Abstract: Defective LB film was used as model for injured renal epithelial membrane to induce the growth of calcium oxalate monohydrate (COM) crystals, which was the major inorganic component found in renal calculi. After the LB film of dipalmitoylphosphatidylcholine (DPPC) was treated by 2.5 mmol·L-1 potassium oxalate, the structural differentiation between liquid expanded (LE) phase and liquid condensed (LC) phase in LB film was strengthened and circular defects appeared. These circular defects were proved by atomic force microscopy (AFM). Such circular defects could induce ring-shaped patterns of COM crystals. In comparison, the LB films without pretreatment by potassium oxalate only induced randomly growth of COMcrystals.

Key words: Defective LB Film, Biomineralization, Calciumoxalate, AFM