Development and evaluation of nanostructured lipid carrier-based hydrogel for topical delivery of 5-fluorouracil

Characterization Methods for Nanoparticle-Skin Interactions: An Overview

Research progresses have led to the development of different kinds of nanoplatforms to deliver drugs through different biological membranes. Particularly, nanocarriers represent a precious means to treat skin pathologies, due to their capability to solubilize lipophilic and hydrophilic drugs, to control their release, and to promote their permeation through the stratum corneum barrier. A crucial point in the development of nano-delivery systems relies on their characterization, as well as in the assessment of their interaction with tissues, in order to predict their fate under in vivo administration. The size of nanoparticles, their shape, and the type of matrix can influence their biodistribution inside the skin strata and their cellular uptake. In this respect, an overview of some characterization methods employed to investigate nanoparticles intended for topical administration is presented here, namely dynamic light scattering, zeta potential, scanning and transmission electron microscopy, X-ray diffraction, atomic force microscopy, Fourier transform infrared and Raman spectroscopy. In addition, the main fluorescence methods employed to detect the in vitro nanoparticles interaction with skin cell lines, such as fluorescence-activated cell sorting or confocal imaging, are described, considering different examples of applications. Finally, recent studies on the techniques employed to determine the nanoparticle presence in the skin by ex vivo and in vivo models are reported.

Anticancer and Chemosensitizing Effects of Menadione-Containing Peptide-Targeted Solid Lipid Nanoparticles

Vitamin K derivatives such as menadione (MD) have been recognized as promising redox-modulating and chemosensitizing agents for anticancer therapy, however, their cellular activities in peptide-targeted nanocarriers have not been elucidated to date. This study provides the guidelines for developing MD-loaded solid lipid nanoparticles (SLN) modified with extracellular matrix (ECM)-derived peptides. Relationships between RGD peptide concentration and changes in DLS characteristics as well as accumulation of SLN in cancer cells were revealed to adjust the peptide-lipid ratio. SLN system maintained adequate nanoparticle concentration and low dispersity after introduction of MD and MD/RGD, whereas formulated MD was protected from immediate conjugation with reduced glutathione (GSH). RGD-modified MD-containing SLN showed enhanced prooxidant, GSH-depleting and cytotoxic activities toward PC-3 prostate cancer cells attributed to improved cellular pharmacokinetics of the targeted formulation. Furthermore, this formulation effectively sensitized PC-3 cells and OVCAR-4 ovarian cancer cells to free doxorubicin and cisplatin so that cell growth was inhibited by MD-drug composition at nontoxic concentrations of the ingredients. These results provide an important background for further improving chemotherapeutic methods based on combination of conventional cytostatics with peptide-targeted SLN formulations of MD.

Nanostructured lipid carriers loaded into in situ gels for breast cancer local treatment

In this study, nanostructured lipid carriers (NLC) were developed and employed to obtain in situ thermosensitive formulations for the ductal administration and prolonged retention of drugs as a new strategy for breast cancer local treatment. NLC size was influenced by the type and concentration of the oil phase, surfactants, and drug incorporation, ranging from 221.6 to 467.5 nm. The type of liquid lipid influenced paclitaxel and 5-fluorouracil cytotoxicity, with tributyrin-containing NLC reducing IC50 values by 2.0-7.0-fold compared to tricaprylin NLC in MCF-7, T-47D and MDA-MB-231 cells. In spheroids, the NLCs reduced IC50 compared to either drug solution (3.2-6.2-fold). Although a significant reduction (1.26 points, p < 0.001) on the health index of Galleria mellonella larvae was observed 5 days after NLC administration, survival was not significantly reduced. To produce thermosensitive gels, the NLCs were incorporated in a poloxamer (11 %, w/w) dispersion, which gained viscosity (2-fold) at 37 °C. After 24 h, ∼53 % of paclitaxel and 83 % of 5-fluorouracil were released from the NLC; incorporation in the poloxamer gel further prolonged release. Intraductal administration of NLC-loaded gel increased the permanence of hydrophilic (2.2-3.0-fold) and lipophilic (2.1-2.3-fold) fluorescent markers in the mammary tissue compared to the NLC (as dispersion) and the markers solutions. In conclusion, these results contribute to improving our understanding of nanocarrier design with increased cytotoxicity and prolonged retention for the intraductal route. Tributyrin incorporation increased the cytotoxicity of paclitaxel and 5-fluorouracil in monolayer and spheroids, while NLC incorporation in thermosensitive gels prolonged tissue retention of both hydrophilic and hydrophobic compounds.

Pentapeptide cRGDfK-Surface Engineered Nanostructured Lipid Carriers as an Efficient Tool for Targeted Delivery of Tyrosine Kinase Inhibitor for Battling Hepatocellular Carcinoma

Background

Antitumor research aims to efficiently target hepatocarcinoma cells (HCC) for drug delivery. Nanostructured lipid carriers (NLCs) are promising for active tumour targeting. Cell-penetrating peptides are feasible ligands for targeted cancer treatment.

Methods

In this study, we optimized gefitinib-loaded NLCs (GF-NLC) for HCC treatment. The NLCs contained cholesterol, oleic acid, Pluronic F-68, and Phospholipon 90G. The NLC surface was functionalized to enhance targeting with the cRGDfK-pentapeptide, which binds to the αvβ3 integrin receptor overexpressed on hepatocarcinoma cells.

Results

GF-NLC formulation was thoroughly characterized for various parameters using differential scanning calorimetry and X-ray diffraction analysis. In-vitro and in-vivo studies on the HepG2 cell line showed cRGDfK@GF-NLC's superiority over GF-NLC and free gefitinib. cRGDfK@GF-NLC exhibited significantly higher cytotoxicity, growth inhibition, and cellular internalization. Biodistribution studies demonstrated enhanced tumour site accumulation without organ toxicity. The findings highlight cRGDfK@GF-NLC as a highly efficient carrier for targeted drug delivery, surpassing non-functionalized NLCs. These functionalized NLCs offer promising prospects for improving hepatocarcinoma therapy outcomes by specifically targeting HCC cells.

Conclusion

Based on these findings, cRGDfK@GF-NLC holds immense potential as a highly efficient carrier for targeted drug delivery of anticancer agents, surpassing the capabilities of non-functionalized NLCs. This research opens up new avenues for effective treatment strategies in hepatocarcinoma.

Belinostat loaded lipid-polymer hybrid nanoparticulate delivery system for breast cancer: improved pharmacokinetics and biodistribution in a tumor model

Despite various treatment modalities for breast cancer, it still persists as one of the most diagnosed types of cancer in females. The recent investigations in the epigenetics of breast cancer reveal several aberrations in the expression levels of various HDAC enzymes. Henceforth, the present work entails the formulation and characterization of a lipid polymer-based hybrid nanoparticulate (LPN) system for delivery of an epigenetic modulator drug, Belinostat, for its clinical application in breast cancer. The size of Belinostat nanoparticles prepared using a modified hot homogenization method was found to be 166.6 ± 19.95 nm with an encapsulation efficiency of 94.5 ± 5.1%. In vitro characterization for cytotoxicity, cellular uptake, and protein expression in two different breast cancer cells, 4T1 and MCF 7, revealed the superiority of the formulation in comparison with the free drug in MCF 7 cells. Subsequently, the behaviour of the formulation in in vivo settings of healthy and breast cancer xenograft bearing animals was analyzed using pharmacokinetic and biodistribution studies. The results revealed that the formulation demonstrated multi-fold improvement in the pharmacokinetic parameters in tumor bearing animals when compared with the free drug while no difference in pharmacokinetic behaviour was observed in healthy animals indicating the altered biodistribution and specificity of the formulation in breast tumor. This was confirmed by the biodistribution studies exhibiting 20-fold improved uptake and retention of the nanoparticulate formulation in tumor tissues of the animal model at the end of 4 h. Thus, the developed LPN system holds potential to act as a novel drug delivery system for Belinostat with several advantages over the free drug.

