Objective To establish the m ethod to analyze γ-hydroxybutyric acid (GHB ) and its precursors 1,4-butanediol (1,4-B D ) and gam m a-butyrolactone (GBL) in urine through LC-M S/M S and provide evi-dence for related cases. Methods GHB-d6 and M O R-d3 were used as the internal standard. The urine sam ple w as separated by LC after protein precipitation w ith m ethanol. The electrospray ion source w as for ionization. E ach com pound w as detected through m ultiple-reaction m onitoring (M R M ) m ode. Results The lim its of detection of GHB and its precursors 1,4-B D and GBLwere 0.1, 0.1 and 2μg/m L. The accuracy w as 87.6% -98.1% . The intra-day and inter-day precisions were less than 15% and m atrix ef-fects were higher than 80% . Conclusion The m ethod is high sensitive, sim ple, rapid, specific and w ith high reliability. This study has provided technical support and basic data for forensic cases involving GHB .

Objective To evaluate the clinical performance of INNOVANCE D-Dimer,and provide information for clinical application.Methods 402 cases of sodium citrate anticoagulant blood were tested with INNOVANCE assay and PLUS assay on CA7000 analyzer to measure plasma D-Dimer levels.VIDAS-30 immunology analyzer was also used to validate the two assays.4 patients with elevated D-Dimer were monitored continuously during 5 days using INNOVANCE assay and PLUS assay respectively,then the consistency of trend between 2 assays was analyzed.Plasma specimens added with hemoglobin,bilimbin and triglyceride were used to verify the anti-interference capability of INNOVANCE D-Dimer assay.Results In 402 specimens,the result ranges of INNOVANCE D-Dimer and PLUS D-Dimer were [2.15 (0.33,8.63)]mg/L FEU and [325.50 (123.75,974.00)] μ,g/L DDU,respectively.The consistency between two assays was poor (Z =-17.375,P =0.000),especially the results in the range of PLUS D-Dimer (201-300) μg/L DDU and (301-400) μg/L DDU,the coincidence rates were only 25％ and 15％,respectively; the coincidence rate was up to 85％ during PLUS D-Dimer (500-600) μg/L DDU; the coincidence rate was close to 100％ when PLUS D-Dimer over 700 μg/L DDU.Totally 47 of 402 cases were unmatched between two assays.Verified by VIDAS 30,83.0％ (39/47) was false negative for PLUS assay,4.3％ (2/47) was false negative for INNOVANCE assay,12.7％ (6/47) was false positive for PLUS assay.There were 5 false positives and 39 false negative for PLUS assay,totally 45 cases; Two false negative for INNOVANCE assay.Four patients with elevated D-Dimer were monitored and the results showed similar trend between 2 assays.For INNOVANCE assay,the capacity of anti-interference to free bilirubin,unconjugated bilirubin,hemoglobin,and triglyceride was up to 217 μmol/L,337 μmol/L,41.04 g/L,18.35 mmol/L,respectively.Conclusions INNOVANCE assay can markedly reduce false negative results of D-Dimer compared with PLUS assay.INNOVANCE D-Dimer has good performance on anti-interference to jaundice,hemolysis and lipemia samples.