Enhanced dermal delivery of diflucortolone valerate using lecithin/chitosan nanoparticles: in-vitro and in-vivo evaluations

A review on natural biopolymers in external drug delivery systems for wound healing and atopic dermatitis

Despite the advantages of topical administration in the treatment of skin diseases, current marketed preparations face the challenge of the skin's barrier effect, leading to low therapeutic effectiveness and undesirable side effects. Hence, in recent years the management of skin wounds, the main morbidity-causing complication in hospital environments, and atopic dermatitis, the most common inflammatory skin disease, has become a great concern. Fortunately, new, more effective, and safer treatments are already under development, with chitosan, starch, silk fibroin, agarose, hyaluronic acid, alginate, collagen, and gelatin having been used for the development of nanoparticles, liposomes, niosomes and/or hydrogels to improve the delivery of several molecules for the treatment of these diseases. Biocompatibility, biodegradability, increased viscosity, controlled drug delivery, increased drug retention in the epidermis, and overall mitigation of adverse effects, contribute to an effective treatment, additionally providing intrinsic antimicrobial and wound healing properties. In this review, some of the most recent success cases of biopolymer-based drug delivery systems as part of nanocarriers, semi-solid hydrogel matrices, or both (hybrid systems), for the management of skin wounds and atopic dermatitis, are critically discussed, including composition and in vitro, ex vivo and in vivo characterization, showing the promise of these external drug delivery systems.

Integrating Artificial Intelligence with Quality by Design in the Formulation of Lecithin/Chitosan Nanoparticles of a Poorly Water-Soluble Drug

The aim of the current study is to explore the potential of artificial intelligence (AI) when integrated with Quality by Design (QbD) approach in the formulation of a poorly water-soluble drug, for its potential use in carcinoma. Silymarin is used as a model drug for its potential effectiveness in liver cancer. A detailed QbD approach was applied. The effect of the critical process parameters was studied on each of the particle size, size distribution, and entrapment efficiency. Response surface designs were applied in the screening and optimization of lecithin/chitosan nanoparticles, to obtain an optimized formula. The release rate was tested, where artificial neural network models were used to predict the % release of the drug from the optimized formula at different time intervals. The optimized formula was tested for its cytotoxicity. A design space was established, with an optimized formula having a molar ratio of 18.33:1 lecithin:chitosan and 38.35 mg silymarin. This resulted in nanoparticles with a size of 161 nm, a polydispersity index of 0.2, and an entrapment efficiency of 97%. The optimized formula showed a zeta potential of +38 mV, with well-developed spherical particles. AI successfully showed high prediction ability of the drug's release rate. The optimized formula showed an enhancement in the cytotoxic effect of silymarin with a decreased IC50 compared to standard silymarin. Lecithin/chitosan nanoparticles were successfully formulated, with deep process and product understanding. Several tools were used as AI which could shift pharmaceutical formulations from experience-dependent studies to data-driven methodologies in the future.

Functional nano-systems for transdermal drug delivery and skin therapy

Transdermal drug delivery is one of the least intrusive and patient-friendly ways for therapeutic agent administration. Recently, functional nano-systems have been demonstrated as one of the most promising strategies to treat skin diseases by improving drug penetration across the skin barrier and achieving therapeutically effective drug concentrations in the target cutaneous tissues. Here, a brief review of functional nano-systems for promoting transdermal drug delivery is presented. The fundamentals of transdermal delivery, including skin biology and penetration routes, are introduced. The characteristics of functional nano-systems for facilitating transdermal drug delivery are elucidated. Moreover, the fabrication of various types of functional transdermal nano-systems is systematically presented. Multiple techniques for evaluating the transdermal capacities of nano-systems are illustrated. Finally, the advances in the applications of functional transdermal nano-systems for treating different skin diseases are summarized.

Recent Trends in Nanocarriers for the Management of Atopic Dermatitis

BACKGROUND

Atopic dermatitis (AD) is a pruritic inflammatory skin condition with increasing global prevalence, almost affecting 15% to 30% of children and 5% of adults. AD results due to a complex interaction between the impaired skin barrier function, allergens, and immunological cells. Topical corticosteroids or calcineurin inhibitors in the form of creams or ointments are the mainstay of therapy, but they have low skin penetration and skin barrier repair efficiency.

OBJECTIVE

The above limitations of conventional dosage forms have motivated the development of nanoformulations of drugs for improved penetration and deposition in the skin for better management of AD.

METHODS

Databases, such as Pubmed, Elsevier, and Google Scholar, were reviewed for the investigations or reviews published related to the title.