Multifunctional electrospun nanofibrous scaffold enriched with alendronate and hydroxyapatite for balancing osteogenic and osteoclast activity to promote bone regeneration

Electrospun composite nanofiber scaffolds are well known for their bone and tissue regeneration applications. This research is focused on the development of PVP and PVA nanofiber composite scaffolds enriched with hydroxyapatite (HA) nanoparticles and alendronate (ALN) using the electrospinning technique. The developed nanofiber scaffolds were investigated for their physicochemical as well as bone regeneration potential. The results obtained from particle size, zeta potential, SEM and EDX analysis of HA nanoparticles confirmed their successful fabrication. Further, SEM analysis verified nanofiber's diameters within 200-250 nm, while EDX analysis confirmed the successful incorporation of HA and ALN into the scaffolds. XRD and TGA analysis revealed the amorphous and thermally stable nature of the nanofiber composite scaffolds. Contact angle, FTIR analysis, Swelling and biodegradability studies revealed the hydrophilicity, chemical compatibility, suitable water uptake capacity and increased in-vitro degradation making it appropriate for tissue regeneration. The addition of HA into nanofiber scaffolds enhanced the physiochemical properties. Additionally, hemolysis cell viability, cell adhesion and proliferation by SEM as well as confocal microscopy and live/dead assay results demonstrated the non-toxic and biocompatibility behavior of nanofiber scaffolds. Alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) assays demonstrated osteoblast promotion and osteoclast inhibition, respectively. These findings suggest that developed HA and ALN-loaded PVP/PVA-ALN-HA nanofiber composite scaffolds hold significant promise for bone regeneration applications.

Dipeptide-1 modified nanostructured lipid carrier-based hydrogel with enhanced skin retention and topical efficacy of curcumin

Topical administration of curcumin (CUR), a natural polyphenol with potent anti-inflammation and analgesic activities, provides a potential approach for local skin diseases. However, the drug delivery efficiency is highly limited by skin barriers and poor bioavailability of CUR. Herein, we propose hydrogel containing CUR-encapsulated dipeptide-1-modified nanostructured lipid carriers (CUR-DP-NLCs gel) to enhance topical drug delivery, and improve the topical therapeutic effect. The prepared CUR-DP-NLCs were characterized and were suitably dispersed into the Pluronic F127 hydrogel for topical application. The optimized CUR-DP-NLCs had a particle size of 152.6 ± 3.47 nm, a zeta potential of -33.1 ± 1.46 mV, an entrapment efficiency of 99.83 ± 0.14%, and a spherical morphology. X-ray diffraction (XRD) studies confirmed that CUR was successfully entrapped by the NLCs in an amorphous form. CUR-DP-NLCs gel exhibited sustained release over 48 h and significantly increased the skin retention of CUR. In vitro skin retention of CUR with CUR-DP-NLCs gel was 2.14 and 2.85 times higher than that of unmodified NLCs gel and free CUR, respectively. Fluorescence microscopy imaging revealed the formed nanoparticles accumulated in the hair follicles with prolonged retention time to form a drug reservoir. The hematoxylin-eosin staining showed that CUR-DP-NLCs gel could change the microstructure of skin layers and disturb the skin barriers. After topical administration to mice, CUR-DP-NLCs gel showed better analgesic and anti-inflammatory activities with no potentially hazardous skin irritation. These results concluded that CUR-DP-NLCs gel is a promising strategy to increase topical drug delivery of CUR in the treatment of local skin diseases.

Assessment of anti-psoriatic activity of bakuchiol-loaded solid lipid nanoparticles-based gel: design, characterization, and mechanistic insight via NF-kB signaling pathway

The aim of the current study is to evaluate the anti-psoriatic potential of bakuchiol (Bak) loaded solid lipid nanoparticles (SLNs) via modulating inflammatory and oxidative pathways. Bak-loaded SLNs were prepared using hot homogenization method and characterized by various spectroscopic techniques. Bak-SLNs suspension was formulated into gel using Carbopol. Different in vivo assays were executed to explore the role of inflammatory markers and oxidative enzymes in psoriasis. DLS (dynamic light scattering) analysis showed suitable particle size, zeta potential, and polydispersity index (PDI) of developed formulation. TEM (transmission electron microscopy) reveal the spherical shape of Bak-SLNs particles. The release studies confirmed the sustained release of Bak-SLNs-based gel. UV-B-induced psoriatic Wistar rat model showed significant anti-psoriatic effect of Bak via regulating inflammatory markers (NF-kB, IL-6, IL-4, and IL-10) and levels of anti-oxidant enzymes, superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and glutathione-S-transferase (GST). Furthermore, RT-qPCR analysis confirms that Bak downregulates the expression of inflammatory markers, while histology and immunohistology results also confirm the anti-psoriatic effect of Bak. The study indicates that Bak-loaded SLNs-based gel significantly downregulates the level of cytokines and interleukins involve in NF-kB signaling cascade; hence, it can prove to be a novel therapeutic approach to cure psoriasis.

An Overview of Nanostructured Lipid Carriers and its Application in Drug Delivery through Different Routes

Nanostructured Lipid Carriers (NLC) are nano-sized colloidal drug delivery system that contains a lipid mixture consisting of both solid and liquid lipids in their core. This Lipid-Based Nanosystem is introduced as a biocompatible, non-toxic, and safe nano-drug delivery system as compared to polymeric or metallic nanoparticles. Due to its safety, stability, and high drug loading capacity compared to other lipid-based nanocarriers, NLC gained the attention of researchers to formulate safe and effective drug carriers. The ability to increase drug solubility and permeability while encapsulating the drug in a lipidic shell makes them an ideal carrier for drug delivery through difficult-to-achieve routes. Surface modification of NLC and the use of various additives result in drug targeting and increased residence time. With such qualities, NLCs can be used to treat a variety of diseases such as cancer, infections, neurodegenerative diseases, hypertension, diabetes, and pain management. This review focuses on the recent developments being made to deliver the drugs and genes through different routes via these nanocarriers. Here, we also discuss about historical background, structure, types of NLC and commonly employed techniques for manufacturing lipid-based nanocarriers.

c(RGDfK) anchored surface manipulated liposome for tumor-targeted Tyrosine Kinase Inhibitor (TKI) delivery to potentiate liver anticancer activity

