Quantifying 64 drugs, illicit substances, and D- and L- isomers in human oral fluid with liquid-liquid extraction
Table 5. Dilution study
| Drug / Metabolite | 1:5 Dilution | 1:10 Dilution | 1:20 Dilution | 1: 50 Dilution |
| 6-MAM | -0.16 | 4.57 | 7.30 | 18.55 |
| 7-Amino Clonazepam | -36.28 | 6.40 | 38.67 | 53.62 |
| Alprazolam | 2.18 | 4.06 | 6.52 | 14.43 |
| Amitriptyline | -1.67 | -2.67 | 5.22 | 5.53 |
| Amphetamine | 1.03 | 4.04 | 9.45 | 12.00 |
| a-OH Alprazolam | 5.90 | -2.30 | 2.44 | 2.89 |
| Benzoylecgonine | -5.43 | 1.31 | 8.61 | 8.54 |
| Buprenorphine | -6.65 | -14.20 | 2.54 | -0.63 |
| Carisoprodol | -11.43 | -4.02 | 13.36 | 11.79 |
| Chlordiazepoxide | -19.90 | -19.40 | -18.54 | -15.39 |
| Clonazepam | 5.46 | 4.05 | 19.52 | 37.10 |
| Codeine | 17.35 | -3.71 | 14.86 | 11.43 |
| Cotinine | -5.45 | 0.83 | 2.74 | 5.43 |
| Cyclobenzaprine | -2.94 | 2.76 | 5.31 | 6.05 |
| Desalkylflurazepam | 9.80 | 14.02 | 19.80 | 38.83 |
| Desipramine | -0.64 | 6.75 | 9.89 | 18.24 |
| Diazepam | -6.73 | 1.28 | 11.79 | 11.53 |
| Dihydrocodeine | -0.35 | 17.71 | 16.90 | 1.06 |
| Doxepin | -8.03 | -0.39 | 0.35 | 0.33 |
| EDDP | -3.36 | 1.50 | 10.73 | 7.68 |
| Fentanyl | 1.10 | 4.63 | 10.09 | 8.80 |
| Fluoxetine | -7.13 | 4.62 | 16.67 | 6.59 |
| Gabapentin | -2.80 | 9.41 | -7.22 | 14.08 |
| Hydrocodone | 2.28 | 7.31 | -4.46 | -5.21 |
| Hydromorphone | -1.26 | 4.34 | -1.52 | 3.21 |
| Imipramine | -1.69 | 5.93 | 0.61 | 7.07 |
| Ketamine* | -19.27 | -11.18 | 7.96 | 9.94 |
| Lorazepam | 8.57 | 3.42 | 0.57 | 12.08 |
| MDA | -0.64 | 9.12 | 10.55 | 3.46 |
| MDMA | -1.71 | 5.78 | 12.68 | 11.55 |
| MDPV | -0.90 | 1.54 | 5.01 | 7.49 |
| Meperidine | -13.29 | -6.57 | 4.29 | 3.09 |
| Meprobamate | -9.67 | -5.32 | 4.19 | 10.96 |
| Methadone | -10.62 | -6.74 | 1.05 | 10.66 |
| Methamphetamine | -8.17 | -0.32 | 3.13 | 0.66 |
| Methylphenidate | -10.14 | 2.33 | 12.03 | 10.16 |
| Morphine | -4.01 | 6.04 | 12.40 | -5.21 |
| Naloxone | -8.69 | -8.42 | 2.11 | 4.82 |
| Naltrexone | -9.13 | -7.98 | -1.48 | -10.93 |
| Nicotine | -15.97 | -3.19 | 6.03 | 11.19 |
| Norbuprenorphine | -0.81 | 3.18 | 3.58 | 2.05 |
| Nordiazepam | 9.56 | 7.98 | 13.45 | 11.26 |
| Norfentanyl | 7.91 | 3.21 | 15.30 | -9.30 |
| Norhydrocodone | 1.74 | -11.65 | 2.28 | 12.83 |
| Norketamine | -0.22 | 9.12 | 12.49 | 8.15 |
| Noroxycodone | -5.03 | 1.66 | 4.82 | -3.80 |
| Noroxymorphone | 5.26 | 9.62 | 1.51 | 1.76 |
| Nortriptyline | -7.43 | -0.14 | 13.26 | -1.04 |
| O-desmethyl Tramadol | -4.43 | -8.07 | 0.72 | -3.05 |
| Oxazepam | 19.47 | 7.29 | 23.86 | 42.76 |
| Oxycodone | 1.20 | -8.02 | -3.54 | -13.84 |
| Oxymorphone | -2.77 | -0.28 | 11.92 | -1.13 |
| Paroxetine | -0.71 | 3.11 | 11.10 | 11.24 |
| Phencyclidine | -0.42 | 8.96 | 11.32 | 16.31 |
| Pregabalin | 14.26 | -15.73 | 11.47 | 4.97 |
| Ritalinic Acid | -10.16 | -3.28 | 1.11 | 2.24 |
| Tapentadol | 0.23 | 6.90 | 11.11 | 14.75 |
| Temazepam | 58.41 | 17.55 | 166.96 | 224.88 |
| Tramadol | 4.37 | 2.03 | 1.03 | -1.49 |
| Venlafaxine | -10.77 | -3.33 | -0.19 | 1.64 |
| Zaleplon | -6.99 | -0.31 | 7.43 | 12.99 |
| Zolpidem | -4.15 | 1.43 | 5.19 | 14.15 |
| Zopiclone | -4.34 | 4.16 | 8.36 | 10.70 |
| THC-COOH | 8.33 | 19.53 | -8.44 | 7.74 |
| D-Amphetamine | 2.38 | 5.97 | 9.87 | 12.19 |
| L-Amphetamine | 2.56 | 7.39 | 10.81 | 9.60 |
| D-Methamphetamine | -0.51 | -3.58 | -1.77 | -3.63 |
| L-Methamphetamine | 3.89 | 1.00 | 5.46 | 3.87 |
Note: All analytes based at a 1:10 dilution. Percent difference from expected with a 4000 ng/mL standard diluted as indicated.