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Because of its high biocompatibility, bio-degradability, low-cost and easy availability, cellulose finds application in disparate areas of research. Here we focus our attention on the most recent and attractive potential applications of cellulose in the biomedical field. We first describe the chemical/structural composition of cellulose fibers, the cellulose sources/features and cellulose chemical modifications employed to improve its properties. We then move to the description of cellulose potential applications in biomedicine. In this field, cellulose is most considered in recent research in the form of nano-sized particle, i.e., nanofiber cellulose (NFC) or cellulose nanocrystal (CNC). NFC is obtained from cellulose via chemical and mechanical methods. CNC can be obtained from macroscopic or microscopic forms of cellulose following strong acid hydrolysis. NFC and CNC are used for several reasons including the mechanical properties, the extended surface area and the low toxicity. Here we present some potential applications of nano-sized cellulose in the fields of wound healing, bone-cartilage regeneration, dental application and different human diseases including cancer. To witness the close proximity of nano-sized cellulose to the practical biomedical use, examples of recent clinical trials are also reported. Altogether, the described examples strongly support the enormous application potential of nano-sized cellulose in the biomedical field.

Background New drugs to tackle the next pathway or mutation fueling cancer are constantly proposed, but 97% of them are doomed to fail in clinical trials, largely because they are identified by cellular or in silico screens that cannot predict their in vivo effect. Methods We screened an Adeno-Associated Vector secretome library (> 1000 clones) directly in vivo in a mouse model of cancer and validated the therapeutic effect of the first hit, EMID2, in both orthotopic and genetic models of lung and pancreatic cancer. Results EMID2 overexpression inhibited both tumor growth and metastatic dissemination, consistent with prolonged survival of patients with high levels of EMID2 expression in the most aggressive human cancers. Mechanistically, EMID2 inhibited TGFβ maturation and activation of cancer-associated fibroblasts, resulting in more elastic ECM and reduced levels of YAP in the nuclei of cancer cells. Conclusion This is the first in vivo screening, precisely designed to identify proteins able to interfere with cancer cell invasiveness. EMID2 was selected as the most potent protein, in line with the emerging relevance of the tumor extracellular matrix in controlling cancer cell invasiveness and dissemination, which kills most of cancer patients.

The aim of the present work is the characterization of biscuit doughs enriched with pomegranate peel powder (PPP) at 3 (PPP3) and 5 (PPP5) wt% in the prospect of developing a fortified aliment as a support of the therapy of chronic inflammatory diseases of the intestinal tract. The total phenolic content of the powder was preliminarily evaluated. Then, the main compounds present in the PPP were identified by HPLC-ESI-TOF-MS analysis, being mainly hydrolysable tannins. The PPP was then treated at 180 °C for 20 min to mimic the baking treatment, and its water-soluble fraction (PPPwsf) was then added in the Caco-2 cell culture as a model of the intestinal epithelial barrier to verify its dose-dependent toxicity, ability in counteracting the oxidative stress, and anti-inflammatory action. Rheological experiments were performed to predict the macroscopic behavior of the PPP-added doughs during lamination and biscuit baking. SEM investigations gave their contribution to the microscopic comprehension of the dough structure. Finally, a consumer panel composed by thirty volunteers was enrolled to express its opinion on the sensory agreeableness of the biscuits prepared with two different concentrations of PPP compared with the reference dough. The discussion is focused on the biological effects of the main components found in the PPP.

The aim of this work is the evaluation of the addition of Moringa leaf powder (MLP) in cookies in terms of antioxidant properties, dough processability and sensorial properties of the cookies. The total content of biophenols and flavonoids in MLP was detected and the identification of the bioactive molecules was performed by HPLC-ESI-TOF-MS measurements, before and after oven treatment at 180 °C for 20 min. After a preliminary evaluation of the MLP water soluble fraction (MLPsf) cytotoxicity, its protective effect against an oxidative injury induced in the SH-SY5Y cells was assessed. Data evidence that the bioactive molecules present in MLPsf are effective in preventing ROS production and in protecting neuronal cells against oxidative stress. Prototypes of cookies containing MLP in different concentrations were then produced and evaluated by a consumer panel. Selected doughs containing MLP were analysed to determine the total content of biophenols in the cookies after baking and their enrichment in terms of valuable chemical elements. The influence of MLP on the viscoelastic behaviour and morphology of the doughs was also assessed. Finally, the potential role in counteracting the insurgence of not treatable neurodegenerative pathologies of two main MLP components, glucomoringin and kaempferol derivatives, present also after the thermal treatment, was discussed.

