Table 3.
Representative molecules of medical interest determined with laser-based spectroscopic methods in near- and mid-infrared regions
| Molecule | λ (µm) | Detection method | Detection limit (measurement time) | Human tests/in vitro/application is breath, otherwise specified |
|---|---|---|---|---|
| Acetaldehyde | 5.79 | TDLAS/WMS | 80 ppb (5 s) | After alcoholic beverage [97] |
| Acetone | ~ 8.2 | ICOS | 170 ppb (0.2 s) | [98] |
| ~ 3.3 | ICOS | 100 ppb (0.4 s) | [99] | |
| ~ 3.3 | TDLAS + multipass cell | 14 ppb (15 min) | Diabetes [100] | |
| 1.69 | CEAS | ~ 160 ppb | [101, 102] | |
| ~ 8.2 | TDLAS + multipass cell | 150 ppb | Diabetes [103] | |
| ~ 8.2 | ICOS | 30 ppb (30 s) | [104] | |
| Acetylene | 1.52 | CRDS | 175 ppt (10 min) | After smoking [105] |
| 1.53 | ICOS | 1.5 ppb (128 s) | After smoking [106] | |
| Ammonia | ~ 3 | CRDS | 0.3 ppb (30 s) | Breath and skin [107, 108], during hemodialysis [109] |
| 9.56 | PAS | 100 ppb (3 s) | Hemodialysis [110] | |
| 9.56 | QEPAS | 10 ppb (1 s) | [111], Exercise [112] | |
| 3.04 | PAS | 1 ppm (10 s) | Bacteria [70] | |
| 10.3 | CRDS | 50 ppb (20 s) | [113] | |
| 10.3 | TDLAS + multipass cell | 3 ppb (10 s) | [114] | |
| 9.07 | WMS + multipass cell | 7 ppb (5 s) | [115] | |
| 1.51 | CE-OFCS | 4 ppm (30 s) | [76] | |
| Carbon dioxide (isotopes) | 1.60 | CRDS | 3 ppm (3 ms) | [116] |
| 1.60 | CE-OFCS | < 10 ppm (30 s) | [76] | |
| 2.05 | ICOS | ± 0.15‰ precision for δ13DOB 13C‰ | H. pylori infection [117, 118] | |
| ~ 2 | ICAS | ~ 100 ppb | [119] | |
| Carbon monoxide | 4.57 | TDLAS + multipass cell | 0.8 ppb (1 s) | Asthma, COPD [34] |
| 4.59 | TDLAS + multipass cell | 14 ppb (60 s) | [120] | |
| 4.72 | WMS + multipass cell | 0.6 ppb (15 s) | Smoking [36] | |
| 4.61 | ICOS/WMS | 7 ppb (1 s) | [38] | |
| 2.33 | OF-CEAS | 1 ppb (0.3 s) | [46] | |
| 1.6 | CE-OFCS | 0.9 ppm (0.3 s) | [76] | |
| Carbon monoxide (isotopes) | 4.69 | WMS + multipass cell | 0.6 ppb (10 s) | [39] |
| Carbonyl sulfide | 4.86 | TDLAS + multipass cell | 1.2 ppb (0.4 s) | [121] |
| 4.90 | CRDS | 7 ppt (1 s) | [122] | |
| Ethane | 3.35 | ICOS | 0.48 ppb (1 s) | [123] |
| 3.34 | ICOS | 50 ppt (0.25 s) | [99] | |
| 3.34 | TDLAS/WMS + multipass cell | 70 ppt (1 s) | Dialysis [40, 124, 125] | |
| ~ 3.4 | CRDS | 0.5 ppb (0.8 s) | [126] | |
| ~ 3.4 | TDLAS + multipass cell | 70 ppt (0.7 s) | [127], Lung cancer [128] | |
| 3.34 | CRDS | 270 ppt (1 s) | [129] | |
| Ethylene | 10.5 | PAS | 0.3 ppb (5 s) | Cardiac surgery [67], Endotoxemia [130], skin [66] |
| 10.5 | PAS | 100 ppb | Renal failure [131] | |
| Glucose | ~ 9 | PAS | ~ 30 mg/dL (in blood) | Skin [62] |
| Hydrogen cyanide | 1.54 | CRDS | 0.3 ppb (2.5 min) | Breath, skin [132], Oral fluid [133] |
| 3.04 | PAS | 0.4 ppb (10 s) | [69], in vitro [70] | |
| Methane | 1.65 | PAS | 0.3 ppm (12 s) | [134] |
| 2.33 | OF-CEAS | 25 ppb (0.3 s) | [46] | |
| ~ 3.3 | CRDS | 1–10 ppb (120 s) | [135] | |
| Nitric oxide | 5.23 | ICOS + WMS | 2 ppb (15 s) | [136] |
| 5.22 | TDLAS + multipass cell | 2 ppb (1 s) | [137] | |
| 5.22 | TDLAS + multipass cell | 1.5 ppb (4 s) | [138] | |
| 5.26 | TDLAS + multipass cell | 0.5 ppb (1 s) | Asthma, COPD [34], Septic shock [139] | |
| 5.22 | ICOS | 0.4 ppb (1 s) | [140] | |
| 5.2 | ICOS | 0.7 ppb (1 s) | Breath and skin [141] | |
| Nitric oxide (isotopes) | 5.33 | CRDS | 7 ppt (70 s) | [142] |
| 5.43 | Faraday rotation spectroscopy | 0.5–4 ppb (1 s) | Breath, blood, urine [143] | |
| Nitrous oxide | 4.57 | TDLAS + multipass cell | 0.8 ppb (1 s) | Asthma, COPD [34] |