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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., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The use of nanodevices to transport active compounds like small-molecular drugs, peptides, or genes found an increased attention throughout the different fields of natural sciences. Moreover, recent research trends are focused on the employment of smart nanocarriers able to react on certain internal or external applied stimuli, in order to achieve temporal and site-specific drugs/gene release. In contrast to traditional biodegradable nanocarriers that slowly release drugs inside the cells, these smart nanosystems are able to quickly release or even dump drugs in response to a specific biological signal in the target cancer cells such lower pH, high redox potential or over expression of enzymes or to external stimuli such as temperature, light, ultrasounds and magnetic field. This review gives a brief overview about some types of stimuli-responsive nanocarriers, with the main focus on magnetic fieldresponsive devices obtained from natural polymers. The concept of magnetic field-sensitive nanocarriers, their advantages and disadvantages, the methods of preparation and applications in various fields of drug delivery will be explored, giving an exhaustive collection of the findings of recent investigations.

Nanotechnology encompasses the production and applications of physical, chemical, and biological systems at scales ranging from individual atoms or molecules to around 100 nanometres, as well as the integration of the resulting nanostructures into larger systems. Nanomaterials differ from bulk materials for their relatively larger surface-area-to-mass ratio, consequently they become more chemically reactive and can show different optical, magnetic and electrical behaviours. In recent years, engineered nanomaterials have gained a particular attention in some fields such as environmental protection (soil, air and water remediation/treatment) and medicine (bio-sensing, imaging, and drug delivery). Nanoparticles can be used to monitor in real-time some pollutants (including heavy metal ions, organic compounds, microbiological pathogens, etc.) present even at extremely low concentrations in different environments. The use of nanomaterials for waste remediation/treatment results in a technology more cost-effective and rapid than current conventional approaches thanks to their enhanced surface area, transport properties, and sequestration characteristics. In addition, the integration of molecular biology and medicine with nanotechnology has resulted in new active nanostructures able to interact with biological systems. Nanocarriers based on carbon nanotubes, fumed silica (SiO2), titanium dioxide (TiO2), and magnetite and maghemite (Fe3O4, and γ-Fe2O3) nanoparticles have a distinct advantage over other drug carriers as they can be opportunely designed to reach the desired targets. As a consequence, such nanostructures can represent an important platform for enhanced medical imaging and controlled drug delivery. Here, some applications of nanomaterials as water purifying agents and drug delivery systems are reported.

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., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Niosomes are vesicular systems composed of surfactant molecules, claimed to be used as drug delivery carriers thanks to their physico-chemical and biological properties. The aim of this work was to design niosomes obtained with a surfactant synthesized from glucuronic acid. Doxorubicin and 5FU were used as model drugs. Niosomes were prepared with different ratios between surfactant and cholesterol, and characterized in terms of size, morphology, drugs entrapment efficiency and in vitro releases, to identify the optimal formulation to be used in pharmaceutical fields. In addition, the hemolytic activity of all formulations have been also evaluated. Results showed that dodecylglucuronamide surfactant was able to produce vesicular systems with or without the presence of cholesterol. Niosomes resulted regular in size and shape and they have been found to encapsulate and release in a controlled manner both doxorubicin and 5-fluorouracil. Hemolytic tests showed that the capability of disrupting erythrocyte only depend on the size of colloidal aggregates. Finally, our formulations could be potentially used as antitumoral delivery systems in anticancer therapy., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Niosomal vesicular systems containing resveratrol, alpha-tocopherol and curcumin as single agents and in combination, were designed with the aim to develop novel cosmeceutical formulations. The effects of antioxidants co-encapsulation on the physico-chemical properties of the carriers, their antioxidant properties and in vitro percutaneous permeation profiles were evaluated. Results showed that the co-encapsulation of resveratrol/curcumin and alpha-tocopherol/curcumin affected the physico-chemical properties of niosomes and the entrapment efficiencies values, respect to the formulations containing the single antioxidant. The antioxidants in vitro percutaneous permeations appeared to be controlled and improved respect to the corresponding free solutions used as control. Moreover the antioxidants combinations resulted in a promoted ability to reduce free radicals, due to a synergic antioxidant action., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Recently niosomes have been used as nutraceutical vehicles of functional components, useful in the prevention of many diseases caused by oxidative stress, with the aim to control their delivery into the body and to increase the nutritional quality of food dairy products with which these products can be enriched. We decided to develop novel niosomal formulations containing nutritional supplements such as gallic acid, ascorbic acid, curcumin and quercetin as single agents and in combination, to evaluate the effect of the active molecules co-encapsulation on the physico-chemical properties of the carriers, on their antioxidant properties and capability of releasing the encapsulated materials. Results suggest that the co-encapsulations of gallic acid/curcumin and ascorbic acid/quercetin mix influence their physico-chemical properties and their entrapment efficiencies respect to the formulations containing the single antioxidant; also the antioxidants releases appeared to improve and their combinations resulted in a promoted ability of reducing free radicals, due to a synergic antioxidant action., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The percutaneous permeation profiles of sulfadiazine sodium salt, propranolol hydrochloride and tyrosol from novel liquid crystal-niosomes formulations as multicomponent systems, were investigated. The new carriers were prepared from mixture of water/surfactant, AOT or Pluronic L64 as anionic and nonionic surfactants, respectively, in order to obtain lamellar LLC phases. The same surfactants were used to prepare also the vesicular systems (niosomes) that were added to the corresponding gel. The obtained multicomponent drug carrier was characterized by deuterium nuclear magnetic resonance spectroscopy, in order to understand if the introduction of the drug or drug-loaded niosomal suspension, as third component in the formulations, could influence the microstructure of the system and then the drug delivery across the skin. Simple AOT and L64-based niosomal formulations and LLCs phases were then prepared and used as control. Different drugs percutaneous availability was achieved, and the results revealed that the obtained gel-niosomes carriers were affected by the chemical structure of the drugs and by their affinity for the components. As a consequence these systems could be proposed as novel transdermal drug delivery systems, since they were found able to control the percutaneous permeation of small drugs across the skin., (Copyright © 2013 Elsevier B.V. All rights reserved.)

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]

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]