Keratin–cinnamon essential oil biocomposite fibrous patches for skin burn care

Keratin based electrospun fibres containing cinnamon essential oil are highly antioxidant and antibacterial, and promote reduced tissue inflammation after skin burns

A thermoresponsive and magnetic colloid for 3D cell expansion and reconfiguration

A dual thermoresponsive and magnetic colloidal gel matrix is described for enhanced stem-cell culture. The combined properties of the material allow enzyme-free passaging and expansion of mesenchymal stem cells, as well as isolation of cells postculture by the simple process of lowering the temperature and applying an external magnetic field. The colloidal gel can be reconfigured with thermal and magnetic stimuli to allow patterning of cells in discrete zones and to control movement of cells within the porous matrix during culture

Multifunctional poly[N-(2-hydroxypropyl)methacrylamide] copolymers via postpolymerization modification and sequential thiol–ene chemistry

Poly[N-(2-hydroxypropyl)methacrylamide] is a promising candidate material for biomedical applications. However, synthesis of functional pHPMA via compolymerization results can lead to variations in monomer composition, molar mass, and dispersity making comparison difficult. Postpolymerization modification routes, most commonly aminolysis of poly[active ester methacrylates], have alleviated some of these problems, but ester hydrolysis can lead to other problems. Here we report the synthesis of multifunctional pHPMA via a simple two-step derivatization of pHPMA homopolymer using readily available standard reagents and atom-efficient procedures. First, treatment with allyl isocyanate yields the corresponding carbamate with predictable incorporation of side-chain functionality. Allyl-pHPMA can then be derivatized further via radical thiol–ene reactions to generate pHPMA with multiple diverse functionalities but without adverse effects on the molecular weight and dispersity of the polymer. The applicability of the method to production of biologically relevant materials is demonstrated by cytocompatibility and cell labeling experiments with easily prepared ligand-functionalized pHPMA in the HCT 116 model cell line

PH responsive Smart polymers for advanced drug delivery

Synthesis of AB diblock copolymers from a novel imidazole based monomers, that are able to respond at variation of PH (acidic tumor environment). Characterization of the copolymers by titration, turbidimetric analysis, dynamic light scattering and critical unicellar concentration determination

Synthesis and characterization of variable conformation pH responsive block co-polymers for nucleic acid delivery and targeted cell entry

Responsive materials that change conformation with varying pH have been prepared from a range of amphiphilic block co-polymers. The individual blocks are composed of (a) permanently hydrophilic chains with neutral functionality and (b) acrylate polymers with weakly basic side-chains. Variation in co-monomer content, molar mass and block ratios/compositions leads to a range of pH-responses, manifest through reversible self-assembly into micelles and/or polymersomes. These transitions can be tuned to achieve environmental responses in a pH range from 5\u20137, as shown by turbidimetric analysis, NMR and dynamic light scattering measurements (DLS). Further characterization by transmission electron microscopy (TEM) indicates that polymersomes with diameters of 100\u2013200 nm can be formed under certain pH-ranges where the weakly basic side-chains are deprotonated. The ability of the systems assembled with these polymers to act as pH-responsive containers is shown by DNA encapsulation and release studies, and their potential for application as vehicle for drug delivery is proved by cell metabolic activity and cell uptake measurements

A study of the effects of imidacloprid under laboratory and field conditions on nymphs of Triatoma infestans (Hemiptera: Reduviidae)

