Preparation and optimization of lidocaine transferosomal gel containing permeation enhancers: a promising approach for enhancement of skin permeation

Nose-to-Brain Targeted Delivery of Donepezil Hydrochloride via Novel Hyaluronic Acid-Doped Nanotransfersomes for Alzheimer's Disease Mitigation

Alzheimer's disease is the most serious neurodegenerative disorder characterized by cognitive and memorial defects alongside deterioration in behavioral, thinking and social skills. Donepezil hydrochloride (DPZ) is one of the current two FDA-approved cholinesterase inhibitors used for the management of Alzheimer's disease. The current study aimed to formulate hyaluronic acid-coated transfersomes containing DPZ (DPZ-HA-TFS) for brain delivery through the intranasal pathway to surpass its oral-correlated GIT side effects. DPZ-HA-TFS were produced using a thin film hydration method and optimized with a 24 factorial design. The influence of formulation parameters on vesicle diameter, entrapment, cumulative release after 8 h, and ex vivo nasal diffusion after 24 h was studied. The optimal formulation was then evaluated for morphology, stability, histopathology and in vivo biodistribution studies. The optimized DPZ-HA-TFS formulation elicited an acceptable vesicle size (227.5 nm) with 75.83% entrapment efficiency, 37.94% cumulative release after 8 h, 547.49 µg/cm2 permeated through nasal mucosa after 24 h and adequate stability. Histopathological analysis revealed that the formulated DPZ-HA-TFS was nontoxic and tolerable for intranasal delivery. Intranasally administered DPZ-HA-TFS manifested significantly superior values for drug targeting index (5.08), drug targeting efficiency (508.25%) and direct nose-to-brain transport percentage (80.32%). DPZ-HA-TFS might be deemed as a promising intranasal nano-cargo for DPZ cerebral delivery to tackle Alzheimer's disease safely, steadily and in a non-invasive long-term pattern.

Unravelling the success of transferosomes against skin cancer: Journey so far and road ahead

Skin cancer remains one of the most prominent types of cancer. Melanoma and non-melanoma skin cancer are commonly found together, with melanoma being the more deadly type. Skin cancer can be effectively treated with chemotherapy, which mostly uses small molecular medicines, phytoceuticals, and biomacromolecules. Topical delivery of these therapeutics is a non-invasive way that might be useful in effectively managing skin cancer. Different skin barriers, however, presented a major obstacle to topical cargo administration. Transferosomes have demonstrated significant potential in topical delivery by improving cargo penetration through the circumvention of diverse skin barriers. Additionally, the transferosome-based gel can prolong the residence of drug on the skin, lowering the frequency of doses and their associated side effects. However, the choice of appropriate transferosome compositions, such as phospholipids and edge activators, and fabrication technique are crucial for achieving improved entrapment efficiency, penetration, and regulated particle size. The present review discusses skin cancer overview, current treatment strategies for skin cancer and their drawbacks. Topical drug delivery against skin cancer is also covered, along with the difficulties associated with it and the importance of transferosomes in avoiding these difficulties. Additionally, a summary of transferosome compositions and fabrication methods is provided. Furthermore, topical delivery of small molecular drugs, phytoceuticals, and biomacromolecules using transferosomes and transferosomes-based gel in treating skin cancer is discussed. Thus, transferosomes can be a significant option in the topical delivery of drugs to manage skin cancer efficiently.

Development of erlotinib-loaded nanotransferosomal gel for the topical treatment of ductal carcinoma in situ

Aims: This study was aimed to formulate erlotinib (ERL)-loaded transferosomal gel (ERL@TG) intended for topical application for the treatment of ductal carcinoma in situ. Materials & methods: The optimized process involved a thin-film hydration method to generate ERL-loaded transferosomes (ERL@TFS), which was incorporated into a carbopol gel matrix to generate ERL@TG. The optimized formulation was characterized in vitro followed by cytotoxicity evaluation on MCF-7 breast cancer cell lines and acute toxicity and skin irritation studies was performed in vivo. Results: In a comparative assessment against plain ERL, ERL@TG displayed enhanced efficacy against MCF-7 cell lines, reflected in considerably lower IC50 values with an enhanced safety profile. Conclusion: Optimized ERL@TG was identified as a promising avenue for addressing ductal carcinoma in situ breast cancer.

Asiatic acid-entrapped transfersomes for the treatment of hypertrophic scars: In vitro appraisal, bioactivity evaluation, and clinical study

Non-invasive treatment options for hypertrophic scars (HTS) are limited, and treating HTS remains challenging due to their unappealing appearance and associated social stigma. In this work, a novel transfersomal system named Asiatic acid-entrapped transfersomes (AATs) was prepared. AATs were evaluated for their skin permeability, anti-inflammatory activity, and other characteristic parameters to determine the most promising formulation. Asiatic acid-entrapped transfersomal gel (AATG), which was obtained by incorporating the lead AATs in a gel base, underwent testing in an 8-week, double-blind, placebo-controlled, split-skin clinical study. The net skin elasticity (R5), melanin index (MI), and skin surface hydration were analyzed employing Cutometer®, Mexameter®, and Corneometer®, respectively, in order to evaluate the effectiveness of the developed AATG. AATs exhibited vesicular sizes and zeta potential values within the range of (27.15 ± 0.95 to 63.54 ± 2.51 nm) and (-0.010 to -0.129 mV), respectively. TW80AAT gave the highest %EE (90.84 ± 2.99%), deformability index (101.70 ± 11.59 mgs-1), permeation flux at 8 h (0.146 ± 0.005 mg/cm2/h), and anti-inflammatory activity (71.65 ± 1.83%). The clinical study results of AATG indicated no adverse skin reactions. Furthermore, product efficacy tests demonstrated a significant reduction in MI and an increase in net skin elasticity at 2, 4, and 8 weeks. These pilot study outcomes support the effectiveness of the AATG.

Transfersome, an ultra-deformable lipid-based drug nanocarrier: an updated review with therapeutic applications

The application of nanotechnology with integration of chemical sciences is increasing continuously in the management of diseases. The drug's physicochemical and pharmacological characteristics are enhanced by application of nanotechnological principles. Several nanotechnology-based formulations are being investigated to improve patient compliance. One such novel nanocarrier system is transfersome (TFS) and is composed of natural biocompatible phospholipids and edge activators. Morphologically, TFS are similar to liposomes but functionally, these are ultra-deformable vesicles which can travel through pores smaller than their size. Because of their amphipathic nature, TFS have the potential to deliver the drugs through sensitive biological membranes, especially the blood-brain barrier, skin layers, and nasal epithelium. Different molecular weight drugs can be transferred inside the cell by encapsulation into the TFS. Knowing the tremendous potentiality of TFS, the present work provides an in-depth and detailed account (pharmaceutical and preclinical characteristics) of TFS incorporating different categories of therapeutic moieties (anti-diabetic, anti-inflammatory, anti-cancer, anti-viral, anti-fungal, anti-oxidant, cardiovascular drugs, CNS acting drugs, vaccine delivery, and miscellaneous applications). It also includes information about the methods of preparation employed, significance of excipients used in the preparation, summary of clinical investigations performed, patent details, latest investigations, routes of administration, challenges, and future progresses related to TFS.

