Ion mediated monolayer deposition of gold nanoparticles on microorganisms: discrimination by age.
Ion mediated monolayer deposition of gold nanoparticles on microorganisms: discrimination by age.
复制标题
DOI：
10.1021/la9021195
复制
发表时间：
2010-01
期刊：
影响因子：
--
通讯作者：
V. Maheshwari;D. Fomenko;Gaurav Singh;R. Saraf
中科院分区：
文献类型：
--
作者：
V. Maheshwari;D. Fomenko;Gaurav Singh;R. Saraf
通过纳米颗粒靶向细胞进行药物输送、成像或诊断的一般策略涉及探针与颗粒上和细胞表面上的目标分子之间的免疫特异性结合。通常，分子的大分子性质需要特定的构象才能实现所需的免疫特异性，并且颗粒沉积的程度受到细胞上存在的受体分子数量的限制。在本报告中，我们通过用简单离子（例如Ca(2+)）装饰纳米颗粒，成功获得了靶向结合，而不影响细胞的活力。正如赖氨酸包被的金纳米粒子所证实的那样，用于研究的酵母细胞酿酒酵母对正电荷没有特定的静电亲和力。发现纳米颗粒结合的特异性与酵母细胞的代谢活力直接相关（即，与较老的细胞相比，新陈代谢更高的年轻一代发生明显更大的沉积）。离子介导的靶向沉积似乎是生物学重要离子的普遍现象，如 Mg(2+) 和（有毒）Cd(2+) 之间的对比所证明的那样。由于细胞表面有大量离子受体，（渗透）纳米颗粒以单层形式沉积在细胞上的高密度，被证明是构建生物电子设备的潜在方法。使用离子作为靶细胞的界面可以在诊断疾病和使用活细胞制造生物传感器方面具有潜在的应用。
A general strategy to target cells by nanoparticles for drug delivery, imaging, or diagnostics involves immunospecific binding between the probes and target molecules on the particles and on the cell surface, respectively. Usually, the macromolecular nature of the molecules requires a specific conformation to achieve the desired immunospecificity, and the extent of deposition of particles is limited by the number of receptor molecules present on the cell. In this report, we successfully obtain targeted binding by decorating the nanoparticle with simple ions, such as Ca(2+), without affecting the cell's vitality. The yeast cells for study, Saccharomyces cerevisiae, have no specific electrostatic affinity toward positive charge as confirmed by lysine-coated Au nanoparticles. The specificity of nanoparticle binding is found to be directly related to the metabolic vitality of the yeast cell (i.e., a significantly larger deposition occurs on a younger generation with higher metabolism than on older cells). The ion-mediated targeted deposition seems to be a general phenomenon for biologically important ions, as demonstrated by the contrast between Mg(2+) and (toxic) Cd(2+). The high density of (percolating) nanoparticle deposition as a monolayer on the cells, as a result of the large number of ion receptors on the cell surface, is shown to be a potential method for building bioelectronic devices. The use of ions as an interface to target cells can have possible applications in diagnosing diseases and making biosensors using live cells.