In this paper we have concentrated on the characterization of calcium alginate hydrogels loaded with a model drug (myoglobin) by means of a mechanical approach; in addition, release tests of myoglobin from alginate hydrogels were performed. At a fixed temperature, relaxation tests (mechanical study) were carried out on matrices constituted by different polymer concentrations. The interpretation of the relaxation behavior of the different matrices was conducted using the generalized Maxwell model; as a result of this investigation it was possible to conclude that for polymer concentrations greater than 0.5 g/ 100 mL the matrices behaved as solid materials. In addition, it was observed that the mechanical properties of the matrices increased with polymer concentration. With regard to the release tests, the diffusion coefficient of myoglobin in the matrix in relation to polymer concentrations was determined. The mechanical and release data where then analyzed by Flory’s theory and by a modified free-volume theory, respectively, to estimate the network mesh size ξ. The comparison between the mesh sizes obtained by the two approaches showed a satisfactory agreement for polymer concentrations greater than 0.5 g/100 mL. It should be noted that the approach proposed here to determine the polymeric network meshes is absolutely general and can be advantageously applied to the characterization of other similar polymeric systems.

Background: The new concepts of personalized and precision medicine require the design of more and more refined delivery systems. In this frame, hydrogels can play a very important role as they represent the best surrogate of soft living tissues for what concerns rheological properties. Thus, this paper focusses on a global theoretical approach able to describe how hydrogel polymeric networks can affect the release kinetics of drugs characterized by different sizes. The attention is focused on a case study dealing with an interpenetrated hydrogel made up by alginate and poly(N-vinyl-2-pyrrolidone). Methods: Information about polymeric network characteristics (mesh size distribution and polymer volume fraction) is deduced from the theoretical interpretation of the rheological and the low field Nuclear Magnetic Resonance (NMR) characterization of hydrogels. This information is then, embodied in the mass balance equation whose resolution provides the release kinetics. Results: Our simulations indicate the influence of network characteristics on release kinetics. In addition, the reliability of the proposed approach is supported by the comparison of the model outcome with experimental release data. Conclusions: This study underlines the necessity of a global theoretical approach in order to design reliable delivery systems based on hydrogels.

fudustrial uses of polysaccharides centre on their ability to thicken or structure many times their own weight of water, or in other words to control the rheology of hydrated systems. Until comparatively recently, however, objective characterisation of polysaccharide rheology, except in a few specialist research laboratories, was largely confined to compression of gels, simple measurements of solution viscosity, often in ill-defined geometries, and imitative tests intended to reflectproductperformance in specific areas ofend-use. Several factors have combined to bring a wider range of rheological techniques into common use. One is the increasing practical importance of systems that cannot adequately be described as solids or liquids, such as 'weak gels' and spreadable pastes. fu parallel, routine characterisation of such systems has become economically feasible with the development of a new generation of comparatively inexpensive computer-controlled instruments. There has also been a change ofemphasis from phenomenologicaldescription ofproduct texture towards the use of rheological measurements to probe the underlying molecular and supramolecular structures and the processes by which they are formed. As a result, even the most pragmatic producers and users of industrial polysaccharides are probably now familiar with terms such as creep compliance, stress overshoot and the ubiquitous G' and G\", although perhaps not fully understanding their precise meaning or practical significance. A definitive text giving a rigorous description of the rheological approaches relevant to polysaccharide systems is therefore appropriate and timely. Romano Lapasin and Sabrina Priel are to be congratulated for tackling the daunting but worthwhile taskofproducing such avolume.