A simple, fast, and cost-effective smartphone-based digital imaging method for quantification of lidocaine hydrochloride in pharmaceutical formulations

OBJECTIVE

A simple, highly specific, accurate and fast method by smartphone-based digital imaging was developed for estimating lidocaine hydrochloride in pharmaceutical formulations.

MATERIAL AND METHODS

To obtain the images, a Galaxy A03 Core smartphone and an image acquisition device developed in the laboratory were used to control the incident factors in reproducibility of the measurements. The processing of the images was carried out with the Color Grab application. Finally, the absorbance values were calculated using the RGB intensity values of blank, standard, and sample solutions. The proposed method was compared with spectroscopic and chromatographic methods.

RESULTS

The reaction between copper and lidocaine hydrochloride was characterized, showing better results in an equimolar ratio and maintaining the pH of the solution above 11.5. The use of the device for the capture of digital images allowed to control those sensitive parameters for reproducibility so that the analytical measurements showed adequate precision and accuracy. Validation of the main parameters of the method showed compliance with acceptance criteria. The application of the method for the analysis of injectable samples achieved reliable results, which were statistically similar to other reference instrumental methods.

CONCLUSION

The proposed method presented figures of merit in relation to linearity, precision, selectivity, accuracy, and robustness; it was carried out by designing and manufacturing a device for capturing digital images on a smartphone, which were analyzed to obtain RGB intensity values. These data are finally used to calculate absorbance values of solutions. All these elements provide this work with innovative characteristics in the field of analysis for control of pharmaceutical formulations.

Acacetin-loaded microemulsion for transdermal delivery: preparation, optimization and evaluation

CONTEXT

Acacetin is reported as a potential drug candidate for the treatment of atrial fibrillation. However, clinical applications are limited by poor water solubility, limited ethanol solubility, and extremely low oral bioavailability.

OBJECTIVE

The present study prepared and evaluated acacetin-loaded microemulsion (ME) to achieve efficient pharmacokinetics together with no or minimal invasiveness for transdermal delivery.

MATERIALS AND METHODS

The formulation of ME was determined by the water titration method based on solubility results. The optimized formulation was achieved by the simplex lattice experiment design. The optimized ME formulations FA, FB and FC (FA with 10% and 50% DMSO as enhancers, respectively) were evaluated by ex vivo permeation with Franz diffusion cell and excised mice skin. In vivo pharmacokinetic studies were also performed at 8 mg/kg in rats within 6 h by transdermal administration.

RESULTS

The optimal ME (FA) was comprised of 12.2% caprylic acid decanoate monoditriglyceride (MCF-NF), 39.8% Smix (RH40: Trans = 2:1 w/w) and 48% water, respectively. Acacetin-loaded FA with particle size 36.0 ± 3.6 nm and drug solubility 803.7 ± 32.1 mg/g was prepared. FB had significantly higher cumulative amounts and higher AUC_0-∞ (196.6 ± 11.0 min × μg/mL, p < 0.05) than that FA alone (121.4 ± 33.1 min × μg/mL).

DISCUSSION AND CONCLUSIONS

The formulation of ME combined with the penetration enhancer can effectively improve the solubility and percutaneous absorption efficiency of acacetin, providing a new option for the non-invasive delivery of acacetin.

Microsponge-Based Gel Loaded with Immunosuppressant as a Simple and Valuable Strategy for Psoriasis Therapy: Determination of Pro-Inflammatory Response through Cytokine IL-2 mRNA Expression

Tacrolimus (TL) is a topical calcineurin inhibitor immunosuppressive drug widely used to manage various skin disorders. Herein, we report a TL-loaded microsphere gel formulation with severe atopic dermatitis effects that are required to manage skin disorders. The current study adopted a modified emulsion solvent evaporation technique to synthesize TL-loaded microspheres, which were further converted into gels for skin use. Characterization of the synthesized formulation was performed by differential dynamic light scattering, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray crystallography, Brunauer-Emmett-Teller (BET) analysis, differential scanning calorimetry, and drug release. A Franz diffusion cell was used to study the diffusion of TL for up to 8 h at pH 6.8 and 5.5. Evaluation of cell viability was determined by MTT assay and showed higher IC50 values compared to the plain drug. RNA extraction, real-time polymerase chain reaction (RT-PCR), and reverse transcription were also performed to determine the expression levels of the anti-inflammatory cytokine IL-2. Particle size determination was performed by a zeta sizer, and the TL microsphere size was 1745 ± 70 nm with a good polydispersity (0.337 ± 0.12). The drug entrapment efficiency was also very good at 60% ± 10, and the drug release was 93.9% ± 3.5 within 8 h. An in vitro diffusion study of the formulation also showed improved permeability at both pH values (4.5 and 5.5). The findings of the hemolytic tests demonstrated that TL-MG at concentrations of 50, 100, and 200 mg/mL did not produce any hemolysis. A dose-dependent pattern of cytotoxicity was found during the cell viability assay, with an IC50 value of 787.55 ± 12.78 µg/mL. There was a significant decrease in the IL-2 level in the TL-MG group compared to the other groups. TL-MG microspheres were nontoxic carriers for tacrolimus delivery, with greater loading capacity, a significant release profile, and enhanced cellular uptake with improved permeability.

Design and fabrication of Sesamol-loaded transfersomal gel for wound healing: physicochemical characterization and in-vivo evaluation

OBJECTIVE

In the present study, an attempt has been made to develop SL-loaded transfersomal gel for the effective treatment of delayed wound healing.

SIGNIFICANCE

The wound healing process consists of a complex series of biochemical events and changes in cellular activity that restore the integrity of the skin and the subcutaneous tissue. Sesamol (SL), which is a natural phenolic compound, is known for its antioxidant properties, anti-inflammatory properties, and wound-healing abilities.

METHODS

A thin-film hydration method was used to prepare SL-loaded transfersomes. Different formulations containing Tween-80 and Span-80 as edge activators were prepared and optimized. Various characteristics of vesicles were assessed, such as size, shape, loading efficiency, deformability, and in vitro skin penetration. The optimized formulation was then incorporated into 1% carbopol 940 gel. An in vivo wound healing potential of the selected formulation was assessed by an excision wound model.

RESULTS

The SL-loaded transfersomal gel displayed improved skin penetration and better skin deposition. Wound healing studies showed that the highest wound contraction was observed with SL-loaded transfersomes. Following 21 days of application of the transfersomal gel, a marked improvement in skin histological architecture was found.

CONCLUSION

The study findings suggest that transfersomal gel has great potential as a therapeutic option in wound healing.

