Exploring 99mTc-Labeled Iron-Binding Glycoprotein Nanoparticles as a Potential Nanoplatform for Sentinel Lymph Node Imaging: Development, Characterization, and Radiolabeling Studies

Abstract

Lactoferrin, an iron binding glycoprotein-based nanoparticle, has emerged as a promising platform for drug delivery and imaging. This study presents the potential use of the protein nanocarrier in tracking sentinel lymph nodes for cancer staging. Lactoferrin nanoparticles (LF-NPs) were synthesized using a thermal treatment process and optimized to obtain 60-70 nm particle size with PDI less than 0.2. The NPs were characterized microscopically and spectroscopically, ensuring a comprehensive understanding of their physicochemical properties. The LF-NPs were found to be stable in different pH conditions. Their biocompatibility was confirmed through cytotoxicity assessments on RAW 264.7 cells, and hemolysis assay and in vivo toxicity study reveal their safe profile. Additionally, LF-NPs were successfully radiolabeled with technetium-99m (>90% labeling yield). Cell uptake studies with RAW 264.7 exhibited an uptake of ∼6%. Biodistribution studies in Wistar rats shed light on their in vivo behavior and suitability for targeted drug delivery systems. These findings collectively emphasize the multifaceted utility of LF-NPs, positioning them as a promising platform for diverse biomedical innovations.

Figure 1

Effect of different salts on particle size, PDI, and zeta potential of LF-NPs.

Figure 2

Spectral and thermal characterization of LF-NP: (A) FTIR spectra, (B) DSC plot, (C) Raman plot, and (D) XRD diffractogram.

Figure 3

Characterization and stability evaluation of LF-NPs. (A) Concentration of LF-NPs from NTA plot, microscopic characterization of LF-NPs; (B) FESEM, (C) TEM, and stability of LF-NPs in (D) aqueous buffers of different pHs and (E) lyophilized samples stored at different temperatures.

Figure 4

Hemocompatibility study of LF-NPs. (A) Hemolysis activity; microscopic images of RBCs treated with (B) PBS and (C) LF-NPs.

Figure 5

(A) Cytotoxicity evaluation of LF-NPs on RAW 264.7 cells. (B) Body weight changes of Wistar rats treated for acute toxicity study. All values are expressed as mean ± standard deviation, n = 3.

Figure 6

Serum biochemical parameters of Wistar rats treated for the acute toxicity study. All values are expressed as mean ± standard deviation, n = 3.

Figure 7

Histopathological images of major organs after treatment with LF-NPs.

Figure 8

Radiolabeling of LF-NPs and its evaluation. (A) ITLC profiles comparing ^99mTc-labeling of LF-NP in PBS and sodium acetate buffer, (B) effect of incubation time, (C) effect of SnCl₂ on the radiolabeling yield of ^99mTc-LF-NP, (D) PD-10 elution profile, and (E) cellular uptake studies of ^99mTc-LF-NP in RAW 264.7. All values are expressed as mean ± standard deviation, n = 3.