Polymers and surfactants are essential ingredients of the printing paste. Polysaccharides are used commercially to thicken, suspend or stabilise aqueous systems. Also they are used to produce gels and to act as flocculates, binders, lubricants, to serve as modifiers of film properties, and have a function as adjusters of rheological parameters. Surfactants, on the other hand, perform numerous functions acting as dispersants, wetting agents, emulsifiers and antifoaming agents.The rheological properties of polysaccharide thickeners (guar gums with different substitution levels and different producers) at different concentrations and temperatures and, second, the effects produced by the addition of nonionic surfactants (polyoxyethylene stearyl alcohols with different numbers of EO groups) have been studied under linear and nonlinear shear conditions. Experimental data have been correlated with the different models: flow curves with the Cross, Carreau and Meter-Bird model, and mechanical spectra with the generalized Maxwell model and Friedrich-Braun model. The surface tensions of aqueous systems containing polysaccharide and/or surfactants have been determined over extended concentration ranges in order to detect the CMC conditions and to provide a better understanding about the polysaccharide-surfactant interactions.

Microemulsions are profitably employed in the pharmaceutical field to prepare drug delivery systems release for guest drugs sparingly soluble in water. In particular, they can be used for topical and transdermal administration in place of ointments or creams, on condition that their rheological properties are properly modulated. The present work concerns the analysis of the rheological effects produced by the addition of different amounts of Carbopol 940, a polymer widely used for topical applications, to an O/W microemulsion containing a lipophilic phase (Labrafac Hydro, 21 wt%) and stabilized by the surfactant (Cremophor RH40)/co-surfactant (Transcutol) couple. The contribution of the disperse phase is evaluated by comparing the linear and nonlinear properties of the Carbopol/microemulsion system (CM) with those of the corresponding aqueous Carbopol systems with co-surfactant (CWT) and without co-surfactant (CW). Four polymer concentrations (0.25%, 0.5%, 1%, and 2%) are taken into consideration.The linear viscoelastic properties of the microemulsions essentially mirror those of the corresponding aqueous Carbopol systems when the polymer concentration is sufficiently high (1–2%). In these conditions the oil phase is reasonably hosted within the meshes of the three-dimensional polymeric gel network and gives only a slight contribution to the connectivity of the whole system. Similar considerations can be drawn from the flow behavior of the systems examined in the low shear region.

Purpose: to design, assemble and test a prototype of a novel production plant, suitable for producing microparticles (MPs) by processing highly viscous feed solutions (FSs). Methods: the prototype has been built using a commercial air compressor, a piston pump, an airless spray-gun, a customized air-treatment section, a timer, a rotating base, and a filtration section. Preliminary prototype parameter setting was carried out to individuate the best performing nozzle’s dimension, the nebulization timing, and the CaCl2 concentration in the gelation fluid. In addition, prototype throughput (1 L to 5 L) and the range of practicable feed solution (FS) viscosities were assayed. A set of four batches was prepared in order to characterize the MPs, in terms of mean particle size and distribution, flow properties, swelling, encapsulation efficiency and release. Results: according to a qualitative scoring, the large nozzle was suitable to nebulize FSs at a higher alginate concentration. Conversely, the small nozzle performed better in the processing of FSs with an alginate concentration up to 2% w/v. Only at the highest degree of viscosity, corresponding to 5% w/v of alginate, the FS processing was not technically possible. Among the CaCl2 concentrations considered, 15% w/v was recognized as the most versatile. The prototype appears to be convenient and suitable to grant a high yield starting from 2 L of FS. The flow behavior of the FSs assayed can be satisfactorily described with the Carreau-Yasuda equation and the throughput begins to slightly decrease for FSs at alginate concentrations exceeding 3% w/v. MP morphology was irregular with crumpled shape. The angle of repose indicates a good flowability and the release studies showed gastro-resistance and potential prolonged release applications. Conclusions: the novel prototype of production plant is suitable to process large amounts (2 L or more) of FSs, characterized by a high viscosity, to produce MPs suitable for bioactive principle delivery.