Dermatological Application of PAMAM – Vitamin Bioconjugates and Host-Guest Complexes – Vitamin C Case Study

Stoichiometry of reaction describes the quantitative relationships among substances as they participate in chemical reactions. Furthermore the term stoichiometry is used to describe the quantitative relationship among elements in compounds. This is also valid in the quantitative description of so-called weak complexes formed between molecules through non-covalent and non-ionic interactions. They generally arise from hydrogen bonding or Van der Waals interactions and are very common in biological chemistry, like in the case of enzyme-substrate, enzyme-inhibitor, or enzyme-coenzyme complexes. In less specific systems, stoichiometry may be referred to the number of small molecules interacting with one macromolecule to form complex structure. Depending on the interaction type between the components of the complex they are often desribed as host (macromolecule, H) – guest (small molecule, g) complexes. The host-guest complexes can sometimes be isolated as compounds of defined strochiometry, however their dissolution always leads to establishing an equilibrium between complexes and free guest, according to the scheme: