基因重組過的大腸桿菌生產的多精胺酸聚天門冬胺酸(multi-L-arginyl-poly-L-aspartate, MAPA)，由天門冬胺酸(aspartic acid, Asp)和精胺酸(arginine, Arg)和離胺酸(lysine, Lys)所組成，是一種具有生物相容性和潛在藥物傳遞的蛋白質高分子。
本研究藉由Clauson-Kaas Reaction的方式將吡咯(pyrrole)接上水溶性的MAPA，將此分子命名為水溶性多精胺酸聚天門冬胺酸吡咯(sMAPA-g-pyrrole)，隨後再利用傅立葉變換紅外光譜(Fourier-transform infrared spectroscopy, FTIR)以及核磁共振光譜法(Nuclear Magnetic Resonance spectroscopy, NMR)鑑定其結構。
之後，再測試其酸鹼應答的特性，其具有成為陰道藥物釋放系統的可能，故將此高分子進行包覆甲硝唑(metronidazole)的試驗，並且在陰道模擬液下釋放。再利用動態光散射粒徑分析(Dynamic Light Scattering, DLS)和穿透式電子顯微鏡(Transmission electron microscope, TEM)確定粒徑大小與形狀。最後，再以MTT assay來測試此藥物釋放系統對於L929細胞以及E.coli的毒性。

Multi-L-arginyl-poly-L-aspartate (MAPA) produced by recombinant Escherichia coli is composed of aspartic acid (Asp) and arginine (Arg) and lysine (Lys). It is a protein polymer with biocompatibility and potential of drug delivery system.
In this study, pyrrole is attached to water-soluble MAPA by Clauson-Kaas Reaction, then the polymer is named as water-soluble MAPA-pyrrole(sMAPA-g-pyrrole). Use Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR) to identify the structure.
Afterwards, test the pH sensitive, and discover that the polymer has a potential of vaginal drug delivery system. Therefore, use this polymer to package metronidazole(mtz) and test the release from simulated vaginal fluid. Then, use dynamic light scattering particle size analysis (DLS) and transmission electron microscope (TEM) to check the size and shape. At last, use MTT assay to test the toxicity of the drug delivery system to L929 cells and E.coli.

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