Recycling of textile wastes, by acid hydrolysis, into new cellulosic raw materials.

Chemical recycling can be used to separate fibers that are constituents of different types of fabrics. This type of process can be considered one of the most effective forms of recycling, given that a large part of fabrics is made up of fiber mixtures. As part of an innovative circular strategy, the main goal of this work was to study the conditions for extracting cellulose from mixed textile wastes by acid hydrolysis and further transform it into cellulose derivatives, thus contributing to reduce such wastes and expanding the possible sources of cellulose.

Safety Assessment of Polypyrrole Nanoparticles and Spray-Coated Textiles.

Polypyrrole (PPy) nanoparticles (NPs) are used for the coating of materials, such as textiles, with biomedical applications, including wound care and tissue engineering, but they are also promising antibacterial agents. In this work, PPy NPs were used for the spray-coating of textiles with antimicrobial properties. The functional properties of the materials were verified, and their safety was evaluated.

Trends on the Cellulose-Based Textiles: Raw Materials and Technologies.

There is an emerging environmental awareness and social concern regarding the environmental impact of the textile industry, highlighting the growing need for developing green and sustainable approaches throughout this industry's supply chain. Upstream, due to population growth and the rise in consumption of textile fibers, new sustainable raw materials and processes must be found. Cellulose presents unique structural features, being the most important and available renewable resource for textiles.

Proteins Derived from the Dairy Losses and By-Products as Raw Materials for Non-Food Applications.

The disposal of a high volume of waste-containing proteins is becoming increasingly challenging in a society that is aware of what is happening in the environment. The dairy industry generates several by-products that contain vast amounts of compounds, including proteins that are of industrial importance and for which new uses are being sought. This article provides a comprehensive review of the potential of the valorisation of proteins that can be recovered by chemical and/or physical processes from protein-containing milk by-products or milk surplus, particularly whey proteins or caseins.

Design of a chromogenic substrate for elastase based on split GFP system-Proof of concept for colour switch sensors.

Recent studies have demonstrated that human neutrophil elastase (HNE) can be used as marker for inflammation/infection of chronic wounds since it was found to be present in high concentration in exudate collected from chronic wounds. Biosensors used in wound care benefit from a chromogenic signalling due to the readiness of signal interpretation, but the most common use faint yellow chromogenic molecules such as -nitroaniline (Na). In addition, if to be converted into smart dressings, the colour of the detection system should not be masked by the exudate's colour.

Internalization of Methotrexate Conjugates by Folate Receptor-α.

The folate antagonist methotrexate is a cytotoxic drug used in the treatment of several cancer types. The entry of methotrexate into the cell is mediated by two main transport systems: the reduced folate carrier and membrane-associated folate receptors. These transporters differ considerably in their mechanism of (anti)folate uptake, substrate specificity, and tissue specificity.

Two Engineered OBPs with opposite temperature-dependent affinities towards 1-aminoanthracene.

Engineered odorant-binding proteins (OBPs) display tunable binding affinities triggered by temperature alterations. We designed and produced two engineered proteins based on OBP-I sequence: truncated OBP (tOBP) and OBP::GQ::SP-DS3. The binding affinity of 1-aminoanthracene (1-AMA) to these proteins revealed that tOBP presents higher affinity at 25 °C (kd = 0.

Oil-based cyclo-oligosaccharide nanodevices for drug encapsulation.

New encapsulation nanodevices were synthesized by emulsification of cyclo-oligosaccharides fully substituted by hydrophobic palmitic chains. These highly hydrophobic compounds, acquire oily-like behaviour at moderate temperatures (∼50°C) and when submitted to ultrasound (US) can undergo emulsification. The improved emulsifying properties of modified cyclo-oligosaccharides are suitable to produce small and narrow sized nanoemulsions with ability to encapsulate amphiphilic molecules.

Peptide-protein interactions within human hair keratins.

