Formation of circular patterns of calcium oxalate crystals at defective sites of Langmuir–Blodgett films

The circular patterns of calcium oxalate (CaOxa) crystals were first induced at defective sites of LB film of DPPC injured by potassium oxalate. As the crystallization time extend, the pattern of the crystals changed from a ring-shape to a solid circle. In comparison, the LB films without oxalate pretreatment only induced randomly growth of crystals. It was attributed to the destruction of molecular rearrangement at the boundaries of liquid condensed (LC) and liquid expanded (LE) phases of the LB film caused by oxalate. This model system might be used to mimic formation of CaOxa stones at surface of damaged renal epithelial membranes.