Current anticancer drug research includes tumor-targeted administration as a critical component because it is the best strategy to boost efficacy and decrease toxicity. Low drug concentration in cancer cells, nonspecific distribution, rapid clearance, multiple drug resistance, severe side effects, and other factors contribute to the disappointing results of traditional chemotherapy. As an innovative technique of treatments for hepatocellular carcinoma (HCC) in recent years, nanocarrier-mediated targeted drug delivery systems can overcome the aforesaid limitations via enhanced permeability and retention effect (EPR) and active targeting. Epidermal growth factor receptor (EGFR) inhibitor Gefitinib (Gefi) has dramatic effects on hepatocellular carcinoma. Herein, we developed and assessed an α_vβ₃ integrin receptor targeted c(RGDfk) surface modified liposomes for better targeting selectivity and therapeutic efficacy of Gefi on HCC cells. The conventional and modified Gefi loaded liposomes, i.e., denoted as Gefi-L and Gefi-c(RGDfK)-L, respectively, were prepared through the ethanol injection method and optimized via Box Behnken design (BBD). The FTIR and ¹H-NMR spectroscopy verified that the c(RGDfK) pentapeptides had formed an amide bond with the liposome surface. In addition, the particle size, Polydispersity index, zeta potential, encapsulation efficiency, and in-vitro Gefi release of the Gefi-L and Gefi-c(RGDfK)-L were measured and analyzed. As indicated by the MTT assay on HepG2 cells, Gefi-c(RGDfK)-L displayed considerably higher cytotoxicity than Gefi-L or Gefi alone. Throughout the incubation period, HepG2 cells took up significantly more Gefi-c(RGDfK)-L than Gefi-L. According to the in vivo biodistribution analysis, Gefi-c(RGDfK)-L accumulated more strongly at the tumor site than Gefi-L and free Gefi. Furthermore, HCC-bearing rats treated with Gefi-c(RGDfK)-L showed a substantial drop in liver marker enzymes (alanine transaminase, alkaline phosphatase, aspartate transaminase, and total bilirubin levels) compared to the disease control group. Gefi-c(RGDfK)-L suppresses tumour growth more effectively than Gefi-L and free Gefi, according to an in vivo analysis of their anticancer activities. Thus, c(RGDfk)-surface modified liposomes, i.e., Gefi-c(RGDfK)-L may serve as an efficient carrier for the targeted delivery of anticancer drugs.

Multilayered nanofibrous scaffold of Polyvinyl alcohol/gelatin/poly (lactic-co-glycolic acid) enriched with hemostatic/antibacterial agents for rapid acute hemostatic wound healing

Electrospun nanofibers scaffolds show promising potential in wound healing applications. This work aims to fabricate nanofibrous wound dressing as a novel approach for a topical drug delivery system. Herein, the electrospinning technique is used to design and fabricate bioabsorbable nanofibrous scaffolds of Polyvinyl alcohol/gelatin/poly (lactic-co-glycolic acid) enriched with thrombin (TMB) as hemostatic agent and vancomycin (VCM) as anti-bacterial agent for a multifunctional platform to control excessive blood loss, inhibit bacterial growth and enhance wound healing. SEM, FTIR, XRD, in vitro drug release, antimicrobial studies, biofilm, cell viability assay, and in vivo study in a rat model were used to assess nanofiber's structural, mechanical, and biological aspects. SEM images confirms the diameter of nanofibers which falls within the range from 150 to 300 nm for all the batches. Excellent swelling index data makes it suitable to absorb wound exudates. In-vitro drug release data shows sustained release behavior of nanofiber. Nanofibers scaffolds showed biomimetic behavior and excellent biocompatibility. Moreover, scaffolds exhibited excellent antimicrobial and biofilm activity against Staphylococcus aureus. Nanofibrous scaffolds showed less bleeding time, rapid blood coagulation, and excellent wound closure in a rat model. ELISA study demonstrated the decreasing level of inflammatory markers, such as TNF-α, IL1β, and IL-6, making formulation promising for hemostatic wound healing applications. Finally, the study concludes that nanofibrous scaffolds loaded with TMB and VCM have promising potential as a dressing material for hemostatic wound healing applications.

Rapidly separable microneedle patch for the controlled and sustained release of 5-fluorouracil

5-Fluorouracil (5-FU) is frequently used in the treatment of tumors and swollen tissues. However, traditional administration methods can result in poor patient compliance and require to administrate frequently due to the short T_1/2 of 5-FU. Herein, the 5-FU@ZIF-8 loaded nanocapsules were prepared using multiple emulsion solvent evaporation methods to enable the controlled and sustained release of 5-FU. To decrease the drug release rate and enhance patient compliance, the obtained pure nanocapsules were added to the matrix to fabricate rapidly separable microneedles (SMNs). The entrapment efficiency (EE%) of 5-FU@ZIF-8 loaded nanocapsules was in the range of 41.55-46.29 %, and the particle size of ZIF-8, 5-FU@ZIF-8, and 5-FU@ZIF-8 loaded nanocapsules were 60 nm, 110 nm, and 250 nm respectively. According to the release study in vivo and in vitro, we concluded that 5-FU@ZIF-8 nanocapsules could achieve the sustained release of 5-FU and that the burst release of nanocapsules could be elegantly handled by incorporating nanocapsules into the SMNs. What's more, the use of SMNs could improve patient compliance due to the rapid separation of needles and backing of SMNs. The pharmacodynamics study also revealed that the formulation would be a better choice for the treatment of scars due to the advantages of painlessness, separation ability, and high delivery efficiency. In conclusion, the SMNs containing 5-FU@ZIF-8 loaded nanocapsules could serve as a potential strategy for some skin diseases therapy with controlled and sustained drug release behavior.

Solid lipid-based nanoparticulate system for sustained release and enhanced in-vitro cytotoxic effect of 5-fluorouracil on skin Melanoma and squamous cell carcinoma

The present study aimed to prepare solid lipid-based nanoparticles (SLNs) using Precirol® ATO 5 as solid lipid and Poloxamer 188 and Tween 80 as surfactant and co-surfactant respectively, and SLNs-derived gel for sustained delivery, enhanced in-vitro cytotoxicity, enhanced cellular uptake of 5-FU and enhanced permeation of 5-FU across the skin. The 5-FU-loaded SLNs were prepared by the hot melt encapsulation method and converted into SLN-derived gel using a gelling agent (Carbopol 940). The 5-FU-loaded SLNs had a particle size in the range of 76.82±1.48 to 327±4.46 nm, zeta potential between -11.3±2.11 and -28.4±2.40 mV, and entrapment efficiency (%) in range of 63.46±1.13 and 76.08±2.42. The FTIR analysis depicted that there was no chemical interaction between 5-FU and formulation components. Differential scanning calorimetric analysis showed thermal stability of 5-FU in the nanoparticles and powdered X-ray diffraction analysis revealed successful incorporation of 5-FU in nanoparticles. The in-vitro release study of 5-FU-loaded SLNs showed biphasic release behavior with initial burst release followed by sustained release over 48 hr. The 5-FU-loaded SLNs showed a greater cytotoxic effect on skin melanoma (B16F10 cells) and squamous cell carcinoma (A-431 cells) as compared to free 5-FU drug solution after 48 hr. Flow cytometry and fluorescence microscopy displayed enhanced quantitative and qualitative cellular uptake of SLNs. The SLNs formulation showed acceptable safety and biocompatible profile after an acute toxicity study in Wistar rats. Moreover, ex-vivo permeation studies depicted 2.13±0.076 folds enhanced flux of 5-FU-loaded SLN derived gel compared to 5-FU plain gel, and skin retention studies revealed target efficiency (%) 2.54±0.03 of 5-FU-loaded SLN derived gel compared to 5-FU plain gel.

Synthesis and characterization of a novel hydrogel based on carboxymethyl chitosan/sodium alginate with the ability to release simvastatin for chronic wound healing

Since wound dressing has been considered a promising strategy to improve wound healing, recent attention has been focused on the development of modern wound dressings based on synthetic and bioactive polymers. In this study, we prepared a multifunctional wound dressing based on carboxymethyl chitosan (CMC)/sodium alginate (Alg) hydrogel containing a nanostructured lipid carrier (NLC) in which simvastatin (SIM) has been encapsulated. This dressing aimed to act as a barrier against pathogens, eliminate excess exudates, and accelerate wound healing. Among various fabricated composites of dressing, the hydrogel composite with a CMC/sodium Alg ratio of 1:2 had an average pore size of about 98.44 ± 26.9 μm and showed 707 ± 31.9% swelling and a 2116 ± 79.2 g m-2per day water vapor transfer rate (WVTR), demonstrating appropriate properties for absorbing exudates and maintaining wound moisture. The NLC with optimum composition and properties had a spherical shape and uniform particle size distribution (74.46 ± 7.9 nm). The prepared nanocomposite hydrogel displayed excellent antibacterial activity againstEscherichia coliandStaphylococcus aureusas well as high biocompatibility on L929 mouse fibroblast cells. It can release the loaded SIM drug slowly and over a prolonged period of time. The highest drug release occurred (80%) within 14 d. The results showed that this novel nanocomposite could be a promising candidate as a wound dressing for treating various chronic wounds in skin tissues.

