In Vitro Cytotoxicity Of Folate-Silica-Gold Nanorods On Mouse Acute Lymphoblastic Leukemia And Spermatogonial Cells

Objective The purpose of this study was to evaluate in vitro cytotoxicity of gold nanorods (GNRs) on the viability of spermatogonial cells (SSCs) and mouse acute lymphoblastic leukemia cells (EL4s). Materials And Methods In this experimental study, SSCs were isolated from the neonate mice, following enzymatic digestion and differential plating. GNRs were synthesized, then modified by silica and finally conjugated with folic acid to form F-Si-GNRs. Different doses of F-Si-GNRs (25, 50, 75, 100, 125 and 140 µM) were used on SSCs and EL4s. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) proliferation assay was performed to examine the GNRs toxicity. Flow cytometry was used to confirm the identity of the EL4s and SSCs. Also, the identity and functionality of SSCs were determined by the expression of specific spermatogonial genes and transplantation into recipient testes. Apoptosis was determined by flow cytometry using an annexin V/propidium iodide (PI) kit. Results Flow cytometry showed that SSCs and EL4s were positive for Plzf and H-2kb, respectively. The viability percentage of SSCs and EL4s that were treated with 25, 50, 75, 100, 125 and 140 µM of F-Si-GNRs was 65.33 ± 3.51%, 60 ± 3.6%, 51.33 ± 3.51%, 49 ± 3%, 30.66 ± 2.08% and 16.33 ± 2.51% for SSCs and 57.66 ± 0.57%, 54.66 ± 1.5%, 39.66 ± 1.52%, 12.33 ± 2.51%, 10 ± 1% and 5.66 ± 1.15% for EL4s respectively. The results of the MTT assay indicated that 100 µM is the optimal dose to reach the highest and lowest level of cell death in EL4s and in SSCs, respectively. Conclusion Cell death increased with increasing concentrations of F-Si-GNRs. Following utilization of F-Si-GNRs, there was a significant difference in the extent of apoptosis between cancer cells and SSCs

A Comparative Study of Two Folate-Conjugated Gold Nanoparticles for Cancer Nanotechnology Applications

We report a comparative study of synthesis, characteristics and in vitro tests of two folate-conjugated gold nanoparticles (AuNP) differing in linkers and AuNP sizes for selective targeting of folate-receptor positive cancerous cells. The linkers chosen were 4-aminothiophenol (4Atp) and 6-mercapto-1-hexanol (MH) with nanoconjugate products named Folate-4Atp-AuNP and Folate-MH-AuNP. We report the folate-receptor tissue distribution and its endocytosis for targeted nanotechnology. Comparison of the two nanoconjugates’ syntheses and characterization is also reported, including materials and methods of synthesis, UV-visible absorption spectroscopic measurements, Fourier Transform Infra Red (FTIR) measurements, Transmission electron microscopy (TEM) images and size distributions, X-ray diffraction data, elemental analyses and chemical stability comparison. In addition to the analytical characterization of the nanoconjugates, the cell lethality was measured in HeLa (high level of folate receptor expression) and MCF-7 (low level of folate receptor expression) cells. The nanoconjugates themselves, as well as the intense pulsed light (IPL) were not harmful to cell viability. However, upon stimulation of the folate targeted nanoconjugates with the IPL, ~98% cell killing was found in HeLa cells and only ~9% in MCF-7 cells after four hours incubation with the nanoconjugate. This demonstrates that folate targeting is effective in selecting for specific cell populations. Considering the various comparisons made, we conclude that Folate-4Atp-AuNP is superior to Folate-MH-AuNP for cancer therapy

A Comparative Study of Two Folate-Conjugated Gold Nanoparticles for Cancer Nanotechnology Applications

