I don't understand about the significance of fingerprint analysis at all. It may give result apparently promptly, however MS is not a quantitative detector at all. I think that usual biochemical researchers could not buy the high cost machine of MS, and I also have no MS machine. I think that MS has been given a Nobel prize in 2002, and reports using MS may have been increased without consideration about the determination or quantitative abilities in it's method.
Therefore, I believe that the work to get the result may become slower, but that usual HPLC determination method using UV detector gives the sufficient and reliable result.
Therefore, I would like to express my opinions on the detectors.
I think that the first man who has recognized about the importance of quantitative determination is the third king of the sixth dynasty of Egypt of Pepi I Meryre (reigned 2332 – 2287 BC), who might have improved the balance scale. In east asia, the ancient emperor of Shi Huangdi (Qin dynasty of China; reigned 246 – 221 BC) has also improved and decided the standard for weights and measures; i.e., ① length, zhǐ (ata or shaku in Japanese; the length between an outstretched thumb and middle finger; c.a.18 cm and now 30 cm), span (the length between an outstretched thumb and little finger; c.a. 23 cm), meter, ②volume, sheng (sho in Japanese; Asian unit of volume, approx. 1.8 litres), litre, and ③ weight, gramme, kan (3.75 kg in Japan). In 1875, metric system (International System of Units：Système international d'unités (SI) "À tous les temps, à tous les peuples") has been proposed by France. Recently, unit of pressure has been changed from 1 b (bar) = dyn/cm² = g/(cm·s²) = 0.1 Pa (CGS system) to 1 Pascal (Pa) = 1 kg/(m·s²) =10 b (MKS system), although I like 100 kg/cm² rather than 9.58 MPa and 1423 psi in HPLC.
Spectrophotometer; Beer-Lambert-Bouguer law is used, and absorption by pure molecule is depended onto molar concentration (mol amount per volume), molar extinction coefficient, and length of the cell (cuvett; usually light-path length 1 cm, more long may be good to lower the CV values). Presence of pure molecules is only achievable by the purification and/or HPLC separation; i.e., the linear calibration line inserting zero point is obtainable. Ordinary photometric assays including ELISA containing many interfering molecules are not quantitative due to non-separation (or raw) giving only the sadly bent-calibration curve (or correlation curve). Nano drop may be applicable only onto purified DNA and purified protein, but less in preciseness (giving larger range) since light path length is too short (1 mm). Spectrofluorophotometer is similar although interference by other molecules may be reduced. Therefore, atomic absorption spectrophotometer (AAS) may become more quantitative if sample is pure (HPLC-AAS is desirable).
MS; not quantitative since very narrow region is detected and flight of molecules or fragments of molecule depends on relative molecular mass (Mr), but may be usefull in identification of small molecules, which have very low UV absorption such as glycosides, fatty acids, and cholesterols, via estimating Mr with two molecues as Mr standards.
Gas-chromatograph; quantitative only on volatile molecules, although derivatization methods have been developed.
X-ray or gamma-ray inspection equipment; not quantitative since sample atoms emit the radiation ray in non-parametric manner (non-Gaussian distribution), and only the information about the median and range may be obtainable.
Hi, in my opinion "fingerprint" by chromatography means comparing the chromatograms of sample(s) and standards reference material(s); for example for checking the quality of herbal drug A, its chromatograms will be compared to authentic standard (could be by TLC, GC-FID/MS-MS, HPLC/LC UV/DAD/MS-MS), if their chromatograms are identical, we can say their chemical contents could be identical, but of course the results by LC MS-MS is more accurate compare to result using TLC, HPLC-UV/DAD. For evaluating the results it is recommended to apply MVA such as PCA or SIMCA, I attach a nice publication from Prof. Wolfender, Geneva
the contest of finger print analysis is not clear.
I am working with a waste management company, where a waste sample will be analyzed before sending the shipment to land fill (comprehensive analysis)find out whether it is hazardous or non-hazardous by suitable analyses when complete it will be characterized. Then the shipment this waste send for disposal where a sample will be taken to analysis again (finger print) the result must match with comprehensive analysis.
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