Converting Microsoft SQL Server collation to UTF 8
Encoding? Do you mean collation? The collation only affects things like equality tests, sort order, etc. They don't affect the allowed encodings for column values.

If you want to store unicode text, you should make sure your columns are among


NCHAR
NVARCHAR
NTEXT (2-byte characters)


rather than


CHAR
VARCHAR
TEXT (1-byte characters).