We selected 1235 decapeptides from human hair proteins encoded by human genes of keratins and keratin associated proteins. The peptides were linked to glass arrays and screened for their affinity towards a solution of human hair extracted keratin fraction. Based on the physicochemical properties of the peptides, ten variables were studied: content of different types of amino acid side chains (cysteine, hydrophobic, polar, basic, acidic, aromatic rings, amide, alcohol side chains), isoelectric point, and net charge.

Permeation of skin with (C) fullerene dispersions.

Dispersions in transcutol/isopropyl myristate make C fullerene molecules suitable for transdermal delivery. We found that C can successfully permeate the skin using pig skin in Franz diffusion cells. Molecular dynamics simulations and transmission electron microscopy confirmed these observations.

In vivo confocal Raman spectroscopy and molecular dynamics analysis of penetration of retinyl acetate into stratum corneum.

Objective: The purpose of this study is to elucidate the behavior of retinyl acetate in penetrating human skin without the presence of enhancers by using confocal Raman spectroscopy and molecular dynamics simulation.

Methods: In this study, in vivo confocal Raman spectroscopy was combined with molecular dynamics simulation to investigate the transdermal permeation of the aqueous suspension of retinyl acetate.

Results: Permeation was measured after 30min, and retinyl acetate was found up to 20μm deep inside the stratum corneum.

Insights on the mechanical behavior of keratin fibrils.

A computational molecular model of a truncated keratin protofibril (8 chains of hair keratin, PDB provided in Supplementary material) was used, to run a series of steered molecular dynamics simulations obtaining strain-stress curves. These results were compared with experimental mechanical data on hair fibers. Our data demonstrate that the molecular dynamics simulations can model hair mechanical properties.

Protein Formulations for Emulsions and Solid-in-Oil Dispersions.

Needs from medical and cosmetic areas have led to the design of novel nanosized emulsions and solid-in-oil dispersions of proteins. Here, we describe the production of those emulsions and dispersions using high-energy methodologies such as high-pressure homogenization or ultrasound. Recent work has resulted in new mechanistic insights related to the formation of protein emulsions and dispersions.

Albumin-Based Nanodevices as Drug Carriers.

Nanomedicine, the application of nanotechnology to medicine, is being increasingly used to improve and exploit the advantages of efficient drug delivery. Different nanodevices have been developed in recent years, among them protein-based nanoparticles which have gained considerable interest. Albumin is a versatile protein carrier with several characteristics that make it an ideal candidate for drug delivery, such as its availability, its biocompatibility, its biodegradability, and its lack of toxicity and immunogenicity.

Assessment of a Protease Inhibitor Peptide for Anti-Ageing.

Ageing and skin exposure to UV radiation induces production and activation of matrix metalloproteinases (MMPs) and human neutrophil elastase (HNE). These enzymes are known to break down the extracellular matrix (ECM) which leads to wrinkle formation. Here, we demonstrated the potential of a solid-in-oil nanodispersion containing a competitive inhibitor peptide of HNE mixed with hyaluronic acid (HA), displaying 158 nm of mean diameter, to protect the skin against the ageing effects.

Size controlled protein nanoemulsions for active targeting of folate receptor positive cells.

Bovine serum albumin (BSA) nanoemulsions were produced by high pressure homogenization with a tri-block copolymer (Poloxamer 407), which presents a central hydrophobic chain of polyoxypropylene (PPO) and two identical lateral hydrophilic chains of polyethylene glycol (PEG). We observed a linear correlation between tri-block copolymer concentration and size - the use of 5mg/mL of Poloxamer 407 yields nanoemulsions smaller than 100nm. Molecular dynamics and fluorescent tagging of the tri-block copolymer highlight their mechanistic role on the size of emulsions.

Peptide Anchor for Folate-Targeted Liposomal Delivery.

Specific folate receptors are abundantly overexpressed in chronically activated macrophages and in most cancer cells. Directed folate receptor targeting using liposomes is usually achieved using folate linked to a phospholipid or cholesterol anchor. This link is formed using a large spacer like polyethylene glycol.

Design of novel BSA/hyaluronic acid nanodispersions for transdermal pharma purposes.

