Well, there are infinite lines perpendicular to a curve at any single point. However, there's one that I would consider "special", and that would be the one from the point on the curve to the center of the osculating circle that describes the curvature at that point.
For any infinite line, I'd take the tangent vector, use the PlaneFromNormal component, the pick any point on that plane, do a Change Basis transformation, and create a line.
For the "special" line, I'd use the curvature component and use the curvature vector to make a line.