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Modified Gadonanotubes as a promising novel MRI contrasting agent.

Jahanbakhsh R, Atyabi F, Shanehsazzadeh S, Sobhani Z, Adeli M, Dinarvand R - Daru (2013)

Bottom Line: Transmission electron microscopy (TEM) images clearly showed formation of PEGylated CNTs.MRI analysis showed that the prepared solution represents 10% more signal intensity even in half concentration of Gd3+ in comparison with commerciality available contrasting agent Magnevist®.In addition hydrophilic layer of PEG at the surface of CNTs could prepare stealth nanoparticles to escape RES.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 14174, Iran. atyabifa@tums.ac.ir.

ABSTRACT

Background and purpose of the study: Carbon nanotubes (CNTs) are emerging drug and imaging carrier systems which show significant versatility. One of the extraordinary characteristics of CNTs as Magnetic Resonance Imaging (MRI) contrasting agent is the extremely large proton relaxivities when loaded with gadolinium ion (Gdn3+) clusters.

Methods: In this study equated Gdn3+ clusters were loaded in the sidewall defects of oxidized multiwalled (MW) CNTs. The amount of loaded gadolinium ion into the MWCNTs was quantified by inductively coupled plasma (ICP) method. To improve water solubility and biocompatibility of the system, the complexes were functionalized using diamine-terminated oligomeric poly (ethylene glycol) via a thermal reaction method.

Results: Gdn3+ loaded PEGylated oxidized CNTs (Gdn3+@CNTs-PEG) is freely soluble in water and stable in phosphate buffer saline having particle size of about 200 nm. Transmission electron microscopy (TEM) images clearly showed formation of PEGylated CNTs. MRI analysis showed that the prepared solution represents 10% more signal intensity even in half concentration of Gd3+ in comparison with commerciality available contrasting agent Magnevist®. In addition hydrophilic layer of PEG at the surface of CNTs could prepare stealth nanoparticles to escape RES.

Conclusion: It was shown that Gdn3+@CNTs-PEG was capable to accumulate in tumors through enhanced permeability and retention effect. Moreover this system has a potential for early detection of diseases or tumors at the initial stages.

No MeSH data available.


Related in: MedlinePlus

1/T2 values at different Gd3+ concentrations. The line slope represents the r1 value.
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Figure 7: 1/T2 values at different Gd3+ concentrations. The line slope represents the r1 value.

Mentions: Gdn3+@CNTs-PEG clearly caused a significant decrease in both T1 and T2 relaxation time compared with Magnevist®. As shown in Table 1, the T1 values at the same concentration of Gd3+ in the Gdn3+@CNTs-PEG and Magnevist® were 190.7 msec and 405.4 msec, respectively. If we depicted the 1/T1 value at different Gd3+ concentration the r1 value will be obtained 26.6 (mMol-1.sec-1) as shown in Figure 7, while other studies show that the r1 value for Magnevist® was only 13.4 (mMol-1.sec-1) [22].


Modified Gadonanotubes as a promising novel MRI contrasting agent.

Jahanbakhsh R, Atyabi F, Shanehsazzadeh S, Sobhani Z, Adeli M, Dinarvand R - Daru (2013)

1/T2 values at different Gd3+ concentrations. The line slope represents the r1 value.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3716729&req=5

Figure 7: 1/T2 values at different Gd3+ concentrations. The line slope represents the r1 value.
Mentions: Gdn3+@CNTs-PEG clearly caused a significant decrease in both T1 and T2 relaxation time compared with Magnevist®. As shown in Table 1, the T1 values at the same concentration of Gd3+ in the Gdn3+@CNTs-PEG and Magnevist® were 190.7 msec and 405.4 msec, respectively. If we depicted the 1/T1 value at different Gd3+ concentration the r1 value will be obtained 26.6 (mMol-1.sec-1) as shown in Figure 7, while other studies show that the r1 value for Magnevist® was only 13.4 (mMol-1.sec-1) [22].

Bottom Line: Transmission electron microscopy (TEM) images clearly showed formation of PEGylated CNTs.MRI analysis showed that the prepared solution represents 10% more signal intensity even in half concentration of Gd3+ in comparison with commerciality available contrasting agent Magnevist®.In addition hydrophilic layer of PEG at the surface of CNTs could prepare stealth nanoparticles to escape RES.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 14174, Iran. atyabifa@tums.ac.ir.

ABSTRACT

Background and purpose of the study: Carbon nanotubes (CNTs) are emerging drug and imaging carrier systems which show significant versatility. One of the extraordinary characteristics of CNTs as Magnetic Resonance Imaging (MRI) contrasting agent is the extremely large proton relaxivities when loaded with gadolinium ion (Gdn3+) clusters.

Methods: In this study equated Gdn3+ clusters were loaded in the sidewall defects of oxidized multiwalled (MW) CNTs. The amount of loaded gadolinium ion into the MWCNTs was quantified by inductively coupled plasma (ICP) method. To improve water solubility and biocompatibility of the system, the complexes were functionalized using diamine-terminated oligomeric poly (ethylene glycol) via a thermal reaction method.

Results: Gdn3+ loaded PEGylated oxidized CNTs (Gdn3+@CNTs-PEG) is freely soluble in water and stable in phosphate buffer saline having particle size of about 200 nm. Transmission electron microscopy (TEM) images clearly showed formation of PEGylated CNTs. MRI analysis showed that the prepared solution represents 10% more signal intensity even in half concentration of Gd3+ in comparison with commerciality available contrasting agent Magnevist®. In addition hydrophilic layer of PEG at the surface of CNTs could prepare stealth nanoparticles to escape RES.

Conclusion: It was shown that Gdn3+@CNTs-PEG was capable to accumulate in tumors through enhanced permeability and retention effect. Moreover this system has a potential for early detection of diseases or tumors at the initial stages.

No MeSH data available.


Related in: MedlinePlus