Influence of Vegetable Oils on In Vitro Performance of Lutein-Loaded Lipid Carriers for Skin Delivery: Nanostructured Lipid Carriers vs. Nanoemulsions

Nanostructured lipid carriers (NLC) were prepared from solid lipid (glyceryl monostearate, GMS) and vegetable oils, including palm oil (PO), rice bran oil (RBO) or virgin coconut oil (VCO), at different ratios (95:5, 90:10 and 80:20), while nanoemulsions (NE) were prepared with sole vegetable oils. After production, the particle size of the lutein-free NLC and NE was found to be between 100 and 150 nm and increased after loading with lutein. An increase in oil loading in NLC reduced the particle size and resulted in a less ordered lipid matrix and an increase in % entrapment efficiency. From the stability study, it was observed that the types of oils and oil content in the lipid matrix had an impact on the chemical stability of lutein. Regarding the release study, lutein-loaded NE showed higher release than lutein-loaded NLC. Both NLC and NE prepared from VCO exhibited higher release than those prepared from PO and RBO, respectively (p < 0.05). In contrast, among the formulations of NLC and NE, both lutein-loaded NLC and NE prepared from RBO showed the highest permeation through the human epidermis due to the skin enhancement effect of RBO. Based on all the results, the lipid nanocarriers composed of RBO could effectively enhance the chemical stability of lutein and promote drug penetration into the skin.

Nanostructured Lipid Carriers-Hydrogels System for Drug Delivery: Nanohybrid Technology Perspective

Advanced hybrid component development in nanotechnology provides superior functionality in the application of scientific knowledge for the drug delivery industry. The purpose of this paper is to review important nanohybrid perspectives in drug delivery between nanostructured lipid carriers (NLC) and hydrogel systems. The hybrid system may result in the enhancement of each component's synergistic properties in the mechanical strength of the hydrogel and concomitantly decrease aggregation of the NLC. The significant progress in nanostructured lipid carriers-hydrogels is reviewed here, with an emphasis on their preparation, potential applications, advantages, and underlying issues associated with these exciting materials.

Insightful exploring of advanced nanocarriers for the topical/transdermal treatment of skin diseases

Dermatological products constitute a big segment of the pharmaceutical market. From conventional products to more advanced ones, a wide variety of dosage forms have been developed till current date. A representative of the advanced delivery means is carrier-based systems, which can load large number of drugs for treatment of dermatological diseases, or simply for cosmeceutical purposes. To make them more favorable for topical delivery, further incorporation of these carriers in a topical vehicle, such as gels or creams is made. Therefore in this review article, an overview is compiled of the most commonly encountered novel carrier based topical delivery systems; namely lipid based (nanoemulsions, microemulsions, solid lipid nanoparticles [SLNs] and nanostructured lipid carriers [NLCs]), and vesicular carriers (non-deformable, such as liposomes, niosomes, emulsomes and cerosomes, and deformable, such as transfersomes, ethosomes, transethosomes, and penetration enhancer vesicles), with special emphasis on those loaded in a secondary gel vehicle. A special focus was made on the commonly encountered dermatological diseases, such as bacterial and fungal infections, psoriasis, dermatitis, eczema, vitiligo, oxidative damage, aging, alopecia, and skin cancer.

Determination of in vivo virtue of dermal targeted combinatorial lipid nanocolloidal based formulation of 5-fluorouracil and resveratrol against skin cancer

The current study has been designed to appraise the efficacy of developed combinatorial lipid-nanosystem-based gel (linogel) of 5-fluorouracil and resveratrol for skin cancer treatment. Initially, linogel was prepared and characterized for different parameters, namely pH, texture, drug content uniformity, occlusiveness, etc. Then in vivo efficacy studies (tumor number, area, and volume, histopathology, ultrastructural and immunohistochemical analysis) of linogel were determined over-developed skin tumors. Developed linogel possessed significantly (p < 0.05) better texture and occlusiveness than conventional gel formulation. Decreased tumor number, area, and volume showed significant results (p < 0.05) in favor of linogel. Histopathological and ultrastructural analysis confirmed superior efficacy of linogel in terms of marked improvement in the nucleus and subcellular structures in photomicrographs. The antioxidants and anti-inflammatory analysis findings showed a significantly (p < 0.05) potent effectiveness of linogel. The apoptotic and anti-proliferation activity of linogel was confirmed by analysis of caspase-3 and ki-67, which showed significant (p < 0.05) elevation in the level of cleaved caspase-3 and reduction in the level of ki-67 than untreated and conventional gel formulation treated tumors, indicating antitumor effect due to cancerous cell death. Thus, developed linogel fulfilled all the criteria of dermal application and exhibited efficacious therapeutic results, which could be a beneficial therapeutic approach against skin cancer.

Chitosan-Coated 5-Fluorouracil Incorporated Emulsions as Transdermal Drug Delivery Matrices

The purpose of the present study was to develop emulsions encapsulated by chitosan on the outer surface of a nano droplet containing 5-fluorouracil (5-FU) as a model drug. The emulsions were characterized in terms of size, pH and viscosity and were evaluated for their physicochemical properties such as drug release and skin permeation in vitro. The emulsions containing tween 80 (T80), sodium lauryl sulfate, span 20, and a combination of polyethylene glycol (PEG) and T20 exhibited a release of 88%, 86%, 90% and 92%, respectively. Chitosan-modified emulsions considerably controlled the release of 5-FU compared to a 5-FU solution (p < 0.05). All the formulations enabled transportation of 5-FU through a rat's skin. The combination (T80, PEG) formulation showed a good penetration profile. Different surfactants showed variable degrees of skin drug retention. The ATR-FTIR spectrograms revealed that the emulsions mainly affected the fluidization of lipids and proteins of the stratum corneum (SC) that lead to enhanced drug permeation and retention across the skin. The present study concludes that the emulsions containing a combination of surfactants (Tween) and a co-surfactant (PEG) exhibited the best penetration profile, prevented the premature release of drugs from the nano droplet, enhanced the permeation and the retention of the drug across the skin and had great potential for transdermal drug delivery. Therefore, chitosan-coated 5-FU emulsions represent an excellent possibility to deliver a model drug as a transdermal delivery system.

Docetaxel and Lidocaine Co-Loaded (NLC-in-Hydrogel) Hybrid System Designed for the Treatment of Melanoma

Melanoma is the most aggressive skin carcinoma and nanotechnology can bring new options for its pharmacological treatment. Nanostructured lipid carriers (NLC) are ideal drug-delivery carriers for hydrophobic drugs, such as the antineoplastic docetaxel (DTX), and hybrid (NLC-in-hydrogel) systems are suitable for topical application. This work describes a formulation of NLC_DTX in xanthan-chitosan hydrogel containing lidocaine (LDC) with anticancer and analgesia effects. The optimized nanoparticles encapsulated 96% DTX and rheological analysis revealed inherent viscoelastic properties of the hydrogel. In vitro assays over murine fibroblasts (NIH/3T3) and melanoma cells (B16-F10), human keratinocytes (HaCaT) and melanoma cells (SK-MEL-103) showed reduction of docetaxel cytotoxicity after encapsulation in NLC_DTX and HGel-NLC_DTX. Addition of LDC to the hybrid system (HGel-NLC_DTX-LDC) increased cell death in tumor and normal cells. In vivo tests on C57BL/6J mice with B16-F10-induced melanoma indicated that LDC, NLC_DTX, HGel-NLC_DTX-LDC and NLC_DTX + HGel-LDC significantly inhibited tumor growth while microPET/SPECT/CT data suggest better prognosis with the hybrid treatment. No adverse effects were observed in cell survival, weight/feed-consumption or serum biochemical markers (ALT, AST, creatinine, urea) of animals treated with NLC_DTX or the hybrid system. These results confirm the adjuvant antitumor effect of lidocaine and endorse HGel-NLC_DTX-LDC as a promising formulation for the topical treatment of melanoma.

