We discuss several prospective plasmonic platforms based on nanostructured or heterostructured metamaterials for ultrasensitive label-free optical biosensing. We show how atomic 2D materials, plasmonic surface lattice resonances and topologically dark metamaterials can improve significantly the detection limit of small bio-objects such as viruses, small DNA sequences, vitamins, drugs, etc. resulting in a fast, inexpensive, sensitive sensors ready for usage at the point-of-care or the point-of-action.