經由基因重組大腸桿菌所生產的多精胺酸聚天門冬胺酸(multi-L-arginyl-poly-L-aspartate, MAPA)，也被稱為藍藻蛋白(cyanophycin granule polypeptide, CGP)，主鏈為天門冬胺酸 (aspartic acid, Asp)，側鏈為精胺酸(arginine, Arg)和離胺酸(lysine, Lys)所組成的，是一種非核糖體合成的天然蛋白質，具有好的生物相容性、酸鹼應答、高臨界溶解溫度(upper critical solution temperature, UCST)溫敏性的智能高分子。
本研究利用Traut's reagent對水溶性藍藻蛋白巰基(thiol group)加成反應，再利用succinimidyl 3-(2-pyridyldithio)propionate (SPDP)與抗癌藥物阿黴素(doxorubicin)反應，將sMAPA-SH、py-ss-Dox以不同比例的反應合成，命名為sMAPA-SS-Dox，並以傅立葉變換紅外光譜(Fourier-transform infrared spectroscopy, FTIR)鑑定官能基和核磁共振光譜法(Nuclear Magnetic Resonance spectroscopy, NMR)確定分子結構。
隨後以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。在不同濃度下測試不同接枝率的sMAPA-SS-Dox和Dox對黑色素腫瘤細胞的毒殺能力，以MTT法測試其相對存活率。

Multi-L-arginyl-poly-L-aspartate (MAPA), also known as cyanophycin granule polypeptide (CGP), simply cyanophycin, is prepared with the recombinant Escherichia coli. It consists of an aspartic acid (Asp) backbone with arginine (Arg) and lysine (Lys) as side chains. It is a non-ribosomal polypeptide that has been shown to possess good biocompatibility, acid-base response, and upper critical solution temperature (UCST) temperature type response.
In this study, sulfhydryl groups were introduced to the soluble cyanophycin using Traut’s reagent to obtain sMAPA-SH. The anticancer drug, Doxorubicin, was modified using SPDP (succinimidyl 3-(2-pyridyldithio) propionate) acquiring Py-SS-Dox. A conjugated product, named sMAPA-SS-Dox, was prepared by combining two modified compounds in different proportions, and the molecular structure is determined through Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR).
Subsequently, the particle size distribution and shape of the obtained product was determined using Dynamic Light Scattering (DLS) and transmission electron microscope (TEM). The toxicity of the particles prepared in different proportions to Melanoma Tumor cells was determined at different concentrations, and the cellular viability was determined through MTT assay.

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