Li Ying-Chang, Chang Ying-Feng, Su Li-Chen, Chou Chien
Department of Optics and Photonics, National Central University, Jhongli, Taiwan, 320.
Anal Chem. 2008 Jul 15;80(14):5590-5. doi: 10.1021/ac800598c. Epub 2008 May 29.
In this paper, a novel differential-phase-sensitive surface plasmon resonance biosensor (DP-SPRB) is proposed and developed, in which a two-frequency laser is integrated with a differential amplifier in order to analytically convert the phase modulation into amplitude modulation. With the use of the conventional envelope detection technique, the differential phase is precisely decoded in real time in terms of the demodulated amplitude. In order to verify high detection sensitivity of the DP-SPRB, a sucrose-water solution and glycerin-water solution at low concentrations were both tested, and the experimental results confirm that the detection sensitivity on wt % concentration of the sucrose solution is 0.00001%. Moreover, the real-time monitoring mouse IgG/antimouse IgG interaction shows the minimum concentration of mouse IgG to be at 10 fg/mL. To our knowledge, this is the highest sensitivity ever measured by a surface plasmon resonance biosensor. However, because of the limited dynamic range of DP-SPRB, it can only apply to biomolecule interactions at extremely low concentration.
本文提出并研制了一种新型的差分相位敏感表面等离子体共振生物传感器（DP-SPRB），其中将双频激光器与差分放大器集成，以便将相位调制解析转换为幅度调制。通过使用传统的包络检测技术，根据解调后的幅度实时精确解码差分相位。为了验证DP-SPRB的高检测灵敏度，对低浓度的蔗糖水溶液和甘油水溶液进行了测试，实验结果证实，蔗糖溶液重量百分比浓度的检测灵敏度为0.00001%。此外，实时监测小鼠IgG/抗小鼠IgG相互作用表明，小鼠IgG的最低浓度为10 fg/mL。据我们所知，这是表面等离子体共振生物传感器所测得的最高灵敏度。然而，由于DP-SPRB的动态范围有限，它仅适用于极低浓度下的生物分子相互作用。