Design and Optimization of New Enteric Nanoparticles of Ceftriaxone for Oral Delivery: In vitro and in vivo Assessments

PURPOSE

Development of new strategies for oral delivery of existing antibiotics administered exclusively through intravenous route is one of the global priorities of pharmaceutical research. The encapsulation of these active pharmaceutical agents within nanosized natural products offers several traits due to their tunable surface properties. Ceftriaxone (CTX) is an injectable, third-generation cephalosporin that suffers poor oral bioavailability.

METHODS

In the present study, ionic gelation of two biopolymers, namely chitosan (CH) and shellac (SH), was implemented to consolidate CTX, within elegant nanoparticles (NPs) for oral administration that would increase its bioavailability and sustainability. Quality by design approach (23 full factorial design) was adopted to optimize CTX-loaded nanoparticles. The optimized formula (F2) was characterized through transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy and differential scanning calorimetry (DSC). In vitro release behavior and stability study were also evaluated. Pharmacokinetic studies of enteric-coated hard gelatin capsules (HGCs) loaded with F2-NPs were finally assessed.

RESULTS

The optimized spherical F2-NPs had a mean particle size of 258 nm, zeta potential of about +30.1 and appreciable drug entrapment efficiency of 83%. The in vitro drug release profile of F2-NPs in pH 7.4 experienced biphasic configuration with an initial burst release for an hour, followed by a sustained release over 15 h with Higuchi model and non-Fickian diffusion mechanism (R2=0.9852). High stability upon storage at refrigerated and room temperature for 3 months and good flow properties (θ= 32.2 and HR= 1.13) of the optimized formula were also conferred. In vivo pharmacokinetic assessment in rabbits fruitfully displayed 92% absolute bioavailability of CTX.

CONCLUSION

The obtained results provide evidence for the potential combination of CH and SH in NPs preparation to enhance the oral bioavailability of CTX.

Eudragit S-100 Surface Engineered Nanostructured Lipid Carriers for Colon Targeting of 5-Fluorouracil: Optimization and In Vitro and In Vivo Characterization

5-Fluorouracil (5-FU) is the most preferred chemotherapeutic agent in the management of colon cancer but is associated with poor therapeutic efficacy and lack of site specificity. Hence, it was aimed to employ Eudragit S100 surface engineered 5-FU nanostructured lipid carriers for the spatial and temporal release of the drug for the treatment of colon cancer. Hot high-pressure homogenization (HPH) technique was employed in the preparation of 5-FU-NLCs. The optimization of 5-FU-NLCs was performed using a Quality by Design (QbD) approach. A 3² factorial design was employed wherein the relationship between independent variables [amount of oleic acid (X₁) and concentration of Tween®80 (X₂)] and dependent variables [particle size (Y₁) and % entrapment efficiency (Y₂)] was studied. Optimized 5-FU-NLCs were surface treated to obtain Eudragit S100-coated 5-FU-NLCs (EU-5-FU-NLCs). The evaluation parameters for 5-FU-NLCs and EU-5-FU-NLCs included surface morphology, particle size, PDI, and zeta potential. In vitro release from EU-5-FU-NLCs revealed a selective and controlled 5-FU release in the colonic region for 24 h. In vitro cytotoxicity (MTT assay) was performed against Caco-2 cancer cells, wherein EU-5-FU-NLCs exhibited a 2-fold greater cytotoxic potential in comparison to a 5-FU solution (5-FU-DS). Oral administration of EU-5-FU-NLCs in Albino Wistar rats depicted a higher C_max (2.54 folds) and AUC (11 folds) as well as prolonged T_max (16 folds) and MRT (4.32 folds) compared to 5-FU-DS confirming higher bioavailability along with the spatial and temporal release in the colonic region. Thus, a multifaceted strategy involving abridgement of nanotechnology along with surface engineering is introduced for effective chemotherapy of colon cancer via oral administration of 5-FU with uncompromised safety and higher efficacy.Graphical abstract.

Development and Characterization of n-Propyl Gallate Encapsulated Solid Lipid Nanoparticles-Loaded Hydrogel for Intranasal Delivery

The objective of the present study was to develop n-propyl gallate-loaded solid lipid nanoparticles (PG-SLNs) in a hydrogel (HG) formulation using Transcutol-P (TC-P) as a permeation enhancer. Modified solvent injection technique was applied to produce optimized PG-SLNs via the Quality by Design approach and central composite design. The in vitro mucoadhesion, scavenging activity, drug release, permeation studies of PG from PG-SLNs-loaded HG were evaluated under simulated nasal conditions. Compared with in vitro release behavior of PG from SLNs, the drug release from the PG-SLNs-loaded HG showed a lower burst effect and sustained release profile. The cumulative permeation of PG from PG-SLNs-loaded HG with TC-P was 600 μg/cm² within 60 min, which is 3–60-fold higher than PG-SLNs and native PG, respectively. Raman mapping showed that the distribution of PG-SLNs was more concentrated in HG having lower concentrations of hyaluronic acid. The scavenging assay demonstrated increased antioxidant activity at higher concentrations of HG. Due to enhanced stability and mucoadhesive properties, the developed HG-based SLNs can improve nasal absorption by increasing residence time on nasal mucosa. This study provides in vitro proof of the potential of combining the advantages of SLNs and HG for the intranasal delivery of antioxidants.

Pharmaceutical and Pharmacological Evaluation of the Effect of Nano-Formulated Spironolactone and Progesterone on Inflammation and Hormonal Levels for Managing Hirsutism Experimentally Induced in Rats

Hirsutism is a dermatological condition that refers to the excessive growth of hair in androgen-sensitive areas in women. Recently, the enhancement of the visible signs of a hairy female has taken special concern that affected the quality of life. The present study was developed to compare the follicular targeting effect of topical spironolactone (SP) or progesterone (PG)-loaded nanostructured lipid carrier (NLC) on the management of hirsutism. Four NLC formulations were prepared using cold homogenization techniques and pharmaceutically evaluated. SP-NLC and PG-NLC topical hydrogels were prepared to explore their pharmacological effect on letrozole induced polycystic ovarian syndrome (PCOS) in rats. Inflammatory mediators, antioxidant, and hormonal parameters were assayed. Additionally, histopathological examination was carried out to confirm the successful induction of PCOS. Results confirmed that all NLC formulations have a spherical shape with particle size ranged from 225.92 ± 0.41 to 447.80 ± 0.66 nm, entrapment efficiency > 75%, and zeta potential (- 31.4 to - 36.5 mV). F1 and F3 NLCs were considered as selected formulations for SP and PG, respectively. Female Wistar rats treated with F1 formulation for 3 weeks displayed better outcomes as manifested by the measured parameters as compared to the other tested groups. A significant reduction in hair follicle diameter and density was observed after topical application of SP or PG nano-gels. Finally, the outcomes pose a strong argument that the development of topically administered SP-NLC can be explored as a promising carrier over PG-NLC for more effectual improvement in the visible sign of hirsutism.

