Non-invasive tracking of stem cells after transplant is necessary for cell therapy and tissue engineering field. Herein, we introduce natural and biodegradable nanoparticle to develop a highly efficient nanoprobe with the ability to penetrate the stem cell for tracking. Based on the use of (Gd3+) to label stem cells for magnetic resonance imaging (MRI) we synthesized nanoparticle-containing Gd3+. Gd3+ could be used as t1-weighted MRI contrast agents. In this study, chitosan-alginate nanoparticles were synthesized as a clinical Dotarem® carrier for decreased t1-weighted. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FTIR) were utilized for nanoprobe characterization and ICP analysis was performed for Gd3+ concentration measurement. The results illustrate that nanoprobes with spherical shape and with a size of 80 nm without any aggregation were obtained. Relaxivity results suggest that r1 in the phantom was 12.8 mM-1s-1 per Gd3+ ion, which is 3.5 times larger than that for Dotarem® (r1 ∼3.6 mM-1s-1 per Gd3+ ion) and this result for synthesized nanoprobe in stem cells 3.56 mM-1s-1 per Gd3+ ion with 2.16 times larger than that for Dotarem® was reported and also enhanced signal in in-vivo imaging was observed. Chitosan-alginate nanoparticles as a novel biocompatible probe for stem cell tracking can be utilized in tissue engineering approach.

中文翻译：

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天然聚合物纳米颗粒作为间充质干细胞标记的非侵入性探针。

移植后对干细胞进行非侵入式跟踪对于细胞治疗和组织工程领域而言是必需的。在这里，我们介绍天然和可生物降解的纳米粒子，以开发具有穿透干细胞进行跟踪能力的高效纳米探针。基于（Gd3 +）标记干细胞用于磁共振成像（MRI），我们合成了包含纳米粒子的Gd3 +。Gd3 +可用作t1加权MRI造影剂。在这项研究中，壳聚糖-海藻酸钠纳米颗粒被合成为可降低t1加权的临床Dotarem®载体。利用扫描电子显微镜（SEM），透射电子显微镜（TEM），动态光散射（DLS）和傅里叶变换红外光谱（FTIR）进行纳米探针表征，并进行ICP分析进行Gd3 +浓度测量。结果表明获得了具有球形且尺寸为80nm且没有任何聚集的纳米探针。弛豫结果表明，幻影中的r1为12.8 mM-1s-1 / Gd3 +离子，是Dotarem®的r1的3.5倍（r1〜3.6 mM-1s-1 / Gd3 +离子），这是茎中合成纳米探针的结果。据报道，每个Gd3 +离子具有3.56 mM-1s-1的细胞，是Dotarem®的2.16倍，并且还可以观察到体内成像中增强的信号。壳聚糖-藻酸盐纳米颗粒作为一种新型的生物相容性干细胞追踪探针可用于组织工程学方法。比Dotarem®大5倍（每Gd3 +离子r1〜3.6 mM-1s-1），据报道，干细胞中合成纳米探针的结果为每Gd3 +离子3.56 mM-1s-1，比Dotarem®大2.16倍。并在体内成像中观察到增强的信号。壳聚糖-藻酸盐纳米颗粒作为一种新型的生物相容性干细胞追踪探针可用于组织工程学方法。比Dotarem®大5倍（每个Gd3 +离子r1〜3.6 mM-1s-1），据报道，干细胞中合成纳米探针的结果为每个Gd3 +离子3.56 mM-1s-1，比Dotarem®大2.16倍。并在体内成像中观察到增强的信号。壳聚糖-藻酸盐纳米颗粒作为一种新型的生物相容性干细胞追踪探针可用于组织工程学方法。