The detection of hydromorphone in urine specimens with high morphine concentrations

A previous study suggested that small amounts of morphine are metabolically converted to hydromorphone. In the present study, morphine positive urine specimens obtained from a postmortem laboratory and a random urinalysis program were tested for morphine, codeine, hydromorphone, hydrocodone, oxymorphone, and oxycodone to assess the possibility that small amounts of hydromorphone are produced from the metabolism of morphine. The opioids were analyzed by gas chromatography-mass spectrometry as their respective trimethylsilyl derivatives following solid phase extraction. The limit of detection for hydromorphone was 5 ng/mL. A total of 73 morphine positive urine specimens were analyzed, with morphine concentrations ranging from 131 to 297,000 ng/mL. Hydromorphone was present at a concentration > or =5 ng/mL in 36 of these specimens at concentrations ranging from 0.02% to 12% of the morphine concentration. Hydrocodone was not detected in these specimens at the assay detection limit of 25 ng/mL. These results support earlier work suggesting that the detection of hydromorphone in urine specimens does not necessarily mean that exogenous hydromorphone or hydrocodone was used.     

超分子溶剂萃取-气相色谱-串联质谱法检测尿液中苯二氮䓬类药物

目的建立一种尿液中9种苯二氮?类药物的超分子溶剂样品气相色谱-串联质谱(gas chromatography-tandem mass spectrometry,GC-MS/MS)分析方法。方法含9种苯二氮?类药物对照品的尿液样品用四氢呋喃和1-己醇组成的超分子溶剂进行液液萃取,取溶剂层氮吹至干,残余物用甲醇复溶后进行GC-MS/MS分析,数据采集方式为多反应监测模式,采用内标法定量。结果尿液中地西泮、咪达唑仑、氟硝西泮和氯氮平质量浓度在1~100ng/mL,劳拉西泮和阿普唑仑质量浓度在5~100ng/mL,硝西泮和氯硝西泮质量浓度在2~100ng/mL,艾司唑仑在质量浓度0.2~100ng/mL范围内具有良好的线性关系,相关系数为0.9991~0.9999,定量下限为0.2~5ng/mL,提取回收率为81.12%~99.52%,日内精密度[相对标准偏差(relative standard deviation,RSD)]和准确度(偏倚)分别小于9.86%、9.51%;日间精密度(RSD)和准确度(偏倚)分别小于8.74%、9.98%。室温和-20℃条件下,尿液中9种药物在15d内具有良好的稳定性。8名志愿者单摄口服阿普唑仑片后,在8~72h内尿液中阿普唑仑的质量浓度为6.54~88.28ng/mL。结论本研究建立的尿液中9种苯二氮?类药物的超分子溶剂萃取-GC-MS/MS分析方法,简便、快速、准确、灵敏,可为临床治疗及司法鉴定中苯二氮?类药物中毒监测提供技术支持。     

Deaths Involving Methylenedioxypyrovalerone (MDPV) in Upper East Tennessee

Two deaths involving 3, 4‐methylenedioxypyrovalerone (MDPV) are reported. MDPV is a synthetic cathinone stimulant found in “bath salts” with neurological and cardiovascular toxicity. Biological specimens were analyzed for MDPV by GC/MS and LC/MS. A White man was found dead with signs of nausea and vomiting after repeatedly abusing bath salts during a weekend binge. Femoral venous blood and urine had MDPV concentrations of 39 ng/mL and 760 ng/mL. The second fatality was a White man with a history of drug and bath salt abuse found dead at a scene in total disarray after exhibiting fits of anger and psychotic behavior. Femoral venous blood and urine had MDPV concentrations of 130 ng/mL and 3800 ng/mL. The blood and urine MDPV concentrations are within the reported recreational concentration ranges (blood 24–241 ng/mL and urine 34–3900 ng/mL). Both decedents’ deaths were attributed to relevant natural causes in a setting of MDPV abuse.     

