| Mucin-5AC | 585.57 | UniProtKB |
| Mucin-5B | 596.34 | UniProtKB |
| MUFA (Monounsaturated Fatty Acids) | 0.269 | Found via general search |
| Myeloperoxidase (MPO) | 150 | Found via general search |
| Myoglobin | 17 | Found via general search |
| N-Acetylneuraminic Acid-d3 | 0.31229 | UniProtKB |
| Natriuretic peptides A | 16.396 | UniProtKB |
| Nectin-2 | 57.742 | UniProtKB |
| Neopterin | 0.253 | Found via general search |
| Neural cell adhesion molecule 1 | 94.574 | UniProtKB |
