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The natural capability shown by cationic vesicles in interacting with negatively charged surfaces or biomolecules has recently attracted increased interest. Important pharmacological advantages include the selective targeting of the tumour vasculature, the promotion of permeation across cell membranes, as well as the influence of cationic vesicles on drug delivery. Accordingly, cationic amphiphiles derived from amino acids may represent an alternative to traditional synthetic cationic surfactants due to their lower cytotoxicity. The importance of a synthesized lysine-based gemini surfactant (labelled C 6 (LL) 2 ) was evaluated in drug delivery by designing cationic niosomes as usable pharmaceutical tools of chemotherapeutics and antibiotics, respectively like methotrexate and tetracycline. The influence of formulation factors on the vesicles’ physical-chemical properties, drug entrapment efficiency, in vitro release and ex-vivo skin permeation were investigated. A niosomal gel containing the gemini surfactant was also tested as a viable multi-component topical formulation. Results indicate that in the presence of cholesterol, C 6 (LL) 2 was able to form stable and nanosized niosomes, loading hydrophilic or hydrophobic molecules. Furthermore, in vitro release studies and ex-vivo permeation profiles showed that C 6 (LL) 2 -based vesicles behave as sustained and controlled delivery systems in the case of parenteral administration, and as drug percutaneous permeation enhancers after topical application. Finally, cationic C 6 (LL) 2 acts as a carrier constituent, conferring peculiar and interesting functionality to the final formulation. [ABSTRACT FROM AUTHOR]

Delivering chemotherapy specifically, effectively and safely to tumor remains a significant challenge in recent years. Although cancer cells are more vulnerable than normal to the effect of anticancer agents, these drugs are non-selective and can cause injury to normal tissues. Different approaches i.e. passive, active and magnetic targeting, smart devices with appropriate stimuli-sensitive properties or drugs combinations, have been already proposed as single methods, contributing to minimize severe side effects and enhancing tumor-targeting efficacy. Often, the use of a single strategy is not sufficient, whereby multi-functional approach has been suggested as further evolution of traditional “magic bullet” proposed in the early 1900s by Paul Ehrlich. Among the macromolecular systems useful for targeted drug delivery, liposomes and niosomes are the most extensively studied and they own the most suitable characteristics to be converted in multi-functional devices. Liposomes and niosomes are nanovesicles that contain amphiphilic molecules arranged in concentric bilayers, delimitating an aqueous core. These vesicular carriers are very versatile, since they can be differently designed and modified in such a way that they exhibit combinations of the following properties: longevity in blood, specific target to the tumor, respond to internal/external stimuli, promotion of drug intracellular delivery. This review will focus on the potential of multi-functional vesicular nanocarriers in cancer therapy, analizing each combination of targeting strategies, stimuli-sensitivity and drug combinations and giving an exhaustive collection of recent investigations. Many multi-functional vesicular devices have shown great promise in clinical application, indicating broad potential as therapeutics in the near future, but more needs to be done. The development of more specific and efficient carriers for a personalized cancer therapy is the next challenge. [ABSTRACT FROM AUTHOR]

Ferrogels (or magnetic hydrogels) are cross-linked polymer networks containing magnetic nanoparticles: they are mechanically soft and highly elastic and at the same time they exhibit a strong magnetic response. Our work focuses on an combinatorial strategy to improve the efficacy of 5-Fluorouracil (5-FU) assisted chemotherapy, by developing novel multifunctional pH-sensitive ferrogels . We designed gels based on N , N ′-dimethylacrylamide monomers polymerized in presence of methacrylic acid or 2-aminoethyl methacrylate hydrochloride, containing ferro-nanoparticles. The influence of polymeric matrix composition and exposition to magnetic field (MF) on swelling behavior and drugs release were investigated at pH 7.4 and 5. In particular, the magnetic field was obtained by using permanent magnetic bar (0.25 T) or electromagnet (0.5 and 1.2 T), with the aim to analyze quantitatively the magnetic effects. A strong influence of the magnetic field on ferrogels properties have been observed. Swelling analysis indicated a dependence on both pH and network composition, reaching a maximum at pH 7.4, for formulations containing methacrylic acid, while the application of MF appeared to decrease the swelling percentages. Release profiles of 5-FU showed effective modulation in release by application of MF: drug release is always higher in the presence of a magnetic field and generally increases with its intensity. The combining effect of pH sensitive properties and application of MF improved the performance of the systems. Results showed that our ferrogels may be technologically applicable as devices for delivery of 5-FU in a controllable manner. [ABSTRACT FROM AUTHOR]

The aim of this study was to improve the transdermal permeation of sulfadiazine sodium, employing synergistic combination of surfactants (in the form of niosomes) and additives with different number of hydroxylic groups, (following referred to as “alcohol”), as component of the bilayer. In particular the effect of different concentration of each alcohol (ethanol, propylene glycol or glycerol, from 5%, to 40% v/v) on niosomes size and distribution, drug entrapment efficiencies and ex vivo drug percutaneous permeation were evaluated, identifying formulations giving the best performances. The findings revealed that the presence of alcohol critically affect the physico-chemical properties of niosomes, with regards to dimensions, drug encapsulation and permeation. Vesicular size increased with the amount of alcohol and at the same alcohol concentration, follow the sequence ethanol > propylene glycol > glycerol. Loaded niosomes were larger than empty ones. Low E % values were found for ethanol, even less in propylene glycol and glycerol based samples, confirming that the chemical structure of the alcohol and its physico-chemical properties, affected the sulfadiazine entrapment efficiency. The comparative evaluation of percutaneous permeation profiles showed that the cumulative amount of permeated drug increases with alcohol concentration up to 20% v/v. Higher concentration (40% v/v) resulted in a strong decrease of the potential skin permeation. Best performances were obtained with glycerol. In all cases ex vivo sulfadiazine percutaneous permeations are controlled and improved respect to the corresponding free drug solutions and traditional niosomes used as controls. [ABSTRACT FROM AUTHOR]

Highlights: [•] Design of niosomal systems containing lipophilic antioxidants for cosmeceutical applications. [•] Evaluation of the effect of antioxidants co-encapsulation on the niosomes properties. [•] Studies of the antioxidant properties and the in vitro percutaneous permeations of antioxidants from the carriers. [Copyright &y& Elsevier]

Highlights: [•] Design of novel niosomal formulations containing nutritional supplements. [•] Evaluation of the effect of the active molecules co-encapsulation on the properties of the carriers. [•] Studies on the antioxidant properties and releasing capability of gallic acid, ascorbic acid, curcumin and quercetin. [Copyright &y& Elsevier]