RESULTS

The present review discusses the advantages of nanoformulations for the management of AD. Further, it also discusses the various types of topically investigated nanoformulations, i.e., polymeric nanoparticles, inorganic nanoparticles, solid lipid nanoparticles, liposomes, ethosomes, transfersomes, cubosomes, and nanoemulsion for the management of atopic dermatitis. In addition, it also discusses advancements in nanoformulations, such as nanofibres, nanosponges, micelles, and nanoformulations embedded textiles development for the management of AD.

CONCLUSION

The nanoformulations of drugs can be a better alternative for the topical management of AD with enhanced skin penetration and deposition of drugs with reduced systemic side effects and better patient compliance.

Functionalized chitosan nanoparticles for cutaneous delivery of a skin whitening agent: an approach to clinically augment the therapeutic efficacy for melasma treatment

The increase in the production of melanin level inside the skin prompts a patient-inconvenient skin color disorder namely; melasma. This arouses the need to develop efficacious treatment modalities, among which are topical nano-delivery systems. This study aimed to formulate functionalized chitosan nanoparticles (CSNPs) in gel form for enhanced topical delivery of alpha-arbutin as a skin whitening agent to treat melasma. Ionic gelation method was employed to prepare α-arbutin-CSNPs utilizing a 2⁴ full factorial design followed by In vitro, Ex vivo and clinical evaluation of the nano-dispersions and their gel forms. Results revealed that the obtained CSNPs were in the nanometer range with positive zeta potential, high entrapment efficiency, good stability characteristics and exhibited sustained release of α-arbutin over 24 h. Ex vivo deposition of CSNPs proved their superiority in accumulating the drug in deep skin layers with no transdermal delivery. DSC and FTIR studies revealed the successful amorphization of α-arbutin into the nanoparticulate system with no interaction between the drug and the carrier system. The comparative split-face clinical study revealed that α-arbutin loaded CSNPs hydrogels showed better therapeutic efficacy compared to the free drug hydrogel in melasma patients, as displayed by the decrease in: modified melasma area and severity index (mMASI) scores, epidermal melanin particle size surface area (MPSA) and the number of epidermal monoclonal mouse anti–melanoma antigen recognized by T cells-1 (MART-1) positive cells which proved that the aforementioned system is a promising modality for melasma treatment.

PEGylated Lecithin-Chitosan Nanoparticle-Encapsulated Alphα-Terpineol for In Vitro Anticancer Effects

The aim of this study was to fabrication PEGylated lecithin-chitosan nanoparticles (PLC-NPs) as alphα-Terpineol's (αT-PLC-NPs) delivery system and examine its anti-cancer effects. αT-PLC-NPs were synthesized by self-assembling method; after characterization, entrapment efficiency of α-T was measured by HPLC procedure. MTT test was conducted for cytotoxicity evaluation. Chick chorioallantoic membrane (CAM) and quantitative polymerase chain reaction (qPCR) analysis were used to determine the angiogenesis properties, and qPCR, flow cytometry, and acridine orange and propidium iodide (AO/PI) staining were used to evaluate the pro-apoptotic effects of αT-PLC-NPs. Finally, the anti-inflammatory and antibacterial activity of the αT-PLC-NPs was also evaluated. αT-PLC-NPs with a size of 220.8 nm, polydispersity index (PDI) of 0.3, zeta potential of +29.03 mV, and encapsulation efficiency of 82% showed higher inhibitory effect on MCF7 cells (IC₅₀: 750 μg/mL) compared to HFF cells (above 1000 μg/mL). Decreased angiogenesis indices and embryonic growth factors in CAM assay, decreased expression of VEGF and VEGF-R genes, and decreased cell migration showed the inhibitory effect of αT-PLC-NPs on angiogenesis. Increased expression of P53, P21, and caspase9 genes, as well as the results of AO/PI staining along with increasing the number of SubG1 phase cells in flow cytometry, confirmed the pro-apoptotic effects of αT-PLC-NPs. Also, its anti-inflammatory effects were demonstrated by inhibiting the expression of pro-inflammatory cytokines (TNF-α and IL-6). The inhibitory power of αT-PLC-NPs in suppressing gram-positive and negative bacterial strains was demonstrated by disk diffusion (DD), minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods. PLC-NPs are a promising carrier for α-T transfer for preclinical studies.

