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The effect of graphene oxide (GO) and nanodiamond (ND) is investigated on the spectral properties of doxorubicin (DOX) fluorescence emissions in the form of (DOX+GO) and (DOX+ND) biomaterials. It is shown that carbon nanostructure additives lead to sensible blueshifts, due to their optical properties and surface functionality. The quenching coefficient K is obtained to be K=0.043  (μg/ml) and K=0.342  (μg/ml) in DOX solutions. In general, Stern-Volmer attests that excited (DOX+GO) strongly quenches with respect to that of (DOX+ND) regarding its privileged bonding affinity.

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The excimer laser at 193 nm induces regular self-assembled microstructures on poly allyl diglycol carbonate PADC (or CR-39). This surface rippling is threshold-dependent and undergoes different features at low/high UV fluences. The microstructures are characterized by small/large aspect ratios (0.056-0.226) at low/high UV fluences of 40-1000 mJ cm −2 . The self-aligning micro grooves show a strong sensitivity to the incident angles. As a consequence, the parameter of the fluence threshold drastically reduces in terms of the large incident angles, leading to parallelism over a broad treated area. In fact, the self-rippling at high UV fluences aligns with P-polarization of the incident beam. Conversely, the pattern appears in the orientation of the S-polarization under low fluences. This unique property of CR-39 is used to fabricate the micro gratings of 250-2900 lines mm −1 , which certainly meets the criteria for high efficiency at small aspect ratios.

ArF excimer laser at λ = 193 nm induces the regular macrostructures on poly methyl methacrylate (PMMA) and CR-39 with the periodicity Λ under the proper UV doses. The periodic self-organizing pattern lucidly appears on the polymeric surface, creating the grooves parallel along with the direction of the focal line of the cylindrical lens. The spatial period Λ is enlarged in terms of the focal length f varying tens of microns, much larger than the laser wavelength (22–145 μm, Λ ≫ λ). The interspacing also alters in terms of the incident angle θ by the expression 1/ cos θ, however it remains nearly invariant against the laser fluence F ranging several hundreds of mJ/cm2. Finally, the crisscross macroripples are created by situating a couple of cylindrical lenses in the orthogonal configuration. The formation of the gridiron patterns on PMMA and CR-39 attests that the linear superposition holds accordingly.