The aim of this study was to determine imidacloprid’s lethal activity against fifth-instar nymphs of Triatoma infestans. In the first stage of this work, it was assayed the topical application of this insecticide on non-fed and repletion-fed nymphs. Results showed a DL50 three times greater in non-fed bugs than in those fully engorged. The presence of food determined less time for the insecticide’s maximum lethal effect: 24 h post topical application in fed nymphs and 72 h in non-fed nymphs. In the study’s second stage, we assayed a xenointoxication assay on dogs. The commercial products, Advantage®, Bayer (imidacloprid 10 % p/v) and Power Ultra®, Brouwer (imidacloprid 5.15 %, permethrin 40 % and piperonyl butoxide [PBO] 3%) were evaluated. Following administration of the insecticide, nymphs were fed on dogs 24, 72, 168, 240 and 336 h. Blood intake was similar in nymphs exposed to treated dogs versus controls. Although both commercial products showed low triatomicidal activity, a higher efficacy of the product combining imidacloprid with the synergist piperonyl butoxide and permethrin versus the product with imidacloprid as the only active ingredient was observed, causing in nymphs a mortality rate of 36.3 % and 20.7 %, respectively. Our results suggest that imidacloprid, alone or in combination with permethrin and PBO, is not an alternative for control of T. infestans.Fil: Dadé, Martin Miguel. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Daniele, Martin Rafael. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Silvestrini, María P.. Universidad Nacional del Centro de la Provincia de Buenos Aires; ArgentinaFil: Bozzolo, Facundo Oscar. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Francini, Flavio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnol.conicet - la Plata. Centro de Endocrinología Exp.y Aplicada (i). Grupo Vinculado Cenexa-fcex-unlp; ArgentinaFil: Mestorino, Olga Nora. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnol.conicet - la Plata. Centro de Endocrinología Exp.y Aplicada (i). Grupo Vinculado Cenexa-fcex-unlp; Argentin

Multifunctional Poly[<i>N</i>‑(2-hydroxypropyl)methacrylamide] Copolymers via Postpolymerization Modification and Sequential Thiol–Ene Chemistry

Poly­[<i>N</i>-(2-hydroxypropyl)­methacrylamide] is a promising candidate material for biomedical applications. However, synthesis of functional pHPMA via compolymerization results can lead to variations in monomer composition, molar mass, and dispersity making comparison difficult. Postpolymerization modification routes, most commonly aminolysis of poly­[active ester methacrylates], have alleviated some of these problems, but ester hydrolysis can lead to other problems. Here we report the synthesis of multifunctional pHPMA via a simple two-step derivatization of pHPMA homopolymer using readily available standard reagents and atom-efficient procedures. First, treatment with allyl isocyanate yields the corresponding carbamate with predictable incorporation of side-chain functionality. Allyl-pHPMA can then be derivatized further via radical thiol–ene reactions to generate pHPMA with multiple diverse functionalities but without adverse effects on the molecular weight and dispersity of the polymer. The applicability of the method to production of biologically relevant materials is demonstrated by cytocompatibility and cell labeling experiments with easily prepared ligand-functionalized pHPMA in the HCT 116 model cell line

Polymers for binding of the gram-positive oral pathogen <i>Streptococcus mutans</i> - Fig 3

<p>Binding of coumarin 343-tagged a) cationic <b>(3)_25-100%</b> and b) sulfobetaine <b>(4)_25-100%</b> polymers at different degrees of functionalization, to <i>E</i>. <i>coli</i> and <i>S</i>. <i>mutans</i> in bacterial suspensions of OD₆₀₀ 0.1, and 1.0 mg mL^-1 polymer solutions. Area of fluorescence (%) was quantified using ImageJ. Error bars represent standard deviations on independent experiments (N = 3). Fluorescence micrographs are shown for fully functionalised (c, d) cationic and (e, f) sulfobetaine polymers, <b>(3)</b>_<b>100%</b> and <b>(4)</b>_<b>100%</b>, respectively using the 488 nm (green) channel.</p

インド デ ヌノ オ サワル

<p>(A) Binding of coumarin 343-tagged sulfobetaine polymer <b>(4)</b>_<b>100%</b> to <i>E</i>. <i>coli</i>, <i>S</i>. <i>mutans</i>, <i>V</i>. <i>Harveyi</i> and <i>S</i>. <i>Aureus</i> in bacterial suspensions of OD₆₀₀ 0.1, and 1.0 mg mL^-1 polymer solutions (scale bars = 5 μm). Representative fluorescence micrographs are shown using the green channel (488 nm excitation). Area of fluorescence (%) was quantified using ImageJ. Error bars represent standard deviations of three equivalent areas on three different micrographs. (B) Bacterial aggregation mediated by sulfobetaine polymer <b>(4)</b>_<b>100%</b>, as quantified <i>via</i> master sizer (Coulter counter) analysis of polymer—bacteria clusters.</p