Preparation and Optimization of Itraconazole Transferosomes-Loaded HPMC Hydrogel for Enhancing Its Antifungal Activity: 2^3 Full Factorial Design

Itraconazole (ITZ) is a triazole antifungal agent characterized by broad-spectrum activity against fungal infections. The main drawback of ITZ, when applied topically, is the low skin permeability due to the stratum corneum, the outermost layer of the skin, which represents the main barrier for drug penetration. Therefore, this study aimed to prepare itraconazole as transferosomes (ITZ-TFS) to overcome the barrier function of the skin. ITZ-TFSs were prepared by thin lipid film hydration technique using different surfactants, sodium lauryl sulfate (SLS) and sodium deoxycholate (SDC). The prepared ITZ-TFS were evaluated for entrapment efficiency (EE) %, particle size, polydispersity index (PDI), zeta potential, and in vitro drug release to obtain an optimized formula. The surface morphology of the optimized formula of ITZ-TFS was determined by transmission electron microscope (TEM). The optimized formulation was prepared in the form of gel using hydroxyl propyl methyl cellulose (HPMC) gel base. The prepared ITZ-TFS gel was evaluated for homogeneity, drug content, spreadability, pH, and in vitro antifungal activity in comparison with the free ITZ gel. The prepared ITZ-TFS formulations exhibited high EE% ranging from 89.02 ± 1.65% to 98.17 ± 1.28% with particle size ranging from 132.6 ± 2.15 nm to 384.1 ± 3.46. The PDI for all ITZ-TFSs was less than 0.5 and had a negative zeta potential. The TEM image for the optimized formulation (ITZ-TFS4) showed spherical vesicles with a smooth surface. The prepared gels had good spreadability, pH, and acceptable drug content. ITZ-TFS gel showed higher antifungal activity than free ITZ gel as determined by zone of inhibition. ITZ was successfully prepared in form of TFSs with higher antifungal activity than the free drug.

Review on Different Vesicular Drug Delivery Systems (VDDSs) and Their Applications

BACKGROUND

Colloidal dispersions, also known as vesicular drug delivery systems (VDDSs), are highly ordered assemblies composed of one or more concentric bilayers formed by the self-assembly of amphiphilic building blocks in the presence of water.

OBJECTIVE

VDDSs are important to target the entrapped drugs at specific sites inside the body, control the drug release, enhance the drug bioavailability, and reduce undesired side effects.

METHODS

There are different types of VDDSs suitable for the entrapment of both hydrophilic and lipophilic drugs. According to the patent composition, VDDSs are classified into lipid-based and nonlipid- based VDDSs.

RESULTS

There are different types of VDDSs which include liposomes, ethosomes, transferosomes, ufasomes, colloidosomes, cubosomes, niosomes, bilosomes, aquasomes, etc. Conclusion: This review article aims to address the different types of VDDSs, their advantages and disadvantages, and their therapeutic applications.

Lidosomes: Innovative Vesicular Systems Prepared from Lidocaine Surfadrug

Lidocaine is a local anaesthetic drug with an amphiphilic structure able to self-associate, under certain conditions, in molecular aggregates playing the role of both carrier and drug. The aim of this study was to determine the optimal conditions for obtaining vesicular carriers, called lidosomes. The new formulations were obtained using both lidocaine and lidocaine hydrochloride and different hydration medias (distilled water, acid, and basic aqueous solution). Lidosomes formulations were characterized in terms of size, ζ-potential, drug retained, stability formulation, and ex vivo permeation profile. Moreover, lidosomes were incorporated in two different gel structures: one based on carboxymethylcellulose and one based on pluronic F-127 to achieve suitable properties for a topical application. Results obtained showed that lidocaine showed a better performance to aggregate in vesicular carriers in respect to hydrochloride form. Consequently, only formulations comprised of lidocaine were studied in terms of skin permeation performance and as carriers of another model drug, capsaicin, for a potential combined therapy. Lidocaine, when in form of vesicular aggregates, acted as percutaneous permeation enhancer showing better permeation profiles with respect to drug solutions. Moreover, lidosomes created a significant drug depot into the skin from which the drug was available for a prolonged time, a suitable feature for a successful local therapy.

Design of Liposomal Lidocaine/Cannabidiol Fixed Combinations for Local Neuropathic Pain Treatment

The administration of drug fixed combinations by nanocarriers is a new attractive approach since it can allow improvements in both the skin penetration of cargo compounds and their synergistic effects. The cutaneous administration of lidocaine (LD) and cannabidiol (CBD) combination can be useful for the local treatment of neuropathic pain. In fact, these drugs might exert a complementary effect on pain acting on sodium and calcium channels. In this study, the feasibility to deliver this combination in the deeper layers of the skin using deformable liposomes was studied. Based on a study of the drug affinity for lipid components performed by DSC, CBD was loaded in the lipid bilayer for limiting the leakage, while LD was loaded in the inner core by a pH gradient method (G-liposomes) or after previous encapsulation in micelle (DiMiL). The effect of the presence of Tween 80 in the liposome membrane was also evaluated. DiMiL increased both the skin permeation and the retention in the dermis of CBD and LD with respect to G-liposomes (R_24dermis: 11.52 ± 2.4 against 4.51 ± 0.8 µg/cm² for CBD; 19.6 ± 2.9 against 3.2 ± 0.1 µg/cm² for LD). Moreover, both DiMiL and G-liposomes were more efficient than control formulations carrying free drugs in improving drug skin permeation. Interestingly, in the presence of a drug exerting a fluidizing effect such as CBD, the removal of Tween 80 from the composition led to an improved control of drug release and a higher extent of drug retention in the dermis layer.

Preparation, Characterization and Permeation Study of Topical Gel Loaded with Transfersomes Containing Asiatic Acid

The objective of this study is to investigate the in vitro permeation of asiatic acid (AA) in the form of a topical gel after entrapment in transfersomes by Franz diffusion cells. Transfersomes composed of soybean lecithin and three different edge activators including Tween 80 (TW80), Span 80 (SP80) and sodium deoxycholate (SDC) at the ratio of 50:50, 90:10 and 90:10, respectively, together with 0.3% w/w of AA, were prepared by a high-pressure homogenization technique and further incorporated in gels (TW80AATG, SP80AATG and SDCAATG). All transfersomal gels were characterized for their AA contents, dynamic viscosity, pH and homogeneity. Results revealed that the AA content, dynamic viscosity and pH of the prepared transfersomal gels ranged from 0.272 ± 0.006 to 0.280 ± 0.005% w/w, 812.21 ± 20.22 to 1222.76 ± 131.99 Pa.s and 5.94 ± 0.03 to 7.53 ± 0.03, respectively. TW80AATG gave the highest percentage of AA penetration and flux into the Strat-M^® membrane at 8 h (8.53 ± 1.42% and 0.024 ± 0.008 mg/cm²/h, respectively) compared to SP80AATG (8.00 ± 1.70% and 0.019 ± 0.010 mg/cm²/h, respectively), SDCAATG (4.80 ± 0.50% and 0.014 ± 0.004 mg/cm²/h, respectively), non-transfersomal gels (0.73 ± 0.44 to 3.13 ± 0.46% and 0.002 ± 0.001 to 0.010 ± 0.002 mg/cm²/h, respectively) and hydroethanolic AA solution in gel (1.18 ± 0.76% and 0.004 ± 0.003 mg/cm²/h, respectively). These findings indicate that the TW80AATG might serve as a lead formulation for further development toward scar prevention and many types of skin disorders.

