the surface preparation is need to attach any kind of molecule. you have perfect surface means you can binding more amount of molecules. but i didnt know about the bio molecules. normally SS surface was protected by thin film of CrO3, But eventually the interaction was based on the physical manner only.

Thank you very much for your answer. Actually, I'd like to avoid any kind of interaction. I'd like to inject my sample using a hamilton syringe. I know already that borosilicate glass doesn't absorb DNA.

About the SS of the needle, I know that SS can inhibit microfluidic PCR reactions but no clue about the reason (whether is the enzyme or the DNA template to get absorbed).