Novel fluorescent nanocomposites (NCs) were generated using ions of Au(III), Ag(I), Fe(II) in conjunction with bovine serum albumin (BSA). BSA served as a template and simultaneously as a reducing agent. Au(III) was selected for the formation of fluorescent AuNCs in the presence of BSA (1); Ag(I) was employed in order to enhanced fluorescence intensity of NCs (2); and Fe ions were chosen as precursors for the formation of a contrast agent being employed in ¹H magnetic resonance imaging (MRI) (3). Two molar ratios of Au and Ag ions used in the course of the synthesis of NCs substantially influenced NCs fluorescence intensity, as well as the characteristic fluorescence peak position. On the other hand, it was revealed that Fe ions did not affect position of fluorescence peak maximum and had only a slightly negative effect on the fluorescence intensity of NCs with metal cations molar ratio of 5-1-1 (whereas no iron ions effect on fluorescence intensity was observed for the ratio of 5-2-2). At sufficiently elevated Fe ions concentrations, these novel NCs can be used for MRI without significant fluorescence signal quenching.

Acknowledgement:

This research was funded by Grant Agency of the Czech Republic, grant number 19-03207S, and Internal Grant Agency of Palacky University, grant number IGA_PrF_2021_017.

References:

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