Abstract: We designed novel niosomes based on alkyl glucopyranoside surfactants and containing methotrexate as anticancer drug, to be used in the pharmaceutical field. The effects of surfactants with chains of different length on niosome size and their distribution, drug entrapment efficiencies and in vitro drug release were determined. Systems made of alkyl glucopyranosides and cholesterol form vesicles whose average size scales with the alkyl chains length of such surfactants. Vesicles size ranges between 300 and 500nm, with low polydispersity index. In addition, the hemolytic activity of alkyl glucopyranosides as surfactant solutions or vesicular formulations was studied and compared, to identify possible structure–activity relationships. High methotrexate entrapment efficiency was obtained, confirming significant interactions between the drug and the niosomal matrices. After 24h the amount of methotrexate released from niosomal formulations is effectively delayed, compared to the free drug in solution. Hemolytic tests show that sugar-based surfactants are more hemolytic the longer is their alkyl chain. When the surfactants are in vesicular form, the reverse behavior holds. It was also inferred that vesicle formation reduces the surfactant toxicity. These niosomal formulations can be used as methotrexate delivery systems in anticancer therapy. [Copyright &y& Elsevier]

Abstract: The central motivation for this study was to evaluate if the increased hydrophilic drug permeation across the skin, which is always observed in presence of vesicular systems, is dependent on the structural organization of niosomes, that are used to transport the active molecules, or if it is only dependent on the surfactant dual nature. To answer this question, non-ionic surfactants belonging to the class of Pluronic and sucrose esters were used both as components of niosomal systems or in the form of sub-micellar solutions. The obtained niosomes were characterized by their entrapment efficiency, size and morphology. The enhancing effect of niosomes on the ex vivo percutaneous penetration of a model drug was investigated using a Franz-type diffusion chamber and compared to that obtained by using sub-micellar solution of surfactant or achieving pretreatment of the skin with surfactants’ sub-micellar solution or empty niosomes. The results suggest that the surfactants used in this study could be considered as percutaneous permeation enhancers only when they are in the form of drug-loaded vesicular systems: no percutaneous promotion was achieved by using sub-micellar solution containing free Sulfadiazine sodium salt or performing pretreatment with empty niosomes or sub-micellar solutions of the surfactant. In our experiments, only niosomes act as effective transdermal drug delivery systems. [Copyright &y& Elsevier]

Abstract: The objectives of our study were to evaluate the ability of Pluronic L64 surfactant to give niosomal systems alone or after its functionalization with acrylic groups. The achieved formulations were tested for the percutaneous permeation of Sodium Diclofenac as model drug. In vitro experiments were conducted by Franz diffusion cells, using rabbit ear skin. Data recorded over 24h were compared with those obtained from the drug solution, as control. In addition, the stability of niosomes was improved polymerizing the acryloyl groups of the monomers, because, as reported in the literature, polymerized vesicles maintain their shape for long periods of time, and show remarkable increase in drug encapsulation efficiency. Mean vesicles diameter, drug entrapment efficiency, percutaneous permeation and release profiles were investigated for all vesicles with different composition. The results indicated an increase in mean vesicles diameter and entrapment efficiency with the increase of polymerizable moieties amount. These properties were found to be more evident when the vesicles were polymerized. In addition cytotoxic effects were estimated. The results of this study showed that niosomes based on commercial, functionalized or a mixture of both Pluronic L64 surfactants can be used to achieve retarded release and to enhance the permeation of Sodium Diclofenac, without incurring unacceptable toxicity. [Copyright &y& Elsevier]

In this study, we report the results of our investigations on the percutaneous permeation profiles of Diclofenac sodium, Paracetamol, Propanolol hydrochloride, and α-Tocopherol from the different lyotropic liquid crystalline phases obtained by Pluronic P105/water mixtures, in order to understand if the particular assembly shown in the formulations could influence the delivery across the skin. Recent studies have focused on the Pluronic liquid crystalline phases to evaluate the potential use of these phases in drug delivery, but no comparative investigation has been yet performed on the drug permeation from the different liquid crystalline phases obtained by the same Pluronic surfactant. The cubic, hexagonal, and lamellar mesophases (loading the above-mentioned drug) were characterized by Deuterium Nuclear Magnetic Resonance spectroscopy and Polarized Optical Microscopy observations. Results revealed that the liquid crystalline gel microscopic structure obtained in the different formulations drastically affects the drug percutaneous availability. As a consequence these systems could be proposed as novel transdermal drug delivery systems. [ABSTRACT FROM AUTHOR]

Abstract: Colon-targeted delivery devices based on methacrylic functionalized Tween monomer networks, useful for 5-FU or Ferulic acid site-specific release, were synthesized. The basic design consists of methacrylic functionalized Tween monomer-based networks prepared with or without acrylic acid as co-monomer. The swelling behaviour and loaded drugs release from these gels was studied as a function of pH. The devices showed a strong pH-dependent swelling behaviour, allowing a maximum release at pH 7.4. The acrylic acid introduction increased the polymeric gels pores size, as evidenced by the loading efficiency increase, but also reduced the amount of released drug in basic media compared to analogous network not containing the co-monomer. This behaviour, already found in the matrix swelling, could be attributed to a slower hydrolysis kinetics of the ester bond in functionalized Tween monomers, which implies a reduced ability to absorb water from a basic medium, resulting in a lower capacity to release the loaded drug. Since our device possesses a maximum drug release in the media at pH 7.4, it could be used for colon-targeted drug delivery of both 5-FU and Ferulic acid. [Copyright &y& Elsevier]

Abstract: A commercial sucrose cocoate surfactant was used to obtain a new vesicular system for transdermal drug delivery. The preparation, the dimensional and morphological characterizations and the skin permeation profile of these new niosomes were evaluated. Moreover we studied the possible employment of mixture of sucrose cocoate and cholesterol at different weigh ratios for the vesicles preparation and we analyzed the influence of cholesterol on niosomes properties. Diclofenac and Sulfadiazine were used as model drugs. Results suggest that sucrose cocoate was able to form vesicles in the presence or not of cholesterol and the addition of cholesterol leads to a variation of size: larger vesicles were obtained in the absence of cholesterol both in empty and drug-loaded niosomes. All vesicles were spherical and regular in shape. In vitro skin permeation profiles were significantly higher than the free drug solution, indicating the favourable relations between skin and niosomes. The faster release of the drug was found for niosomes with no cholesterol or with a reduced amount of this membrane additive, in particular the optimal formulation was that in which the cholesterol content was about 27wt% of total lipid amount: probably this value is a good compromise between the membrane stability and its deformation capacity, allowing a higher drug permeation across the skin. [Copyright &y& Elsevier]

