B-loaded liposomes on biofilm-producing Acinetobacter baumannii

Purpose

Resistant strains of Acinetobacter baumannii (AB) that can form biofilms are resistant to polymyxin. Therefore, effective and safe polymyxin preparations against biofilm-producing AB are urgently needed. This study aims to prepare chitosan-modified polymyxin B-loaded liposomes (CLPs) and ultrasound microbubbles (USMBs) and then explore the synergistic antibacterial effects of USMBs combined with CLPs in vitro.

Methods

CLPs were prepared using a modified injection method, and microbubbles were prepared using a simple mechanical vibration method. Minimal biofilm inhibitory concentration (MBIC) of CLPs against resistant biofilm-producing AB was determined. Antibacterial activities of CLPs with or without USMBs were analyzed by crystal violet staining and resazurin assays to evaluate biofilm mass and viable counts, respectively. Then, the anti-biofilm effects of CLPs with or without USMBs on biofilm-producing AB were confirmed via scanning electron microscopy (SEM) analysis.

Results

We prepared CLPs that were 225.17±17.85 nm in size and carried positive charges of 12.64±1.44 mV. These CLPs, with higher encapsulation efficiency and drug loading, could exhibit a sustained release effect. We prepared microbubbles that were 2.391±0.052 µm in size and carried negative charges of −4.32±0.43 mV. The MBICs of the CLPs on the biofilm-producing AB was 8±2 µg/mL, while that of polymyxin B was 32±2 µg/mL. USMBs in combination with 2 µg/mL of polymyxin B could completely eliminate the biofilm-producing AB and achieve the maximum antimicrobial effects (P>0.05 vs sterile blank control). SEM imaging revealed some scattered bacteria without a biofilm structure in the USMB combined with the CLP group, confirming that this combination has the greatest anti-biofilm effects.

Conclusion

In this research, we successfully prepared USMBs and CLPs that have a more significant antibacterial effect on biofilm-forming AB than polymyxin B alone. Experiments in vitro indicate that the synergistic antibacterial effect of combining USMBs with CLPs containing as little as 2 µg/mL of polymyxin B is sufficient to almost eliminate drug-resistant biofilm-producing AB.