Self-assembled tacrolimus-loaded lecithin-chitosan hybrid nanoparticles for in vivo management of psoriasis

Lecithin-chitosan hybrid nanoparticles are emerging as a promising nanocarrier for topical drug delivery. They could achieve a maximized encapsulation of hydrophobic drugs due to the lipophilic nature of lecithin that comprises the core while enhancing retention in the upper skin layers using the positively charged polymeric coat of chitosan. The aim of this study is to incorporate tacrolimus; a hydrophobic anti-proliferative agent into lecithin chitosan hybrid nanoparticles by ethanolic injection technique using a suitable co-solvent to enhance encapsulation of the drug and allow a satisfactory release profile in the upper skin layers. Tacrolimus was successfully incorporated into the synthesized particles using olive oil and Tween 80 as co-solvents, with particle size (160.9 nm ± 15.9 and 118.7 nm ± 13.3, respectively) and EE (88.27% ± 4.3 and 66.72% ± 1.8, respectively). The in vitro drug release profile showed a faster release pattern for the Tween 80-containing particles over a 48-hour period (79.98% vs. 35.57%), hence, were selected for further investigation. The hybrid nanoparticles achieved significantly higher skin deposition than the marketed product (63.51% vs. 34.07%) through a 24-hour time interval, particularly, to the stratum corneum and epidermis skin layers. The in vivo results on IMQ-mouse models revealed superior anti-psoriatic efficacy of the synthesized nanoparticles in comparison to the marketed product in terms of visual observation of the skin condition, PASI score and histopathological examination of autopsy skin samples. Additionally, the in vivo drug deposition showed superior skin deposition of the nanoparticles compared to the marketed product (74.9% vs. 13.4%).

Hybrid chitosan-lipid nanoparticles of green tea extract as natural anti-cellulite agent with superior in vivo potency: full synthesis and analysis

The aim of this work is to exploit the advantages of chitosan (CS) as a nanocarrier for delivery of anti-cellulite drug, green tea extract (GTE), into subcutaneous adipose tissue. Primarily, analysis of herbal extract was conducted via newly developed and validated UPLC method. Ionic gelation method was adopted in the preparation of nanoparticles where the effect lecithin was investigated resulting in the formation of hybrid lipid-chitosan nanoparticles. Optimal formula showed a particle size of 292.6 ± 8.98 nm, polydispersity index of 0.253 ± 0.02, zeta potential of 41.03 ± 0.503 mV and an entrapment efficiency percent of 68.4 ± 1.88%. Successful interaction between CS, sodium tripolyphosphate (TPP) and lecithin was confirmed by Fourier-transform infrared spectroscopy, differential scanning calorimetry and X-ray diffraction. Morphological examination was done using transmission electron microscope and scanning electron microscope confirmed spherical uniform nature of GTE load CS-TPP nanoparticles. Ex vivo permeation study revealed permeability enhancing activity of the selected optimal formula due to higher GTE deposition in skin in comparison to GTE solution. Moreover in vivo study done on female albino Wistar rats carried out for 21 days proved successful potential anti-cellulite activity upon its application on rats’ skin. Histological examination showed significant reduction of adipocyte perimeter and area and fat layer thickness. Results of the current study demonstrated that the developed GTE-loaded CS-TPP nanoparticle comprised of chitosan and lecithin showed permeability enhancing activity along with the proven lipolytic effect of green tea represent a promising delivery system for anti-cellulite activity.

Nano intervention in topical delivery of corticosteroid for psoriasis and atopic dermatitis-a systematic review

Atopic dermatitis (AD) and psoriasis are highly prevalent, complex, chronic inflammatory skin diseases that immensly affect the patient's quality of life. While there is no definitive cure for these conditions, suppressive medications aim at managing the symptoms of these diseases. The application of emollients accompanied by symptomatic anti-inflammatory therapy consisting of topical corticosteroids (TCS) is extensively employed for controlling the symptoms among general practitioners making this therapeutic class an indispensable pillar of dermatotherapeutics. The first TCS, hydrocortisone (HC) introduced in the early 1950s led to the development of different steroidal moieties of varying potencies by inducing chemical modifications to the basic steroid structure. The wide spectrum of the available range of formulations and potency provides flexibility to treat all patient groups, different phases of the diseases, and different anatomical sites. Conventional TCS therapy suffers from drawbacks such as low drug permeation and retention rate. Thus, novel nanoformulations have been developed to overcome these problems. This review provides an insight into the current state of nanocarrier-mediated topical delivery of corticosteroids monotherapy and combination therapy with special emphasis on targeting psoriasis and AD.

Recent perspectives of nanotechnology in burn wounds management: a review

OBJECTIVE

The burden of the management of problematic skin wounds characterised by a compromised skin barrier is growing rapidly. Almost six million patients are affected in the US alone, with an estimated market of $25 billion annually. There is an urgent requirement for efficient mechanism-based treatments and more efficacious drug delivery systems. Novel strategies are needed for faster healing by reducing infection, moisturising the wound, stimulating the healing mechanisms, speeding up wound closure and reducing scar formation.

