Spermidine hydrochloride can combine with metal salts such as copper chloride to form the corresponding copper amine complex, and can react with acyl chloride to form three amide bonds. In addition, spermidine can also coordinate with metal ions, such as silver ions and platinum ions.

Spermidine hydrochloride can inhibit neuronal NO synthase (nNOS), bind to and precipitate DNA; it can also be used to purify DNA binding proteins and stimulate T4 polynucleotide kinase activity; it also has a good anti-aging effect, can also prevent the occurrence of Alzheimer's disease, and can protect nerves.