Abstract: The synthesis and characterisation of new surfactants with peculiar physical–chemical properties are amongst the most promising and expanding issues in pharmacological colloid science. The most used vesicular carriers are liposomes prepared from a wide variety of natural and synthetic phospholipids, but several ionic and non-ionic amphiphiles have been used to form multilamellar and/or unilamellar vesicles. In the present study the synthesis of α,ω-trioxyethylene-bis(sodium 2-dodecyloxy-propylenesulfonate), an anionic Gemini surfactant, and its ability to form niosomes are elucidated. The compound forms vesicles with and without added cholesterol. The vesicular systems were characterized by size, shape and drug entrapment efficiency. The compounds to be incorporated are β-carotene and ferulic acid, as antioxidants, acetyl salicylic acid, as FANS, and the antineoplastic 5-flurouracil, widely used in dermatological disorders. The results of this study show that α,ω-trioxyethylene-bis(sodium 2-dodecyloxy-propylenesulfonate) can be used for the preparation of niosomes entrapping lypophilic, amphiphilic or hydrophilic substances. These niosomes may be promising candidates as percutaneous carriers for the aforementioned drugs. [Copyright &y& Elsevier]

Abstract: Niosomes have shown promise as cheap and chemically stable drug delivery systems. In this paper a novel crown ether amphiphile, 1,16-hexadecanoyl-bis-(2-aminomethyl)-18-crown-6 (Bola A-16), has been synthesized with the aim of developing a long time stable controlled release system. Niosomes have been prepared with different molar ratios of amphiphile and cholesterol and their morphological properties have been determined by quasi-elastic light scattering and transmission electron microscopy. The composition of niosomes affects the entrapment efficiency and the release rate of 5-fluorouracil, a well-known antineoplastic molecule. In addition, other two known azacrown ether amphiphiles (4,7,10,13-pentaoxa-16-aza-cyclooctadecane)-hexadecanedioc acid diamide (Bola D-16) and α,ω-(4,7,10,13-pentaoxa-16-aza-cyclooctadecane)-hexadecane (Bola C-16), have been synthesized and the obtained vesicles have been characterized for comparison. Furthermore, the release profile of 5-fluorouracil in vitro, from these niosomes, has been studied over a period of 6h in order to simulate a hematic adsorption. [Copyright &y& Elsevier]

Abstract: Carotenoids exhibit preventive effects against major diseases, including cancer and atherosclerosis. However, experimental studies on carotenoid functions in cultured cells are limited by the absence of an adequate method of solubilizing carotenoids, since they are unstable when exposed to light or oxygen and highly hydrophobic. In this study, we developed a niosomal formulation, consisting of non-ionic surfactants and cholesterol, which both solubilized and stabilized β-carotene and that allowed to deliver it to cultured cells at concentrations spanning the range of physiological levels. β-Carotene contained in niosomes was highly resistant to sunlight, high temperatures and oxidative stress induced by different sources of free radicals. The carotenoid was extremely stable in culture medium up to 96h. Moreover, it was easily taken up by both immortalized and transformed cells at carotenoid concentrations which ranged from 0.1 to 2μM. Therefore, niosomes provide a convenient, nontoxic and inexpensive vehicle for β-carotene in cell culture. [Copyright &y& Elsevier]

Abstract: Vesicular formulations (liposomes and niosomes) play an increasingly important role since they can be used as drug delivery and targeting systems. We described the formation of two niosomal systems based on synthetic bolaform surfactants (4,7,10,13-pentaoxa-16-aza-cyclooctadecane)-hexadecanedioc acid diamide (BD-16) and α,ω-(4,7,10,13-pentaoxa-16-aza-cyclooctadecane)-hexadecane (BC-16). Systems containing BD-16 or BC-16 and different amount of cholesterol (CH) were prepared by aqueous dispersion of films, followed by examination of methylene blue (MB) entrapment, particle size and morphology. Indeed, we also studied the hydration in the distilled water and physiological solution, in order to investigate the complexing ability on vesicle formation. The results obtained in this study show a high encapsulation capacity and this ability and the size depends on cholesterol content. [Copyright &y& Elsevier]

1,4-Dihydropyridines (DHPs) are the most important class of L-type calcium channel blockers that are employed for the treatment of cardiovascular diseases, particularly hypertension. Various modifications on this scaffold lead to the discovery of new DHPs blocking different types of calcium channels. Among them, the T-type calcium channel has recently attracted great interest due to its role in chronic pain conditions. In this study, we selected three newly synthesized DHPs (HM8, HM10 and MD20) with different selectivity profiles to the T-type calcium channel and formulated them in micellar solutions and micellar-in-gel matrices to be tested for potential topical use in the treatment of neuropathic pain. To prevent the well-known sensitivity to light of the DHPs, the studied compounds were entrapped in colloidal aggregates obtained by using edible Pluronic® surfactants and adding α-tocopherol as an antioxidant. All the prepared formulations were exposed to stressing light, according to international rules. Along with the degradation experiments, the concentrations of the parent compounds and by-products were calculated by multivariate curve resolution—alternating least squares (MCR-ALS) applied to the spectral data. The defined formulations proved suitable as light-stable matrices for the DHP compounds, showing an increase in stability for HM8 and MD20 and an almost complete photoprotection for HM10, compared to ethanol solutions and standard gel formulations. [ABSTRACT FROM AUTHOR]

In this study, liposomes coated with novel multifunctional polymers were proposed as an innovative platform for tumor targeted drug delivery. Novel Folic acid–Cysteine-Thiolated chitosan (FTC) derivatives possessing active targeting ability and redox responsivity were synthesized, characterized, and employed to develop FTC-coated liposomes. Liposomes were characterized for size, surface charge and drug encapsulation efficiency before and after coating. The formation of a coating layer on liposomal surface was confirmed by the slight increase in particle size and by zeta-potential changes. FTC-coated liposomes showed a redox-dependent drug release profile: good stability at physiological conditions and rapid release of liposome-entrapped calcein in presence of glutathione. Moreover, the uptake and cytotoxic activity of doxorubicin-loaded FTC-coated liposomes was evaluated on murine B16-F10 and human SKMEL2 melanoma cancer cells. Results demonstrated enhanced uptake and antitumor efficacy of FTC-coated liposomes compared to control chitosan-coated liposomes in both cancer lines, which is attributed to higher cellular uptake via folate receptor-mediated endocytosis and to triggered drug release by the reductive microenvironment of tumor cells. The proposed novel liposomes show great potential as nanocarriers for targeted therapy of cancer. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Different Acyclovir colloidal system based on Brij 97 were prepared and characterized. • Acyclovir percutaneous permeations have been compared with Zovirax® 5%. • All formulations have improved the Acyclovir skin permeation and deposition. • Better results have been obtained with these systems despite drug concentrations lower than Zovirax® 5%. Abstract The low efficacy of Acyclovir topical therapy is due to its physicochemical properties that limit the permeation across the stratum corneum. The goal of this research was to evaluate the ability of biodegradable surfactant, Brij97, to self-assembly in different types of colloid systems which can improve the Acyclovir permeation and accumulation at the target site (the basal epidermis). New Acyclovir formulation based on Brij97 have been analyzed in order to investigate the effect of drug encapsulation on the structure. After that, the in vitro percutaneous permeation of Acyclovir has been compared with that one of the commercial specialty Zovirax® 5%. To estimate the potential of the new formulations proposed as topical delivery, it has been essential to quantify the Acyclovir in the skin layers. The results confirmed that the self-assembly of the surfactant in different nanosized structures improved the amount of permeated Acyclovir and the formation of intracutaneous drug reservoir. Furthermore, the different lipophilicity and structural organization of carriers based on Brij97 showed different influence on the promotion of permeation. The experimental data suggest that the designed carriers could be a valid alternative to improve the efficacy of the current antiviral therapy. [ABSTRACT FROM AUTHOR]

