Silicon complex (I) formed by reacting orthosilicic acid having four free hydroxy groups and at least one stabilizing agent based on phenol or polyphenol, is new, where the free hydroxy groups of orthosilicic acid is stabilized by hydrogen bonding. An independent claim is included for liquid biological preparation comprising (I), where the liquid biological preparation exhibits a pH of 2-4, the amount of silicon is 0.3-1.4 wt./vol.% and the ratio between the amount of silicon and stabilizing agent is 0.1:1.Complexe de silicium biodisponible, stable, formé entre de lacide orthosilicique présentant quatre groupes hydroxyle libres et au moins un agent de stabilisation à base de phénol ou de polyphénol, stabilisant par liaison hydrogène lesdits groupes hydroxyle libres de lacide orthosilicique, son procédé de préparation et son utilisation.