Subcutaneously Injectable Hyaluronic Acid Hydrogel for Sustained Release of Donepezil with Reduced Initial Burst Release: Effect of Hybridization of Microstructured Lipid Carriers and Albumin

The daily oral administration of acetylcholinesterase (AChE) inhibitors for Alzheimer’s disease features low patient compliance and can lead to low efficacy or high toxicity owing to irregular intake. Herein, we developed a subcutaneously injectable hyaluronic acid hydrogel (MLC/HSA hydrogel) hybridized with microstructured lipid carriers (MLCs) and human serum albumin (HSA) for the sustained release of donepezil (DNP) with reduced initial burst release. The lipid carrier was designed to have a microsized mean diameter (32.6 ± 12.8 µm) to be well-localized in the hydrogel. The hybridization of MLCs and HSA enhanced the structural integrity of the HA hydrogel, as demonstrated by the measurements of storage modulus (G′), loss modulus (G″), and viscosity. In the pharmacokinetic study, subcutaneous administration of MLC/HSA hydrogel in rats prolonged the release of DNP for up to seven days and reduced the initial plasma concentration, where the C_max value was 0.3-fold lower than that of the control hydrogel without a significant change in the AUC_last value. Histological analyses of the hydrogels supported their biocompatibility for subcutaneous injection. These results suggest that a new hybrid MLC/HSA hydrogel could be promising as a subcutaneously injectable controlled drug delivery system for the treatment of Alzheimer’s disease.

Combinatorial lipid-nanosystem for dermal delivery of 5-fluorouracil and resveratrol against skin cancer: Delineation of improved dermatokinetics and epidermal drug deposition enhancement analysis

In the present study, combinatorial nanostructured lipid carrier gel of 5-fluorouracil and resveratrol was formulated, optimized and characterized to enhance permeation in between epidermis and dermis layers of the skin to obtain a synergistic effect against skin cancer. After extensive trials, a newly modified emulsiosonication method was developed and additionally, for the first time, stability studies were done in the beginning to optimize formulation technique, which exhibited two major benefits simultaneously; first, it provided best-optimized technique for preparation of combinatorial lipid-nanosystem, and secondly, it also demonstrated a detailed report card of durability of formulations. In vitro release study showed a significantly improved, slow and prolonged release of drugs from the optimized lipid-nanosystem (***p < 0.05), which followed non-Fickian Higuchi kinetics. Besides, mechanism of skin permeation enhancement study, dermatokinetic assessment, and depth analysis of optimized formulation on skin exhibited improved permeation and well distribution of drugs up to the dermis layer of skin. Moreover, combinatorial linogel possessed significantly greater efficacy (**p < 0.01) on the A431 cell line, as compared to the conventional formulation. Thus, findings revealed that modified method of preparation for dual drug-loaded lipid-nanosystem lead to the production of a stable formulation that also improved the retention of both 5-fluorouracil and resveratrol in between the epidermis and dermis region of skin thereby helping in the management and treatment of skin cancer.

Formulation and evaluation of transdermal nanogel for delivery of artemether

Artemether (ART) is second to artesunate in being the most widely used derivatives of artemisinin in combination therapy of malaria. Nanostructured lipid carrier (NLC) formulations were prepared following our previous report using optimized ART concentration of 0.25 g dissolved in 5% w/v mixture of solid (Gelucire 43/01 and Phospholipon 85G) and liquid (Transcutol) lipids at 90 °C. An aqueous surfactant phase at 90 °C was added (dropwise) under magnetic stirring (1000 rpm) for 5 min. The pre-emulsion was speedily homogenized at 28,000 rpm for 15 min and further probe sonicated at 60% amplitude (15 min). Resultant sample was cooled at room temperature and frozen at - 80 °C prior to lyophilization. The freeze-dried sample was used for solid-state characterization as well as in the formulation of transdermal nanogels using three polymers (Carbopol 971P, Poloxamer 407, and Prosopis africana peel powder) to embed the ART-NLC, using ethanol as a penetration enhancer. Transdermal ART-nanogels were characterized accordingly (physical examination, pH, drug content, rheology, spreadability, stability, particle size and morphology, skin irritation, in vitro and ex vivo skin permeation, and analysis of permeation data), P < 0.05. Results indicated that ART nanogels showed good encapsulation, drug release, pH-dependent swelling, stability, and tolerability. Overall, ART nanogels prepared from Poloxamer 407 showed the most desirable drug permeation, pH, swellability, spreadability, viscosity, and transdermal antiplasmodial properties superior to PAPP-ANG > C971P-ANG. A two-patch/week concurrent application of the studied nanogels could offer 100% cure of malaria as a lower-dose (50 mg ART) patient-friendly regimen devoid of the drug's many side effects.

Curcumin loaded polycaprolactone-/polyvinyl alcohol-silk fibroin based electrospun nanofibrous mat for rapid healing of diabetic wound: An in-vitro and in-vivo studies

Electrospinning is emerging as a versatile technique nanofibers fabrication because due to their unique properties such as large surface area to volume ratio, porosity and maintaining moist wound environment, the nanofibers are able to deliver sustained drug release and oxygen to the wound for rapid healing of diabetic wound. The present work was aimed to prepare and evaluate silk fibroin-curcumin based nanofiber in combination with polycaprolactone (PCL) and polyvinyl alcohol (PVA) which helped to strengthen the wound healing properties of nanofiber. Silk fibroin is a naturally occurring polymer was selected one polymer for making nanofibrous mat due to its unique properties such as biodegradability, permeability, oxygen supply and maintain moisture content in the wound. SEM results showed diameters of fibers varied in the range between 200 and 350 nm and their tensile strength ranged from 12.41 to 16.80 MP. The nanofibers were causing sustained release of curcumin for many hours. The in-vivo wound healing studies in streptozotocin-induced diabetic mice showed rapid wound healing efficacy as compared to conventional formulations. Furthermore, the histopathological studies evidenced its ability to restore the normal skin structure and histological conditions of tissues. The silk fibroin-based nanofiber wound dressing, therefore appears to be an ideal preparation, in combination with curcumin, because it blends the anti-oxidant, anti-inflammatory properties of curcumin. Therefore, it was concluded that the silk fibroin-based nanofiber loaded with curcumin has great healing potential in diabetic wound.

Analytical tools and evaluation strategies for nanostructured lipid carrier-based topical delivery systems

INTRODUCTION

The inception of nanostructured lipid carriers (NLCs) proved to be a revolutionary step toward the treatment of dermatological disorders. To uncover its true potential, it is imperative that the system be characterized and evaluated comprehensively.

AREAS COVERED

The present review has been written to furnish an in-depth account of analytical tools and evaluation procedures under one roof. Besides discussing the challenges of topical delivery and benefits of NLCs, the paper elaborates on their physicochemical characterization. Further, in vitro evaluation of NLCs for dermatological benefits, followed by their evaluation in a hydrogel/cream base is covered. Lastly, disease-specific evaluation of NLC-based formulations is presented.

EXPERT OPINION

The research endeavors for NLCs have largely focused on the fabrication of NLCs for different bioactives. However, scientific efforts should be aimed toward the lesser explored realm of NLCs, i.e. exploitation of analytical techniques, such as Parelectric spectroscopy, Electron Spin Resonance, and Nuclear Magnetic Resonance spectroscopy. NLCs have been proven for their potential to foster the therapeutic modalities applicable to cutaneous disorders. More attention needs to be devoted to their evaluation for disease-specific parameters. The futuristic steps must involve clinical studies, to lay the path for their commercialization.

