Yes. It's recommended that you use your personal github account for work.
On their help page Merging multiple user accounts:
If you have separate accounts for work and personal use, you can merge the accounts.
Tip: We recommend using only one user account to manage both personal and professional repositories.
On their help page Can I create accounts for people in my organization?:
While you can add users to an organization you've created, you can't create personal user accounts on behalf of another person.
Because you access an organization by logging in to a personal account, each of your team members needs a personal account. Once you have user names for each person you'd like to add to your organization, you can add them to teams.
It works.