The process for the preparation of nanoparticles from polysaccharides and derivatives thereof, by their specific partial oxidation to produce aldehyde groups and attach compounds with amino or other group with the R-NH2 bond which react with aldehyde groups, comprising oxidizing the polysaccharide or derivative thereof by a known method to obtain aldehyde groups until the oxidation degree of 0,1% to 80% of the sugar rings is obtained, then adding at least one nanoparticle-forming agent which after attachment of the aldehyde group exhibits hydrophobic properties, selected from the group comprising: aliphatic or aromatic organic amines containing from 4 to 20 carbon atoms, amides and hydrazides of aliphatic and aromatic organic acids containing from 4 to 20 carbon atoms, hydrophobic amino acids, phosphatidylethanolamine, and at least one active substance containing at least one amino, amido or hydrazide group, to the solution of the oxidized polysaccharide in water or a mixture of water and an organic solvent, carrying the reaction out at pH of the solution from 1 to 9, at the temperature of from 10 to 100°C, wherein the total molar ratio of amino groups to aldehyde groups is from 20 to 0,5.El proceso para la preparación de nanoparticulas de polisacáridos y derivados de estos, a través de su oxidación parcial específica para producir grupos aldehídos y unir compuestos con grupos aminos u otros grupos con el enlace R-NH2 que reacciona con grupos aldehídos, incluyendo la oxidación de los polisacáridos o sus derivados, mediante un método conocido para obtener grupos aldehídos hasta que el grado de oxidación de 0,1% a 80% de los anillos de azúcar se obtiene. Luego se agrega al menos un agente formador de nanopartículas, que después de la adjunción del grupo aldehído exhibe propiedades hidrofóbicas, seleccionado del grupo y compuesto por: aminos alifáticos o aromáticos que contienen de 4 a 20 átomos de carbón, aminoácidos hidrofóbicos, fosfatidiletanolamina, y al menos un
