ACHE and Parkinsonism: For example, the AChE enzyme immobilized by physical adsorption onto different surfaces (i.e., silica sol-gel incorporating gold nanoparticles (AuNPs-Si-SG), platinum-coated with AChE) was used for clinical applications of therapeutic drugs (donepezil, rivastigmine, huperzine, galantamine) or in screening and testing for neurological diseases (e.g., Parkinson’s and Alzheimer’s) [33,34,35,36,37].