Microarrays are key platforms for biomolecule detection owing to their parallelizability and amenability for high-throughput. However, conventional fluorescent microarrays still suffer from low specificity and sensitivity, therefore are unsuitable for detection of low abundance nucleic acids. In this study, we demonstrate a universal microarray platform with high specificity and ultra-sensitivity for fluorescent detection of DNA and micro RNA (miRNA), which employs a DNA tetrahedral structured probe (DTSP) together with a hybridization chain reaction (HCR) based signal amplification technique. By precisely modulating the number of base pairs on each tetrahedron side, we developed three different sized DTSPs: 17 base pairs, 26 base pairs, and 37 base pairs (DTSP-17, DTSP-26 and DTSP-37, respectively). A low detection limit of 10 aM was obtained by DTSP-26, notably much lower than detection limits of prior methods. Furthermore, our microarray platform can distinguish single base DNA mismatches and thus exhibits single nucleotide specificity. Lastly, our microarray platform can be implemented for miRNA detection, as we demonstrate in a mimic medium, demonstrating potential for its use in clinical diagnosis.

微阵列由于其可并行性和高通量的适用性而成为生物分子检测的关键平台。然而，常规的荧光微阵列仍具有低的特异性和灵敏度，因此不适用于检测低丰度的核酸。在这项研究中，我们展示了具有高特异性和超灵敏性的通用微阵列平台，可用于DNA和微RNA（miRNA）的荧光检测，该平台采用DNA四面体结构探针（DTSP）以及基于杂交链反应（HCR）的信号扩增技术。通过精确调制每个四面体侧的碱基对数目，我们开发了三种不同大小的DTSP：17个碱基对，26个碱基对和37个碱基对（分别为DTSP-17，DTSP-26和DTSP-37）。DTSP-26获得的低检测限为10 aM，明显低于现有方法的检测限。此外，我们的微阵列平台可以区分单碱基DNA错配，因此表现出单核苷酸特异性。最后，我们的微阵列平台可用于miRNA检测，正如我们在模拟培养基中展示的那样，证明了其在临床诊断中的潜力。