Elimination of 7-aminoflunitrazepam and flunitrazepam in urine after a single dose of Rohypnol

The hypnotic benzodiazepine flunitrazepam (Rohypnol) has been identified as the drug of choice for the purposes of "drugging" unsuspecting victims and raping them while they are under the influence of this substance. The objective of this paper was to study elimination of flunitrazepam and 7-aminoflunitrazepam in urine collected from ten healthy volunteers who received a single 2 mg oral dose of Rohypnol, to determine how long after drug administration 7-aminoflunitrazepam can be detected. A highly sensitive NCI-GC-MS method for the simultaneous quantitation of flunitrazepam (LOQ 100 pg/mL) and 7-aminoflunitrazepam (LOQ 10 pg/mL) in urine was developed. All samples were screened for benzodiazepines using optimized micro-plate enzyme immunoassay. The highest concentrations of 7-aminoflunitrazepam (70-518 ng/mL) and flunitrazepam (0.7-2.8 ng/mL) in urine were observed 6 h after drug administration in nine subjects and after 24 h in one subject. In six subjects 7-aminoflunitrazepam was detected up to 14 days after flunitrazepam administration, in one subject up to 21 days and in three subjects up to 28 days. In urine samples collected from six volunteers, flunitrazepam was detected three days after Rohypnol intake, in three subjects 24 h, and in one subject 5 days later. Benzodiazepine micro-plate enzyme immunoassay kit allowed the detection of flunitrazepam and metabolities 5 to 21 days after drug administration.     

人体不同体液内PSA含量及其法医学意义

目的检测人体不同体液内前列腺特异抗原(PSA)含量,探讨其法医学价值。方法收集成年人(19～63岁)晨尿40份(男28份、女12份)、血液58份(男45份、女13份)、唾液25份(男14份、女11份);青少年(10～15岁)男性晨尿205份;哺乳期(25～31岁)女性乳汁9份;使用Cobas e411型全自动电化学发光免疫分析系统及T-PSA定量测定试剂盒,检测各样本T-PSA含量;分析不同体液及不同年龄青少年男性尿液PSA含量差异。结果除男、女性唾液外,其它样本均可检测到PSA,其中成年男性尿液含量最高,与其它体液比较具有显著性差异(P<0.000 1);青少年男性各年龄组尿液PSA含量随年龄逐年增高,11岁及以下年龄组含量不足1ng/mL,14岁及以上年龄组可超过1 000ng/mL。结论前列腺发育成熟的男性尿液PSA含量较高,在进行精液斑的法医学检验时应给予充分注意。     

Urinary excretion profiles of 11-nor-9-carboxy-delta9-tetrahydrocannabinol and 11-hydroxy-delta9-THC: cannabinoid metabolites to creatinine ratio study IV

