Peking University demonstrate a ALD modified nanochannels for protein sensing

Peking University demonstrate a new type of nanopore device based on ALD Al2O3 modified track-etched conical nanochannels for protein sensing. The conformal Al2O3 film on the conical nanochannels was performed in a homemade flow-through ALD system with TMA and H2O as the precursors at a low deposition temperature of 120 °C to prevent thermal damage to the polymer PET.

Atomic Layer Deposition Modified Track-Etched Conical Nanochannels for Protein Sensing

Ceming Wang, Qibin Fu, Xinwei Wang, Delin Kong, Qian Sheng, Yugang Wang, Qiang Chen, and Jianming Xue

Anal. Chem., Article ASAP
DOI: 10.1021/acs.analchem.5b01501

 

Nanopore-based devices have recently become popular tools to detect biomolecules at the single-molecule level. Unlike the long-chain nucleic acids, protein molecules are still quite challenging to detect, since the protein molecules are much smaller in size and usually travel too fast through the nanopore with poor signal-to-noise ratio of the induced transport signals. In this work, we demonstrate a new type of nanopore device based on atomic layer deposition (ALD) Al2O3 modified track-etched conical nanochannels for protein sensing. These devices show very promising properties of high protein (bovine serum albumin) capture rate with well time-resolved transport signals and excellent signal-to-noise ratio for the transport events. Also, a special mechanism involving transient process of ion redistribution inside the nanochannel is proposed to explain the unusual biphasic waveshapes of the current change induced by the protein transport.