Department of Biotechnology, Vanung University, Chung-Li, Taiwan, Republic of China.
Bioconjug Chem. 2010 Jan;21(1):28-38. doi: 10.1021/bc900208t.
A series of chitosan (CS) derivatives, the 6-O-carboxymethylchitosan (6-O-CC), 2-N sulfated 6-O-carboxymethylchitosan (N-SOCC) and the 2-N and 3,6-O sulfated 6-O-carboxymethyl chitosan (N,O-SOCC) were synthesized in this study. The chemical structures and the degrees of substituted carboxymethyl and sulfate groups of the synthesized compounds were respectively determined by FT-IR spectra and elemental analysis. N,O-SOCC displayed the highest protective efficiency for basic fibroblast growth factor (bFGF) as examined by the L929 fibroblast culture test and docking simulation. N,O-SOCC-4-thio-butylamidine (TBA) conjugates prepared by modification of N,O-SOCC with 2-iminothiolane were in situ cross-linkable. The degrees of thiol substitution of the 2-iminothiolane modified N,O-SOCC polymers were determined to be in the ranges of 45.9 +/- 3.7 and 415.6 +/- 12.5 micromol SH/g SOCC by quantifying the amount of thiol groups on the thiolated polymers with Ellman's reagent. The 2-iminothiolane modified N,O-SOCC and CS complex could be used for preparing nanoparticles by a polyelectrolyte self-assembly method, and the release of bFGF from the nanoparticles was successfully controlled. L929 fibroblast culture tests showed that the thiol modified N,O-SOCC/CS nanoparticles could effectively protect bFGF from inactivation over a 120 h period. The results of this study suggest that the thiol modified N,O-SOCC/CS nanoparticles may be useful as novel materials for specific delivery of bFGF with mitogenic activity.
本研究合成了一系列壳聚糖（CS）衍生物，包括 6-O-羧甲基壳聚糖（6-O-CC）、2-N 磺酸基 6-O-羧甲基壳聚糖（N-SOCC）和 2-N 和 3,6-O 磺酸基 6-O-羧甲基壳聚糖（N,O-SOCC）。通过傅里叶变换红外光谱（FT-IR）和元素分析分别确定了合成化合物的化学结构和取代的羧甲基和硫酸基团的取代度。通过 L929 成纤维细胞培养试验和对接模拟，发现 N,O-SOCC 对碱性成纤维细胞生长因子（bFGF）具有最高的保护效率。通过对 N,O-SOCC 进行 2-亚氨基硫醇修饰制备了 N,O-SOCC-4-硫代丁基脒（TBA）缀合物，该缀合物可原位交联。通过定量用 Ellman's 试剂测定巯基化聚合物上的巯基量，确定了 2-亚氨基硫醇修饰的 N,O-SOCC 聚合物的巯基取代度分别为 45.9 +/- 3.7 和 415.6 +/- 12.5 micromol SH/g SOCC。通过聚电解质自组装法，可将 2-亚氨基硫醇修饰的 N,O-SOCC 和 CS 复合物用于制备纳米颗粒，并且成功地控制了 bFGF 的释放。L929 成纤维细胞培养试验表明，巯基修饰的 N,O-SOCC/CS 纳米颗粒可有效保护 bFGF 120 h 不被失活。本研究结果表明，巯基修饰的 N,O-SOCC/CS 纳米颗粒可能是具有有丝分裂活性的 bFGF 特异性递送的新型材料。