Hypothesis Due to the well-know surfactant-like properties of diclofenac sodium (DS), vesicular systems consisting exclusively of DS, named diclosomes , were designed with the aim to minimize or avoid the use of other excipients and to improve the formulation biocompatibility. Experiments Diclosomes were designed and characterized in terms of dimensions, polydispersity index, ξ-potential, drug retained, stability as a function of storage time and ex-vivo percutaneous permeation profiles. Additionally, diclosomes were incorporated into gel dosage forms and their performance in terms of permeation enhancement were evaluated. Findings DS was found to form nanosized vesicular systems, both alone and in presence of cholesterol. Increasing hydrophobicity (due to the presence of cholesterol) resulted in smaller vesicles, always spherical and homogeneous in shape. Permeation of DS from free solution was found to be lower respect to ones obtained for all diclosomal formulations, allowing these aggregates to be considered as percutaneous permeation enhancers. DS permeated from diclosomal gels was higher than that obtained with traditional niosomal gel, DS plain gel and commercial specialty Voltaren Emulgel ® 1%, while containing a considerably lower drug amount. [ABSTRACT FROM AUTHOR]

Little is currently known about the genetic relationships between the cultivated olive and wild olive trees in Italy. This report is the first study that has developed molecular characterization of wild olive plants from leaf tissue, without the DNA extraction step. The new protocol was able to amplify every microsatellite tested also in five monovarietal virgin olive oil samples, revealing clear, accurate, reproducible and easily interpretable allelic profiles. Our results show a genetic variability among Sardinia and Calabria wild olive trees, as well as between wild olive and olive varieties sampled from both areas. The possibility to provide a market product with a genetic fingerprint is undoubtedly an added value, especially when considering the high level of food counterfeits spread all-over the world. These results are also in line with the latest rules issued by the European Union aimed to protect niche products. [ABSTRACT FROM AUTHOR]

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

[Display omitted] • We used AG, a bioactive compound extracted from Licorice root, as surfactant. • We have shown the AG ability to self-assemble in homogeneous and stable vesicular structures. • AG niosomes obtained, showed an important antinflammatory activity. • AG niosomes were investigate as carrier of other compounds such as curcumin. In this paper, the surfactant properties of Ammonium Glycyrrhizate, a bioactive compound present in Licorice root were studied. Considering the ability of this bioactive molecule to form micelles, we investigated for the first time the self-assemble of Ammonium Glycyrrhizate in vesicle structures. The organization of Ammonium Glycyrrhizate in vesicles allows to increase its bioavailability and, so, efficacy but also to use them as carrier of other drugs for potential combination therapy. Niosomes made up of Ammonium Glycyrrhizate were prepared using thin layer evaporation technique without the use of additional excipients and characterized in term of size, polydispersion index, Zeta potential and colloidal stability. Moreover, the performance of these innovative vesicles as carriers of hydrophilic drug (Fluorescein sodium) or a lipophilic molecule (Curcumin), was evaluated. Nanocarriers showed nanometric sizes, hexagonal shape, high colloidal stability and ability to encapsulate both hydrophilic and hydrophobic molecules. These vesicles did not showed cytotoxicity nor antimicrobial activityMoreover, it was found that these niosomes enhanced skin permeation and diffusion in several media and an important ability to interact with mucin. Considering its antinflammatory nature, in vitro inhibition of albumin denaturation assay was also carried out to test if the drug maintains these properties also when organized in colloidal structures. The obtained results highlighted an important antinflammatory activity suggesting the potential role of these nanodevices alone or loaded with other therapeutic molecules for the treatment of inflammatory-based diseases. [ABSTRACT FROM AUTHOR]

Abstract: The development of advanced biomaterials and drug-delivery systems has had a significant impact on our ability to treat several diseases. A new study was performed on niosomal formulations obtained from a mixture of commercial surfactants (Tween 80 and Span 80) to be applied topically for the release of Capsaicin. Capsaicin is the pungent principle of red pepper and it has a variety of pharmacological actions on the cardiovascular, respiratory and nervous systems. Niosomal carriers were prepared using a particular ratio between surfactants, to obtain systems with a specific HLB (10,12,14) and characterized in terms of dimension, morphology and their drug entrapment efficiency. Niosomes were compared to microemulsions prepared from the same surfactants in the same ratio, to evaluate their possible use in transdermal drug delivery. As regards the in vitro percutaneous permeation of Capsaicin from both microemulsions and niosomal formulations, it was carried out using diffusion Franz cells. The results indicate that niosomes could better promote the transdermal delivery of Capsaicin, with respect to microemulsions, even if both carriers could be an effective vehicle for topical delivery of this drug. [Copyright &y& Elsevier]

Abstract: UVA exposure induces DNA damage that could result in skin carcinogenesis. Antioxidants are usually employed as protective agents to avoid this problem: in particular, both β-carotene and α-tocopherol can protect the skin against UVA-induced damage. It is well known that the photochemical instability of these compounds has been a limiting factor for their applications to protect skin. In this study, stearyl ferulate-based solid lipid nanoparticles (SF-SLNs), as vehicles for β-carotene and α-tocopherol, were formulated to improve the stability of these compounds. The SF-SLNs were characterized for entrapment efficiency, size and shape together with their cytotoxicity and capability to inhibit lipid peroxidation. After treatment with a pro-oxidant and/or exposition to sunlight the antioxidants entrapped in SF-SLNs were extremely stable. The results highlighted how SF-SLNs represent a suitable vehicle for β-carotene and α-tocopherol stabilizing and protecting them from degradation. A dermatological formulation in order to prevent skin damages is, therefore, suggested. [Copyright &y& Elsevier]

