Linear and nonlinear optical properties of DNA in suspensions

Deoxyribonucleic acid (DNA) has the potential to serve as inexpensive, functionalized photonic material. Previous research has mostly focused on dry DNA thin films; however, little is known regarding the properties and photonics applications of DNA solvents. This paper compares the linear and nonlinear optical properties of different sized DNA in suspensions. In particular, small plasmid DNA, long lambda DNA, and extra-long strawberry DNA were studied. The linear optical properties were evaluated in terms of UV- Vis spectrophotometry, and the nonlinear optical properties were investigated using the closed-open continuous wave Z-scan technique. In addition, the paper investigated DNA suspension survivability to prolonged exposure to a 532 nm green laser. The results showed DNA structural integrity after the 532 nm laser exposure and optical characteristics comparable to synthetic polymers, indicating that DNA suspensions could be a good optical material for photonic devices and optoelectronics applications. • Investigation of linear and nonlinear optical properties of DNA in TE buffer, focusing on plasmid, lambda, and strawberry DNA. • DNA suspensions demonstrate stability, with minimal impact after 1 hour of exposure to a 532 nm laser. • Nonlinear absorption coefficients of DNA in TE buffer are on the order of 6 x 10 -7 cm/W, with only slight increases observed across different DNA types. • Nonlinear refractive index values for DNA suspensions range from 5 x 10 -12 to 12 x 10 -12 cm 2 /W, showing a clear increase with DNA size. • The observed trends suggest that DNA size and conformation significantly influence its nonlinear refractive properties.