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α and β-glucose are isomers, which means they have the same molecular formula (C6H12O6) but a slightly different arrangement of atoms. The key difference between α and β-glucose is the position of the hydroxyl group (-OH) on carbon 1 (C1). In α-glucose, the hydroxyl group is below the plane of the ring. In β-glucose, the hydroxyl group is above the plane of the ring.

A glycosidic linkage is formed when two glucose molecules are joined together by a dehydration reaction (removal of water), resulting in a covalent bond called a glycosidic bond. For α-glycosidic linkage: An α-glycosidic bond forms between the α-glucose's C1 carbon (anomeric carbon) and the C4 carbon of another glucose molecule. In the linkage, the α-glucose's C1 hydroxyl group is below the plane of the ring, and the bond between the C1 and C4 forms below the plane of the ring. For β-glycosidic linkage: A β-glycosidic bond forms between the β-glucose's C1 carbon (anomeric carbon) and the C4 carbon of another glucose molecule. In the linkage, the β-glucose's C1 hydroxyl group is above the plane of the ring, and the bond between the C1 and C4 forms above the plane of the ring.

α-linkage: 1. Two α-glucose molecules come in close proximity, with their C1 and C4 hydroxyl groups facing each other. 2. The hydroxyl group on C1 of one α-glucose reacts with the hydroxyl group on C4 of another α-glucose molecule, releasing a water molecule (H2O). 3. The α-glycosidic bond forms below the plane of the ring between the C1 of one glucose molecule and the C4 of the other glucose molecule, creating a disaccharide called maltose. β-linkage: 1. Two β-glucose molecules come in close proximity, with their C1 and C4 hydroxyl groups facing each other. 2. The hydroxyl group on C1 of one β-glucose reacts with the hydroxyl group on C4 of another β-glucose molecule, releasing a water molecule (H2O). 3. The β-glycosidic bond forms above the plane of the ring between the C1 of one glucose molecule and the C4 of the other glucose molecule, creating a disaccharide called cellobiose.