PAMAM Dendrimers: A Review of Methodologies Employed in Biopharmaceutical Classification

The oral route is the preferred way of drug administration for most drugs, whose treatment success is directly related to the compound intestinal absorption. This absorption process, in its turn, is influenced by several factors impacting the drug bioavailability, which is extremely dependent on the maximum solubility and permeability. However, optimizing these last two factors, without chemical structural modification, is challenging. Although poly(amidoamine) dendrimers (PAMAM) are an innovative and promising strategy as drug delivery compounds, there are few studies that determine the permeability and solubility of PAMAM-drugs derivatives. Considering this scenario, this paper aimed to carry out a literature review of the last five years concerning biopharmaceutical characterizations of dendrimer delivery systems. In vitro methodologies, such as the Parallel artificial membrane permeability assay (PAMPA) (non-cellular based model) and Caco-2 cells (cellular based model), used for the permeability evaluation in the early stages of drug discovery proved to be the most promising methodologies. As a result, we discussed, for instance, that through the usage of PAMPA it was possible to evaluate the higher capacity for transdermal delivery of DNA of TAT-conjugated PAMAM, when in comparison with unmodified PAMAM dendrimer with a P<0.05. We also presented the importance of choosing the best methods of biopharmaceutical characterization, which will be essential to guarantee the efficacy and safety of the drug candidate.

Preparation and Optimization of an Ultraflexible Liposomal Gel for Lidocaine Transdermal Delivery

The pain caused by lidocaine injections into the face prior to facial plastic surgeries intended to remove growths or tumorous lesions has been reported by many patients to be the worst part of these procedures. However, the lidocaine gels and creams currently on the market do not deliver an equal or better local anesthetic effect to replace these injections. To develop an alternative to the painful local anesthetic injection, we prepared ultraflexible liposomes using soy phosphatidylcholine, lidocaine, and different amounts of sodium cholate, a surfactant. The prepared ultraflexible liposomes (UFLs) were examined for particle size, zeta potential, cytotoxicity, and in vitro release. By using a carbomer as a gelling agent, the prepared UFL lidocaine gels were evaluated for their penetration ability in a Franz diffusion cell, using Strat-M membranes. The formulation achieving the highest amount of penetrated lidocaine was chosen for further pH, viscosity, and stability tests. The local anesthetic efficacy of the formulation was investigated by an in vivo tail-flick test in rats. Our findings suggested that this topical gel formulated with ultraflexible liposomal lidocaine has enhanced skin permeation ability, as well as an improved local analgesic effect from the lidocaine.

A Narrative Review of the Potential Roles of Lipid-Based Vesicles (Vesiculosomes) in Burn Management

Burn injuries can have a lasting effect on people’s quality of life, as they negatively impact their physical and mental health. Then, they are likely to suffer psychological problems as a result. A serious problem is that deep burns are more challenging to treat due to their slow healing rate and susceptibility to microbial infection. Conventional topical medications used for burn treatment are sometimes ineffective because they cannot optimize their ability of transcutaneous absorption at the targeted site and accelerate healing. However, nanotechnology offers excellent prospects for developing current medical wound therapies and is capable of addressing issues such as low drug stability, water solubility, permeability, and bioavailability. The current review focuses on lipid-based vesicles (vesiculosomes) as an example of advanced delivery systems, showing their potential clinical applications in burn wound management. Vesiculosomes may help overcome impediments including the low bioavailability of active agents, offering the controlled release of drugs, increased drug stability, fewer side effects, and reduced dosing frequency, which will ultimately improve therapeutic efficacy and patient compliance. We discuss the application of various types of vesiculosomes such as liposomes, niosomes, ethosomes, cubosomes, transfersomes, and phytosomes in burn healing therapy, as these demonstrate superior skin penetration compared to conventional burn topical treatment. We also highlight their noteworthy uses in the formulation of natural products and discuss the current status as well as future perspectives of these carriers in burn management. Furthermore, the burn treatment options currently available in the market are also summarized.

Superiority of Microemulsion-based Hydrogel for Non-Steroidal Anti-Inflammatory Drug Transdermal Delivery: A Comparative Safety and Anti-nociceptive Efficacy Study

Non-steroidal anti-inflammatory drugs (NSAIDs) represent the foundation of pain management caused by inflammatory disorders. Nevertheless, their oral administration induces several side effects exemplified by gastric ulceration, thus, delivering NSAIDs via the skin has become an attractive alternative. Herein, microemulsion-based hydrogel (MBH), proliposomal, and cubosomal gels were fabricated, loaded with diclofenac, and physicochemically characterized. The sizes, charges, surface morphologies, and the state of diclofenac within the reconstituted gels were also addressed. The release pattern and ex-vivo permeation studies using Franz cells were performed via the rat abdominal skin. The formulations were assessed in-vivo on mice skin for their irritation effect and their anti-nociceptive efficacy through the tail-flick test. Biosafety study of the optimal gel was also pointed out. The gels and their dispersion forms displayed accepted physicochemical properties. Diclofenac released in a prolonged manner from the prepared gels. MBH revealed a significantly higher skin permeation and the foremost results regarding in-vivo assessment where no skin irritation or altered histopathological features were observed. MBH further induced a significant anti-nociceptive effect during the tail-flick test with a lower tendency to evoke systemic toxicity. Therefore, limonene-containing microemulsion hydrogel is a promising lipid-based vehicle to treat pain with superior safety and therapeutic efficacy.

D-optimal mixture design for optimization of topical dapsone niosomes: in vitro characterization and in vivo activity against Cutibacterium acnes

This study aimed to illustrate the use of D-optimal mixture design (DOMD) for optimization of an enhancer containing Dapsone niosomal formula for acne topical treatment. Mixture components (MixCs) studied were: Span 20, Cholesterol, and Cremophor RH. Different responses were measured. Optimized formula (OF) was selected to minimize particle size and maximize absolute zeta potential and entrapment efficiency. Optimized formula gel (OF-gel) was prepared and characterized. OF-gel in vivo skin penetration using confocal laser scanning microscopy and activity against Cutibacterium acnes in acne mouse model were studied. Based on DOMD results analysis, adequate models were derived. Piepel and contour plots were plotted accordingly to explain how alteration in MixCs L-pseudo values affected studied responses and regions for different responses’ values. The OF had suitable predicted responses which were in good correlation with the actually measured ones. The OF-gel showed suitable characterization and in vivo skin penetration up to the dermis layer. In vivo acne mouse-model showed that OF-gel-treated group (OF-gel-T-gp) had significantly better recovery (healing) criteria than untreated (UT-gp) and Aknemycin^®-treated (A-T-gp) groups. This was evident in significantly higher reduction of inflammation percent observed in OF-gel-T-gp than both UT-gp and A-T-gp. Better healing in OF-gel-T-gp compared with other groups was also verified by histopathological examination. Moreover, OF-gel-T-gp and A-T-gp bacterial loads were non-significantly different from each other but significantly lower than UT-gp. Thus, DOMD was an adequate statistical tool for optimization of an appropriate enhancer containing Dapsone niosomal formula that proved to be promising for topical treatment of acne.

Transfersomes: a Revolutionary Nanosystem for Efficient Transdermal Drug Delivery

Transdermal delivery system has gained significance in drug delivery owing to its advantages over the conventional delivery systems. However, the barriers of stratum corneum along with skin irritation are its major limitations. Various physical and chemical techniques have been employed to alleviate these impediments. Among all these, transfersomes have shown potential for overcoming the associated limitations and successfully delivering therapeutic agents into systemic circulation. These amphipathic vesicles are composed of phospholipids and edge activators. Along with providing elasticity, edge activator also affects the vesicular size and entrapment efficiency of transfersomes. The mechanism behind the enhanced permeation of transfersomes through the skin involves their deformability and osmotic gradient across the application site. Permeation enhancers can further enhance their permeability. Biocompatibility; capacity for carrying hydrophilic, lipophilic as well as high molecular weight therapeutics; deformability; lesser toxicity; enhanced permeability; and scalability along with potential for surface modification, active targeting, and controlled release render them ideal designs for efficient drug delivery. The current review provides a brief account of the discovery, advantages, composition, synthesis, comparison with other cutaneous nano-drug delivery systems, applications, and recent developments in this area.

