ABSTRACT
Purpose: We investigated validation and optimization of ultrasound-assisted dispersive liquidliquid microextraction (UADLLME) as a preparation method for detection of methadone in saliva samples. Methods: We used blank and methadone-containing saliva samples and also standard methadone solution. Sodium hydroxide and chloroform were added to samples and they were held in ultrasonic bath. Then preparations were centrifuged and extracted analyte was analyzed by gas chromatography-mass spectrometry (GC-MS). Accuracy was measured by Intra and between-day mean relative errors (RE). Precision was assessed by coefficient of variation (CV). Recovery, specificity, linearity and limits of detection and quantification were also determined. Optimization was conducted for ultrasound duration, pH and extraction phase volume. Efficiency of dispersive liquid-liquid microextraction (DLLME) and UADLLME were compared. Results: Intra and between-day accuracies (2.3 -7.5%), recovery (89.4-115.5%) and precision (5.2-11.3%) were all acceptable. Calibration curve was linear in the concentration range of 150 ng/mL-10 µL/mL with R2 >0.9995 and equation of y=86.901x-5342.5. Limits of detection and quantification were 50 and 150 ng/mL, respectively. Specificity was measured by comparing retention times of saliva samples (containing methadone metabolites and other commonly used drugs) during UADLLME/GC-MS analysis and no interference was observed. Recovery of UADLLME was 1.4 of DLLME. Solvent and sample volumes required for UADLLME were 1/200 and 1/20 of DLLME. The greatest efficiency obtained at pH of 10, with ultrasound treatment duration of 5 minutes and extraction phase volume of 1000 µL. Conclusion: Study found that UADLLME/GC-MS is a valid and efficient method for detection of methadone in oral fluid.
ABSTRACT
OBJECTIVES: Human hyoid is sexually dimorphic and is useful for sexing unknown skeletal remains. We aimed to find sex prediction potential of three linear dimensions of hyoid bones obtained from a series of cadavers with Persian ethnicity. METHODS: This cross-sectional study was carried out in 2015 at Forensic Pathology Organization of Tehran, Iran. We directly measured three linear dimensions of a series of hyoid samples obtained from cadavers during their neck autopsy in a convenience method. These dimensions were width, length and distance between lesser horns of hyoid. Height and weight of cadavers were also documented. Cadavers were of Persian ethnicity and at least 25-year-old. Data were analyzed by SPSS16. Logistic Regression Model was applied to find independent sex predictor(s) of hyoid. Statistically significant level was considered <0.05. RESULTS: Hyoids of 349 adult cadavers (176 females and 173 males) with mean±SD age of 39.91±8.13years were investigated. Male cadavers had significantly higher BMI values (p-value<0.001). Mean±SD for width, length and distance between lesser horns of hyoids were 34.45±4.70, 34.61±4.67 and 22.71±2.80mm, respectively. All measured dimensions had greater mean values in males (all with p-values<0.001). After adjusting for BMI, length and distance between lesser horns of hyoid were independent predictors of sex with odd's ratio of 4.67 and 1.97, respectively. Combining these two measurements provided sex classification accuracy of 97.4%. CONCLUSION: Special metric hyoid indicators can help in accurate sexing of skeletal remnants of adult Iranians. Further studies will find the strongest sex predictors of hyoid bones among Persians.