METHODS

A systematic review of qualitative studies was conducted on the recent perspectives of nanotechnology in burn wounds management. Pubmed, Scopus, EMBASE, CINAHL and PsychINFO databases were all systematically searched. Authors independently rated the reporting of the qualitative studies included. A comprehensive literature search was conducted covering various resources up to 2018-2019. Traditional techniques aim to simply cover the wound without playing any active role in wound healing. However, nanotechnology-based solutions are being used to create multipurpose biomaterials, not only for regeneration and repair, but also for on-demand delivery of specific molecules. The chronic nature and associated complications of nonhealing wounds have led to the emergence of nanotechnology-based therapies that aim at facilitating the healing process and ultimately repairing the injured tissue.

CONCLUSION

Nanotechnology-based therapy is in the forefront of next-generation therapy that is able to advance wound healing of hard-to-heal wounds. In this review, we will highlight the developed nanotechnology-based therapeutic agents and assess the viability and efficacy of each treatment. Herein we will explore the unmet needs and future directions of current technologies, while discussing promising strategies that can advance the wound-healing field.

Self-Assembled chitosan/phospholipid nanoparticles: from fundamentals to preparation for advanced drug delivery

With the development of nanotechnology, self-assembled chitosan/phospholipid nanoparticles (SACPNs) show great promise in a broad range of applications, including therapy, diagnosis, in suit imaging and on-demand drug delivery. Here, a brief review of the SACPNs is presented, and its critical underlying formation mechanisms are interpreted with an emphasis on the intrinsic physicochemical properties. The state-of-art preparation methods of SACPNs are summarized, with particular descriptions about the classic solvent injection method. Then SACPNs microstructures are characterized, revealing the unique spherical core-shell structure and the drug release mechanisms. Afterwards, a comprehensive and in-depth depiction of their emerging applications, with special attention to drug delivery areas, are categorized and reviewed. Finally, conclusions and outlooks on further advancing the SACPNs toward a more powerful and versatile platform for investigations covering from fundamental understanding to developing multi-functional drug delivery systems are discussed.

Development of Lecithin/Chitosan Nanoparticles for Promoting Topical Delivery of Propranolol Hydrochloride: Design, Optimization and In-Vivo Evaluation

Propranolol (PPL) administered orally is considered as the first line drug for the treatment of infantile hemangioma, however several systemic adverse effects limit its use. For this reason, our work tackles the development and evaluation of PPL loaded chitosan nanoparticles (NPs), as an effective alternative for the treatment of infantile hemangioma. PPL -NPs were prepared using the double emulsion technique and the influence of the formulation variables on drug entrapment efficiency (EE), particle size (PS), percent released after 24 h (%R_24h) and zeta potential (ZP) were optimized using full factorial design. Two systems, namely F3 and F28 showing highest E.E., ZP and %R_24h with lowest PS, were fully characterized for DSC and TEM and incorporated into hydrogel with adequate viscosity. After ensuring safety for the selected nanoparticle, the hydrogel containing the optimized system was applied topically to rats. The in-vivo skin deposition in rats showed an accumulation of propranolol from the lecithin/chitosan nanocarrier by 1.56-1.91-fold when compared to the drug solution. The obtained result was further supported by the confocal laser scanning microscopy which showed fluorescence across the skin. PPL-HCL-loaded lecithin/chitosan nanoparticles could be considered as a potential candidate for treating infantile hemangiomas (IH) by maintaining therapeutic concentration topically while minimizing systemic side effects.

Self-Assembled Lecithin/Chitosan Nanoparticles Based on Phospholipid Complex: A Feasible Strategy to Improve Entrapment Efficiency and Transdermal Delivery of Poorly Lipophilic Drug

PURPOSE

Lecithin/chitosan nanoparticles have shown great promise in the transdermal delivery of therapeutic agents. Baicalein, a natural bioactive flavonoid, possesses multiple biological activities against dermatosis. However, its topical application is limited due to its inherently poor hydrophilicity and lipophilicity. In this study, the baicalein-phospholipid complex was prepared to enhance the lipophilicity of baicalein and then lecithin/chitosan nanoparticles loaded with the baicalein-phospholipid complex were developed to improve the transdermal retention and permeability of baicalein.

