HUVEC biocompatibility and platelet activation of segmented polyurethanes prepared with either glutathione or its amino acids as chain extenders

Abstract

Novel biodegradable segmented polyurethanes (SPUs) were synthesized with polycaprolactone diol, 4,4'-methylen bis (cyclohexyl isocyanate) (HMDI), and either L-glutathione or its constituent amino acids (L-glutamic acid, L-cysteine and glycine) as chain extenders. Fourier transform infrared spectroscopy analysis revealed the feasibility of obtaining polyurethanes through the presence of NH (Amide II), C-N, C-O, and C=O bands and the absence of NCO band. Differential scanning calorimetry and X-ray diffraction revealed that a semicrystalline polymer (T m = 42-52 °C; 2θ = 21.3° and 23°) was obtained in all cases, while dynamic mechanical analysis (DMA) revealed an amorphous phase (T g = -30 to -36 (o)C). These properties, in addition to their high molecular weight, led to high moduli and higher extensibilities when glycine and glutamic acid were used as chain extenders. Clotting times (Lee-White test) and activated partial thromboplastin time determined on these polyurethanes were longer than with glass. In addition, all synthesized SPU exhibited platelet activation indexes below the collagen type I positive control. Human umbilical vein endothelial cells viability was higher in SPUs containing either glycine or cysteine. The obtained results indicate that SPUs that use cysteine as chain extender are promising candidates for cardiovascular applications.

On arginine‐based polyurethane‐blends specific to vascular prostheses

“…Although platelet adhesion experiments were not conducted on blends, pristine polymers showed low values. [19][20][21] The mechanical properties obtained in accordance with D-438ASTM standards provided the intrinsic mechanical properties of the blends as shown in Figure 6. An attempt was made to predict modulus (E Theo ) variation with composition by applying the rule of mixtures:…”

Actividad antibacteriana, degradación hidrolítica y microbiana y citotoxicidad in vitro de poliuretanos sintetizados con polioles derivados del aceite de higuerilla

“…27,28 La degradación acelerada se realizó a 100 °C durante un periodo de 24, 48 y 72 h en buffer fosfato salino siguiendo la metodología descrita por Perales-Alcacio. 11 Para estos ensayos se utilizaron polímeros estériles de 9 mm de diámetro y se colocaron en 5 mL de buffer. Las muestras de los polímeros se retiraron del buffer, se secaron a 40 °C por 24 h y se pesaron.…”

“…Algunas de estas estrategias consisten en modificar la superficie de los PUs por medio de procesos físicos o químicos. 11 La evaluación citotóxica es uno de los estudios in vitro usados comúnmente para determinar la biocompatibilidad de un material y presenta una correspondencia de un 97% con los ensayos de implantación. Es un estudio simple, rápido y económico que proporciona una valiosa información de los materiales que deben ser descartados o aquellos que deben ser sometidos a más estudios.…”

Biocompatibility studies of polyurethane electrospun membranes based on arginine as chain extender

“…Because of skin damage that unprotects the body against infections and sudden changes in the environment [ 5 ], cutaneous scaffolds assist in tissue reparation and regeneration when injury occurs or when a decrease in the patient’s ability to heal occurs [ 1 ]. Despite the biocompatibility of PUs, the main disadvantage is their limited cell recognition and, therefore, low levels of cell adhesion and proliferation [ 6 ], which affects its use as a skin scaffold, since it does not improve the healing time of the wound.…”

“…For improving the biological affinity of the material, different methodologies such as the synthetic and natural polymers combination [ 1 ], the insertion of biomolecules as peptides and/or amino acids on the surface [ 7 ] or in the polymer backbone (as a chain extender) [ 6 ], and the electrospinning process for converting the polymer in nanofibers, have been reported [ 8 ]. In particular, incorporation of amino acids as polyurethane chain extenders can increase the adhesion and proliferation response [ 7 , 9 ].…”