Lipid Nanoparticulate Drug Delivery Systems: Recent Advances in the Treatment of Skin Disorders

The multifunctional role of the human skin is well known. It acts as a sensory and immune organ that protects the human body from harmful environmental impacts such as chemical, mechanical, and physical threats, reduces UV radiation effects, prevents moisture loss, and helps thermoregulation. In this regard, skin disorders related to skin integrity require adequate treatment. Lipid nanoparticles (LN) are recognized as promising drug delivery systems (DDS) in treating skin disorders. Solid lipid nanoparticles (SLN) together with nanostructured lipid carriers (NLC) exhibit excellent tolerability as these are produced from physiological and biodegradable lipids. Moreover, LN applied to the skin can improve stability, drug targeting, occlusion, penetration enhancement, and increased skin hydration compared with other drug nanocarriers. Furthermore, the features of LN can be enhanced by inclusion in suitable bases such as creams, ointments, gels (i.e., hydrogel, emulgel, bigel), lotions, etc. This review focuses on recent developments in lipid nanoparticle systems and their application to treating skin diseases. We point out and consider the reasons for their creation, pay attention to their advantages and disadvantages, list the main production techniques for obtaining them, and examine the place assigned to them in solving the problems caused by skin disorders.

Formulation, Optimization and Evaluation of Luteolin-Loaded Topical Nanoparticulate Delivery System for the Skin Cancer

In the present study, luteolin (LT)-loaded nanosized vesicles (LT-NVs) were prepared by a solvent evaporation-hydration method using phospholipid and edge activator. The formulation was optimized using three factors at a three-level Box-Behnken design. The formulated LT-NVs were prepared using the three independent variables phospholipid (A), edge activator (B) and sonication time (C). The effect of used variables was assessed on the vesicle size (Y1) and encapsulation efficiency (Y2). The selection of optimum composition (LT-NVopt) was based on the point prediction method of the software. The prepared LT-NVopt showed the particle size of 189.92 ± 3.25 nm with an encapsulation efficiency of 92.43 ± 4.12% with PDI and zeta potential value of 0.32 and -21 mV, respectively. The formulation LT-NVopt was further converted into Carbopol 934 gel (1% w/v) to enhance skin retention. LT-NVoptG was further characterized for viscosity, spreadability, drug content, drug release, drug permeation and antioxidant, antimicrobial and cytotoxicity assessment. The evaluation result revealed optimum pH, viscosity, spreadability and good drug content. There was enhanced LT release (60.81 ± 2.87%), as well as LT permeation (128.21 ± 3.56 µg/cm2/h), which was found in comparison to the pure LT. The antioxidant and antimicrobial study results revealed significantly (p ˂ 0.05) better antioxidant potential and antimicrobial activity against the tested organisms. Finally, the samples were evaluated for cytotoxicity assessment using skin cancer cell line and results revealed a significant difference in the viability % at the tested concentration. LT-NVoptG showed a significantly lower IC50 value than the pure LT. From the study, it can be concluded that the prepared LT-NVoptG was found to be an alternative to the synthetic drug as well as conventional delivery systems.

Ultraflexible Liposome Nanocargo as a Dermal and Transdermal Drug Delivery System

A selected active pharmaceutical ingredient must be incorporated into a cargo carrier in a particular manner so that it achieves its goal. An amalgamation of active pharmaceutical ingredients (APIs) should be conducted in such a manner that it is simple, professional, and more beneficial. Lipids/polymers that are known to be used in nanocarriers for APIs can be transformed into a vesicular formulation, which offers elegant solutions to many problems. Phospholipids with other ingredients, such as ethanol and water, form suitable vesicular carriers for many drugs, overcoming many problems related to poor bioavailability, poor solubility, etc. Ultraflexible liposomes are novel carriers and new frontiers of drug delivery for transdermal systems. Auxiliary advances in vesicular carrier research have been made, enabling polymer-coated ethanolic liposomes to avoid detection by the body’s immune system—specifically, the cells of the reticuloendothelial system. Ultraflexible liposomes act as a cargo system and a nanotherapeutic approach for the transport of therapeutic drugs and bioactive agents. Various applications of liposome derivatives in different diseases are emphasized in this review.

Preparation and In Vivo Evaluation of a Lidocaine Self-Nanoemulsifying Ointment with Glycerol Monostearate for Local Delivery

Lidocaine, a commonly used local anesthetic, has recently been developed into a number of ointment products to treat hemorrhoids. This study examined its efficient delivery to the dermis through the pharmaceutical improvement of hemorrhoid treatment ointments. We attempted to increase the amount of skin deposition of lidocaine by forming a nanoemulsion through the self-nanoemulsifying effect that occurs when glycerol monostearate (GMS) is saturated with water. Using Raman mapping, the depth of penetration of lidocaine was visualized and confirmed, and the local anesthetic effect was evaluated via an in vivo tail-flick test. Evaluation of the physicochemical properties confirmed that lidocaine was amorphous and evenly dispersed in the ointment. The in vitro dissolution test confirmed that the nanoemulsifying effect of GMS accelerated the release of the drug from the ointment. At a specific concentration of GMS, lidocaine penetrated deeper into the dermis; the in vitro permeation test showed similar results. When compared with reference product A in the tail-flick test, the L5 and L6 compounds containing GMS had a significantly higher anesthetic effect. Altogether, the self-nanoemulsifying effect of GMS accelerated the release of lidocaine from the ointment. The compound with 5% GMS, the lowest concentration that saturated the dermis, was deemed most appropriate.

Improved Bioavailability of Ebastine through Development of Transfersomal Oral Films

The main objective of this research work was the development and evaluation of transfersomes integrated oral films for the bioavailability enhancement of Ebastine (EBT) to treat allergic rhinitis. The flexible transfersomes, consisting of drug (EBT), lipid (Phosphatidylcholine) and edge activator (EA) Polyoxyethylene sorbitan monooleate or Sorbitan monolaurate, were prepared with the conventional thin film hydration method. The developed transfersomes were further integrated into oral films using the solvent casting method. Transfersomes were evaluated for their size distribution, surface charge, entrapment efficiency (EE%) and relative deformability, whereas the formulated oral films were characterized for weight, thickness, pH, folding endurance, tensile strength, % of elongation, degree of crystallinity, water content, content uniformity, in vitro drug release and ex vivo permeation, as well as in vivo pharmacokinetic and pharmacodynamics profile. The mean hydrodynamic diameter of transfersomes was detected to be 75.87 ± 0.55 nm with an average PDI and zeta potential of 0.089 ± 0.01 and 33.5 ± 0.39 mV, respectively. The highest deformability of transfersomes of 18.52 mg/s was observed in the VS-3 formulation. The average entrapment efficiency of the transfersomes was about 95.15 ± 1.4%. Transfersomal oral films were found smooth with an average weight, thickness and tensile strength of 174.72 ± 2.3 mg, 0.313 ± 0.03 mm and 36.4 ± 1.1 MPa, respectively. The folding endurance, pH and elongation were found 132 ± 1, 6.8 ± 0.2 and 10.03 ± 0.4%, respectively. The ex vivo permeability of EBT from formulation ETF-5 was found to be approximately 2.86 folds higher than the pure drug and 1.81 folds higher than plain film (i.e., without loaded transfersomes). The relative oral bioavailability of ETF-5 was 2.95- and 1.7-fold higher than that of EBT-suspension and plain film, respectively. In addition, ETF-5 suppressed the wheal and flare completely within 24 h. Based on the physicochemical considerations, as well as in vitro and in vivo characterizations, it is concluded that the highly flexible transfersomal oral films (TOFs) effectively improved the bioavailability and antihistamine activity of EBT.