The objective of this study was to compare urinary excretion patterns of two cannabinoid metabolites in subjects with a history of chronic marijuana use. The first metabolite analyzed was nor-9-carboxy-delta9-tetrahydrocannabinol (delta9-THC-COOH), the major urinary cannabinoid metabolite that is pharmacologically inactive. The second metabolite 11-OH-delta9-THC is an active cannabinoid metabolite and is not routinely measured. Urine specimens were collected from four subjects on 12-20 occasions > or = 96 h apart in an uncontrolled clinical setting. Creatinine was analyzed in each urine specimen by the colorimetric modified Jaffé reaction on a SYVA 30R biochemical analyzer. All urine specimens analyzed for 11-OH-delta9-THC had screened positive for cannabinoids with the EMIT II Plus cannabinoids assay (cut-off 50 ng/mL) on a SYVA 30R analyzer and submitted for delta9-THC-COOH confirmation by GC-MS (cut-off concentration 15 ng/mL). Eleven-OH-delta9-THC was measured by GC-MS with a cut-off concentration of 3 ng/mL. Both GC-MS methods for cannabinoid metabolites used deuterated internal standards for quantitative analysis. The mean (range) of urinary delta9-THC-COOH concentration was 1153 ng/mL (78.7-2634) with a cut-off of 15 ng/mL. The mean (range) of delta9-THC-COOH/creatinine ratios (ng/mL delta9-THC-COOH/mmol/L creatinine) was 84.1 (8.1-122.1). The mean (range) urinary of 11-OH-delta9-THC concentration was 387.6 ng/mL (11.9-783) with a cut-off of 3 ng/mL, and the mean (range) of 11-OH-delta9-THC/creatinine ratio (ng/mL 11-OH-delta9-THC/mmol/L creatinine) was 29.7 (1.2-40.7). Of the 63 urine specimens submitted for delta9-THC-COOH confirmation by GC-MS, 59/63 urine specimens (94%) were positive for delta9 -THC-COOH and 51/63 (81%) were positive for 11-OH-delta9-THC. Overall, the concentrations of 11-OH-delta9-THC in urine specimens collected > or = 96 h apart were lower than delta9-THC-COOH concentrations in 50/51 of the urine specimens in this population. Further urinary cannabinoid excretion studies are needed to assess whether 11-OH-delta9-THC analyses have a role when assessing previous marijuana or hashish use in chronic users whose urine specimens remain positive for delta9-THC-COOH for an extended period of time after last drug use.     

Atropine Eye Drops: An Unusual Homicidal Poisoning

In March 2009, the body of a 51‐year‐old man was found in the boot of his car. The body had been frozen before being dismembered at the abdomen. The autopsy failed to determine the cause of death. Systematic toxicological analyses of the victim's peripheral blood and urine showed the presence of atropine, a powerful anticholinergic. Atropine was therefore specifically detected and quantified throughout the victim's biologic samples by HPLC‐MS² in the biologic fluids and UHPLC‐MS² in the hair. The atropine concentrations were 887 ng/mL in the cardiac blood, 489 ng/mL in the peripheral blood, 6693 ng/mL in the gastric contents (1.1 μg), 6753 ng/mL in the urine, and 2290 pg/mg in the hair. The blood concentrations measured in the decedent were consistent with an overdose of atropine, which was determined as the cause of death. The manner of death was a homicide with criminal intent.     

Detection and quantification of low levels of benzoylecgonine in equine urine

Cocaine (COC) is a highly addictive plant alkaloid expressing strong psychostimulatory effect. It has no medical use in equine veterinary practice. The contamination of the environment with cocaine such as its presence on the US paper currency has been reported few times. There are anecdotal reports of low benzoylecgonine (BE) concentrations (usually much less than 100 ng/mL) being found in urine of race horses. In order to protect horsemen against harsh penalties associated with the presence of trace amounts of BE in horse urine as a result of environmental contamination, in February 2005 the Illinois Racing Board issued new medication rules that established the threshold level of 150 ng/mL for BE in equine urine. The penalties associated with this rule provide for increasing fines ($250, $500, $1000) with successive positive reports against a trainer for levels of BE below 150 ng/mL. A total of 19,315 urine samples were collected over the 2-year period of time from winning horses (both harness and thoroughbred) at race tracks in Illinois for routine drug screening (ELISA). The presence of BE was confirmed by GC/MS in 28 urine samples (0.14%). The concentration range for BE in harness horses (21 detections) was < 5-91 ng/mL, and for thoroughbred (seven detections) was 7-52 ng/mL. To date, the laboratory has not reported concentrations of BE that exceed the established threshold concentration of 150 ng/mL.     