Abstract: Long-term exposure of the skin to UV light causes degenerative effects, which can be minimized by using antioxidant formulations. The major challenge in this regard is that a significant amount of antioxidant should reach at the site for effective photoprotection. However, barrier properties of the skin limit their use. In the present study, vitamin E (α-tocopherol) was loaded into a dextran hydrogel containing ferulic moieties, covalently linked, to improve its topical delivery, and also to increase its relative poor stability, which is due to direct exposure to UV light. Methacrylic groups were first introduced onto the dextran polymer backbones, then the obtained methacrylated dextran was copolymerized with aminoethyl methacrylate, and subsequently esterificated with trans-ferulic acid. The new biopolymer was characterized by Fourier transform infrared spectroscopy. The values of content of phenolic groups were determined. Its ability in inhibiting lipid peroxidation in rat liver microsomal membranes induced in vitro by a source of free radicals, that is tert-butyl hydroperoxide, was studied. Hydrogel was also characterized for swelling behaviour, vitamin E loading efficiency, release, and deposition on the rabbit skin. Additionally, vitamin E deposition was compared through hydrogels, respectively, containing and not containing trans-ferulic acid. The results showed that ferulate hydrogel was a more effective carrier in protecting vitamin E from photodegradation than hydrogel without antioxidant moieties. Then antioxidant hydrogel could be of potential use for cosmetic and pharmaceutical purposes as carrier of vitamin E that is an antioxidant that reduces erythema, photoaging, photocarcinogenesis, edema, and skin hypersensitivity associated with exposure to ultraviolet B (UVB) radiation, because of its protective effects. [Copyright &y& Elsevier]

Abstract: An innovative niosomal system made up of α,ω-hexadecyl-bis-(1-aza-18-crown-6) (Bola), Span 80® and cholesterol (2:5:2 molar ratio) was proposed as a topical delivery system for 5-fluorouracil (5-FU), largely used in the treatment of different forms of skin cancers. Bola-niosomes showed a mean size of ∼400nm, which were reduced to ∼200nm by a sonication procedure with a polydispersion index value of 0.1. Bola-niosomes showed a loading capacity of ∼40% with respect to the amount of 5-FU added during the preparation. 5-FU-loaded bola-niosomes were tested on SKMEL-28 (human melanoma) and HaCaT (non-melanoma skin cancer with a specific mutations in the p53 tumor suppressor gene) to assess the cytotoxic activity with respect to the free drug. 5-FU-loaded bola-niosomes showed an improvement of the cytotoxic effect with respect to the free drug. Confocal laser scanning microscopy studies were carried out to evaluate both the extent and the time-dependent bola-niosome–cell interaction. The percutaneous permeation of 5-FU-loaded niosomes was evaluated by using human stratum corneum and epidermis membranes. Bola-niosomes provided an increase of the drug penetration of 8- and 4-folds with respect to a drug aqueous solution and to a mixture of empty bola-niosomes with a drug aqueous solution. [Copyright &y& Elsevier]

Reverse-mode operation films can be achieved with polymer dispersed liquid crystals by many methods. One method consists in the use of either rough or polyimide treated supports in order to induce homeotropic alignment of the initial mixture that will separate in liquid crystal and polymer rich phases. The major disadvantage is the need for mesogenic monomers to keep a good alignment of the liquid crystal after the polymerization process. In this paper we present results concerning the use of an anisometric, non-mesogenic, tailor-made monomer for the preparation of excellent reverse-mode polymer dispersed liquid crystal shutters cast on rough surfaces. The combined use of rough surfaces and non-mesogenic monomers allows us to exceed earlier limits in physical and chemical properties, cost, and device dimensions by the use of a wider class of monomer molecules. [ABSTRACT FROM AUTHOR]

Nanoantioxidants have emerged as smart devices able to provide improved stability and biocompatibility and sustained and targeted release of conventional antioxidants. In the current research, a new family of nanoantioxidants has been developed by covalently grafting gallic (GA), caffeic (CF) and ferulic (FR) acid on the surfaces of Tween 80 niosomes. First, empty and curcumin (CUR)-loaded vesicles were prepared using a thin-layer evaporation technique and then functionalized with phenolic acids using carbodiimide chemistry. Nanoantioxidants obtained were characterized in terms of size, polydispersity index, zeta potential, and loading efficiency. Their antioxidant activity was studied by ABTS and DPPH assays. Surface functionalization of empty and CUR-loaded vesicles provided stable vesicles with intrinsic antioxidant properties. In vitro antioxidant assays highlighted that vesicles functionalized with FR or GA exhibited better antioxidant activity compared to CF-grafted niosomes. Furthermore, vesicles loaded with CUR and functionalized with GA and CF showed an enhanced scavenging ability of ABTS and DPPH radicals, compared to the single antioxidant-loaded formulations, highlighting an important synergic effect of CUR when used in combination with GA ad CF. [ABSTRACT FROM AUTHOR]

Photostability studies were performed on topical formulations containing the anti-inflammatory drug Nabumetone and an analog newly synthesized in order to achieve better photostability and pharmacokinetic profile. Stability tests, according to the International Conference on Harmonization rules, were applied on ethanol solutions and topical gel formulations of both compounds. The photodegradation profiles were monitored by Multivariate curve resolution applied to the UV spectral data. The inclusion of the compounds in microemulsion was investigated to improve light stability and, at the same time, to ensure a sustained release system for skin delivery. All the formulations in solution, gel, microemulsion, and microemulsion-in-gel were exposed to a forced irradiation of 350 W/m2, corresponding to a 21 kJ/m2 min, for up to 300 min. Photostability increased significantly for both drugs in the liquid microemulsion and microemulsion-in-gel, compared to the ethanol solution and plain gel, reaching a residual drug of 97% and 98% for Nabumetone and analog in microemulsion-in-gel, respectively. Permeation experiments on the microemulsion-in-gel showed a better performance of the analog formulated at 0.2%, compared to the same formulation of Nabumetone at 0.7%. These results highlight the potential of the designed matrices as delayed drug delivery systems along with the use of lower drug doses leading to reduced side effects. [ABSTRACT FROM AUTHOR]

Thermo-sensitive vesicles are a promising tool for triggering the release of drugs to solid tumours when used in combination with mild hyperthermia. Responsivity to temperature makes them intelligent nanodevices able to provide a site-specific chemotherapy. Following a brief introduction concerning hyperthermia and its advantageous combination with vesicular systems, recent investigations on thermo-sensitive vesicles useful for controlled drug delivery in cancer treatment are reported in this review. In particular, the influence of bilayer composition on the in vitro and in vivo behaviour of thermo-sensitive formulations currently under investigation have been extensively explored. [ABSTRACT FROM AUTHOR]