Nanomaterial Lipid-Based Carrier for Non-Invasive Capsaicin Delivery; Manufacturing Scale-Up and Human Irritation Assessment

Capsaicin is an active compound in chili peppers (Capsicum chinense) that has been approved for chronic pain treatment. The topical application of high-strength capsaicin has been proven to reduce pain; however, skin irritation is a major drawback. The aim of this study was to investigate an appropriate and scalable technique for preparing nanostructured lipid carriers (NLCs) containing 0.25% capsaicin from capsicum oleoresin (NLC_C) and to evaluate the irritation of human skin by chili-extract-loaded NLCs incorporated in a gel formulation (Gel NLC_C). High-shear homogenization with high intensity (10,000 rpm) was selected to create uniform nanoparticles with a size range from 106 to 156 nm. Both the NLC_C and Gel NLC_C formulations expressed greater physical and chemical stabilities than the free chili formulation. Release and porcine biopsy studies revealed the sustained drug release and significant permeation of the NLCs through the outer skin layer, distributing in the dermis better than the free compounds. Finally, the alleviation of irritation and the decrease in uncomfortable feelings following the application of the Gel NLC_C formulation were compared to the effects from a chili gel and a commercial product in thirty healthy volunteers. The chili-extract-loaded NLCs were shown to be applicable for the transdermal delivery of capsaicin whilst minimizing skin irritation, the major noncompliance cause of patients.

Quality by Design Approach for Preparation of Zolmitriptan/Chitosan Nanostructured Lipid Carrier Particles - Formulation and Pharmacodynamic Assessment

Purpose

Zolmitriptan (ZT) is a selective serotonin agonist that is used for the treatment of migraine. It belongs to BCS class III with high solubility and low permeability. Besides, the drug is subjected to pre-systemic metabolism. Accordingly, new Zolmitriptan/chitosan nanostructured lipid carriers (ZT/CT NLCs) coated with Tween 80 (stealthy layer) have been developed to overcome such demerits.

Methods

The NLCs were developed by combining ultrasonication and double emulsion (w/o/w) techniques. The lipids were Gelucire and Labrasol. Herein, the quality by design (2³ full factorial design) was scrupulously followed, where critical process parameters and critical quality attributes were predefined. The optimized formulation (F8) was fully characterized with respect to entrapment efficiency (%EE), percentage yield (% yield), particle size, size distribution (PDI), zeta potential (ZP), morphological appearance (TEM). In vitro release, stability study and pharmacodynamic evaluations were also assessed. The optimized freeze dried formula was dispensed in in situ gelling hard gelatin capsule encompassing pectin and guar gum for further in vitro and pharmacodynamic evaluations.

Results

The optimized spherical nanoparticles experienced high percentage EE and yield (78.14% and 60.19%, respectively), low particle size and PDI (343.87 nm and 0.209, respectively), as well as high negative ZP (−25.5 mV). It showed good physical stability at refrigerated conditions. The NLCs dispensed in in situ gelling hard gelatin capsule comprising pectin and guar gum experienced sustained release for 30 h and significantly maintained the pharmacological effect in mice up to 8 h (p < 0.001).

Conclusion

ZT, a BCS class III drug that suffers from poor permeability and pre-systemic metabolism, was successfully maneuvered as nanostructured lipid carrier particles (NLCs). The incorporation of the NLCs in in situ gelling hard gelatin capsules fulfilled a dual function in increasing permeability, as well as sustaining the pharmacodynamic effect. This result would open new vistas in improving the efficacy of other class III drugs.

Nanostructured Lipid Carriers as Potential Drug Delivery Systems for Skin Disorders

Background:

Skin diseases affect all the age groups of people and have an impact on patients’ physical, mental, and emotional status. Conventional topical preparation is limited with its efficacy due to low permeation, frequent application, and poor adherence to the therapy for prolong time.

Objective:

The objective of this review article is to address the emerging trends of nanotechnology derived lipidic carrier systems for an effective treatment for skin disorders.

Methodology:

Various research and review articles from reputed international journals were referred and compiled.

Results and Discussion:

opical drug delivery systems were found to be more effective than oral and parenteral drug delivery systems for treating skin diseases due to targeted localized applications with reduced side effects. Lipid-based nanoparticles have been found to have the potential in treating skin diseases due to the biocompatibility and the versatility of the lipids. Nanostructured lipid carriers (NLCs) have gained much attention in treating skin diseases due to improved stability of the drugs, enhanced skin permeation, retention, and better therapeutic efficacy. The review summarizes the NLCs characteristics and their application for topical delivery of various therapeutics in skin disorders. NLCs have shown great potential in effective drug delivery for the treatment of psoriasis, dermatitis, bacterial infections, and skin cancer. Its cosmetic application has opened a new area for skincare. Furthermore, safety and clinical status revealed its future commercial acceptability.

Conclusion:

NLCs have been found as effective lipid nanocarriers for the delivery of topical therapeutics.

Lipid Nanoparticles for Enhancing the Physicochemical Stability and Topical Skin Delivery of Orobol

Orobol is one of the major soy isoflavones, and has been reported to have various pharmacological activities, including an anti-skin-aging effect. However, since it has low solubility in water and physicochemical instability, the formulation of orobol for delivery into the dermal layer of the skin could be challenging. The objective of this study was to prepare lipid nanoparticles formulations of orobol to enhance its stability as well as its deposition into the skin. Formulations of orobol-loaded solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) were characterized in terms of their mean particle size, entrapment efficiency, and morphology. The nano-sized spherical NLCs formulations maintained the stability of orobol for up to 28 days. Moreover, the NLCs formulation significantly increased the in vitro deposition of orobol into both Strat-M membranes and human cadaver skin compared with the other formulations. Additionally, the NLCs formulation did not cause significant skin irritation in clinical study. These results demonstrate that a shea butter-based NLC formulation could be a promising and safe carrier system for improving the stability of orobol and enhancing its topical skin delivery.

Role of Rutin in 5-Fluorouracil-Induced Intestinal Mucositis: Prevention of Histological Damage and Reduction of Inflammation and Oxidative Stress

Intestinal mucositis, characterized by inflammatory and/or ulcerative processes in the gastrointestinal tract, occurs due to cellular and tissue damage following treatment with 5-fluorouracil (5-FU). Rutin (RUT), a natural flavonoid extracted from Dimorphandra gardneriana, exhibits antioxidant, anti-inflammatory, cytoprotective, and gastroprotective properties. However, the effect of RUT on inflammatory processes in the intestine, especially on mucositis promoted by antineoplastic agents, has not yet been reported. In this study, we investigated the role of RUT on 5-FU-induced experimental intestinal mucositis. Swiss mice were randomly divided into seven groups: Saline, 5-FU, RUT-50, RUT-100, RUT-200, Celecoxib (CLX), and CLX + RUT-200 groups. The mice were weighed daily. After treatment, the animals were euthanized and segments of the small intestine were collected to evaluate histopathological alterations (morphometric analysis); malondialdehyde (MDA), myeloperoxidase (MPO), and glutathione (GSH) concentrations; mast and goblet cell counts; and cyclooxygenase-2 (COX-2) activity, as well as to perform immunohistochemical analyses. RUT treatment (200 mg/kg) prevented 5-FU-induced histopathological changes and reduced oxidative stress by decreasing MDA concentrations and increasing GSH concentrations. RUT attenuated the inflammatory response by decreasing MPO activity, intestinal mastocytosis, and COX-2 expression. These results suggest that the COX-2 pathway is one of the underlying protective mechanisms of RUT against 5-FU-induced intestinal mucositis.