METHODS

Lecithin/chitosan nanoparticles were prepared by the solvent-injection method and characterized in terms of particle size distribution, zeta potential, and morphology. The in vitro release, the ex vivo and in vivo permeation studies, and safety evaluation of lecithin/chitosan nanoparticles were performed to evaluate the effectiveness in enhancing transdermal retention and permeability of baicalein.

RESULTS

The lecithin/chitosan nanoparticles obtained by the self-assembled interaction of chitosan and lecithin not only efficiently encapsulated the drug with high entrapment efficiency (84.5%) but also provided sustained release of baicalein without initial burst release. Importantly, analysis of the permeation profile ex vivo and in vivo demonstrated that lecithin/chitosan nanoparticles prolonged the retention of baicalein in the skin and efficiently penetrated the barrier of stratum corneum without displaying skin irritation.

CONCLUSION

These results indicate the potential of drug-phospholipid complexes in enhancing the entrapment efficiency and self-assembled lecithin/chitosan nanoparticles based on phospholipid complexes in the design of a rational transdermal delivery platform to improve the efficiency of transdermal therapy by enhancing its percutaneous retention and penetration in the skin.

Chitosan oligosaccharide-mediated attenuation of LPS-induced inflammation in IPEC-J2 cells is related to the TLR4/NF-κB signaling pathway

The protective mechanism of chitosan oligosaccharide (COS) against lipopolysaccharides (LPS) -induced inflammatory responses in IPEC-J2 and in mice with DSS dextran sulfate sodium (DSS) -induced colitis is reported. Upon exposure to LPS, the proliferation rate of IPEC-J2 cells markedly decreased, and epithelial cell integrity was compromised. However, COS pretreatment significantly reduced these changes. Low-concentration (200 μg/mL) COS up-regulated Toll-like receptor 4 (TLR4) and nuclear p65 expression, but inhibited LPS-induced expression of nuclear p65, IL-6, and IL-8. Addition of the TLR4 inhibitor reduced nuclear p65, IL-6, and IL-8 expression in IPEC-J2 cells exposed to COS or LPS alone, and a slight up-regulation in nuclear p65 was observed in COS and LPS co-treated cells. Medium-dose COS (600 mg/kg/d) protected against DSS-induced colitis, in which TLR4 and nuclear p65 expression levels were decreased. We postulate that the prevention of both LPS- and DSS -induced inflammatory responses in IPEC-J2 cells and mice by COS are related to the inhibition of the TLR4/NF-κB signaling pathway.

Formulation and Evaluation of Organogels Containing Hyaluronan Microparticles for Topical Delivery of Caffeine

Cellulite is a dermal disorder including the extracellular matrix, the lymphatic and microcirculatory systems and the adipose tissue. Caffeine is used as the active moiety depending its preventive effect on localization of fat in the cellular structure. Hyaluronic acid (hyaluronan-HA) is a natural constituent of skin that generates formation and poliferation of new cells having a remarkable moisturizing ability. The aim of this study is to formulate HA microparticles loaded with caffeine via spray-drying method. Resulting microparticle formulations (33.97 ± 0.3 μm, span < 2, 88.56 ± 0.42% encapsulation efficiency) were distributed in lecithin organogels to maintain the proper viscosity for topical application. Following the characterization and cell culture studies, in vitro drug release and ex vivo permeation studies were performed. The accumulated amount of caffeine was twice higher than the aqueous solution for the microparticle-loaded organogels at 24 h (8262,673 μg/cm²versus 4676,691 μg/cm²). It was related to the sustained behaviour of caffeine release from the microparticles. As a result, lecithin organogel containing HA-encapsulated microparticles could be considered as suitable candidate formulations for efficient topical drug delivery system of caffeine. In addition to that, synergistic effect of this combination appears as a promising approach for long-acting treatment of cellulite.

Dual-Prevention for UV-Induced Skin Damage: Incorporation of Melatonin-Loaded Elastic Niosomes into Octyl Methoxycinnamate Pickering Emulsions

