| AVS 62nd International Symposium & Exhibition | |
| Biomaterial Interfaces | Wednesday Sessions |
| Session BI-WeM |
| Session: | Biomolecules at Interfaces |
| Presenter: | Jiachao Yu, Pacific Northwest National Laboratory |
| Authors: | J. Yu, Pacific Northwest National Laboratory Y. Zhou, Pacific Northwest National Laboratory X. Hua, Pacific Northwest National Laboratory Z. Zhu, Pacific Northwest National Laboratory S. Liu, Southeast University, China X.-Y. Yu, Pacific Northwest National Laboratory |
| Correspondent: | Click to Email |
Hydration is crucial to the structure, conformation, and biological activity of proteins. Proteins without water molecules surrounding them would not have viable biological activity. Specifically, water molecules will interact with the surface and internal structure of proteins, and different hydration states of proteins make such interactions distinct. Thus, it is important to understand the hydration of proteins on surfaces, which can provide a fundamental understanding of the mechanism of their structure, conformation, and biological activity. Our group developed an important technique to study liquid surfaces and interfaces, namely System for Analysis at the Liquid Vacuum Interface (SALVI). It has been recently applied to study hydrated protein biofilms. SALVI is a vacuum compatible microfluidic device that consists of a SiN window as the detection area and a microchannel made of polydimethylsiloxane (PDMS). The protein solution was introduced into the microchannel. After incubating for a period of time, a hydrated protein biofilm formed on the back side of the SiN membrane. The information of hydrated proteins was collected using the time-of-flight secondary ion mass spectrometry (ToF-SIMS) in the SALVI device in the liquid state. Compared with previous results from dry protein samples, we not only confirmed the amino acid compositions of proteins, but also firstly discovered that the distribution of water molecules surrounding and inside proteins were varied among different types of proteins. Our liquid ToF-SIMS results show that 1). The water clusters number and relative counts vary among the same hydrated proteins, which imply that the distribution of water molecules surrounding and inside a protein is inhomogeneous; 2). The same water clusters have varied content in different types of proteins, which indicate that the distribution of water molecules have a strong relationship with the structure and conformation of the proteins at the biointerface. These first observations of hydrated protein biofilms on a surface will pave the investigation of the structure, conformation, and biological activity of proteins in the future.