本研究的目的為發展DNA壓電感測器並應用於Mycobacterium tuberculosis序列的檢測。首先以不同碳鏈長度的含硫化合物修飾壓電晶體金電極表面，結果顯示以長碳鏈的16-Mercaptohexadecanoic acid (16-MHDA)處理，所形成的感測表面有較佳的表現。而後，卵白素(avidin)經由共價結合於感測表面上，生物素(biotin)修飾的探針則藉由avidin-bioin之間的作用，穩定的固定於晶片上。試驗結果顯示，在高離子強度的反應條件下，有利於探針固定化的進行。與目標序列的雜合反應顯示，本研究提出的DNA壓電感測器可專一的檢測目標序列，在濃度為0.5-7.5 μg/mL之間有線性。感測表面再生試驗的結果顯示，以0.5 M HCl重複清洗感測表面三次，可以將目標股洗下，並且能成功的再與目標股反應，達到重複檢測的目的。
In this paper, a DNA biosensor was designed by means of immobilization of a single stranded DNA probe on a piezoelectric transducer surface to recognize specifically Mycobacterium tuberculosis complementary target DNA sequence. First, alkanethiols with different carbon lengths were used to modify sensor surface. The result showed that sensing surface modified with 16-Mercaptohexadecanoic acid gave the better performance. Subsequently, avidin was covalently bound to the surface and a biotinylated probe was immobilized through avidin-biotin interaction onto the surface. It was observed that probe immobilization was achieved in a condition with higher ionic strength. The proposed DNA piezoelectric sensor demonstrated the specific hybridization with complementary target sequence and a linear relationship was observed when the probe concentrations are 0.5~7.5 μg/mL. Washing the sensing surface with 0.5 M HCl three times appeared to be a better regeneration method and the sensing surface can be reused for the next measurement.
