Glucose, also known as dextrose, serves as the monomer for larger carbohydrates such as starch and cellulose.

Commercial glucose is obtained by hydrolyzing starch through boiling it with dilute H₂SO₄ at 393 K under pressure. Starch serves as the raw material for this process.

Glucose can be prepared from sucrose by boiling it with dilute HCl or H₂SO₄ in alcoholic solution. The products obtained are equal amounts of glucose and fructose through the hydrolysis of sucrose.

Monosaccharides are classified into aldoses (containing an aldehyde group) and ketoses (containing a keto group). Aldoses have an aldehyde group, while ketoses have a keto group.

Glucose is found freely in nature and in combined forms. It is present in sweet fruits, honey, and ripe grapes, where it occurs in large amounts.