According to common knowledge, a single bond or a linker group having 1 to 6 carbon atoms are known not affecting water solubility of the molecule having strong electrolytic groups such as the 000H group in the present invention. Besides, the said L1, L2, and L3 group are the backbone of a polyamine, a poly-carboxylic acid or a carboxylic acid anhydride. According to common knowledge, the L1 and L3 groups do not affect the reactivity in the amide bond formation.