A novel CT contrast agent for intestinal-targeted imaging through rectal administration

Jingyao Zhu,Shichen Xie,Hao Weng,Jun Zhu,Jiejun Cheng

doi:10.1515/epoly-2021-0076

Jingyao Zhu, Shichen Xie + Show 3 more

Open Access

https://doi.org/10.1515/epoly-2021-0076

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Abstract

Abstract In this study, a novel CT contrast agent used by rectal administration is developed for targeting intestinal imaging. Iopamidol, an iodinated contrast agent, is loaded in chitosan (CS) nanospheres modified by Anti-5-HT3R (AH) antibody. The obtained AH-CS-I nanospheres (AH-CS-I Ns) would combine to 5-HT3 receptors highly expressed on the gastrointestinal mucosal, enhancing the intestinal-targeting ability of the contrast agent. The AH-CS-I Ns were administered by the rectal route for intestinal CT imaging, and FITC-labeled AH-CS-I Ns were prepared for investigating the in vivo distribution of the contrast agent. As a result, obvious contrast enhancement could still be observed at 6 h post administration because of the poorly absorption of enteral AH-CS-I Ns. Unlike the intravascularly administered agents, AH-CS-I Ns would not accumulate in the kidney and induce adverse reactions. Therefore, this technology has potential applications in the examination of intestinal diseases and could reduce the side effect of commercial iopamidol.

Highlights

In this study, a novel computed tomography (CT) contrast agent used by rectal administration is developed for targeting intestinal imaging
The morphology of CS-I Ns has not changed much compared to chitosan nanospheres (CS Ns) (Figure 2b), suggesting that iopamidol was successfully encapsulated into the chitosan shells
The carboxyl groups in the antibody are exposed to ethylcarbodiimide hydrochloride (EDC)/N-hydroxy succinimide (NHS), and reactive NHS esters are formed, when a primary amine group on the surface of CS Ns comes in contact with the ester, a covalent bond is formed. These results suggest that AH-CS-I Ns with a positive potential value and stabile structure were prepared, and the positive charge of chitosan molecules and Anti-5-HT3R antibody modification strongly contribute to its intestinal-targeted properties for use in intestinal imaging

Summary

Introduction

Abstract: In this study, a novel CT contrast agent used by rectal administration is developed for targeting intestinal imaging. The obtained AH-CS-I nanospheres (AH-CS-I Ns) would combine to 5-HT3 receptors highly expressed on the gastrointestinal mucosal, enhancing the intestinal-targeting ability of the contrast agent. Obvious contrast enhancement could still be observed at 6 h post administration because of the poorly absorption of enteral AH-CS-I Ns. Unlike the intravascularly administered agents, AH-CS-I Ns would not accumulate in the kidney and induce adverse reactions. Unlike the intravascularly administered agents, AH-CS-I Ns would not accumulate in the kidney and induce adverse reactions This technology has potential applications in the examination of intestinal diseases and could reduce the side effect of commercial iopamidol

Methods

Results

Conclusion