Inclusion of lipids or polymers with a transition temperature closer to physiological body temperature (40–42 °C) is a strategy used in tumor therapy for more than 30 years, because it allows induction of drug release from delivery systems by mild hyperthermia. Unfortunately, most of these thermo-sensitive carriers are removed from circulation before completion of their function. Thus, novel multi-functional niosomes possessing spontaneous stealth and thermo-sensitive properties were developed from L64 Pluronic ® and L64ox as its derivative, in presence or absence of cholesterol. The use of L64 both as amphiphilic constituent and thermo-sensitive molecule, gave the possibility to bypass the use of additional excipients and increased the system biocompatibility. Niosomes diameter ranged from 400 to 750 nm and were long term stable. Calcein and 5-FU possess great affinity to niosomal matrices rich in PEO groups. Negative Z-potential values were attributed to the negative charges onto the niosomes surface and generally change according to the temperature. The in vitro drugs release studies were performed at 25 °C, 37 °C and 42 °C, that are representative of certain conditions (storage, physiological condition and mild hyperthermia, respectively). Results showed that L64-based niosomes possess spontaneous thermo-sensitive properties: drugs releases were found to be more pronounced at 42 °C. These early results are a promising first step for the development of multi-functional devices that combine several advantages such as stealth properties and temperature controllability at the desired location and time, for a more specific and efficient pharmacological therapy. [ABSTRACT FROM AUTHOR]

The loading of chemotherapics into smart nanocarriers that simultaneously possess more than one useful property for specifically targeting a tumor site improves their therapeutic effectiveness, reducing their side effects. Hence, we proposed a combined approach for the treatment of human breast cancer (BC) consisting of the co-encapsulation of doxorubicin and curcumin or doxorubicin and quercetin into multifunctional niosomes, which results in prolonged blood circulation and an ability to spontaneously accumulate at the tumor site (passive target) and to recognize and bind the tumor cells through dual ligand-receptor interactions (active target). The drug-loaded vesicles showed high stability and good capability of loading doxorubicin and antioxidants alone or in combination. Their diameter was around 400 nm. The drugs released from the vesicles were found to be controlled and sustained for over 24 h, with a strong dependence on the co-presence of the loaded molecules. Transferrin and/or folic acid were conjugated on the external surface of the niosomes as ligands, considerably improving the cellular uptake into MCF-7 and MDA-MB-231 malignant cells when compared with the uptake of nonconjugated samples. In vitro evaluation of anticancer activity demonstrated the strong potential of niosomes loaded with a doxorubicin/curcumin combination as useful devices in breast tumor treatment. These features hold great promise for the development of multifunctional devices that combine several advantages such as biocompatibility, stealth properties, loading capability, and active targeting, moving toward the development of more specific and efficient carriers for personalized tumoral therapy. [ABSTRACT FROM AUTHOR]

Cromolyn sodium, or disodium cromoglycate (CS), is a surface active drug : a pharmacologically active compound with an amphiphilic nature. At certain conditions it is able to self-associate in several kind of supramolecular aggregates. Since CS could play the role of both carrier and drug, bypassing the use of additional excipients and increasing the system biocompatibility, the effects of cromolyn self-aggregates on diffusion and percutaneous permeation across rabbit ear skin were investigated. Niosomes (vesicular systems, 0.5 wt% of CS), monomeric and isotropic solutions (0.5 and 5 wt% of CS), nematic (15 wt% of CS) and hexagonal phases (30 wt% of CS) were selected as supramolecular systems and tested as transdermal delivery systems. Results demonstrated that CS was able to form vesicular structures of about 500 nm of diameter and this formulation gave the higher percutaneous permeation profile (systemic action), while isotropic solution and liquid crystals mesophases acted as slower release reservoir of drug on the skin surface (local action), as confirmed by diffusion coefficients. Diffusion rates through a synthetic membrane were dependent both on CS concentration present into the formulations and on its structural organization: maximum diffusion was noticed with isotropic solution, a lower amount of diffused cromolyn sodium was achieved by hexagonal phase. Consequently, CS appears as a versatile surfadrug as, depending on the disease degree, it is possible to modulate its permeation profile by choosing the most appropriate formulation. [ABSTRACT FROM AUTHOR]

Photostability studies were performed on topical formulations containing diclofenac (DC). Niosomal gels were designed as photostabilization systems and ascorbic acid was also added to the new topical formulations because of its antioxidant property. Photodegradation tests were applied on commercial formulations containing DC and novel prepared gels, according to the ICH rules. The experiments were monitored by spectrophotometry and the data processed by multivariate curve resolution analysis to estimate the spectra and concentration profiles of evolved components. Characterization of niosomes was evaluated by size and distribution measurement, morphological analysis and encapsulation efficiency. Permeation experiments were performed across rabbit ear skin up to 24 h. Photodegradation rate of DC was found very fast in commercial formulation, with a residual content of 90% after only 4.38 min under a radiant exposure of 450 W/m 2 . Photostability resulted increased significantly when the drug was entrapped in niosomal systems. The best results were obtained by reaching a 10% degradation after 50.00 min of light exposure after incorporation of DC in niosomes in presence of 5% ascorbic acid. Moreover, niosomal gel also influenced the permeation capability of DC by enhancing the transdermal delivery of the drug. The cumulative dose permeated of DC from niosomal gel was about three times that obtained with the commercial gel. [ABSTRACT FROM AUTHOR]

In this work, nanocrystal formulations, containing two different diclofenac acid crystal forms, were developed with the aim to improve dermal drug bioavailability. Nanosuspensions were obtaining using wet media milling technique and were characterized in terms of size distribution, morphology, zeta potential, differential scanning calorimetry and X-ray powder diffractometry. The ability of the nanocrystals to improve dermal drug bioavailability was investigated in vitro using Franz diffusion vertical cells and newborn pig skin, in comparison with diclofenac acid coarse suspensions and a commercial topical formulation containing diclofenac sodium. Nanocrystals exhibited a mean diameter ranging between 279 and 315 nm and a PI lower than 0.25, as shown by PCS measurements. The XRDP and DSC analysis clearly indicated that the preparation process did not modify the diclofenac polymorphic forms. In vitro transdermal delivery experiments showed an improved skin deposition and permeation of the nanocrystals compared to coarse suspensions and diclofenac sodium commercial topical formulation. These results highlight the fundamental role of the crystal size on drug solubility and, thus, on the ability of a poorly soluble drug to cross the skin and accumulate in the deeper skin layers. [ABSTRACT FROM AUTHOR]