Gas chromatographic/mass spectrometric analysis of morphine and codeine in human urine of poppy seed eaters

In this study, poppy seeds were examined for a natural constituent that might serve as a maker for the seeds' ingestion as opposed to opiate abuse. Thebaine was selected as possible marker, since it was found to be a component of all poppy seeds examined and was not a natural component of different heroin samples. During the course of this investigation, a new extraction and cleanup procedure was developed for the gas chromatographic/nitrogen phosphorus detection (GC/NPD) and gas chromatographic/mass spectrometric (GC/MS) analysis of morphine and codeine in urine. A linear response, over a concentration range of 25 to 600 ng/mL, was obtained for codeine and morphine (r = 0.9982 and 0.9947, respectively). The minimum detectable level (LOD) and limit of quantitation (LOQ) for morphine were 10 and 30 ng/mL, respectively; whereas LOD and LOQ for codeine were 2 and 8 ng/mL, respectively. The coefficients of variance (CV, n = 6) for morphine and codeine analyses at the 100-ng/mL level were 13.3 and 4.6%, respectively. This procedure was used for the analysis of urine samples from five poppy seed eaters who each ingested 200 g of poppy seed cake. Results indicated that significant amounts of morphine and codeine are excreted in urine and that in all subjects, at least at one point in time, the apparent morphine concentration as determined by radioimmunoassay (RIA) analysis exceeded the cutoff value (300 ng/mL) established for screening. Thebaine was not detected in urine specimens collected following poppy seeds ingestion and thus could not be used as a marker.     

Ethyl glucuronide concentrations in two successive urinary voids from drinking drivers: relationship to creatinine content and blood and urine ethanol concentrations

The concentrations of alcohol in blood (BAC) and two successive urine voids (UAC) from 100 drunk drivers were compared with the concentration of ethyl glucuronide (EtG), a minor metabolite of ethanol in urine, and the urinary creatinine content as an indicator of dilution. The subjects consisted of 87 men with mean age 42.2+/-14.2 years (+/-standard deviation, S.D.) and 13 women with mean age 42.5+/-14.4 years. Ethanol was measured in blood and urine by headspace gas chromatography (GC) and EtG was determined in urine by liquid chromatography-mass spectrometry (LC-MS). The mean UAC was 2.53+/-1.15g/l for first void compared with 2.35+/-1.17g/l for second void, decreasing by 0.18+/-0.24g/l on average (P<0.001 in paired t-test). The ratios of UAC/BAC were 1.35+/-0.25 for first void and 1.20+/-0.16 for second void and the difference of 0.15+/-0.27 was statistically significant (P<0.001). The UAC/BAC ratio was not correlated with creatinine content of the urine specimens, whereas the concentration of urinary EtG was positively correlated with creatinine (r=0.64 for first void and r=0.62 for second void). The UAC was not correlated with urinary EtG directly (r=-0.03 for first void and r=0.08 for second void) but after adjusting for the relative dilution of the specimens (EtG/creatinine ratio) statistically significant positive correlations were obtained (r=0.58 for first void and r=0.57 for second void). The dilution of the urine, as reflected in creatinine content, is important to consider when EtG measurements are interpreted. The excretion of EtG in urine, like glucuronide conjugates of other drugs, is influenced by diuresis. EtG represents a sensitive and specific marker of acute alcohol ingestion with applications in clinical and forensic medicine.     

Concentrations of unconjugated morphine, codeine and 6-acetylmorphine in urine specimens from suspected drugged drivers

Concentrations of unconjugated morphine, codeine and 6-acetylmorphine (6-AM), the specific metabolite of heroin, were determined in urine specimens from 339 individuals apprehended for driving under the influence of drugs (DUID) in Sweden. After an initial screening analysis by immunoassay for 5-classes of abused drugs (opiates, cannabinoids, amphetamine analogs, cocaine metabolite and benzodiazepines), all positive specimens were verified by more specific methods. Opiates and other illicit drugs were analyzed by isotope-dilution gas chromatography-mass spectrometry (GC-MS). The limits of quantitation for morphine, codeine and 6-AM in urine were 20 ng/mL. Calibration plots included an upper concentration limit of 1000 ng/mL for each opiate. We identified the heroin metabolite 6-AM in 212 urine specimens (62%) at concentrations ranging from 20 ng/mL to > 1000 ng/mL. The concentration of 6-AM exceeded 1000 ng/mL in 79 cases (37%) and 31 cases (15%) were between 20 and 99 ng/mL. When 6-AM was present in urine the concentration of morphine was above 1000 ng/mL in 196 cases (92%). The concentrations of codeine in these same urine specimens were more evenly distributed with 35% being above 1000 ng/mL and 21% below 100 ng/mL. These results give a clear picture of the concentrations of unconjugated morphine, codeine and 6-acetylmorphine that can be expected in opiate-positive urine specimens from individuals apprehended for DUID after taking heroin.     