Identifying Underlying Issues Related to the Inactive Excipients of Transfersomes based Drug Delivery System

Transfersomes are bilayer vesicles composed of phospholipid and edge activators, which are mostly surfactant. Transfersomes based drug delivery system has gained a lot of interest of the pharmaceutical researchers for their ability to improve drug penetration and permeation through the skin. Transdermal drug delivery via transfersomes has the potential to overcome the challenge of low systemic availability. However, this complex vesicular system has different issues to consider for developing a successful transdermal delivery system. One of the major ingredients, phospholipid, has versatile sources and variable effect on the vesicle size and drug entrapment in transfersomes. The other one, termed as edge activators or surfactant, has some crucial consideration of skin damage and toxicity depending upon its type and concentration. A complex interaction between type and concentration of phospholipid and surfactant was observed, which affect the physicochemical properties of transfersomes. This review focuses on the practical factors related to these two major ingredients, such as phospholipid and surfactant. The origin, purity, desired concentration, the susceptibility of degradation, etc. are the important factors for selecting phospholipid. Regarding surfactants, the major aspects are type and desired concentration. A successful development of transfersomes based drug delivery system depends on the proper considerations of these factors and practical aspects.

Simultaneous Optimization of Oral and Transdermal Nanovesicles for Bioavailability Enhancement of Ivabradine Hydrochloride

PURPOSE

Ivabradine hydrochloride is selective pacemaker current (If) ion channel inhibitor used in case of chronic heart failure (CHF) with superior efficacy and lower side effects than most β-blockers. However, the drug suffers from low bioavailability (≈40%) due to extensive first-pass metabolism. Hence, this work aims to formulate nanovesicular platforms to enhance their bioavailability both orally and transdermally.

MATERIALS AND METHODS

A central composite face-centered design was employed to formulate the nanovesicles, both phosphatidylcholine: drug ratio and percentage of pluronic F68 were used as independent variables. The nine developed formulae were characterized in terms of vesicle size (nm), polydispersity index, zeta potential (mV), entrapment efficiency (%). Decreasing vesicle size, increasing negative value of the zeta potential, and increasing entrapment efficiency were the chosen constraints to optimize the engineered nanovesicles. The candidate formula was subjected to further investigation including lyophilization, loading into carbopol gel, in vitro release, imaging with a transmission electron microscope, histopathological examination, in vitro cytotoxicity study and in vivo pharmacokinetics.

RESULTS

The optimized nanovesicular formula was composed of lipid: drug ratio of 3.91:1 and 100% pluronic as a stabilizer. It has particle size, zeta potential and entrapment efficiency of 337.6 nm, -40.5 mV and 30.5, respectively. It was then lyophilized in the presence of 5% trehalose as a cryoprotectant, dispersed in 0.5% carbopol to develop the transdermal gel. The two different forms of the candidate formula (lyophilized and gel form) displayed sustained drug release in comparison to drug solution. The histopathological and cytotoxicity studies showed that the optimized formula was safe and highly biocompatible. The pharmacokinetics parameters measured declared a higher Cmax and half-life of both formulae in comparison to market product (Procoralan®) with a 2.54- and 1.85-folds increase in bioavailability, respectively.

CONCLUSION

Hence, the developed nanovesicles can be reported as the first nanoplatforms to be used for simultaneous ivabradine delivery by both oral and topical routes with enhanced oral and transdermal drug delivery. The developed nanoplatforms hence can be further used to formulate other drugs that suffer from low bioavailability due to extensive first-pass metabolism.

Recent Advances in Nanomaterials for Dermal and Transdermal Applications

The stratum corneum, the most superficial layer of the skin, protects the body against environmental hazards and presents a highly selective barrier for the passage of drugs and cosmetic products deeper into the skin and across the skin. Nanomaterials can effectively increase the permeation of active molecules across the stratum corneum and enable their penetration into deeper skin layers, often by interacting with the skin and creating the distinct sites with elevated local concentration, acting as reservoirs. The flux of the molecules from these reservoirs can be either limited to the underlying skin layers (for topical drug and cosmeceutical delivery) or extended across all the sublayers of the epidermis to the blood vessels of the dermis (for transdermal delivery). The type of the nanocarrier and the physicochemical nature of the active substance are among the factors that determine the final skin permeation pattern and the stability of the penetrant in the cutaneous environment. The most widely employed types of nanomaterials for dermal and transdermal applications include solid lipid nanoparticles, nanovesicular carriers, microemulsions, nanoemulsions, and polymeric nanoparticles. The recent advances in the area of nanomaterial-assisted dermal and transdermal delivery are highlighted in this review.

Liposomes and transferosomes: a breakthrough in topical and transdermal delivery

The topical and transdermal routes of drug administration are long known to the field of pharmaceutics. These routes have been explored for the delivery of a wide range of therapeutic agents over centuries. However, the anatomy of the skin and the physicochemical properties of molecules limit their transport via these routes. To overcome these challenges, a nano-phospholipid carrier called liposome was developed in the 1960s. Liposomal delivery of drugs was reported to be limited to the upper layers of skin. This led to the development of self-regulating and self-adaptable vesicles known as transfersomes. This review critically evaluates the barriers in delivery across the skin, recent advancements in liposomes, transfersomes and their impact in the pharmaceutical field.

Externally Triggered Novel Rapid-Release Sonosensitive Folate-Modified Liposomes for Gemcitabine: Development and Characteristics

PURPOSE

To develop an externally triggered rapid-release targeted system for treating ovarian cancer, gemcitabine (GMC) was entrapped into sonosensitive (SoS) folate (Fo)-modified liposomes (LPs).

METHODS

GMC-loaded LPs (GMC LPs), GMC-loaded Fo-targeted LPs (GMC-Fo LPs), and GMC-loaded Fo-targeted SoS LPs (GMC-SoS Fo LPs) were prepared utilizing a film-hydration technique and evaluated based on particle size, ζ-potential, and percentage entrapped drug. Cellular uptake of the fluorescent delivery systems in Fo-expressing ovarian cancer cells was quantified using flow cytometry. Finally, tumor-targeting ability, in vivo evaluation, and pharmacokinetic studies were performed.

