To develop a novel biodegradable collagen-chitosan-[poly(vinyl alcohol), PVA] composite artificial lacrimal canal iculus for treating tear overflowing (epiphora) caused by canal icular obstruction. Methods Homogeneously mixing solution composed of collagen, chitosan and PVA with different ratios was prepared. After several cycles of freezing/thawing process, the mixing solution was transferred into elastic hydrogel. Then the hydrogel was rinsed, punctured, dehydrated and trimmed, and three groups (T1, T2 and T3) of novel artificial lacrimal canal iculus were obtained. The appearance and diameter of all samples were observed under optical microscopy. The cross-section before and after drying as well as phase distribution of sample T2 was observed by SEM. The water absorption ratio and expanding ratio in PBS solution were calculated from three swell ing behavior curves. The degradabil ity of groups T1, T2 and T3 were prel iminary analyzed by degradation experiment in vitro. Results The micro-tubes with 0.5-0.7 mm in inner diameter, 0.9-1.5 mm in outer diameter and more than 20 mm in length were fabricated successfully through physical crossl inking without addition of toxic cross-l inker. SEM result showed that the sample had uniform phase distribution and smooth surface at dried state as well as interpenetrate network structure at hydrogel state. It was seen from the swell ing behavior curves that groups T1, T2 and T3 swelled rapidly within 10-30 minutes, and formed elastic composite hydrogel pipes. In addition, the expanding ratio of inner and outer diameter of the tube was 20%-30% and 100%-120% with swell ing, respectively. The equil ibrium water content of the hydrogel pipes increased with increase of collagen composition. Three groups of samples were immerged in PBS solution contained 2 mg/mL lysozyme at 37 for 1 month, their nozzle cracked, their wall became thin and more transparent. And also, there was small floc deposited on the tube surface. The samples were degraded into mash after they were soaked in PBS solution at 70 for 2 days. Conclusion The novel artificial lacrimal canal iculus with good mechanical property and high water absorption is in favor of operation, tear passing and anti-conglutination. It will be a potential candidate for treating the lacrimal passage occlusion.
Citation： ZHENG Guiqiu,JIANG Lixia,GU Qisheng,WANG Xiaomin. PREPARATION AND CHARACTERIZATION OF NOVEL DEGRADABLE ARTIFICIAL LACRIMAL CANALICULUS. Chinese Journal of Reparative and Reconstructive Surgery, 2008, 22(7): 856-860. doi: Copy