A novel transdermal hyaluronic acid (HA) conjugated with bovine serum albumin (BSA) was developed in the form of solid-in-oil (S/O) nanodispersion (129.7 nm mean diameter). Ex vivo skin penetration analysis by fluorescence and confocal observation of histological skin sections revealed the ability of BSA/HA nanodispersions to cross the stratum corneum and penetrate into the dermis.

Odorant binding proteins: a biotechnological tool for odour control.

The application of an odorant binding protein for odour control and fragrance delayed release from a textile surface was first explored in this work. Pig OBP-1 gene was cloned and expressed in Escherichia coli, and the purified protein was biochemically characterized. The IC₅₀ values (concentrations of competitor that caused a decay of fluorescence to half-maximal intensity) were determined for four distinct fragrances, namely, citronellol, benzyl benzoate, citronellyl valerate and ethyl valerate.

In vitro and computational studies of transdermal perfusion of nanoformulations containing a large molecular weight protein.

Transdermal perfusion of a large protein is reported for the first time, using a nanoemulsion of bovine serum albumin (66kDa) of 160nm prepared by a solid-in-oil (S/O) process. Molecular dynamics simulations confirmed skin permeation by these formulations, with integration of the protein into the lipid bilayers. These results demonstrate the real possibility of delivering large proteins transdermally for a range of medical and cosmetic applications.

The activity of LE10 peptide on biological membranes using molecular dynamics, in vitro and in vivo studies.

Cell-penetrating peptides (CPPs) and antimicrobial peptides (AMPs) are generally defined as small cationic peptides with the ability to interact with lipidic membranes, in a process driven by electrostatic and hydrophobic processes. The interaction with CPPs is known to lead to its translocation across the membrane, while with AMPs lead to membrane damage. Here we present one synthetic anionic peptide, LE10 (LELELELELELELELELELE), which strongly interacts with model membranes, showing properties of CPPs (translocation through lipidic membranes on a mechanism usually described for cationic CPPs) and AMPs (membrane disruption) in molecular dynamic studies, experimental studies with liposomes and mammalian cells in vitro.

Insights on the mechanism of formation of protein microspheres in a biphasic system.

Microspheres of bovine serum albumin (BSA) and silk fibroin are produced by applying ultrasound in a biphasic system consisting of an aqueous protein solution and an organic solvent. The protein microspheres are dispersed in an aqueous media where the protein remains at the interface covering the organic solvent. This only occurs when high shear forces are applied that induce changes to force the protein to the interface.

Molecular recognition of esterase plays a major role on the removal of fatty soils during detergency.

In this work it is describe for the first time, the use of an esterase with null activity (Tfu_0883 bacterial cutinase from Thermobifida fusca) on the removal of fat from the surface of a cotton substrate. Similar levels of fat removal were found for both null and wild-type proteins, despite that only wild type protein yielded fatty acids. Our results show that molecular recognition of esterase plays a major role on the removal of fatty soils, allowing important guidelines for the design of detergent enzymes.

Molecular modeling of hair keratin/peptide complex: Using MM-PBSA calculations to describe experimental binding results.

Molecular dynamics simulations of a keratin/peptide complex have been conducted to predict the binding affinity of four different peptides toward human hair. Free energy calculations on the peptides' interaction with the keratin model demonstrated that electrostatic interactions are believed to be the main driving force stabilizing the complex. The molecular mechanics-Poisson-Boltzmann surface area methodology used for the free energy calculations demonstrated that the dielectric constant in the protein's interior plays a major role in the free energy calculations, and the only way to obtain accordance between the free energy calculations and the experimental binding results was to use the average dielectric constant.

Tailoring elastase inhibition with synthetic peptides.

Chronic wounds are the result of excessive amounts of tissue destructive proteases such as human neutrophil elastase (HNE). The high levels of this enzyme found on those types of wounds inactivate the endogenous inhibitor barrier thus, the search for new HNE inhibitors is required. This work presents two new HNE inhibitor peptides, which were synthesized based on the reactive-site loop of the Bowman-Birk inhibitor protein.