Highlights: [•] Niosomes from glucuronic acid-based surfactant containing doxorubicin or 5FU were prepared. [•] Vesicles were found to encapsulate and release in a prolonged manner both doxorubicin and 5FU. [•] Low toxicity was observed, performing hemolytic tests. [ABSTRACT FROM AUTHOR]

Highlights: [•] The drugs percutaneous permeation profiles from LC-niosomes formulations as multicomponent systems were investigated. [•] Drugs as third component in the formulations could influence the microstructure of the multicomponent system. [•] Drugs percutaneous permeation from LC-niosomes systems, corresponding niosomal and LC binary systems were compared. [•] All the formulation affected in different way the drugs permeation across the skin. [Copyright &y& Elsevier]

Abstract: In chemotherapy the magnetic drug targeting to a specific organ or tissue is proposed on the assumption that magnetic fields are harmless to biological systems. In this light we have vehiculated doxorubicin as model drug by novel magneto-niosomes in order to evaluate the physico–chemical properties of the obtained formulations and the in vitro release profile. Tween 60 and Pluronic L64 have been used as surfactants and the formulation cytotoxicity has been performed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolum bromide and trypan blue dye esclusion tests. Results show that niosome dimensions and doxorubicin entrapment efficiencies are influenced by bilayer composition. In addition, formulations are able to control the deliver and release of the drug active form in a retarded manner. No additional toxicity, due to the encapsulation of ferrofluid into niosomes core, has been detected. [Copyright &y& Elsevier]

Abstract: The aim of this work is to design, prepare and characterize l-lysine based prodrugs capable of targeting 6-mercaptopurine to the colon, an anti-tumor and immunosuppressant drug, and 5-aminosalicylic acid (5-ASA), drug of choice for inflammatory bowel disease (IBD). More specifically, Nɛ-feruloyl-S-(6-purinyl)-l-lysine and Nɛ-acryloyl-S-(6-purinyl)-l-lysine were synthesized and then characterized by FT-IR, 1H-NMR and GC/MS spectroscopies. The ability of feruloyl derivative in inhibiting lipid peroxidation in rat liver microsomal membranes, induced in vitro by tert-butyl hydroperoxide as source of free radicals, was evaluated. Moreover, Nɛ-acryloyl-S-(6-purinyl)-l-lysine, polymerizable prodrug, was used to microspheres realization for 5-ASA release. These lasts, obtained by emulsion inverse technique, were characterized by light scattering and scanning electron microscopy (SEM) analysis. The microspheres equilibrium swelling degree was evaluated and showed good swelling behaviour in simulating colonic fluids. Results confirm the possibility that the application range of l-lysine prodrug can be extended to the treatment of intestinal diseases whose conventional therapy envisages medications with serious side effects that, thanks to this new strategy, can be minimized in an optimal way. [Copyright &y& Elsevier]

Abstract: The interactions between bovine serum albumin and cationic gemini surfactants were investigated as a function of concentration, under different pH conditions. The investigation deals with dielectric relaxation, dynamic light scattering, ζ-potential, circular dichroism, and UV spectroscopy. The interactive behavior of the anionic form is quite different from the cationic species. It indicates that protein–surfactant interactions are mostly electrostatic in nature and depend on the state of charge of bovine serum albumin. The results indicate the presence of both hydrophobic and electrostatic contributions in the interactions of gemini with bovine serum albumin. Comparison of dynamic light scattering, dielectric relaxation, electrophoretic mobility, and optical circular dichroism allows drawing some preliminary hypotheses on the different contributions to surfactant binding and supports former studies on the formation of complexes between the bovine serum albumin and the above species. [Copyright &y& Elsevier]

Abstract: In the present work, we report the synthesis of cellulose hydrogel containing ferulic moieties and the evaluation of its antioxidant and scavenger activity. Acrylic groups were inserted onto cellulose backbone by a heterogeneous synthesis to produce two cellulose monomers with different degree of substitution (DS). The radical copolymerization of acrylcellulose (AcrC) with N,N-dimethylacrylamide (DMAA) was carried out in NH3/Urea aqueous solution, in a range of composition between 24 and 60wt% of AcrC. The obtained hydrogels were characterized by infrared spectroscopy (FT-IR). Their equilibrium swelling degree (α%) was evaluated. They showed good swelling behavior in simulating gastric, intracellular and intestinal fluids and no more different at various pH. The ferulic moieties were directly grafted on the free hydroxylic groups of cellulose hydrogel by acylation, using dicyclohexylcarbodiimide (DCC) and 4-hydroxybenzotriazole (HBT) as condensation agents. Finally, the antioxidant activity in inhibiting the lipid peroxidation, in rat-liver microsomal membranes, induced in vitro by two different sources of free radicals, 2,2′-azobis (2-amidinopropane) (AAPH) and tert-butyl hydroperoxide (tert-BOOH), was evaluated. The effects of scavenging DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals were also investigated. Hydrogel was found to be very efficient scavengers of DPPH radicals. The results strongly suggested that the antioxidant hydrogel neutralize free radicals. This biomaterial could be successfully applied in pharmaceutical field both as prodrug of trans-ferulic acid than as carrier for photo and thermo-degradable drugs to improve their stability. [Copyright &y& Elsevier]

Abstract: pH-Sensitive bovine serum albumin (BSA) hydrophilic microspheres were prepared by free radical polymerization of methacrylate derivatized BSA and methacrylic acid sodium salt. Incorporation of both monomers in hydrogels was confirmed by Fourier transform infrared spectroscopy. Morphological analysis by scanning electron microscopy showed spherical shape and porous surface of all prepared samples. The microspheres showed high water affinity at neutral pH values and a narrow dimensional distribution. Network density of hydrogels depends on derivatization degree (DD%) of BSA and/or concentration of modified BSA in the polymerization feed. In order to employ the prepared samples such as pH-sensitive hydrogels, in vitro release studies, in media simulating biological fluids, were performed using diflunisal (DF) and β-propranolol (PR) as model drugs. Experimental data showed that the release profiles depend on drug–matrix interactions and diffusional limitation awardable to crosslinking degree of microparticles. β-Propranolol is quickly released at pH 1.0 and a complete release after 1h at pH 6.8 was observed. In the case of diflunisal pH-sensitive release was observed. At pH 1.0 low amounts of drug were released (w/w<10% after 2h). When the pH is 6.8, the diflunisal release increased in the amount (w/w>75% after 24h). [Copyright &y& Elsevier]

