Harnessing X‐Ray Energy‐Dependent Attenuation of Bismuth‐Based Nanoprobes for Accurate Diagnosis of Liver Fibrosis

Abstract

Timely detection of liver fibrosis by X‐ray computed tomography (CT) can prevent its progression to fatal liver diseases. However, it remains quite challenging because conventional CT can only identify the difference in density instead of X‐ray attenuation characteristics. Spectral CT can generate monochromatic imaging to specify X‐ray attenuation characteristics of the scanned matter. Herein, an X‐ray energy‐dependent attenuation strategy originated from bismuth (Bi)‐based nanoprobes (BiF3@PDA@HA) is proposed for the accurate diagnosis of liver fibrosis. Bi element in BiF3@PDA@HA can exhibit characteristic attenuation depending on different levels of X‐ray energy via spectral CT, and that is challenging for conventional CT. In this study, selectively accumulating BiF3@PDA@HA nanoprobes in the hepatic fibrosis areas can significantly elevate CT value for 40 Hounsfield units on 70 keV monochromatic images, successfully differentiating from healthy livers and achieving the diagnosis of liver fibrosis. Furthermore, the enhancement produced by the BiF3@PDA@HA nanoprobes in vivo increases as the monochromatic energy decreases from 70 to 40 keV, optimizing the conspicuity of the diseased areas. As a proof of concept, the strategically designed nanoprobes with energy‐dependent attenuation characteristics not only expand the scope of CT application, but also hold excellent potential for precise imaging‐based disease diagnosis.

High atomic number nanoparticles to enhance spectral CT imaging aspects

“…The image also shows the energy-dependent attenuation of the targeted region after BiF 3 @PDA@HA NPs injection in the in vivo model, and changes in the spectral house units (HU) of the liver and tissue at different energy attenuations. Furthermore, because of the energy-dependent attenuation of Bi, the diseased area could be suitable for selecting different monochromatic energies via spectral CT. 87…”

Biomarker‐Responsive Nanosystems for Chronic Disease Theranostics

“…[246][247][248] Therefore, it is very important to distinguish between the various stages of liver fibrosis as the degree of fibrosis is closely linked with therapeutic decision-making. [249][250][251][252][253] Yang et al developed a protein-based MRI contrast agent (namely ProCA32.collagen1) for quantitatively mapping levels of collagen I in chronic liver A-C) Reproduced with permission. [240] Copyright 2021, American Chemical Society.…”

Polysaccharide-Based Theranostic Systems for Combined Imaging and Cancer Therapy: Recent Advances and Challenges

“…Hyaluronic acid-coated Bi 2 O 3 NPs showed multiple activities by exhibiting efficient attenuation of X-rays along with providing radiosensitization causing cell apoptosis. In this way, the developed system could be a potential candidate for CT imaging guided radiotherapy of tumors due to the low cost of bismuth element as compared to gold and higher radiosensitization. , Similarly, other bismuth-based nanoparticles (such as Bi 2 S 3 NPs and Bi 2 Se 3 nanoplates) and tungsten trioxide NPs are also able to attenuate X-rays with high efficiency. − However, few studies have reported the application of theranostics by combining polysaccharides with bismuth and tungsten-based nanoparticles. ,− due to the lack of functional groups for post-modification and difficulty in controlling their shape and size.…”