It isn't illegal to chew gum, but it is illegal to bring them into Singapore or sell them except for medical purposes. Since you can't buy gum (selling is illegal) there's no way to chew them so it's almost as good as not being able to chew gum. See this: http://www.customs.gov.sg/leftNa...
Definition: In Vitro. A study done in vitro, in contrast, looks at how a drug or procedure responds in the confines of a test tube or laboratory dish. Clinical trials or medical studies may be performed either in vivo or in vitro.
The Vitros 350 chemistry system gets the job done right the first time. Up to 40 samples can be placed into one of four trays which can accommodate any size primary collection tube or sample cup. The sample volume for the Vitros micro slide assays is very small (between 5-11 micro liters).