Incubation Chamber

Lore & Background

The earliest incubators were invented thousands of years ago in ancient Egypt and China, where they were used to keep chicken eggs warm. In the 16th century, Jean Baptiste Porta drew on ancient Egyptian design to create a more modern egg incubator. Rene-Antoine Ferchault de Reaumur took up the challenge in the middle of the 17th century, warming his incubator with a wood stove and monitoring its temperature using the Reaumur thermometer. In the 19th century, researchers began to experiment with bell jars containing a single lit candle. The first infant incubator, used at a women's hospital in Paris, was heated by kerosene lamps. Fifty years later, Julius H. Hess designed an electric infant incubator. In the 1960s, the CO2 incubator was introduced to the market.

In Their Own Story

In the 1960s, the CO2 incubator was introduced to the market when doctors realized they could use it to identify and study pathogens found in patients' bodily fluids. A sample was harvested, placed onto a sterile dish, and into the incubator. The air was kept at 37 degrees Celsius, the same temperature as the human body, and the incubator maintained the atmospheric carbon dioxide and nitrogen levels necessary to promote cell growth. At this time, incubators also began to be used in genetic engineering, allowing scientists to create biologically essential proteins such as insulin. Genetic modification could now take place on a molecular level, helping to improve the nutritional content and resistance to pestilence and disease of fruits and vegetables.

Reader's Guide

An incubator is made up of a chamber with a regulated temperature. Some incubators also regulate humidity, gas composition, or ventilation. The simplest incubators are insulated boxes with an adjustable heater, typically going up to 60 to 65 °C, though some can go slightly higher (generally to no more than 100 °C). The most commonly used temperature for bacteria such as E. coli and for mammalian cells is approximately 37 °C. For the budding yeast Saccharomyces cerevisiae, a growth temperature of 30 °C is optimal. More elaborate incubators can include the ability to lower the temperature, or to control humidity or CO2 levels. For mammalian cells, relative humidity is typically >80% and a CO2 level of 5% is maintained. Incubators generally maintain a constant temperature; additional features include humidity control, shaking for mixing, gas regulation, air circulation, and redundant power sources. Sizes range from tabletop models to warm rooms.

Did You Know?

• The earliest incubators were used in ancient Egypt and China to hatch chicken eggs.
• The CO2 incubator was introduced to the market in the 1960s.
• The most commonly used temperature for both E. coli and mammalian cells is approximately 37 °C.
• The first infant incubator was heated by kerosene lamps.