“Crystallization of colloidal microparticles with precise temperature control”
The optical-scale growth of colloidal crystals not only provides a model system for crystallization but also is a major thrust of nanotechnology research. To grow colloidal crystals, a chamber of DNA-coated colloids is heated above the melting temperature to cause the colloids to separate and then cooled to a temperature slightly below the melting temperature. We present an automated crystallization machine that takes an uncrystallized chamber of DNA-coated colloids and provides a steady set temperature for crystallization while taking periodic pictures. The major component of this crystallization machine is a customizable temperature controller. This further requires a Peltier heating element, temperature-sensing thermistor, and code to interface with these components. Our final iteration utilizes a water-block to remove excess heat and provide further stability to the temperature-controlling system. The current design allows for future improvements such as an autonomous system that can adjust the steady set-temperature based on a crystal-recognition software.