Fatal Intoxication with α‐PVP,a Synthetic Cathinone Derivative

This study presents the fatal case of a young man who was admitted to the ICAU due to sudden cardiac arrest. An interview revealed that the patient had taken some unspecified crystals. From the moment of admission, his condition deteriorated dramatically as a result of increasing circulatory insufficiency. After a few hours, sudden cardiac arrest occurred again and the patient was pronounced dead. In the course of a medicolegal autopsy, samples of biological material were preserved for toxicology tests and histopathological examination. The analysis of samples using the LC‐MS/MS technique revealed the presence of α‐PVP in the following concentrations: blood—174 ng/mL, urine—401 ng/mL, brain—292 ng/g, liver—190 ng/g, kidney—122 ng/g, gastric contents—606 ng/g. The study also presents findings from the parallel histopathological examination. Based on these findings, cardiac arrest secondary to intoxication with alpha‐PVP was determined as the direct cause of the patient's death.     

The detection of psilocin in human urine

Pharmacokinetic studies of psilocybin in humans have shown the rapid dephosphorylation of psilocybin to psilocin with further conversion to 4-hydroxy-tryptophole (4HT) and 4-hydroxyindole-3-acetic acid (4HIAA) in plasma. Our study shows that psilocin also undergoes conjugation and can be found in the urine as the psilocin-glucuronide conjugate. Recoveries after enzymatic hydrolysis of the urine with beta-glucuronidase (Helix Pomatia or E. Coli) when compared to non-hydrolyzed urine confirmed the presence of the glucuronide. Detection of psilocin from hydrolyzed and extracted samples was optimized for GC/MS by derivatization with MSTFA. The method developed allows for the detection of psilocin in urine with a limit of quantitation of 10 ng/mL, based on 5 mL of spiked urine. Using this method, our laboratory has confirmed the presence of psilocin in 6 out of 8 urine samples, with concentrations ranging from 10 ng/mL to greater than 200 ng/mL. Before implementation of the hydrolysis and derivatization steps, our limit of detection was 200 ng/mL, based on spiked urine standards. No case samples were positive without hydrolysis and derivatization.     

Evaluation of the One-Step ELISA kit for the detection of buprenorphine in urine, blood, and hair specimens