RESULTS

GMC LPs, GMC-Fo LPs, and GMC-SoS Fo LPs were successfully prepared, with sizes of <120.3±2.4 nm, 39.7 mV ζ-potential, and 86.3%±1.84% entrapped drug. Cellular uptake of GMC-SoS Fo LPs improved 6.51-fold over GMC LPs (under ultrasonic irradiation - p<0.05). However, cellular uptake of GMC-Fo LPs improved just 1.24-fold over GMC LPs (p>0.05). Biodistribution study showed that of GMC concentration in tumors treated with GMC-SoS-Fo LPs (with ultrasound) improved 2.89-fold that of free GMC (p<0.05). In vivo, GMC-SoS Fo LPs showed the highest antiproliferative and antitumor action on ovarian cancer.

CONCLUSION

These findings showed that externally triggered rapid-release SoS Fo-modified LPs are a promising system for delivering rapid-release drugs into tumors.

QbD-Based Investigation of Dermal Semisolid in situ Film-Forming Systems for Local Anaesthesia

PURPOSE

The aim of our research work was to develop dermally applicable, lidocaine hydrochloride (LID-HCl)-containing semisolid in situ film-forming systems (FFSs) using the Quality by Design (QbD) approach to increase drug permeation into the skin.

METHODS

Silicones were used to improve the properties of formulations and to increase the permeation through the skin. The QbD approach was applied to ensure quality-based development. With initial risk assessment, the critical material attributes (CMAs) and the critical process parameters (CPPs) were identified to ensure the required critical quality attributes (CQAs).

RESULTS

During the initial risk assessment, four high-risk CQAs, namely in vitro drug release, in vitro drug permeation, drying properties, and mechanical properties, and three medium-risk CQAs, namely pH, viscosity, and film appearance were identified and investigated. Moreover, four high-risk CMAs were also considered during the formulation: permeation enhancing excipients, drying excipients, film-forming excipients, and emollients. During the experiments, LID-HCl influenced these critical parameters highly, thereby reducing the drying time. The formulation containing 25% silicone showed the best mechanical properties (49 mN skin adhesion, 20.3% film flexibility, 1.27 N film burst strength), which could predict better patient adherence. In addition, in vitro permeation studies showed that formulation containing 50% silicone has the fastest permeation rate. The flux of diffused API was 6.763 µg/cm2/h, which is much higher compared to the silicone-free formulation (1.5734 µg/cm2/h), and it can already be observed in the lower part of the dermis in 0.5 hour.

CONCLUSION

Our results show that LID-HCl has great influence on the critical parameters of FFSs. The silicone content can improve the applicability of formulations and has a favorable effect on the permeation rate of LID-HCl into the skin.

Oleic Acid Vesicles as a new Approach for Transdermal Delivery of Econazole Nitrate: Development, Characterization, and In-vivo Evaluation in Wistar rats

BACKGROUND

Cutaneous candidiasis is a deep-seated skin fungal infection that is most commonly observed in immunocompromised patients. This fungal infection is conventionally treated with various formulations like gels and creams which are having different side effects and least therapeutic efficacy. Hence, it becomes necessary to develop a novel carrier system for the treatment of this deep-seated skin fungal infection. Econazole nitrate is the most widely used antifungal for the treatment of cutaneous candidiasis, therefore, in present research work we developed and evaluated econazole nitrate loaded oleic acid vesicles for treatment of cutaneous candidiasis through transdermal route.

METHODS

Econazole nitrate loaded oleic acid vesicles were prepared by thin-film hydration and characterized for drug entrapment, vesicle size, zeta potential, polydispersity index (PDI), Fourier Transform-infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis. Furthermore, the oleic acid vesicular gel was evaluated for ex-vivo skin permeation/retention and in-vitro and in-vivo antifungal activity in Wistar rats.

RESULTS

Econazole nitrate loaded oleic acid vesicles showed high encapsulation of drug (74.76 ± 3.0%), acceptable size (373.4 ± 2.9 nm), and colloidal characteristics (PDI = 0.231 ± 0.078, zeta potential = -13.27 ± 0.80 mV). The oleic acid vesicular gel showed high skin permeation (Transdermal flux = 61.98 ± 2.45 μg/cm2/h), skin retention (35.90 ± 2.06%), in-vitro, and in-vivo antifungal activity compared to marketed cream (EcodermR) of econazole nitrate for a prolonged period of time (4 days).

CONCLUSION

Developed econazole nitrate loaded oleic acid vesicles could be used effectively in the treatment of cutaneous candidiasis with minimization of side effects of econazole nitrate with increased therapeutic efficacy.

Transfersomes: A Promising Nanoencapsulation Technique for Transdermal Drug Delivery

Transdermal delivery systems have gained much interest in recent years owing to their advantages compared to conventional oral and parenteral delivery systems. They are noninvasive and self-administered delivery systems that can improve patient compliance and provide a controlled release of the therapeutic agents. The greatest challenge of transdermal delivery systems is the barrier function of the skin's outermost layer. Molecules with molecular weights greater than 500 Da and ionized compounds generally do not pass through the skin. Therefore, only a limited number of drugs are capable of being administered by this route. Encapsulating the drugs in transfersomes are one of the potential approaches to overcome this problem. They have a bilayered structure that facilitates the encapsulation of lipophilic and hydrophilic, as well as amphiphilic, drug with higher permeation efficiencies compared to conventional liposomes. Transfersomes are elastic in nature, which can deform and squeeze themselves as an intact vesicle through narrow pores that are significantly smaller than its size. This review aims to describe the concept of transfersomes, the mechanism of action, different methods of preparation and characterization and factors affecting the properties of transfersomes, along with their recent applications in the transdermal administration of drugs.

Transfersomes: The Ultra-Deformable Carrier System for Non-Invasive Delivery of Drug

Vesicular systems have many advantages like prolonging the existence of the drug in the systemic circulation, minimizing the undesirable side-effects and helping the active moieties to reach their target sites using the carriers. However, the main drawback related to transdermal delivery is to cross stratum corneum, which can be overcome by the utilization of novel carrier systems e.g., transfersomes, which are ultra-deformable carrier systems composed of phospholipid (phosphatidylcholine) and edge activators (surfactants). Edge activators are responsible for the flexibility of the bilayer membranes of transfersomes. Different edge activators used in transfersomes include tween, span, bile salts (sodium cholate and sodium deoxycholate) and dipotassium glycyrrhizinate. These activators decrease the interfacial tension, thereby, increasing the deformability of the carrier system. Transfersomes can encapsulate both hydrophilic and hydrophobic drugs into a vesicular structure, which consists of one or more concentric bilayers. Due to the elastic nature of transfersomes, they can easily cross the natural physiological barriers i.e., skin and deliver the drug to its active site. The main benefit of using transfersomes as a carrier is the delivery of macromolecules through the skin by non-invasive route thereby increasing the patient's compliance. The transfersomal formulations can be used in the treatment of ocular diseases, alopecia, vulvovaginal candidiasis, osteoporosis, atopic dermatitis, tumor, leishmaniasis. It is also used in the delivery of growth hormones, anaesthesia, insulin, proteins, and herbal drugs. This review also focuses on the patents and clinical studies for various transfersomal products.

