Determination Of Oxycodone Research Articles

Bioinspired composite packed in blunt needles, integrated microextraction and determination of oxycodone and naloxone in saliva by substrate spray mass spectrometry

BackgroundOpioids are effective painkillers used for medical purposes. Their prolonged ingestion can provoke some side effects (including overdose or constipation) that are minimized by using opioid antagonists (e.g., naloxone). The rapid determination of opioids and their antagonists in biosamples is essential for an effective medical treatment. The direct combination of sample preparation and mass spectrometry (MS) fits well in this scenario. It can speed up the analysis achieving a good selectivity, which relies on the sample preparation and MS, and sensitivity levels. ResultsThis article presents a novel substrate-spray mass spectrometry interface based on a polydopamine-cotton (PDA-Cel) composite hosted inside the inner diameter of a 14-gauge blunt needle to determine oxycodone and naloxone in saliva samples. The needle is used as a microextraction device and a substrate for mass spectrometric analysis. The lack of sharpness of the 14-gauge (14G) blunt needles challenges the formation of the electrospray (ESI), and a commercial 10 μL pipette tip is proposed as a simple solution to this shortcoming. Under the optimum parameters, the proposed method was validated, obtaining limits of detection lower than 0.6 μg L−1, linear range up to 200 μg L−1, and linearity better than 0.9915. Relative standard deviation (RSD) and relative recoveries (RR) were studied at three different concentration levels (2, 40, and 200 μg L−1). RSD values were better than 20.7 %, and RR ranged from 90 to 114 %. Finally, a positive sample from a patient under medical treatment was analyzed. Significance and novelty14G blunt needles have been demonstrated as effective extraction devices due to their low price (<0.15 € per extraction unit), their better safety (avoiding finger pricking), and their higher hosting capacity (up to 8 mg of sorbent). The conductivity of stainless steel permits their use as electrospray emitters, making their direct combination to MS easier. The large variety of fibrous sorbents makes this approach versatile enough to be adapted to other analytical problems.

Determination of oxycodone and its major metabolites in haematic and urinary matrices: Comparison of traditional and miniaturised sampling approaches

Oxycodone is a widely prescribed, full agonist opioid analgesic. As such, it is used clinically to treat different kinds of painful conditions, with a relatively high potential for doping practices in athletes.In this paper, different classic and innovative miniaturised matrices from blood and urine have been studied and compared, to evaluate their relative merits and drawbacks within therapeutic drug monitoring (TDM) and to implement new protocols for anti-doping analysis. Plasma, dried blood spots (DBS) and dried plasma spots (DPS) have been studied for TDM purposes, while urine, dried urine spots (DUS) and volumetric absorptive microsamples (VAMS) from urine for anti-doping.These sampling techniques were coupled to an original bioanalytical method based on liquid chromatography-tandem mass spectrometry (LC–MS/MS) for the evaluation and monitoring of the levels of oxycodone and its major metabolites (noroxycodone and oxymorphone) in patients under pain management and in athletes. The method was validated according to international guidelines, with good results in terms of precision, extraction yield and accuracy for all considered micromatrices. Thus, the proposed sampling, pre-treatment and analysis are attractive strategies for oxycodone determination in human blood and urine, with advanced options for application to derived micromatrices. Microsampling procedures have significant advantages over classic biological matrices like simplified sampling, storage and processing, but also in terms of precision (<9.0% for DBS, <7.7% for DPS, <7.1% for DUS, <5.3% for VAMS) and accuracy (>73% for DBS, >78% for DPS, >74% for DUS, >78% for VAMS). As regards extraction yield, traditional and miniaturised sampling approaches are comparable (>67% for DBS, >74% for DPS, >75% for DUS, >75% for VAMS). All dried matrices have very low volumes, leading to a significant advantage in terms of analysis feasibility. On the other hand, this also leads to a corresponding decrease in the overall sensitivity.

Determination of oxycodone and its major metabolites noroxycodone and oxymorphone by ultra-high-performance liquid chromatography tandem mass spectrometry in plasma and urine: application to real cases.

Oxycodone is a narcotic drug widely used to alleviate moderate and severe acute and chronic pain. Variability in analgesic efficacy could be explained by inter-subject variations in plasma concentrations of parent drug and its active metabolite, oxymorphone. To evaluate patient compliance and to set up therapeutic drug monitoring (TDM), an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) assay was developed and validated for the parent drug and its major metabolites noroxycodone and oxymorphone. Extraction of analytes from plasma and urine samples was obtained by simple liquid-liquid extraction. The chromatographic separation was achieved with a reversed phase column using a linear gradient elution with two solvents: acetic acid 1% in water and methanol. The separated analytes were detected with a triple quadrupole mass spectrometer operated in multiple reaction monitoring (MRM) mode via positive electrospray ionization (ESI). Separation of analytes was obtained in less than 5 min. Linear calibration curves for all the analytes under investigation in urine and plasma samples showed determination coefficients (r2) equal or higher than 0.990. Mean absolute analytical recoveries were always above 86%. Intra- and inter-assay precision (measured as coefficient of variation, CV%) and accuracy (measured as % error) values were always better than 13%. Limit of detection at 0.06 and 0.15 ng/mL and limit of quantification at 0.2 and 0.5 ng/mL for plasma and urine samples, respectively, were adequate for the purpose of the present study. Rapid extraction, identification and quantification of oxycodone and its metabolites both in urine and plasma by UHPLC-MS/MS assay was tested for its feasibility in clinical samples and provided excellent results for rapid and effective drug testing in patients under oxycodone treatment.