A solid-phase enzyme immunoassay involving microtiter plates was recently proposed by International Diagnostic Systems corporation (IDS) to screen for buprenorphine in human serum. The performance of the kit led us to investigate its applicability in other biological matrices such as urine or blood, and also hair specimens. Low concentrations of buprenorphine were detected with the ELISA test and confirmed by HPLC/MS (buprenorphine concentrations measured by HPLC/MS: 0.3 ng/mL in urine, 0.2 ng/mL in blood, and 40 pg/mg in hair). The intra-assay precision values were 8.7% at 1 ng/mL of urine (n = 8), 11.5% at 2 ng/mL in serum (n = 8), and 11.5% at 250 pg/mg of hair (n = 8), respectively. The immunoassay had no cross-reactivity with dihydrocodeine, ethylmorphine, 6-monoacetylmorphine, pholcodine, propoxyphene, dextromoramide, dextrometorphan at 1 and 10 mg/L, or codeine, morphine, methadone, and its metabolite EDDP. A 1% cross-reactivity was measured for a norbuprenorphine concentration of 50 ng/mL. Finally, the immunoassay was validated by comparing authentic specimens results with those of a validated HPLC/MS method. From the 136 urine samples tested, 93 were positive (68.4%) after the ELISA screening test (cutoff: 0.5 ng/mL) and confirmed by HPLC/MS (buprenorphine concentrations: 0.3-2036 ng/mL). From the 108 blood or serum samples screened, 27 were positive (25%) after the ELISA test with a cutoff value of 0.5 ng/mL (buprenorphine concentrations: 0.2-13.3 ng/mL). Eighteen hair specimens were positive (72%) after the screening (cutoff: 10 pg/mg) and confirmed by LC/MS (buprenorphine concentrations: 40-360 pg/mg). The ELISA method produced false positive results in less than 21% of the cases, but no false negative results were observed with the immunological test. Four potential adulterants (hypochloride 50 mL/L, sodium nitrite 50 g/L, liquid soap 50 mL/L, and sodium chloride 50 g/L) that were added to 10 positive urine specimens (buprenorphine concentrations in the range 5.3-15.6 ng/mL), did not cause a false negative response by the immunoassay.     

Acetyl Fentanyl: Trends and Concentrations in Metro Detroit

Acetyl fentanyl (N‐[1‐phenethylpiperidin‐4‐yl]‐N‐phenylacetamide) is a potent opioid analgesic with no medicinal uses. We report deaths between 2016 and 2017 at the Medical Examiner's Office in Detroit, MI where acetyl fentanyl was found in the decedent's blood and compare them to previously published deaths between 2015 and 2016. The recent cases (cohort B) had a mean acetyl fentanyl concentration of 0.9 ng/mL (range: 0.1–5.3 ng/mL) and an associated higher concentration of fentanyl along with multiple other drugs present. The older cases (cohort A) had higher concentrations of acetyl fentanyl (mean: 8.9 ng/mL; range: 0.28–37 ng/mL) with lower, yet still toxic, concentrations of fentanyl. We conclude that the cause of death in these recent cases was likely multiple drug toxicity with fentanyl and that the consistently observed lower peripheral blood concentrations of acetyl fentanyl are most likely an artifact in the manufacture of the consumed illicit fentanyl.     

Simultaneous determination of total human and male DNA using a duplex real-time PCR assay

A single duplex assay to determine both the amount of total human DNA and the amount of male DNA in a forensic sample has been developed. This assay is based on TaqMan technology and uses the multicopy Alu sequence to quantitate total human DNA and the multicopy DYZ5 sequence to quantitate Y chromosomal (male) DNA. The assay accepts a wide concentration range of input DNA (2 muL of 64 ng/microL to 0.5 pg/microL), and also allows detection of PCR failure. The PCR product sizes Alu (127 bp) and DYZ5 (137bp) approximate that of the smaller short tandem repeats (STRs) which should make the assay predictive of STR success with degraded DNA. The assay was optimized for probe/primer concentrations and BSA addition and validated on its reproducibility, on its human specificity, on its nonethnic variability, for artificial mixtures and adjudicated casework, for the effect of inhibitors and for state of DNA degradation. This assay should prove very usual in forensic analyses because knowing the relative amounts of male versus female DNA can allow the examiner to decide which samples may yield the most probative value in a case or direct the samples to methods that would yield the greatest information.     

