albumin - publications

Predict more albumin - ligand interactions now!


1. Phys Med Biol. 2012 Apr 18;57(9):2787-2802. [Epub ahead of print]

Paramagnetic perfluorocarbon-filled albumin-(Gd-DTPA) microbubbles for the
induction of focused-ultrasound-induced blood-brain barrier opening and
concurrent MR and ultrasound imaging.

Liao AH, Liu HL, Su CH, Hua MY, Yang HW, Weng YT, Hsu PH, Huang SM, Wu SY, Wang
HE, Yen TC, Li PC.

Graduate Institute of Biomedical Engineering, National Taiwan University of
Science and Technology, Taipei, Taiwan, ROC. Graduate Institute of Biomedical
Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan, ROC.

This paper presents new albumin-shelled Gd-DTPA microbubbles (MBs) that can
concurrently serve as a dual-modality contrast agent for ultrasound (US) imaging
and magnetic resonance (MR) imaging to assist blood-brain barrier (BBB) opening
and detect intracerebral hemorrhage (ICH) during focused ultrasound brain drug
delivery. Perfluorocarbon-filled albumin-(Gd-DTPA) MBs were prepared with a mean
diameter of 2320 nm and concentration of 2.903×10(9) MBs ml(-1) using
albumin-(Gd-DTPA) and by sonication with perfluorocarbon (C(3)F(8)) gas. The
albumin-(Gd-DTPA) MBs were then centrifuged and the procedure was repeated until
the free Gd(3+) ions were eliminated (which were detected by the xylenol orange
sodium salt solution). The albumin-(Gd-DTPA) MBs were also characterized and
evaluated both in vitro and in vivo by US and MR imaging. Focused US was used
with the albumin-(Gd-DTPA) MBs to induce disruption of the BBB in 18 rats. BBB
disruption was confirmed with contrast-enhanced T(1)-weighted turbo-spin-echo
sequence MR imaging. Heavy T(2)*-weighted 3D fast low-angle shot sequence MR
imaging was used to detect ICH. In vitro US imaging experiments showed that
albumin-(Gd-DTPA) MBs can significantly enhance the US contrast in T(1)-, T(2)-
and T(2)*-weighted MR images. The r(1) and r(2) relaxivities for Gd-DTPA were
7.69 and 21.35 s(-1)mM(-1), respectively, indicating that the MBs represent a
positive contrast agent in T(1)-weighted images. In vivo MR imaging experiments
on 18 rats showed that focused US combined with albumin-(Gd-DTPA) MBs can be used
to both induce disruption of the BBB and detect ICH. To compare the signal
intensity change between pure BBB opening and BBB opening accompanying ICH,
albumin-(Gd-DTPA) MB imaging can provide a ratio of 5.14 with significant
difference (p = 0.026), whereas Gd-DTPA imaging only provides a ratio of 2.13 and
without significant difference (p = 0.108). The results indicate that
albumin-(Gd-DTPA) MBs have potential as a US/MR dual-modality contrast agent for
BBB opening and differentiating focused-US-induced BBB opening from ICH, and can
monitor the focused ultrasound brain drug delivery process.

PMID: 22510713 [PubMed - as supplied by publisher]