Coacervates are dense aqueous phases that form by liquid-liquid phase separation. Seven Pt(II) complexes with different charges and nucleotide reactivities were examined for their ability to induce co Show more
Coacervates are dense aqueous phases that form by liquid-liquid phase separation. Seven Pt(II) complexes with different charges and nucleotide reactivities were examined for their ability to induce coacervate formation in a 21-mer single-stranded DNA (ssDNA). Only AMPZ ([cis-{Pt(NH3)2}2(μ-pyrazolato)(μ-OH)](NO3)2), a cationic dinuclear Pt(II) complex, efficiently induced coacervate formation in ssDNA containing only thymine (T21-DNA). AMPZ has very low reactivity with thymine but relatively high reactivity with guanine, and when three of the thymines in T21-DNA were substituted with a guanine to produce T18-G3-DNA, the resulting coacervate was observed to undergo gelation via the formation of an extensive Pt-DNA coordination-bonded network. We then examined the construction of coacervates that comprise multiple phases by adding AMPZ to a mixture of two types of ssDNAs, a highly reactive T10-G11-DNA and a minimally reactive T21-DNA, and found that two distinct assembly states─a cell mimetic assembly and a DNA-encapsulating gel─could be formed. Show less