Incorporation of antioxidants into sunscreens is a logical approach, yet co-delivery of them with UV filters is a challenge. Here, we purposed a combination therapy, in which the chemical UV filter, octyl methoxycinnamate, was accumulated on upper skin while the antioxidant, melatonin, can penetrate deeper layers to show its effects. Melatonin-loaded elastic niosomes and octyl methoxycinnamate Pickering emulsion were prepared separately. Lyophilized elastic niosomes were dispersed into the Pickering emulsion to prepare the proposed combination formulation. The characterization studies of the formulations revealed that elastic niosomes can be prepared with tunable nanometer sizes, whereas Pickering emulsions can encapsulate the UV filter in micrometer-sized droplets. Melatonin-loaded elastic niosomes prepared with Tween80/Span80 mixture were 146 nm with a PI of 0.438, and 58.42% entrapment efficiency was achieved. The mean diameter size of the combination formulation was 27.8 μm. Ex vivo permeation studies revealed that 7.40% of octyl methoxycinnamate and 58% of melatonin were permeated through the rat skin while 27.6% octyl methoxycinnamate and 37% of melatonin accumulated in the skin after 24 h. Cell culture studies with real-time cell analyzer showed that the proposed formulation consist of melatonin-loaded elastic niosomes and octyl methoxycinnamate Pickering emulsion had no negative effect on the cell proliferation and viability. According to α,α-diphenyl-β-picrylhydrazyl free radical scavenging method, the proposed formulation showed as high antioxidant activity as melatonin itself. It is concluded that the proposed formulation would be a promising dual therapy for UV-induced skin damage with co-delivery strategy.

Chitosan nanoparticles for nitric oxide delivery in human skin

The use of nanoparticle-based transdermal delivery systems is a promising approach to efficiently carry and deliver therapeutic agents for dermal and systemic administration. Nitric oxide (NO) is a key molecule that plays important roles in human skin such as the control of skin homeostasis, skin defense, control of dermal blood flow, and wound healing. In addition, human skin contains stores of NO derivatives that can be mobilized and release free NO upon UV irradiation with beneficial cardiovascular effects, for instance the control of blood pressure. In this work, the NO donor precursor glutathione (GSH) was encapsulated (encapsulation efficiency of 99.60%) into ultra-small chitosan nanoparticles (CS NPs) (hydrodynamic size of 30.65 ± 11.90 nm). GSH-CS NPs have a core-shell structure, as revealed by atomic force microscopy and X-ray photoelectron spectroscopy, in which GSH is protected in the nanoparticle core. Nitrosation of GSH by nitrous acid led to the formation of the NO donor S-nitrosogluthathione (GSNO) into CS NPs. The GSNO release from the CS NPs followed a Fickian diffusion described by the Higuchi mathematical model. Topical application of GSNO-CS NPs in intact human skin significantly increased the levels of NO and its derivatives in the epidermis, as assayed by confocal microscopy, and this effect was further enhanced by skin irradiation with UV light. Therefore, NO-releasing CS NPs are suitable materials for transdermal NO delivery to local and/or systemic therapies.

Chitosan-Based Multifunctional Platforms for Local Delivery of Therapeutics

Chitosan has been widely used as a key biomaterial for the development of drug delivery systems intended to be administered via oral and parenteral routes. In particular, chitosan-based microparticles are the most frequently employed delivery system, along with specialized systems such as hydrogels, nanoparticles and thin films. Based on the progress made in chitosan-based drug delivery systems, the usefulness of chitosan has further expanded to anti-cancer chemoembolization, tissue engineering, and stem cell research. For instance, chitosan has been used to develop embolic materials designed to efficiently occlude the blood vessels by which the oxygen and nutrients are supplied. Indeed, it has been reported to be a promising embolic material. For better anti-cancer effect, embolic materials that can locally release anti-cancer drugs were proposed. In addition, a complex of radioactive materials and chitosan to be locally injected into the liver has been investigated as an efficient therapeutic tool for hepatocellular carcinoma. In line with this, a number of attempts have been explored to use chitosan-based carriers for the delivery of various agents, especially to the site of interest. Thus, in this work, studies where chitosan-based drug delivery systems have successfully been used for local delivery will be presented along with future perspectives.

Antioxidant and Antibacterial Potential of Silver Nanoparticles: Biogenic Synthesis Utilizing Apple Extract

The advancement of the biological production of nanoparticles using herbal extracts performs a significant role in nanotechnology discipline as it is green and does not engage harsh chemicals. The objective of the present investigation was to extract flavonoids in the mode of apple extract and synthesize its silver nanoparticles and ultimately nanoparticles loading into hydrogels. The presence of flavonoids in apple extract was characterized by preliminary testing like dil. ammonia test and confirmatory test by magnesium ribbon test. The synthesized silver nanoparticles were characterized using UV spectroscopy, particle size and surface morphology, and zeta potential. Silver nanoparticles loaded hydrogels were evaluated for physical appearance, pH, viscosity, spreadability, porosity, in vitro release, ex vivo permeation, and antibacterial (E. coli and S. aureus) and antioxidant studies (DPPH radical scavenging assay). Well dispersed silver nanoparticles below were observed in scanning electron microscope image. Hydrogels displayed in vitro release of 98.01%  ±  0.37% up to 24 h and ex vivo permeation of 98.81  ±  0.24% up to 24 h. Hydrogel effectively inhibited the growth of both microorganism indicating good antibacterial properties. The value of percent radical inhibition was 75.16%  ±  0.04 revealing its high antioxidant properties. As an outcome, it can be concluded that antioxidant and antiageing traits of flavonoids in apple extract plus biocidal feature of silver nanoparticles can be synergistically and successfully utilized in the form of hydrogel.

