Application of paramagnetically tagged molecules for magnetic resonance imaging of biofilm mass transport processes.
Application of paramagnetically tagged molecules for magnetic resonance imaging of biofilm mass transport processes.
复制标题
顺磁标记分子在生物膜传质过程磁共振成像中的应用。
DOI：
10.1128/aem.03016-09
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发表时间：
2010
影响因子：
4.4
通讯作者：
Ramanan B
中科院分区：
文献类型：
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作者：
Ramanan B
当用顺磁性标签标记时，分子通过磁共振成像（MRI）变得容易可见。因此，MRI可用于成像它们通过多孔介质的运输。在这项研究中，我们证明了这种方法可以应用于图像的质量传输过程中的生物膜。钆和二亚乙基三胺五乙酸（Gd-DTPA），一种市售的顺磁性分子的复合物的运输，在琼脂（作为一个均匀的测试系统）和在光养生物膜成像。所收集的图像是T1加权的，其中T1是生物膜的MRI特性并且依赖于Gd-DTPA浓度。一个校准协议被应用到convertT 1参数地图到浓度地图，从而揭示了空间分辨浓度的示踪剂在不同的时间间隔。将琼脂实验获得的数据与一维扩散模型的数据进行比较，发现Gd-DTPA在琼脂中的传输完全是通过扩散进行的，扩散系数为7.2 × 10− 10 m2 s −1。相比之下，光养生物膜实验的数据与二维扩散模型的数据比较显示，生物膜内Gd-DTPA的运输是通过扩散和平流进行的，相当于1.04 × 10− 9 m2 s −1的扩散系数。该技术可用于进一步探索生物膜中的质量传递过程，无论是通过使用广泛的市售顺磁性标记分子和纳米颗粒，还是通过使用定制的标记分子。
Molecules become readily visible by magnetic resonance imaging (MRI) when labeled with a paramagnetic tag. Consequently, MRI can be used to image their transport through porous media. In this study, we demonstrated that this method could be applied to image mass transport processes in biofilms. The transport of a complex of gadolinium and diethylenetriamine pentaacetic acid (Gd-DTPA), a commercially available paramagnetic molecule, was imaged both in agar (as a homogeneous test system) and in a phototrophic biofilm. The images collected wereT1weighted, whereT1is an MRI property of the biofilm and is dependent on Gd-DTPA concentration. A calibration protocol was applied to convertT1parameter maps into concentration maps, thus revealing the spatially resolved concentrations of this tracer at different time intervals. Comparing the data obtained from the agar experiment with data from a one-dimensional diffusion model revealed that transport of Gd-DTPA in agar was purely via diffusion, with a diffusion coefficient of 7.2 × 10−10m2s−1. In contrast, comparison of data from the phototrophic biofilm experiment with data from a two-dimensional diffusion model revealed that transport of Gd-DTPA inside the biofilm was by both diffusion and advection, equivalent to a diffusion coefficient of 1.04 × 10−9m2s−1. This technology can be used to further explore mass transport processes in biofilms, either by using the wide range of commercially available paramagnetically tagged molecules and nanoparticles or by using bespoke tagged molecules.