Li Yunchao, Wang Zhen, Ou Lily M L, Yu Hua-Zhong
Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
Anal Chem. 2007 Jan 15;79(2):426-33. doi: 10.1021/ac061134j.
A mild and efficient surface activation protocol to convert polycarbonate (PC) substrates, e.g., plastic bases of compact disks, to biochip platforms for DNA probe immobilization and target detection is described. The preparation procedure (activation, patterning, and coupling) is simple and effective; the on-chip hybridization is sensitive and selective. Particularly, UV/ozone treatment of PC sheets produces a hydrophilic surface with a high density of reactive carboxylic acid groups [(4.8 +/- 0.2) x 10-10 mol/cm2] in less than 10 min at ambient conditions, and no significant aging or physical damage to the substrate is observed. Covalent immobilization of DNA probes via both passive (reagent-less photopatterning and coupling in bulk solution phase) and flow-through (creation of microarrays with microfluidic channel plates) procedures has been demonstrated. Subsequent hybridization shows uniform and strong fluorescent signals for complementary target DNA and allows clear discrimination between fully complementary targets and strands with a single base-pair mismatch. The surface chemistry described herein will facilitate the development of disposable plastic biochips (not limited to DNA microarrays) and the fabrication of biomedical devices that are readable with conventional optical drives.
本文描述了一种温和且高效的表面活化方案，用于将聚碳酸酯（PC）基材（如光盘的塑料基底）转化为用于DNA探针固定和靶标检测的生物芯片平台。制备过程（活化、图案化和偶联）简单有效；芯片上的杂交灵敏且具有选择性。特别地，在环境条件下，对PC片材进行紫外线/臭氧处理可在不到10分钟内产生具有高密度反应性羧酸基团[（4.8±0.2）×10-10 mol/cm2]的亲水性表面，且未观察到基材有明显老化或物理损伤。已证明通过被动（无试剂光图案化和在本体溶液相中偶联）和流通（使用微流体通道板创建微阵列）程序均可实现DNA探针的共价固定。随后的杂交显示出针对互补靶标DNA的均匀且强烈的荧光信号，并能够清晰区分完全互补的靶标和具有单个碱基对错配的链。本文所述的表面化学将有助于一次性塑料生物芯片（不限于DNA微阵列）的开发以及可通过传统光驱读取的生物医学设备的制造。