Kaempferol loaded lecithin/chitosan nanoparticles: preparation, characterization, and their potential applications as a sustainable antifungal agent

Flavonoid compounds are strong antioxidant and antifungal agents but their applications are limited due to their poor dissolution and bioavailability. The use of nanotechnology in agriculture has received increasing attention, with the development of new formulations containing active compounds. In this study, kaempferol (KAE) was loaded into lecithin/chitosan nanoparticles (LC NPs) to determine antifungal activity compared to pure KAE against the phytopathogenic fungus Fusarium oxysporium to resolve the bioavailability problem. The influence of formulation parameters on the physicochemical properties of KAE loaded lecithin chitosan nanoparticles (KAE-LC NPs) were studied by using the electrostatic self-assembly technique. KAE-LC NPs were characterized in terms of physicochemical properties. KAE has been successfully encapsulated in LC NPs with an efficiency of 93.8 ± 4.28% and KAE-LC NPs showed good physicochemical stability. Moreover, in vitro evaluation of the KAE-LC NP system was made by the release kinetics, antioxidant and antifungal activity in a time-dependent manner against free KAE. Encapsulated KAE exhibited a significantly inhibition efficacy (67%) against Fusarium oxysporium at the end of the 60 day storage period. The results indicated that KAE-LC NP formulation could solve the problems related to the solubility and loss of KAE during use and storage. The new nanoparticle system enables the use of smaller quantities of fungicide and therefore, offers a more environmentally friendly method of controlling fungal pathogens in agriculture.

Self-assembled lecithin/chitosan nanoparticles for oral insulin delivery: preparation and functional evaluation

Purpose

Here, we investigated the formation and functional properties of self-assembled lecithin/chitosan nanoparticles (L/C NPs) loaded with insulin following insulin–phospholipid complex preparation, with the aim of developing a method for oral insulin delivery.

Methods

Using a modified solvent-injection method, insulin-loaded L/C NPs were obtained by combining insulin–phospholipid complexes with L/C NPs. The nanoparticle size distribution was determined by dynamic light scattering, and morphologies were analyzed by cryogenic transmission electron microscopy. Fourier transform infrared spectroscopy analysis was used to disclose the molecular mechanism of prepared insulin-loaded L/C NPs. Fast ultrafiltration and a reversed-phase high-performance liquid chromatography assay were used to separate free insulin from insulin entrapped in the L/C NPs, as well as to measure the insulin-entrapment and drug-loading efficiencies. The in vitro release profile was obtained, and in vivo hypoglycemic effects were evaluated in streptozotocin-induced diabetic rats.

Results

Our results indicated that insulin-containing L/C NPs had a mean size of 180 nm, an insulin-entrapment efficiency of 94%, and an insulin-loading efficiency of 4.5%. Cryogenic transmission electron microscopy observations of insulin-loaded L/C NPs revealed multilamellar structures with a hollow core, encircled by several bilayers. In vitro analysis revealed that insulin release from L/C NPs depended on the L/C ratio. Insulin-loaded L/C NPs orally administered to streptozotocin-induced diabetic rats exerted a significant hypoglycemic effect. The relative pharmacological bioavailability following oral administration of L/C NPs was 6.01%.

Conclusion

With the aid of phospholipid-complexation techniques, some hydrophilic peptides, such as insulin, can be successfully entrapped into L/C NPs, which could improve oral bioavailability, time-dependent release, and therapeutic activity.

Amphotericin-B entrapped lecithin/chitosan nanoparticles for prolonged ocular application

Fungal keratitis is the major cause of vision loss worldwide. Amphotericin-B is considered as the drug of choice for fungal infections. However, its use in ophthalmic drug delivery is limited by the low precorneal residence at ocular surface as a result of blinking reflex, tear turnover and nasopharyngeal drainage. We report Amphotericin-B loaded lecithin/chitosan nanoparticles for prolonged ocular application. The prepared nanoparticles were in the size range of 161.9-230.5 nm, entrapment efficiency of 70-75%, theoretical drug loading of 5.71% with positive zeta potential of 26.6-38.3 mV. As demonstrated by antifungal susceptibility against Candida albicans and Aspergillus fumigatus, nanoparticles were more effective than marketed formulation. They exhibited pronounced mucoadhesive properties. In-vivo pharmacokinetic studies in New Zealand albino rabbit eyes indicated improved bioavailablity (∼ 2.04 fold) and precorneal residence time (∼ 3.36 fold) by nanoparticles prepared from low molecular weight chitosan as compared with marketed formulation.

