Meet Indigo

The Indigo system is designed to enable ice-free, freeze-free immunization outreach. The system ensures vaccines stay at a safe temperature—between 2 and 8 °C—throughout five days of continuous operation, even in the harshest environments. The Indigo system presents opportunities to extend capabilities of vaccinators and to immunize children in the most hard-to-reach communities.

The Indigo system has a unique set of features and capabilities that address the limitations of traditional ice-based carriers:

Extended cooling: Provides vaccine-safe storage temperatures for five days of continuous use at 10 to 43 °C ambient temperature, without external power.
Freeze-free: Prevents vaccine exposure to freezing temperatures without action from the user.
On/off switch: The five-day cold life of a charged vaccine carrier may be stored until needed.
Safe: Contains no harmful materials or refrigerants.
Portable: Transportable by car, motorcycle, or on foot.
Reusable and durable with two year warranty.

Cooler

The cooler is a 1.7L container with integrated ColdLoop® evaporative cooling technology. Vaccines are stored in the cooler’s inner chamber during outreach. The cooler will maintain a 2-8 °C inner temperature for five days in ambient temperatures as high as 43 °C.

Cooler Lid

The cooler lid provides access to the vaccine chamber while insulating the opening. The display reports chamber temperature and remaining cold life. It also alerts users to temperature variations outside the 2-8 °C range, lid openings, and low batteries. The cooler lid even records temperature and alarm data.

The outer lid remains in place during outreach, along with the monitoring tools and temperature probe. It can stay in place at all times except during charging. The inner lid allows easy access to vaccines without removing key components of the monitoring tools.

A simple, well-insulated design makes accessing the interior simple. An easy-to-read display and alerts to temperature excursions keep vaccinators aware of status.

Cold Key

The cold key is used to turn the cooler on or off. When the cold key is magnetically affixed to its dock, the tube connecting the outer ceramic desiccant ring to the inner absorbent layer opens with an audible click, allowing the ColdLoop® technology to cool the vaccine chamber. When the cold key is removed, the connecting tube closes, the cooling process stops, and the remaining cooling power is reserved for later use.

The cold key is tethered to the cooler lid to ensure it is not lost.

A magnetic on/off switch for the cooling power of ColdLoop.

Charger

A “charge” is not electrical in the context of the Indigo system. Instead, a charge refers to the movement of water: the Indigo charger applies heat to precise areas of the cooler to restore its cooling capacity.

More specifically, the charger drives water from the cooler’s outer ceramic desiccant ring to the absorbent layer surrounding the vaccine chamber. Once the water has traveled to the inner layer, switching the cooler on allows the evaporative cooling process to draw it back to the outer ring, which brings the vaccine chamber to the desired 2-8 °C temperature.

The charge cycle takes about four hours. The cooler lid is connected to the charger during this process to update the cold life count and to log the charging event.

The Indigo charger is engineered to perform in the most challenging power environments. An operating range from 110VAC to 278VAC creates adaptability across infrastructures, while a suite of voltage stabilization features protects against damage and underperformance.

A single charger supports multiple vaccine carriers. Changes in geography, fuel cost, and staff costs can drive the optimal carrier:charger ratio for a specific deployment as low as 4:1 or as high as 20:1.

Restores ColdLoop’s cooling power for vaccine carriers throughout a region. A single charger typically supports about 10 vaccine carriers.

Bag

The bag protects the cooler and lid during any drops and impacts that may occur during demanding journeys, while enabling the device to be worn comfortably on a user’s back. The upper zipper provides easy access to the vaccine chamber and monitoring tools. The lower zipper allows the cooler to be removed for charging. Pockets on the front and top are designed to hold vaccine records and foam disks for vials.

A durable, comfortable, utilitarian carrying solution.

ColdLoop® Technology

Cold key is attached to dock, activating ColdLoop
Water is drawn to the outer layer as vapor, cooling the vaccine chamber, while vacuum insulation minimizes heat transfer from the surrounding environment
The charging process heats the outer layer, moving water vapor back to the inner sorbent ring and restoring ColdLoop’s cooling capacity

ColdLoop is a self-contained evaporative cooling system driven by the movement of water between an absorbent layer surrounding the vaccine chamber and a highly adsorbent ceramic desiccant layer surrounding the cooler. The inner and outer layers are connected by a tube and sealed at low pressure along with an optimized amount of water. Users and technicians are not required to add water at any point, as water does not leave the system during operation.

The extremely adsorptive nature of the ceramic desiccant draws the water back to the outer ring as vapor. The water draws heat from its surroundings as it evaporates, and this energy moves to the outer layer; hence this process cools the vaccine chamber.

A thermostat, permanently set at the ideal point during manufacture, monitors the vaccine chamber and temporarily suspends the cooling process at 4 °C by closing the connecting tube. The monitor opens the tube to re-start cooling when the temperature begins to rise.