The Role of Bloom Index of Gelatin on the Interaction with Retinal Pigment Epithelial Cells

Biocompatible materials are of considerable interest in the development of cell/drug delivery carriers for therapeutic applications. This paper investigates the effects of the Bloom index of gelatin on its interaction with retinal pigment epithelial (RPE) cells. Following two days of culture of ARPE-19 cells with gelatin samples G75-100, G175, and G300, the in vitro biocompatibility was determined by cell proliferation and viability assays, and glutamate uptake measurements, as well as cytokine expression analyses. The mitochondrial dehydrogenase activity in the G300 groups was significantly lower than that of G75-100 and G175 groups. The Live/Dead assays also showed that the gelatin samples G300 induced mild cytotoxicity. In comparison with the treatment of gelatins with low Bloom index, the exposure to high Bloom strength gelatins markedly reduced the glutamate uptake capacity of ARPE-19 cells. One possible explanation for these observations is that the presence of gelatin samples G300 with high viscosity in the medium may affect the nutrient availability to cultured cells. The analyses of pro-inflammatory cytokine IL-6 expression at both mRNA and protein levels showed that the gelatins with low Bloom index caused less cellular inflammatory reaction and had more acceptable biocompatibility than their high Bloom strength counterparts. These findings suggest that the Bloom index gives influence on cellular responses to gelatin materials

Characterization of soybean protein concentrate-stearic acid/palmitic acid blend edible films

The effect of incorporating commercial stearic acid/palmitic acid blend (SA/PA, 63/37 wt %) into hydrophilic soybean protein concentrate (SPC) film-forming solutions at neutral and alkaline pH on some selected properties of edible cast films was investigated. SA/PA-added SPC film exhibited a significant increase in translucency, being more relevant for films obtained at pH 7. This was associated with the more heterogeneous morphology of such films as observed by scanning electron microscopy. Calorimetric measurements and X-ray diffraction studies confirmed the presence of crystalline fatty acids in films at pH 7 and new crystalline structures at pH 10 due to interactions or reactions between SPC and SA/PA blend. Fourier Transform infrared spectroscopy results confirmed the incorporation of fatty acids into SPC and revealed the occurrence of interactions between both components, depending on the film-forming emulsion pH. Moisture absorption isotherms at high relative humidity (RH) were determined and experimental data were adequately fitted by Peleg's empirical equation. Control SPC films produced at pH 7 were distinctly more moisture resistant than those at pH 10 owing to the more charged protein molecules at alkaline pH. The increased moisture resistance of SA/PA-added-SPC film at pH 10 was related to the more homogeneous dispersion of fatty acid particles within the protein matrix.Fil: De la Caba, K.. Universidad del País Vasco; EspañaFil: Peña, C.. Universidad del País Vasco; EspañaFil: Ciannamea, Emiliano Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Stefani, Pablo Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Mondragon, I.. Universidad del País Vasco; EspañaFil: Ruseckaite, Roxana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentin

ANN prediction of corrosion behaviour of uncoated and biopolymers coated cp-Titanium substrates

The present study focuses on biopolymer surface modification of cp-Titanium with Chitosan, Gelatin, and Sodium Alginate. The biopolymers were spin coated onto a cp-Titanium substrate and further subjected to Electrochemical Impedance Spectroscopic (EIS) characterization. Artificial Neural Network (ANN) was developed to predict the Open Circuit Potential (OCP) values and Nyquist plot for bare and biopolymer coated cp-Titanium substrate. The experimental data obtained was utilized for ANN training. Two input parameters, i.e., substrate condition (coated or uncoated) and time period were considered to predict the OCP values. Backpropagation Levenberg-Marquardt training algorithm was utilized in order to train ANN and to fit the model. For Nyquist plot, the network was trained to predict the imaginary impedance based on real impedance as a function of immersion periods using the Back Propagation Bayesian algorithm. The biopolymer coated cp-Titanium substrate shows the enhanced corrosion resistance compared to uncoated substrates. The ANN model exhibits excellent comparison with the experimental results in both the cases indicating that the developed model is very accurate and efficiently predicts the OCP values and Nyquist plot

Highly reactive thiol-norbornene photo-click hydrogels : toward improved processability

In the present work, gelatin type B is modified with highly reactive norbornene functionalities (Gel-NB) following a one-pot synthesis approach to enable subsequent thiol-ene photo-click crosslinking. The modification strategy displays close control over the amount of introduced functionalities. Additionally, Gel-NB exhibits considerably improved processing capabilities in terms of two-photon polymerization when benchmarked to earlier-reported crosslinkable gelatin derivatives (e.g., gelatin-methacrylamide (Gel-MOD) and gelatin-methacrylamide-aminoethylmethacrylate (Gel-MOD-AEMA)). The improvement is especially apparent in terms of minimally required laser power (20 mW vs >= 60 mW (Gel-MOD) vs >= 40 mW (Gel-MOD-AEMA) at 100 mm s(-1) scan speed) and processable concentration range (>= 5 w/v% vs >= 10 w/v% (Gel-MOD/Gel-MOD-AEMA)). Furthermore, the proposed functionalization scheme maintains the excellent biocompatibility and cell interactivity of gelatin. Additionally, the norbornene functionalities have potential for straightforward postprocessing thiol-ene surface grafting of active molecules. As a consequence, a very promising material toward tissue engineering applications and more specifically, biofabrication, is presented