Electrochemical method for monitoring the progress of polymerase chain reactions using Methylene blue as an indicator

We report on the proof-of-principle of an amperometric method to monitor the progress of a polymerase chain reaction (PCR) in real-time. It is based on the finding that the intercalating redox probe Methylene Blue (MB) becomes less easily electrochemically detectable once intercalated into double-stranded DNA (ds-DNA) compared to its free form. This was studied by cyclic voltammetry before and after addition of salmon sperm ds-DNA. Under optimized conditions, the products of the PCR of mitochondrial DNA fragments were quantitatively detected at different stages of amplification cycles. This strategy is potentially cheaper and easier to integrate into a hand-held miniaturized device than fluorescence-based real-time PCR.

乙醇在Ni-ZnO-ZrO2-YSZ阳极SOFC上的发电性能

为考察乙醇用于固体氧化物燃料电池的可行性,用柠檬酸溶胶 凝胶制备阳极催化材料Ni-ZnO-ZrO₂,利用机械混合法制备Ni-ZnO-ZrO₂-YSZ(Y₂O₃稳定的ZrO₂)阳极。用涂覆法,在YSZ电解质上,制备了Ni-ZnO-ZrO₂-YSZ/YSZ/LSM（La_0.85Sr_0.15MnO₃）与Ni-YSZ/YSZ/LSM的单体电池。在不同蒸发器操作温度、电池操作温度和乙醇蒸气流量下,以乙醇为燃料进行发电实验,对两种阳极的电池发电性能进行比较。实验结束后,用SEM检测了两种电池阳极的表面。结果表明,Ni-ZnO-ZrO₂-YSZ阳极SOFC的电池输出性能明显高于Ni-YSZ阳极,且Ni-ZnO-ZrO₂-YSZ阳极具有较好的抗积炭能力。