Abstract: Sudan I is a synthetic azoic dye employed as an additive in foods, and in particularly in those containing chilli powders, because of his intense red–orange colour. Now European Community does not allow “Sudan I” as an additive in foods because of its demonstrated cancerogenity. Several methods were developed to detect the presence of this compound (HPLC, GC/MS). However when “Sudan I” is mixed just in traces in foods, very expensive instruments are necessary (LC/MS/MS) to reveal it. This study describes the synthesis of a molecularly imprinted polymers (MIPs) for solid phase extraction (MISPE) using Sudan I as template. This procedure allows to concentrate this compound in order to make it detectable by HPLC. Furthermore we investigated the ability of these MISPE cartridges to absorb selectively Sudan I from food matrices. Considerable differences in the interaction with “Sudan I” were observed when MIPs were used as stationary phase in SPE compared with the non imprinted polymers (NIPs). [Copyright &y& Elsevier]

Chemotherapy is a vital option for cancer treatment; however, its therapeutic outcomes are limited by dose-dependent toxicity and the occurrence of chemoresistance. siRNAs have emerged as an attractive therapeutic option enabling specific interference with target genes. Combination therapy using chemotherapeutic agents along with gene therapy could be a potential strategy for cancer management, which not only improves therapeutic efficacy but also decreases untoward effects from dose reduction. In this study, a cationic niosome containing plier-like cationic lipid B was used to convey siRNA against anti-apoptotic mRNA into MCF-7 and MDA-MB-231 cells. Mcl-1 silencing markedly decreased the viability of MCF-7 cells and triggered apoptosis. Moreover, computer modeling suggested that the combination of doxorubicin (Dox) and Mcl-1 siRNA exhibited a synergistic relationship and enabled a dose reduction of each agent at 1.71 and 3.91 folds, respectively, to reach a 90% inhibitory effect when compared to single-agent treatments. Synergistic antitumor activity was further verified in a 3D spheroid culture which revealed, in contrast to single-agent treatment, the combination markedly decreased spheroid volume over time. Together, the combination therapy between Mcl-1 silencing and Dox exhibits a synergistic effect that may be exploited for novel breast cancer treatment. [ABSTRACT FROM AUTHOR]

Simvastatin (SIM) is a HMG-CoA reductase inhibitor employed in the management of hyperlipidemia. However, its low bioavailability limits its clinical efficacy. The objective of this study was to overcome the poor bioavailability of SIM via the transdermal application of a SIM-loaded niosomal gel. Niosomes loaded with SIM were fabricated by means of the thin-film hydration method and optimized through a 33-factorial design utilizing Design Expert® software. The prepared niosomes were evaluated for entrapment efficiency (EE%), zeta potential, vesicle size, and cumulative percentage of drug release. The optimum niosomal formulation was loaded on the gel and evaluated for physical properties such as color, clarity, and homogeneity. It was also evaluated for spreadability, and the cumulative % drug release. The best niosomal gel formula was appraised for ex vivo permeation as well as pharmacokinetic study. The SIM-loaded niosomes showed EE% between 66.7–91.4%, vesicle size between 191.1–521.6 nm, and zeta potential ranged between −0.81–+35.6 mv. The cumulative percentage of drug released was ranged from 55% to 94% over 12 h. SIM-loaded niosomal gels were clear, homogenous, spreadable, and the pH values were within the range of physiological skin pH. Furthermore, about 73.5% of SIM was released within 24 h, whereas 409.5 µg/cm2 of SIM passed through the skin over 24 h in the ex vivo permeation study. The pharmacokinetic study revealed higher AUC0–∞ and Cmax with topical application of SIM-loaded niosomal gel compared to topical SIM gel or oral SIM suspension. The topical application of SIM-loaded niosomal gel ascertained the potential percutaneous delivery of SIM. [ABSTRACT FROM AUTHOR]

Abstract: We prepared cellulose cotton fibers containing ampicillin moieties and evaluated their antibacterial activity. In spite of recent progress in experimental and clinical medicine, the problem of chronic wounds treatment remains to be solved. In fact conventional methods are based on solutions of antibiotics and antiseptics and ointment bandages but the efficacy of this method is low and so the idea to use modified cotton gauzes would have to prevent infections insorgence during wounds healing. Ampicillin, a large spectrum antibiotic, was covalently coupled to cellulose backbone of hydrophilic cotton fibers by a heterogeneous synthesis to produce a functionalized biopolymer with a satisfactory degree of substitution (DS) and antibacterial activity. The obtained biopolymer was characterized by infrared spectroscopy (FT-IR). Finally, the antibacterial activity in inhibiting microorganism growth in Petri dishes, was evaluated. The results suggested that these biomaterials posses an excellent “in vitro” antibacterial activity and so they can be efficiently employed in biomedical fields for chronic wounds management to ensure a valid protection against infections and contaminations. Biopolymers so functionalized were found to be very efficient to contrast sensible bacteria growth. [Copyright &y& Elsevier]

The clinical efficacy of methotrexate (MTX) is limited by its poor water solubility, its low bioavailability, and the development of resistance in cancer cells. Herein, we developed novel folate redox-responsive chitosan (FTC) nanoparticles for intracellular MTX delivery. l-Cysteine and folic acid molecules were selected to be covalently linked to chitosan in order to confer it redox responsiveness and active targeting of folate receptors (FRs). NPs based on these novel polymers could possess tumor specificity and a controlled drug release due to the overexpression of FRs and high concentration of reductive agents in the microenvironment of cancer cells. Nanoparticles (NPs) were prepared using an ionotropic gelation technique and characterized in terms of size, morphology, and loading capacity. In vitro drug release profiles exhibited a glutathione (GSH) dependence. In the normal physiological environment, NPs maintained good stability, whereas, in a reducing environment similar to tumor cells, the encapsulated MTX was promptly released. The anticancer activity of MTX-loaded FTC-NPs was also studied by incubating HeLa cells with formulations for various time and concentration intervals. A significant reduction in viability was observed in a dose- and time-dependent manner. In particular, FTC-NPs showed a better inhibition effect on HeLa cancer cell proliferation compared to non-target chitosan-based NPs used as control. The selective cellular uptake of FTC-NPs via FRs was evaluated and confirmed by fluorescence microscopy. Overall, the designed NPs provide an attractive strategy and potential platform for efficient intracellular anticancer drug delivery. [ABSTRACT FROM AUTHOR]

An in-depth analysis of nanotechnology applications for the improvement of solubility, distribution, bioavailability and stability of reverse transcriptase inhibitors is reported. Current clinically used nucleoside and non-nucleoside agents, included in combination therapies, were examined in the present survey, as drugs belonging to these classes are the major component of highly active antiretroviral treatments. The inclusion of such agents into supramolecular vesicular systems, such as liposomes, niosomes and lipid solid NPs, overcomes several drawbacks related to the action of these drugs, including drug instability and unfavorable pharmacokinetics. Overall results reported in the literature show that the performances of these drugs could be significantly improved by inclusion into nanosystems. [ABSTRACT FROM AUTHOR]