Self-forming hybrid compositions consisting in admixed liquid and solid components enable the formation of bio-materials. The present invention proposes a) a thermo-sensitive self-forming liquid component, being water-based and containing at least a polycationic polymer such as chitosan, and an organic mono-phosphate source, which is a solution at a pH ranging from 6.5 to 7.4; b) a solid component being mineral and composed of at least one of calcium, fluoride, strontium, carbonate and phosphate salts. Solid mineral salts preferentially have a recognized bioactive potential such as the calcium phosphate salts for bones. Both solid and liquid components are admixed to form an injectable liquid slurry or pre-gelled paste that turn in situ into a hybrid uniform gel-like bio-material.