How to add space (" ") and single quote ("'") to email validate function?

I use 
System.Text.RegularExpressions.Regex("\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*")
to do RegularExpressions checking for valid email address.
How to add space (" ") and single quote ("'") to the string "(\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*)" to validate as well?