@mikewick77: Potassium Citrate

It has various physical appearances, including a brick-red powder, a vitreous black solid, and a grey metallic-looking form. It seldom occurs in this elemental state or as pure ore compounds in Earth's crust.

Selenium is found in metal sulfide ores, where it substitutes for sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores.

is Selenium doing something with Potassium & Sulfur?

Flipping Anion & Cation?

Anti-Structure
Potassium Sulfate

anti-structure, called the antifluorite structure, anions and cations are swapped.

Selenium belongs to the category of redox nonmetals. Selenium is included in the same class with sulfur metalloids, which implies that selenium should be able to substitute for sulfur in biological complexes. As a congener of sulfur, selenium becomes part of a protein's structure as selenocysteine and selenomethionine, not as a selenium atom ligated directly to the protein as a prosthetic group. The former are the active cofactors in selenium enzymes.

The biological significance of Se is predominantly dependent on its incorporation into the selenocysteine (Sec) for synthesis of selenoproteins (SePs), such as thioredoxin reductase family enzymes and glutathione peroxidase family enzymes.

Methane, arsenic, selenium and the origins of the DMSO reductase family

https://www.nature.com/articles/s41598-020-67892-9

N-Acetyl-l-cysteine Enhances the Effect of Selenium Nanoparticles on Cancer Cytotoxicity by Increasing the Production of Selenium-Induced Reactive Oxygen Species

https://pmc.ncbi.nlm.nih.gov/articles/PMC7254790/

https://www.sciencedirect.com/topics/medicine-and-dentistry/selenium-ion

Rubidium and potassium levels are altered in Alzheimer’s disease brain and blood but not in cerebrospinal fluid

https://pmc.ncbi.nlm.nih.gov/articles/PMC5109650/

The increased potassium intake improves cognitive performance and attenuates histopathological markers in a model of Alzheimer's disease

https://www.sciencedirect.com/science/article/pii/S0925443915002811

Epidermal Barrier
NHE1
Sodium-Proton Antiporter
Stratum Corneum
Corneodesmosome
Corneocyte
Lamellae
Filaggrin (FLG)
Ceramide

Serine Protease (SP)
Acidifying

Sodium-Calcium Exchanger

Potassium-Dependent Sodium-Calcium Exchanger

Calcium-Activated Potassium Channel

Paroxysmal Depolarizing Shift