Nanomedicine Fight against Antibacterial Resistance: An Overview of the Recent Pharmaceutical Innovations

Based on the recent reports of World Health Organization, increased antibiotic resistance prevalence among bacteria represents the greatest challenge to human health. In addition, the poor solubility, stability, and side effects that lead to inefficiency of the current antibacterial therapy prompted the researchers to explore new innovative strategies to overcome such resilient microbes. Hence, novel antibiotic delivery systems are in high demand. Nanotechnology has attracted considerable interest due to their favored physicochemical properties, drug targeting efficiency, enhanced uptake, and biodistribution. The present review focuses on the recent applications of organic (liposomes, lipid-based nanoparticles, polymeric micelles, and polymeric nanoparticles), and inorganic (silver, silica, magnetic, zinc oxide (ZnO), cobalt, selenium, and cadmium) nanosystems in the domain of antibacterial delivery. We provide a concise description of the characteristics of each system that render it suitable as an antibacterial delivery agent. We also highlight the recent promising innovations used to overcome antibacterial resistance, including the use of lipid polymer nanoparticles, nonlamellar liquid crystalline nanoparticles, anti-microbial oligonucleotides, smart responsive materials, cationic peptides, and natural compounds. We further discuss the applications of antimicrobial photodynamic therapy, combination drug therapy, nano antibiotic strategy, and phage therapy, and their impact on evading antibacterial resistance. Finally, we report on the formulations that made their way towards clinical application.

Epidermal Delivery of Retinyl Palmitate Loaded Transfersomes: Penetration and Biodistribution Studies

The alteration of retinoids levels in the skin can cause different disorders in the maturation of epithelial skin cells. Topical administration of these lipophilic molecules is a challenge that can be addressed by encapsulation into drug delivery systems. In this study, retinyl palmitate transferosomes formulated in cream were developed and the increases in the penetration of the active ingredients as well as the biodistribution were evaluated in vitro and in vivo. Transfersomes demonstrated a significant increase in the administration of retinyl palmitate to the epidermis by quantification of the active ingredients in the different layers of the skin, as well as by fluorescence microscopy of biopsies of non-dermatomized pig-ear skin. These results suggest that transfersomes may be an efficient vehicle for the delivery of retinoids to inner layers of the skin, such as the epidermis.

Development and Evaluation of in-situ Nasal Gel Formulations of Nanosized Transferosomal Sumatriptan: Design, Optimization, in vitro and in vivo Evaluation

Background

Sumatriptan succinate (SUT) is a potent drug used for relieving or ending migraine and cluster headaches. SUT bioavailability is low (15%) when it is taken orally owing to its gastric breakdown and bloodstream before reaching the target arteries.

Aim

The aim of the study was to enhance SUT bioavailability through developing an intranasal transferosomal mucoadhesive gel.

Methods

SUT-loaded nanotransferosomes were prepared by thin film hydration method and characterized for various parameters such as vesicle diameter, percent entrapment efficiency (%EE), in vitro release and ex vivo permeation studies. The in-situ gels were prepared using various ratios of poloxamer 407, poloxamer 188, and carrageenan and characterized for gelation temperature, mucoadhesive strength, and rheological properties.

Results

The prepared transferosomes exhibited percent entrapment efficiencies (%EE) of 40.41±3.02 to 77.47±2.85%, mean diameters of 97.25 to 245.01 nm, sustained drug release over 6 hours, and acceptable ex vivo permeation findings. The optimum formulae were incorporated into poloxamer 407 and poloxamer 188-based thermosensitive in-situ gel using carrageenan as a mucoadhesive polymer. Pharmacokinetic evaluation showed that the prepared in-situ gel of SUT-loaded nano-transferosomes gave enhanced bioavailability, 4.09-fold, as compared to oral drug solution.

Conclusion

Based on enhancing the bioavailability and sustaining the drug release, it can be concluded that the in-situ gel of SUT-loaded nano-transferosomes were developed as a promising non-invasive drug delivery system for treating migraine.

Transferosomes as nanocarriers for drugs across the skin: Quality by design from lab to industrial scale

Transferosomes, also known as transfersomes, are ultradeformable vesicles for transdermal applications consisting of a lipid bilayer with phospholipids and an edge activator and an ethanol/aqueous core. Depending on the lipophilicity of the active substance, it can be encapsulated within the core or amongst the lipid bilayer. Compared to liposomes, transferosomes are able to reach intact deeper regions of the skin after topical administration delivering higher concentrations of active substances making them a successful drug delivery carrier for transdermal applications. Most transferosomes contain phosphatidylcholine (C18) as it is the most abundant lipid component of the cell membrane, and hence, it is highly tolerated for the skin, decreasing the risk of undesirable effects, such as hypersensitive reactions. The most common edge activators are surfactants such as sodium deoxycholate, Tween® 80 and Span® 80. Their chain length is optimal for intercalation within the C18 phospholipid bilayer. A wide variety of drugs has been successfully encapsulated within transferosomes such as phytocompounds like sinomenine or apigenin for rheumatoid arthritis and leukaemia respectively, small hydrophobic drugs but also macromolecules like insulin. The main factors to develop optimal transferosomal formulations (with high drug loading and nanometric size) are the optimal ratio between the main components as well as the critical process parameters for their manufacture. Application of quality by design (QbD), specifically design of experiments (DoE), is crucial to understand the interplay among all these factors not only during the preparation at lab scale but also in the scale-up process. Clinical trials of a licensed topical ketoprofen transferosomal gel have shown promising results in the alleviation of symptons in orthreothritis with non-severe skin and subcutaneous tissue disorders. However, the product was withdrawn from the market which probably was related to the higher cost of the medicine linked to the expensive manufacturing process required in the production of transferosomes compared to other conventional gel formulations. This example brings out the need for a careful formulation design to exploit the best properties of this drug delivery system as well as the development of manufacturing processes easily scalable at industrial level.

Nanogel loaded with surfactant based nanovesicles for enhanced ocular delivery of acetazolamide

Objective: Intraocular pressure has always been a great challenge for topical ophthalmic drugs. The study aimed to develop ocular surfactant based nanovesicles (NVs) carried in mucoadhesive nanogel providing efficient topical delivery of acetazolamide (ACZ). Methods: For the sake of optimizing formulation parameters, the effect of the type of edge activator and its ratio to sorbitan monostearate (Span 60) on the mean particle size, entrapment efficiency (%EE), and zeta potential (ZP) of produced NVs was investigated. Results: The selected formulation composed of Span 60:sodium deoxycholate with ratio 80:20 showed an average diameter of 202.90 nm, %EE of 90.2%, and ZP of -38.1 mV with a spherical and smooth surface. The ACZ loaded nanovesicles (ACZ-NVs) were embedded in different concentrations of Chitosan-sodium tripolyphosphate (CS-TPP) nanogels. The nanogel prepared using 1.5% CS showed the most promising viscosity, adhesion time, and rheological behavior (118,246 cP, 290 min, and thixotropic behavior, respectively). The in vitro release of ACZ showed a controlled release profile after incorporation in nanogels. The in vivo irritation test showed minimal irritation for the nanogel formulation compared to ACZ topical suspension. The effect of intraocular pressure lowering was significantly prolonged using ACZ-NV nanogels compared to ACZ oral tablets. Histopathological examination emphasized the healing power of CS on retinal atrophy. Conclusion: The research work indicated a promising potential for successful topical delivery of ACZ.