Note 4 — Intangible Assets

Intangible assets, net consisted of the following:

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At December 31, 2021 and 2020, the Company had capitalized $306,640 and $270,000, respectively, for costs related to patents that have not been awarded. During the years ended December 31, 2021 and 2020, the Company wrote-off $528 and $20,660, respectively, in previously capitalized patent costs.

Amortization expense amounted to $132,330 and $98,035 for the years ended December 31, 2021 and 2020, respectively. Amortization expense for the succeeding five years and thereafter is $147,249 (2022-2026) and $1,012,765 (thereafter).