ADL
İ TIP DERGİSİ
Journal of Forensic Medicine
Adli T
ıp Dergisi 1989; 5(3-4): 131-134
132 P. KIKIZ, P. MANGW, A. LUGNIER, AT CIIAUMONT
Due to the inercasing presence of this analyzer, based on fluorescence polarisation immunoassay (FPlA) (1), several authors have recently proposed its employ in cvaiuating drugs concentrations in other mediums than plasma and urine, such as l ido-caine, phenytoin and phenobarbital in post-mortem blood (2), morphine in hair (3), or in whole blood, liver and bile (4).
Because hemolysis does not interfere with fluorcscence polarization assays, it was previously demonstrared that the TDX could be usefull for the routine estimation of phenobarbital in post-mortem whole blood samples (5). Moreover, wc havc rcccntly demonstrated a good correlation betwecn HPLC and FPIA in analyzing quinidine in wholc blood, urine, vitrcous humor and bile (6),
In order to validate the use of the TDX İn forensic toxicology, wc determined phenobarbital and quinidine (associatcd in France, under the commercial name NatisCdineR concentrations by TDX and by HPLC in whole bIood, urine, bile, stomach
contents and liver from a fatal case.
CASE REPORT
A 33 -year old white fcmale was found dead in her home with 2 empty boxes of NatisedineR (40 tableıs of 100 mg of quinidine-phenyIethylbarbiıurate). At the autopsy, no specific anatomic cause of death was found.
MATERIALS AND METHOD
fluids sampIes were dilutcd with twice the volum e of saline. Portions of Iiver were blended with an cqual weight of saline; the homogenate was eentrifuged at 2000 x g for 5 min to sediment particulaıe matter.
The same day, ıhe autopsy specimens were analyzed in parallel by high-perfonnance Iiquid chromatography (7,8) and by the TDX analyzer.
The FPIA analyses were perfonned by the TDX system of Abbott Laboratorics with the phenobarbital scrum and quinidine serum rcagent packs, calibrators, controls, buffer supplied by the manufacturer.
RESULTS AND DISCUSSION
The results, cxpressed in Table 1, clearIy indicate agreement in the quinidine and phenobarbital concenlrations measured by both methods and thus demonstrate the abiIity to use the TDX analyzcr to assay quinidine and phenobarbital in other samples than those proposcd by the manufacrurer.
A positive bias in the TDX results relative to the HPLC results for phenobarbital was found. However, for praLİcal purposes the difference in results is negligible.
The TDX-Quinidine rcagent measures total level of quinidine and its metab olites(O-desmethylquinidine, 3- hydroxyquinidine) and congeners (dihydroquinidine, always
Application of the Abbott TDX für Detennination of Quinidine and PhcnobarbiıaL. 133
presenı in amount of 10 % of the total quinidine), and the TDX response is proportional
to [heir cOl1centration-dcpendant cross-reactivity (at LO mg/I, the % cross reacıiviry for dihydroCJuinidine, 0
-
desmethylquinidine and 3-hydroxyquinidine is 66.0, 44.0 and 23, respecıively) (9). Therefore, the TDX correlation with HPLC for quinidine cannot be established, but results indicated that the TDX could be a fast alternatiye to liquidchromatography.
Dilution with saline was necessary for two reasons: to bring values within the range of the calibration concentrations and to decrease the blank inıensity of the bile and the liver, probably because of the natural fluorescence of the bile pigments and the ehromophores in the liver matrices.
The TDX analyzer, being based on fluorescent polarization immunoassay, is much less subject to interference by color or turbidity than other immunological techniques that are based on spectroscopic measuremenL Posı-mortem bile and liver are usually not measurable by EMlT or chromatography wilhouı several extraction steps. This paper shows the merits of the Abbott TDX in screening rapidly (15 min) these samples for quinidine and phenobarbita1, using only 50 fLl of sample.
Table ı. Comparison of the eoncentrations (mgll) of quinidine and phenobarbiıal in forensic samples using ıll'LC and the TDX analyzer
Specimens Quinidine 3-Hydroxyquinidine Quinidine Phenobarbiıal
HPLC HPLC TDX HPLC Wholeblood 31.6 6.8 40.8 36.9 Uıine 554.6 425.8 674.0 14.5 Bile 59.5 39.7 140.4 23.3 Stomach 369.5 9.0 562.4 138.2 cüntents (75 ml) Liver 49.5 14.9 102.8 45.7 REFERENCES
Jollcy, Yl.E. (1981) J. Anal. Toxicol., 5,236-240.
2 CapIan, Y.IL., Levine, B. (1988) 1. Anal. Toxicol., 12, 265-267.
3 Frarıccschine, A., Morüsini, L., Dcll'Anna L. (1987) Clin. Chem., 11, 2125. 4 Lee, C, Lee, ı ı. (1989) 1. AnaL. Toxicol., 13, 50-56.
Phenobarbital TDX 39.0 22.6 39.2 164.8 47.6
Adli T
ıp Dergisi 1989; 5(3-4): 131-134
MANGIN, A. LUGNIER .
• E.K., Krasselt, W.G., Mueggler. Anal. Toxicol.. 11,257259.
6 Kiniz, 1'., Mangin, P., Lugnier, A., Chawnoni, A. (ıı,ıııı,ı) Clin. Chem., accepted for publication. 7 Kates, R.E., Mc Kennon, D.W., Comstoek, J.J. (1978) J. Pfuırm. Sci., 67,269-270.
8 Mangin, P., Lugnicr, A., Olaumont, A. (1987) J. Anal. Toxicol., 11, 27-30.
9 TDX system assays manual (1986) Toxicology/Abused Drug Assays-TDX Phenobarbital, TDX Quinidine, Manual Abbott Laboratories Ltd, Abbott Park, IL.
Reprints requı:si Dr. P. Kintz Institut de Medecinc ı ı, me Humann 67085 Strasbourg.
