Synthesis of 5-Fluorouracil conjugated LaF3:Tb3+/PEG-COOH nanoparticles and its studies on the interaction with bovine serum albumin: spectroscopic approach

Abstract

The luminescent lanthanide-doped nanoparticles have gathered considerable attention in many fields especially in biomedicine. In this work, the lanthanum fluoride-doped terbium nanoparticles (LaF 3 :Tb 3? NPs) via simple chemical precipitation method has been synthesized and functionalized with polyethylene glycol. The size and the shape of the nanoparticles are confirmed using X-ray diffraction and transmission electron microscopy. The conjugation of 5-Fluorouracil (5-FU) and thus synthesized nanoparticles (NPs) were confirmed using various spectroscopic methods such as UVVisible spectroscopy, fluorescence steady state, and excited state spectroscopy studies. The enhancement in fluorescence emission (k = 543 nm) of drug-conjugated nanoparticles confirms the Vander Waals force of attraction due to F-F bonding between the drug and the nanoparticles. Further, the effects of 5FU-NPs in carrier protein were investigated using bovine serum albumin as a protein model. The 5FU-LaF 3 :Tb 3? nanoparticles binding is illustrated with binding constant and number of binding sites. The structural change of bovine serum albumin has been studied using circular dichroism and Fourier transform infrared spectroscopy analysis. Graphical AbstractKeywords Lanthanum fluoride Á 5-Fluorouracil Á Serum albumin Á Fluorescence quenching Á Vander Waal force of attraction

Comparative structural and optical spectroscopic studies of Nd3+ ion doped LaF3 and their core/shell nanoparticles

“…2b) shows the polycrystalline diffraction rings corresponding to the specific (002), (111), (300), (302) and (221) planes of the hexagonal LaF 3 lattice (ICDD No. 32-0483) [24][25][26] and therefore indicates that the obtained NPs are all highly crystalline and maintain the same hexagonal crystal structure during the synthesis process and are in good agreement with the observed X-ray diffraction results. EDX analysis was also performed to examine the surface silica coating on the core NPs (Fig.…”

“…1, which are consistent with the ICDD No. 32-0483 and other literature data [24][25][26]. No second phase corresponding to an impurity was detected in the XRD patterns revealing that Nd 3+ has been effectively doped into the host lattice of hexagonal LaF 3 NPs.…”

Photostability of quantum dot micelles under ultraviolet irradiation

“…From the excited state lifetime measurements, biotin modified micelles had a slightly longer lifetime (11.42 ns) compared to the others (PEG: 7.04 ns and folate: 8.11 ns). The decay curve of the micelles fit well to a bi‐exponential function using the formula given in Table . The hydrodynamic diameters of the micelles were measured by a DLS method (Table ).…”

Biocompatible CdSe/ZnS quantum dot micelles for long-term cell imaging without alteration to the native structure of the blood plasma protein human serum albumin

“…Native HSA contains two negative peaks at 208 and 222 nm and has an a-helical content of 67.45% AE 0.73%. 32,35 Aer serial addition of micelles at concentrations of 2, 4, and 6 mM, the ahelical content increased to 70.05% AE 0.81%, 72.24% AE 0.77%, and 74.11% AE 0.68%, respectively. However, the shape and positions of the protein peaks were unaltered in the presence of micelles.…”