Note 6 — Intangible Assets

Intangible assets, net consisted of the following:

At December 31, 2020 and 2019, the Company had capitalized approximately $270,000 and $335,224, respectively, for costs related to patents that have not been awarded. During the years ended December 31, 2020 and 2019, the Company wrote-off $20,660 and $14,707, respectively, in previously capitalized patent costs.

Amortization expense amounted to $98,035 and $79,536 for the years ended December 31, 2020 and 2019, respectively. Amortization expense for the succeeding five years and thereafter is $94,532 (2021‑2025) and $826,244 (thereafter).