Dear sir i can understand your concern. in my opinion there are good brand of insulin which are more effective and good quality everyone manufactures insulin by same process but the cold chain management matters a lot in deciding the efficacy of insulin. In my opinion Brands like Novo Nordisk and Eli lilly are very old and pioneers But with out knowing the diagnosis and physiological condition of your wife its difficult to comment on insulin. for diabetes Exercise and diet also matters a lot. Best Regards. Dr Vamsi Krishna Consultant Diabetologist Apollo Hospitals