Can I use this IC as reference for a clamping circuit. Would it be able to sink or clamp any amount of current even if its a small percentage of
Kindly advise me on the same.
You can also use ADR441 and ADR431, this has the MSOP package option and still pin to pin compatible with ADR421.
The ADR421 is not designed/specs to sink current. But we also have ADR4525 which can sink and source current up to 10mA.