Oral fluid testing for cannabis: on-site OraLine IV s.a.t. device versus GC/MS

Saliva or "oral fluid" has been presented as an alternative matrix to document drug use. The non-invasive collection of a saliva sample, which is relatively easy to perform and can be achieved under close supervision, is one of the most important benefits in a driving under the influence situation. Moreover, the presence of Delta9-tetrahydrocannabinol (THC) in oral fluid is a better indication of recent use than when 11-nor-Delta9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) is detected in urine, so there is a higher probability that the subject is experiencing pharmacological effects at the time of sampling. In the first part of the study, 27 drug addicts were tested for the presence of THC using the OraLine IV s.a.t. device to establish the potential of this new on-site DOA detection technique. In parallel, oral fluid was collected with the Intercept DOA Oral Specimen Collection device and tested for THC by gas chromatography mass spectrometry (GC/MS) after methylation for THC (limit of quantification: 1 ng/mL). The OraLine device correctly identified nine saliva specimens positive for cannabis with THC concentrations ranging from 3 to 265 ng/mL, but remained negative in four other samples where low THC concentrations were detected by GC/MS (1-13 ng/mL). One false positive was noted. Secondly, two male subjects were screened in saliva using the OraLine and Intercept devices after consumption of a single cannabis cigarette containing 25mg of THC. Saliva was first tested with the OraLine device and then collected with the Intercept device for GC/MS confirmation. In one subject, the OraLine on-site test was positive for THC for 2 h following drug intake with THC concentrations decreasing from 196 to 16 ng/mL, while the test remained positive for 1.5 h for the second subject (THC concentrations ranging from 199 to 11 ng/mL). These preliminary results obtained with the OraLine IV s.a.t. device indicate more encouraging data for the detection of THC using on-site tests than previous evaluations.     

4种固相颗粒吸附法提取滤纸血痕DNA效果的比较

目的探讨4种固相颗粒吸附法提取滤纸血痕样本DNA的效果。方法含有1μL静脉血的滤纸血痕180份,分为4组,每组45份。分别采用4种固相颗粒吸附法(DNAIQ~(TM)系统、D盾超敏DNA提取试剂盒、超高效硅珠纯化DNA提取试剂盒和常规的硅珠法)对上述样本进行DNA提取,对比各组DNA溶液的浓度及STR分型检验结果。结果 D盾超敏DNA提取试剂盒[(3.764±1.790)μg/mL]、超高效硅珠纯化DNA提取试剂盒(3.634±1.112)及常规硅珠法(3.350±1.250)提取到DNA溶液的浓度无统计学差异(P0.05),但均高于DNA IQ~(TM)系统(1.864±1.207)(P0.001);D盾超敏DNA提取试剂盒、超高效硅珠纯化DNA提取试剂盒及常规硅珠法样本图谱峰高大于DNA IQ~(TM)系统(P0.001),超高效硅珠纯化DNA提取试剂盒和常规硅珠法样本图谱峰高大于D盾超敏DNA提取试剂盒(P0.01)。结论 D盾超敏DNA提取试剂盒、超高效硅珠纯化DNA提取试剂盒及常规硅珠法对于滤纸血痕的DNA提取效率高于DNA IQ~(TM)系统;超高效硅珠纯化DNA提取试剂盒和常规硅珠提取到的DNA溶液可能具有更高的质量。     

STR Profiles from DNA Samples with "Undetected" or Low Quantifiler™ Results

Abstract:  Screening methods capable of identifying DNA samples that will not yield short tandem repeat (STR) profiles are desired. In the past, quantitation methods have not been sensitive enough for this purpose. In this study, low level DNA samples were used to assess whether Quantifiler™ has a minimum quantitation value below which STR profiles would consistently fail to be detected. Buccal swabs were obtained and the DNA extracted, quantified, and serially diluted to concentrations ranging from 0.002 to 0.250 ng/μL. Samples were analyzed once with Quantifiler™, followed by Profiler Plus™ amplification and capillary electrophoresis analysis. An absolute minimum value below which STR results were unobtainable could not be defined. From the 96 low level samples tested, STR loci (including one full profile) were successfully amplified and detected from 27% of the samples "undetected" by Quantifiler™. However, no STR alleles were detected in 73% of these "undetected" samples, indicating that Quantifiler™ data may be useful for predicting STR typing success.