Housing Unit for SiN Chip Vitrification – Team 1

Overview

With the invention of silicon nitride (SiN) chips to be used in cryo-EM for studying the 3-D structure of proteins, it became necessary for an update to the current vitrification system for the sample preparation. Currently, the most common verification device used is the Vitrobot, which essentially flash-freezes samples of proteins onto copper chips so that the 3-D structure of the proteins can be preserved and seen under an electron microscope. The current vitrification process involves a blotting mechanism that previously introduced experimental error into the sample preparation process by causing uneven icing of the sample. The new SiN chips do not require blotting excess sample from the chip before freezing. Our task was to create a new housing unit that can remove the blotting mechanism to vitrify the SiN chips for cryo-EM use. We created blueprints for a housing unit to be assembled out of aluminum 80/20 T-bars and acrylic, but with the occurrence of COVID-19, we developed a 3-D printed prototype with the appropriate accommodations for future project integrations.

Objectives

-Design a housing unit that has holes for entry and exit of a plunging mechanism, entry holes for pipetting sample onto SiN chip, and integration accommodations for the humidifying system.

-Manufacture the housing unit

-Work with the Humidifier team keep the unit at 90% humidity

-Test the humidity and design of the housing unit

Approach

– Gathered the needs of the new vitrification housing unit from our sponsor

– Conducted training on the current Vitrobot device to further understand the demands of the vitrification device and to collect the necessary dimensions for our new housing unit prototype

-Researched the best materials to use for the framing of the unit and the transparent sides in terms of acrylic, plastic, polycarbonate, and aluminum

-Generated an initial virtual prototype using 80/20 materials and acrylic side paneling in Solidworks

-Reoriented our prototype to be 3-D printed with plastic due to the impact of COVID-19

-Planned integration and testing with the humidifying team to ensure that 90% humidity could be maintained in our prototype

Outcomes

– Delivered the 3-D printed prototype to our sponsor with instructions on further integration and assembly

-Delivered the 80/20 Solidworks prototype plans to our sponsor for potential future use

-Planned testing of our project in conjunction with the humidifying team and future iterations for the design of the housing unit