Effective topical delivery systems for corticosteroids: dermatological and histological evaluations

Atopic dermatitis (AD) is a chronic and relapsing skin disease with severe eczematous lesions. Long-term topical corticosteroid treatment can induce skin atrophy, hypopigmentation and transepidermal water loss (TEWL) increase. A new treatment approach was needed to reduce the risk by dermal targeting. For this purpose, Betamethasone valerate (BMV)/Diflucortolone valerate (DFV)-loaded liposomes (220-350 nm) were prepared and incorporated into chitosan gel to obtain adequate viscosity (∼13 000 cps). Drugs were localized in stratum corneum + epidermis of rat skin in ex-vivo permeation studies. The toxicity was assessed on human fibroblast cells. In point of in-vivo studies, pharmacodynamic responses, treatment efficacy and skin irritation were evaluated and compared with previously prepared nanoparticles. Liposome/nanoparticle in gel formulations produced higher paw edema inhibition in rats with respect to the commercial cream. Similar skin blanching effect with commercial creams was obtained via liposome in gels although they contain 10 times less drug. Dermatological scoring results, prognostic histological parameters and suppression of mast cell numbers showed higher treatment efficiency of liposome/nanoparticle in gel formulations in AD-induced rats. TEWL and erythema measurements confirmed these results. Overview of obtained results showed that liposomes might be an effective and safe carrier for corticosteroids in skin disease treatment.

Nanomedicine strategies for targeting skin inflammation

Topical treatment of skin diseases is an attractive strategy as it receives high acceptance from patients, resulting in higher compliance and therapeutic outcomes. Recently, the use of variable nanocarriers for dermal application has been widely explored, as they offer several advantages compared with conventional topical preparations, including higher skin penetration, controlled and targeted drug delivery and the achievement of higher therapeutic effects. This article will focus on skin inflammation or dermatitis as it is one of the most common skin problems, describing the different types and causes of dermatitis, as well as the typical treatment regimens. The potential use of nanocarriers for targeting skin inflammation and the achievement of higher therapeutic effects using nanotechnology will be explored.

Drug delivery systems, CNS protection, and the blood brain barrier

Present review highlights various drug delivery systems used for delivery of pharmaceutical agents mainly antibiotics, antineoplastic agents, neuropeptides, and other therapeutic substances through the endothelial capillaries (BBB) for CNS therapeutics. In addition, the use of ultrasound in delivery of therapeutic agents/biomolecules such as proline rich peptides, prodrugs, radiopharmaceuticals, proteins, immunoglobulins, and chimeric peptides to the target sites in deep tissue locations inside tumor sites of brain has been explained. In addition, therapeutic applications of various types of nanoparticles such as chitosan based nanomers, dendrimers, carbon nanotubes, niosomes, beta cyclodextrin carriers, cholesterol mediated cationic solid lipid nanoparticles, colloidal drug carriers, liposomes, and micelles have been discussed with their recent advancements. Emphasis has been given on the need of physiological and therapeutic optimization of existing drug delivery methods and their carriers to deliver therapeutic amount of drug into the brain for treatment of various neurological diseases and disorders. Further, strong recommendations are being made to develop nanosized drug carriers/vehicles and noninvasive therapeutic alternatives of conventional methods for better therapeutics of CNS related diseases. Hence, there is an urgent need to design nontoxic biocompatible drugs and develop noninvasive delivery methods to check posttreatment clinical fatalities in neuropatients which occur due to existing highly toxic invasive drugs and treatment methods.

Comprehensive review on additives of topical dosage forms for drug delivery

Skin is the largest organ of the human body and plays the most important role in protecting against pathogen and foreign matter. Three important modes such as topical, regional and transdermal are widely used for delivery of various dosage forms. Among these modes, the topical dosage forms are preferred because it provides local therapeutic activity when applied to the skin or mucous membranes. Additives or pharmaceutical excipients (non-drug component of dosage form) are used as inactive ingredients in dosage form or tools for structuring dosage forms. The main use of topical dosage form additives are controling the extent of absorption, maintaining the viscosity, improving the stability as well as organoleptic property and increasing the bulk of the formulation. The overall goal of this article is to provide the clinician with information related to the topical dosage form additives and their current major applications against various diseases.