We report a comparative study of synthesis, characteristics and in vitro tests of two folate-conjugated gold nanoparticles (AuNP) differing in linkers and AuNP sizes for selective targeting of folate-receptor positive cancerous cells. The linkers chosen were 4-aminothiophenol (4Atp) and 6-mercapto-1-hexanol (MH) with nanoconjugate products named Folate-4Atp-AuNP and Folate-MH-AuNP. We report the folate-receptor tissue distribution and its endocytosis for targeted nanotechnology. Comparison of the two nanoconjugates’ syntheses and characterization is also reported, including materials and methods of synthesis, UV-visible absorption spectroscopic measurements, Fourier Transform Infra Red (FTIR) measurements, Transmission electron microscopy (TEM) images and size distributions, X-ray diffraction data, elemental analyses and chemical stability comparison. In addition to the analytical characterization of the nanoconjugates, the cell lethality was measured in HeLa (high level of folate receptor expression) and MCF-7 (low level of folate receptor expression) cells. The nanoconjugates themselves, as well as the intense pulsed light (IPL) were not harmful to cell viability. However, upon stimulation of the folate targeted nanoconjugates with the IPL, ~98% cell killing was found in HeLa cells and only ~9% in MCF-7 cells after four hours incubation with the nanoconjugate. This demonstrates that folate targeting is effective in selecting for specific cell populations. Considering the various comparisons made, we conclude that Folate-4Atp-AuNP is superior to Folate-MH-AuNP for cancer therapy

Structural and optical characterization of folate-conjugated gold-nanoparticles

Gold nanoparticles (AuNPs) represent a novel nanomaterials applied in various nanotechnology fields because of their special optical properties. On the other hand, folic acid and folate can be used for selective targeting of nanoparticles towards cancer cells. Folate conjugated AuNPs can be considered as an effective nanoconjugate in the field of nanotargeted photothermal therapy of cancer. In the present work, we report our synthesis of a new nanoconjugate composed of folate, AuNP and 4-aminothiophenol (4Atp) as the linker and named Folate-4Atp-AuNP. The results of our investigations on properties of this new nanoconjugate are presented here including the effects of addition of folate and 4Atp to AuNP on its structural and optical properties. We studied the structural characteristics of Folate-4Atp-AuNP using X-ray diffraction. In addition, we determined its optical band gap energy (1.365 eV), its optical constants using Kramers-Kronig analysis and we identified its metallic face-centered cubic (fcc) lattice structure and particular crystal planes. Our findings indicate that the presence of 4Atp and folate in Folate-4Atp-AuNP had no significant effect on its optical band gap energy. However, some appreciable changes in its optical constants were observed due to the presence of 4Atp and folate in nanoconjugate. The significant changes in optical constants values are apparently as a result of the presence of some special bonds and a few particular functional groups in the nanoconjugate. © 2009 Elsevier B.V. All rights reserved

Fast dynamic MPI cytometry

We developed in vivo fast dynamic MPI “cytometry” to quantify and localize the accumulation of SPIO-labeled stem cells in different organs after intra-arterial injection on a time scale of minutes. Bone marrow-derived mesenchymal stem cells (MSCs) and superoxide dismutase 1 gene-corrected neural precursor cells (NPCs) were labeled with Resovist and injected into Rag2 mice using four separate injections. Whole body standard 2D/3D MPI scans were obtained, quantified and co-registered with CT. Using cell calibration fiducials, cells could be clearly visualized and quantified by MPI in vivo in the brain, liver, and lung. The cytometric ratio of the number of cells in the liver/lung vs. the brain was 1.5 for MSCs and 15.6 for NPCs, respectively, at 24 min post-injection. Fast dynamic MPI cytometry may find applications for optimizing the dose, volume, speed and route of administration when performing interventional cell therapy procedures in real-time

Versatile superparamagnetic radiopaque nanocomplex for in vivo MPI, MRI, and CT stem cell tracking

There are currently over 800 registered clinical trials that use mesenchymal stem cells (MSCs) for tissue repair and immunomodulation. However, the fate of MSCs in vivo including their overall biodistribution and local tissue quantities is not fully known, especially how these parameters change over time. Multi-modal imaging techniques that can track cell therapeutics may allow facilitation and optimization of clinical translation therapeutic outcome. We developed a novel superparamagnetic radiopaque nanocomplex, Albumin-Bi2S3-SPIO (ABS), for labeling of MSCs. ABS exhibited excellent in MPI, MRI, and CT imaging properties, allowing tri-modal imaging use a single nanoplatform