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Abstract A series of mixtures of acrylic copolymer aqueous dispersions or acrylic copolymers and polyurethane water dispersions were used as environmentally friendly base coatings and an acrylic self-crosslinkable copolymer dispersion containing epoxy resin as top coating for natural leather. Samples finished with the proposed additives were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and physical-mechanical tests. FT-IR spectra show that the proposed ecofriendly dispersion used as top coating not only covers the surface of leather, but it is chemically bound with the base coat, assuring a resistant coverage. SEM images show smooth and uniform surfaces. Physical-mechanical characteristics are superior to those imposed by standards in force, demonstrating that the proposed dispersion is able to substitute successfully the top coating nitrocellulose aqueous emulsions (noted EMAL) commonly used as finishing agents, in which the nitrocellulose is dispersed as solution.

ABSTRACT. The paper presents a method for determining hydroxyproline in collagen biomaterials for medical use produced in The Collagen Department of INCDTPDivision ICPI and its validation. The method has two stages: the first one consists in hydrolysis of proteins in the sample of protein product to the form of amino acids, among which hydroxyproline. The second stage refers to selective highlighting of hydroxyproline using a specific colour reaction and quantitative assessment against a reference standard with known concentration. The method was validated to establish performance parameter and to check compliance with the set goal. KEY WORDS: biomaterials, hydroxyproline, validation of method, collagen DETERMINAREA HIDROXIPROLINEI DIN BIOMATERIALELE COLAGENICE PENTRU UZ MEDICAL SI VALIDAREA METODEI REZUMAT. Lucrarea prezinta o metoda de determinare a hidroxiprolinei din biomaterialele colagenice pentru uz medical produse în Departamentul Colagen al INCDTP -Sucursala ICPI si validarea ei. Metoda are doua etape: prima consta în hidroliza proteinelor din proba de produs proteic pâna la stadiul de aminoacizi, printre care si hidroxiprolina. A doua etapa se refera la evidentierea selectiva a hidroxiprolinei printr-o reactie specifica de culoare si evaluarea cantitativa fata de un standard de referinta cu concentratie cunoscuta. Metoda a fost validata pentru a se stabili parametrii de performanta si pentru verificarea conformarii cu scopul propus. CUVINTE CHEIE: biomateriale, hidroxiprolina, validare metoda, colagen LA DÉTERMINATION DE L'HYDROXYPROLINE DANS LES BIOMATÉRIAUX DE COLLAGÈNE POUR UTILISATION MÉDICALE ET LA VALIDATION DE LA MÉTHODERÉSUMÉ. Cet article présente une méthode de détermination de l'hydroxyproline dans les biomatériaux de collagène pour utilisation médicale produits dans le Département de Collagène de INCDTP -Division ICPI et la validation de cette méthode. La méthode comporte deux étapes: la première consiste en l'hydrolyse des protéines dans l'échantillon de produit protéique jusqu'à l'étape d'acides aminés, y compris l'hydroxyproline. La deuxième étape se réfère à la mise en évidence sélective de l'hydroxyproline par une réaction de couleur spécifique et à l'évaluation quantitative contre un étalon de référence de concentration connue. La méthode a été validée pour déterminer les paramètres de performance et pour vérifier la conformité avec le but fixé. MOTS-CLÉS: biomatériaux, hydroxyproline, validation de la méthode, collagène 147Revista de Pielarie Incaltaminte 16 (2016) 2 INTRODUCERECalitatea produselor pentru uz medical este un concept deosebit de complex deoarece, spre deosebire de cea a altor produse industriale, ea are un cuprins mult mai larg ºi efecte mult mai profunde. Dacã pentru majoritatea produselor industriale, calitatea se caracterizeazã printr-o însuºire sau grup de însuºiri fizice ºi chimice bine definite, în cazul produselor pentru uz medical calitatea înglobeazã caracteristici fizico-chimice, biochimice, microbiologice ºi toxicologice. Acestea, prin calitatea lor, au impli...

Compared to the classical systemic administration, the local drug release has some advantages, such as lack of systemic toxicity and associated side effects, increased patient compliance, and a low rate of bacterial resistance. Biopolymers are widely used to design sustained drug delivery systems and biomaterials for tissue engineering. Type II collagen is the indispensable component in articular cartilage and plays a critical role in the growth and proliferation process of chondrocytes. Thus, type II collagen has drawn more attention and interest in the treatment and research of the cartilage regeneration. The aim of this study was to obtain, characterize, and optimize the microcapsules formulation based on type II collagen, sodium alginate, and sodium carboxymethyl cellulose loaded with doxycycline as an antibiotic model drug that could be incorporated further in hydrogels to improve the localized therapy of septic arthritis. The new synthesized microcapsules were assessed by spectral (FT-IR), morphological (optical microscopy), and biological analysis (enzymatic biodegradation, antimicrobial activity). The size distribution of the obtained microcapsules was determined using optical microscopy. The drug encapsulation efficiency was also determined. To optimize the microcapsules’ composition, some physical-chemical and biological analyses were subjected to an optimization technique based on experimental design, response surface methodology, and the Taguchi technique, and the adequate formulations were selected. The results obtained recommend these new microcapsules as promising drug systems to be further incorporated in type II collagen hydrogels used for septic arthritis.