[Influence of the gelatin-alginate matrixes with calcium lactate in plasma coagulation system after implantation in soft tissues]. / Wplyw matryc zelatynowo-alginianowych z mleczanem wapnia na osoczowy uklad krzepniecia po implantacji w tkanki miekkie.

BACKGROUND: Bioresorbable porous substrates from copolymers have their application in tissue engineering to culture tissues in vitro. The advantage of polymers is the production of thermoplastic elements and their ability to biodegrade in a living body. Gelatin, collagen, alginates are part of dressings used for topical administration of the drug. Research was undertaken to achieve a porous gelatin-alginate matrix which could be used in therapy as among others, a carrier for a drug. OBJECTIVES: Evaluation of the impact of modified gelatin-alginate matrix on activation of plasma coagulation in vivo. MATERIAL AND METHODS: Gelatin-alginate matrix cross-linked with calcium ions was implanted in the muscle tissue of a rat. The control group constituted animals not implanted with material, but they passed the operating procedure. Blood samples of plasma coagulation test and control group were collected after 1, 2, 3, 5, 7, 10, 14 days of the procedure. RESULTS: Prolongation of APTT and shortening of PT and TT with the unchanged values of fibrinogen and the count of platelet cells was observed till the 5th day on the basis of the obtained results. Prolongation of APTT with the unchanged values of the remaining parameters of the coagulation system was observed after 7, 10 and 14 days with unchanged values of PT and TT coagulation. CONCLUSIONS: The matrix gelatin-alginate with calcium ions in the biological environment undergoes biodegradation in soft tissues. This process in the initial period influences the activation of the coagulation within the intrinsic and extrinsic system. From the 5th to 14th day the activation of coagulation was observed only in the intrinsic system.

[Influence of gelatin-alginian matrixes on morphological and functional changes of blood leukocytes]. / Wplyw matryc zelatynowo-alginianowych na zmiany morfologiczne i czynnosciowe leukocytów krwi.

BACKGROUND: Knowledge of the relation of biomaterials and living tissues constitutes necessary information which should be used when composing a set of optimal carriers, e.g. for drugs or preparations supporting blood clotting. OBJECTIVES: This paper presents an assessment of the influence of contact of gelatin-alginian matrixes with blood on leukocyte reactivity: the ability of mononuclear cells (lymphocytes and monocytes) to create a radial segmentation of nuclei--RS (the morphological change), and the ability of leukocytes to phagocytosis of yeast Saccharomyces cerevisiae cells and to produce active oxygen derivatives (functional changes). MATERIAL AND METHODS: After having contact with the matrixes, the test of induced and spontaneous RS, the phagocytic test and nitroblue tetrazolium reduction test for blood leukocytes were performed. RESULTS: The obtained results showed a decrease in the ability of mononuclear cells to form RS and in the ability of granulocytes to reduce nitroblue tetrazolium--NBT, but an increase in their phagocytic activity. CONCLUSIONS: Temporary contact of gelatin-alginian matrixes with blood did not cause any morphological changes in the leukocytes. However, changes of their reactivity were observed.

Properties and active substance release kinetics from gelatin-alginate matrices.

The aim of the study was to evaluate the effect of composition and technological processing on pharmaceutical availability of active substance as well as on the properties of porous gelatin-alginate matrices. The active substance carrier included glycerol or peanut oil apart from gelatin and sodium alginate, and some matrices were additionally modified with calcium lactate. The obtained matrices were characterized by good sorption properties and high resistance to proteolytic enzymes. The release of the model antibiotic followed the pattern of first order kinetics, while half-release time in vitro (in the experimental conditions) was 1.5 to 3 hrs.

Effect of composition on the physicochemical properties and active substance release from gelatin-alginate sponge.

The aim the study was physicochemically characterize and develop ability of the active substance (cefradine) from the implantable porous carriers. The drug delivery systems consisting of the gelatine and alginic acid sodium salt and glycerol (GL) or peanut oil (AO). Gelatin-alginate sponge was prepared by foamed components and next freeze-dried this foam. The composition of the sponges affected on the sorption ability and on the stability to proteolytic enzymes. Owing to porous structure obtained specific profile of active substance release.

The effect of composition upon the physical and chemical properties of biodegradable gelatin polymer matrixes.

The aim of the research was to obtain porous, elastic gel matrix with a long decomposition time as a carrier of therapeutic substance. The pigskin gelatin of various degrees of gelation and glycerol was used in the experiment. The studies showed that such biopolymer as gelatin is enable to prepare the matrix which can remain in organism for a long time and a porous structure of the sponge allows to increase absorbing capacity of exudate.