The present invention provides a novel liquid composition suitable for in-situ formation of a depot system to deliver a bioactive substance in a controlled manner. The composition of the present invention comprises: (a) a hydrophobic non-polymeric carrier material； (b) a water miscible biocompatible organic solvent that dissolves the hydrophobic non-polymeric material； (c) an ionic complex that is formed between an amphiphilic molecule and a bioactive substance having a net charge at neutral pH in water. The present invention also provides a method of manufacturing and use of the composition thereof.
