youtube give b12 injection How to a Vitamin in the Arm - Easy Guide π HOW TO SELF-INJECT B12
Description
Why Sublingual B12 Tablets: - Enhanced Absorption
It has a molecular weight of approximately 403.9 Da in its free peptide form (or ~340.4 Da without the copper ion)

PMID 10448529

But heres some research: Photolysis of Vitamin B12 The rate of destruction of crystalline vitamin B PHOTOLYSIS OF VITAMIN B 12 in neutral aqueous solutions, when exposed to direct sunlight, indirect sunlight, dim daylight, artificial light, ultraviolet light, and various monochromatic light sources has been determined

PMID 29216732
A longitudinal study confirmed that homocysteine-lowering B Vitamins slow the rate of brain atrophy in old people with mild cognitive impairment