Omar M, A. Mahmoud H, A. Abou-Taleb H. Nanostructured Lipid Carriers to Mediate Brain Delivery of Temazepam: Design and In Vivo Study

The opposing effect of the blood–brain barrier against the delivery of most drugs warrants the need for an efficient brain targeted drug delivery system for the successful management of neurological disorders. Temazepam-loaded nanostructured lipid carriers (NLCs) have shown possibilities for enhancing bioavailability and brain targeting affinity after oral administration. This study aimed to investigate these properties for insomnia treatment. Temazepam-NLCs were prepared by the solvent injection method and optimized using a 4² full factorial design. The optimum formulation (NLC-1) consisted of; Compritol^® 888 ATO (75 mg), oleic acid (25 mg), and Poloxamer^® 407 (0.3 g), with an entrapment efficiency of 75.2 ± 0.1%. The average size, zeta potential, and polydispersity index were determined to be 306.6 ± 49.6 nm, −10.2 ± 0.3 mV, and 0.09 ± 0.10, respectively. Moreover, an in vitro release study showed that the optimized temazepam NLC-1 formulation had a sustained release profile. Scintigraphy images showed evident improvement in brain uptake for the oral ^99mTc-temazepam NLC-1 formulation versus the ^99mTc-temazepam suspension. Pharmacokinetic data revealed a significant increase in the relative bioavailability of ^99mTc-temazepam NLC-1 formulation (292.7%), compared to that of oral ^99mTc-temazepam suspension. Besides, the NLC formulation exhibited a distinct targeting affinity to rat brain. In conclusion, our results indicate that the developed temazepam NLC formulation can be considered as a potential nanocarrier for brain-mediated drug delivery in the out-patient management of insomnia.

Synthesis and Characterization of Nanostructured Lipid Nanocarriers for Enhanced Sun Protection Factor of Octyl p-methoxycinnamate

Sunlight is important to health, but higher exposure to radiation causes early aging of the skin and skin damage that can lead to skin cancers. This study aimed at producing a stable octyl p-methoxycinnamate (OMC)-loaded nanostructured lipid carrier (NLC) sunscreen, which can help in the photoprotective effect. NLC was produced by emulsification-sonication method and these systems were composed of myristyl myristate (MM), caprylic capric triglyceride (CCT), Tween® 80 (TW), and soybean phosphatidylcholine (SP) and characterized by dynamic light scattering (DLS), zeta potential (ZP) measurement, atomic force microscopy (AFM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and in vitro release studies. Pre-formulation studies were performed changing TW concentrations and no differences were found at concentrations of 1.0 and 2.0%. Two selected formulations were designed and showed an average size of 91.5-131.7, polydispersity index > 0.2, and a negative value of ZP. AFM presented a sphere-like morphology and SEM showed ability to form a thin film. DSC exhibited that the incorporation of OMC promoted reduction of enthalpy due to formation of a more amorphous structure. Drug release shows up to 55.74% and 30.57%, and this difference could be related to the presence of SP in this formulation that promoted a more amorphous structure; the release mechanism study indicated Fickian diffusion and relaxation. Sun protection factor (SPF) evaluation was performed using NLC and presented values around 40, considerably higher than those observed in the literature. The developed formulations provide a beneficial alternative to conventional sunscreen formulations.

Development of folic acid-loaded nanostructured lipid carriers for topical delivery: preparation, characterisation and ex vivo investigation

The present work is designed to achieve efficient localised skin delivery of folic acid (FA)-loaded nanostructured lipid carriers (NLCs) to infer efficient treatment of skin photoageing conditions induced via excessive exposure to ultraviolet (UV) radiation. FA NLCs were prepared by high-speed homogenisation followed by ultrasonication. The obtained NLCs revealed high encapsulation efficiencies (89.42-99.26%) with nanometric particle sizes (27.06-85.36 nm) of monodisperse distribution (PDI = 0.137-0.442), zeta potential values >|27| mV, pseudoplastic rheological behaviour, good spreadability (2.25-3.30 cm) and promoted occlusive properties throughout 48 h. Optimised NLC formulations appeared as sphere-shaped particles using transmission electron microscopy, showed improved photostability of FA and prolonged in vitro release profile best fitted to Higuchi diffusion model. Ex vivo permeation and deposition of FA, employing Wistar rat skins, depicted enhanced permeability and existence of FA in skin layers after 6 h. Based on the obtained results, FA-loaded NLC formulations demonstrate a promising modality for anti-photoageing therapy.

A comparative ex vivo permeation evaluation of a novel 5-Fluorocuracil nanoemulsion-gel by topically applied in the different excised rat, goat, and cow skin

AIM OF THE STUDY

5-Fluorouracil (5-FU) can't be given orally because of very low bioavailability and produces serious adverse effects. Therefore, the main objective of this research is to develop, evaluate, and comparative effects by different nanoformulations of topical application on chemoprevention of skin cancer in different types of skin.

MATERIAL AND METHODS

Castor oil (oil), Transcutol HP (surfactant), and Polyethylene glycol (PEG)-400 (co-surfactant) have taken on the basis of nonionic property and highest nanoemulsion (NE)-region. Aqueous micro titration method with ultra-sonication method (based on high energy) was used for the preparation of 5-FU-NE. Optimized-5-FU-NE was stable thermodynamically, and their characterizations was performed on the basis of globule size, zeta potential, refractive index, and viscosity. Optimized-NE has been converted into 5-FU-NE-Gel with the help of Carbopol® 934 and also performed their permeation studies in the different skins (cow, goat, and rat, ex vivo) using Logan transdermal diffusion cell (DHC-6T). Optimized-5-FU-NE and 5-FU-NE-Gel were evaluated cytotoxic studies (in vitro) on the melanoma cell lines.

RESULTS

The permeation of 5-FU from 5-FU-NE-Gel nanoformulation for rat skin model was 1.56 times higher than the 5-FU-NE and 12.51 times higher than the 5-FU-S for the cow and goat skin model. The values of steady state flux and permeability coefficient for 5-FU-NE-Gel of rat skin were higher i.e. 12.0244 ± 1.12 µgcm-2h-1 and 1.2024 ± 0.073 × 10-2 µg cm-2h-1, respectively. Optimized-5-FU-NE and 5-FU-NE-Gel nanoformulation were found to be physically stable. SK-MEL-5 cancer cells have showed the results based on cytotoxicity studies (in vitro) that 5-FU as Optimized-5-FU-NE-Gel is much more efficacious than 5-FU-NE followed by free 5-FU. Localization of 5-FU from 5-FU-NE-Gel was higher with higher permeation in rat skin.

CONCLUSION

5-FU-NE-Gel is found to be for the better to treatment of cutaneous malignancies. It can be developed 5-FU-NE-Gel could be a promising vehicle for the skin cancer chemoprevention.

Nanostructured Lipid Carriers: A Groundbreaking Approach for Transdermal Drug Delivery

Nanostructured lipid carriers (NLCs) are novel pharmaceutical formulations which are composed of physiological and biocompatible lipids, surfactants and co-surfactants. Over time, as a second generation lipid nanocarrier NLC has emerged as an alternative to first generation nanoparticles. This review article highlights the structure, composition, various formulation methodologies, and characterization of NLCs which are prerequisites in formulating a stable drug delivery system. NLCs hold an eminent potential in pharmaceuticals and cosmetics market because of extensive beneficial effects like skin hydration, occlusion, enhanced bioavailability, and skin targeting. This article aims to evoke an interest in the current state of art NLC by discussing their promising assistance in topical drug delivery system. The key attributes of NLC that make them a promising drug delivery system are ease of preparation, biocompatibility, the feasibility of scale up, non-toxicity, improved drug loading, and stability.

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.