Bio-reactors are the cooking pots of biochemists and bio-technologists, in which pharmaceutical agents, enzymes or nematodes are produced for the purpose of biological pest control. A nutrient solution (such as heat, oxygen, acid or alkali) is used to regulate the pH value and the desired product is formed. The more optimal the conditions are, the greater the yield will be. Researchers have now developed spherical probes to more effectively monitor and streamline the manufacturing process.