Study of electric field caused by semiconductor quantum dots in close proximity to DNA origami

Fluorescent semiconductor quantum dots (QDs) are frequently used in conjunction with biological molecules in a wide variety of applications. A negative 30-nm shift in QD emission has been observed upon binding CdSe QDs to DNA origami, a large scaffolded double-stranded DNA molecule. This paper effectively explains the observed emission shift by modeling the effect of the electric field generated by the DNA origami on the band structure of the QD. A relationship between photon energy shift and QD-origami distance is also presented.