Nair Lakshmi S, Starnes Trevor, Ko Jia-Wei Kevin, Laurencin Cato T
Department of Orthopaedic Surgery, University of Virginia, Virginia 22903, USA.
Biomacromolecules. 2007 Dec;8(12):3779-85. doi: 10.1021/bm7006967. Epub 2007 Nov 10.
Thermosetting polymers are attractive candidates for biomedical applications as noninvasive therapeutic delivery vehicles. In the present study, the feasibility of developing a neutral physiological temperature setting injectable formulation based on chitosan and an inorganic phosphate salt have been demonstrated. The in situ gelling system was developed by adding different concentrations of ammonium hydrogen phosphate (AHP) to chitosan solution. The resulting solutions have pH in the range of approximately 7-7.2. The gelling time of the chitosan-AHP solution was determined by incubating the solutions at 37 degrees C. Depending on the concentrations of AHP added, the gelling time varied from 5 min to 30 h at 37 degrees C. Addition of various diluents to chitosan-AHP solution did not significantly change the gelling time of the solutions. The gels were found to be cytocompatible as evidenced from in vitro cytocompatibility evaluation using MC3T3-E1 mouse osteoblast like cells. The feasibility of using the gels as a stem cell carrier vehicle as well as a macromolecular delivery vehicle has been demonstrated.
热固性聚合物作为无创治疗递送载体，是生物医学应用中颇具吸引力的候选材料。在本研究中，已证明了开发基于壳聚糖和无机磷酸盐的中性生理温度设定可注射制剂的可行性。通过向壳聚糖溶液中添加不同浓度的磷酸氢铵（AHP）来开发原位凝胶系统。所得溶液的pH值在约7 - 7.2范围内。壳聚糖 - AHP溶液的凝胶化时间通过在37℃下孵育溶液来确定。根据添加的AHP浓度，在37℃下凝胶化时间从5分钟到30小时不等。向壳聚糖 - AHP溶液中添加各种稀释剂不会显著改变溶液的凝胶化时间。使用MC3T3 - E1小鼠成骨样细胞进行的体外细胞相容性评估表明，这些凝胶具有细胞相容性。已证明了将这些凝胶用作干细胞载体以及大分子递送载体的可行性。
