Circular dichroism (CD), UV-vis absorption, fluorescence, and resonance light scattering (RLS) spectroscopies were used to elucidate the role of the DNA sequence, linkers between DNA and porphyrin, and metal in the porphyrin coordination center on the self-assembly of DNA-porphyrin conjugates. A series of eight non-self-complementary DNA-porphyrin conjugates have been synthesized with zinc and free-base porphyrins covalently attached to the short ODNs (A 8 or T 8) via amide or phosphate linker. A small structural modification (e.g., amide linker replaced by the phosphate linker) showed a dramatic effect on the aggregation properties of DNA-porphyrin conjugates and greatly altered their spectroscopic properties. At low ionic strength, porphyrin aggregation was not observed for any conjugate. An increase in the ionic strength caused two out of eight conjugates to form chiral porphyrin dimers.
Bibliographical noteFunding Information:
M.B. thanks the UW start-up grant and the School of Energy Resources . G.S. thanks the School of Energy Resources Graduate Assistantship. B.L.M. was supported by the University of Wyoming NSF REU program .
All Science Journal Classification (ASJC) codes
- Drug Discovery
- Organic Chemistry