<p>PEG-coated and Gd-loaded fluorescent silica nanoparticles for targeted prostate cancer magnetic resonance imaging and fluorescence imaging</p>

Abstract

Background: Multimodal imaging probes have become a powerful tool for improving detection sensitivity and accuracy, which are important in disease diagnosis and treatment. Methods: In this study, novel bifunctional magnetic resonance imaging (MRI)/fluorescence probes were prepared by loading gadodiamide into fluorescent silica nanoparticles (NPs) (Gd@Cy5.5@SiO 2 -PEG-Ab NPs) for targeting of prostate cancer (PCa). The physicochemical characteristics, biosafety and PCa cell targeting ability of the Gd@Cy5.5@SiO 2 -PEG-Ab NPs were studied in vitro and in vivo. Results: The Gd@Cy5.5@SiO 2 -PEG-Ab NPs had a spherical morphology with a relatively uniform size distribution and demonstrated high efficiency for Gd loading. In vitro and in vivo cell-targeting experiments demonstrated a high potential for the synthesized NPs to target prostate-specific membrane antigen (PSMA) receptor-positive PCa cells, enabling MRI and fluorescence imaging. In vitro cytotoxicity assays and in vivo hematological and pathological assays showed that the prepared NPs exhibited good biological safety. Conclusion: Our study demonstrates that the synthesized Gd@Cy5.5@SiO 2 -PEG-Ab NPs have great potential as MRI/fluorescence contrast agents for specific identification of PSMA receptor-positive PCa cells.

Gadolinium-Coated Mesoporous Silica Nanoparticle for Magnetic Resonance Imaging

“…Dynamic light scattering (DLS) curves (Figure 1D) revealed that the average diameter of the NPs was 162.50 nm, suggesting that the DLS measured these NPs as slightly larger than the TEM, which might be the result of the rehydration of the NPs in the aqueous solution used for the DLS evaluation. As expected, the zeta potential of the MSN was negative (Figure 1E), whereas the moderate size of these particles should help avoid renal clearance and uptake to the reticuloendothelial system (RES) in the liver, which were both essential for increasing circulation time (Phillps et al, 2010;Koo et al, 2011;Shao et al, 2011;O'Connell et al, 2017;Jiang et al, 2019). The EDS (Figure 2B) spectrum confirmed that the red circle appearing in Figure 2A indicates Gd-existence with an atomic fraction of 0.91% (atom.%) Gd (Table 1).…”

“…These spectra also included a peak at 1,636 cm −1 , corresponding to the bending vibration of -OH. Taken together, these patterns were representative of the characteristic absorption peaks of MSN materials (Figure 5) (Ni et al, 2016;He et al, 2019;Jiang et al, 2019;Cai et al, 2020).…”

Recent Advances and Implication of Bioengineered Nanomaterials in Cancer Theranostics

“…Therefore, to avoid the accumulation of proteins in the blood serum that lead to endocytosis and improve the circulation time of nanoparticles, PEG has been used. Gd@Cy5.5@SiO2 nanoparticles were prepared in conjugation with the antibody YPSMA-1 against prostate-specific membrane antigen (PSMA) to improve the target specificity of prostate cancer imaging material [120]. PSMA is a transmembrane protein of type II that is specifically present in prostate cancer cells with high uniformity and frequency and some other normal tissues.…”

“…Therefore, it is an ideal targeting agent for the imaging and treatment of prostate cancer. PEG-coated and Gd-loaded targeted fluorescent silica nanoparticles were synthesized by reverse microemulsion and carbodiimide method [120]. The biosafety and targeting ability of the nanoparticles was confirmed by in vivo and in vitro studies.…”

<p>New Oral Coaxial Nanofibers for Gadodiamide-Prospective Intestinal Magnetic Resonance Imaging and Theranostic</p>

“…60 Also, the cytotoxicity of PEG-coated and Gdloaded fluorescent silica NPs using LNCaP and PC3 Cells was studied by Jiang et al They found no significant cytotoxicity after 24 h of incubation with NPs, suggesting that these NPs exhibited no toxicity toward LNCaP and PC3 cells. 61 Nörenberg et al examined the potential gadolinium (Gd) accumulation in the brain of healthy mice after long-term oral administration of Gd-containing food pellets and investigated whether Gd could lead to adverse central nervous system (CNS) effects. They suggested that low levels of intracerebral Gd do not lead to detectable CNS effects, and in particular did not impair locomotor abilities in the healthy murine model, even over a very long exposure time.…”