Determination of Oxycodone, Noroxycodone and Oxymorphone by High-Performance Liquid Chromatography–Electrospray Ionization-Tandem Mass Spectrometry in Human Matrices: In vivo and In vitro Applications

The opioid analgesic oxycodone is widely abused and increasingly associated with overdose deaths. A sensitive analytical method was developed for oxycodone and its metabolites, noroxycodone and oxymorphone, in human plasma, urine (±enzymatic hydrolysis at 50°C for 16 h) and liver microsomes (HLMs). Liquid-liquid extraction was followed by high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry. The calibration range was 0.2-250 ng/mL for plasma and HLM and 10-5000 ng/mL for urine. Intra- and interrun accuracies were within 13.3% of target; precisions were within 12.8% for all matrices. Recoveries from plasma were: oxycodone, 75.6%; noroxycodone, 37.4% and oxymorphone, 18.2%. Analytes exhibited room temperature stability in plasma and urine up to 24 h, and freeze-thaw stability in plasma up to three cycles. In 24-h hydrolyzed urine from subjects administered intranasal oxycodone (30 mg/70 kg, n = 5), mean concentrations (ng/mL) and % daily doses excreted were: oxycodone, 1150, 6.53%; noroxycodone, 1330, 7.81% and oxymorphone, 3000, 17.1%. Oxycodone incubated with HLM produced more noroxycodone than oxymorphone. With a panel of recombinant human cytochrome P450s (CYPs), CYP2C18 and CYP3A4 produced the most noroxycodone, whereas CYP2D6 produced the most oxymorphone. These results demonstrate a new method suitable for both in vivo and in vitro metabolism and pharmacokinetic studies of oxycodone.

Determination of Oxycodone, Noroxycodone, Oxymorphone, and Noroxymorphone in Human Plasma by Liquid Chromatography-Electrospray-Tandem Mass Spectrometry

A sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of oxycodone, noroxycodone, oxymorphone, and noroxymorphone. Following solid-phase extraction, the analytes were separated on a reverse-phase column by gradient elution and analyzed by MS/MS. The analytes were found to be stable in plasma for at least three freeze-thaw cycles and 5 hours at room temperature, and also in the reconstitution solution at 8 degrees C for at least 48 hours. The lower limits of quantification were 0.1 ng/mL for oxycodone and oxymorphone and 0.25 ng/mL for noroxycodone and noroxymorphone. All calibration curves were linear up to 100 ng/mL. The extraction recoveries were more than 85%, the intraday and interday coefficients of variation were <15%, and the accuracy was >90% for all analytes at relevant plasma concentrations. The method has been used in the therapeutic drug monitoring of more than 1000 clinical plasma samples. About 50 concomitantly used drugs were tested for possible ion suppression and found not to interfere with the method. In conclusion, this method is suitable for pharmacokinetic studies in patients and healthy volunteers, and it can be applied to therapeutic monitoring of oxycodone.

Determination of Oxycodone and Hydrocotarnine in Cancer Patient Serum by High-Performance Liquid Chromatography with Electrochemical Detection

We developed an HPLC procedure using electrochemical detection for the quantitation of oxycodone and hydrocotarnine in cancer patients serum. An eluent of methanol:acetonitrile:5 mM pH 8 phosphate buffer (2:1:7) was used for the mobile phase. The calibration curve was linear in the range from 10 ng/mL to 100 ng/mL. The recovery of oxycodone and hydrocotarnine was 97.2% and 90.5%, respectively. The relative standard deviations within-runs and between-runs for the assay of oxycodone or hydrocotarnine were less than 4.8%. The method developed here was better than the method reported previously.

Simultaneous Determination of Oxycodone and Noroxycodone in Dog Plasma and Urine by HPLC, with Post‐column Chemiluminescence Detection Using Electrogenerated tris(2,2′‐Bipyridyl) Ruthenium(III)

A sensitive and specific method was developed for the determination of oxycodone (OXC) and its metabolite, noroxycodone (NOC), in dog plasma and urine by high performance liquid chromatography (HPLC) with chemiluminescence (CL) detection. Plasma samples were treated with a disposable C18‐bonded column to extract oxycodone and noroxycodone. Urine samples were treated by dilution with water. The analytes were separated on the reversed phase HPLC column and detected by CL with electrochemically oxidized tris(2,2′‐bipyridyl) ruthenium(III). The assay concentration ranges for OXC and NOC were 0.5–250 ng/mL and 2.5–1250 ng/mL in dog plasma, and 0.1–40 µg/mL and 0.5–200 µg/mL in dog urine, respectively. Recoveries of the compounds from plasma and urine were more than 87%. In the within‐run and between‐run assay, the precision values were not more than 13.3%, and the accuracy values were between −3.6% and +15.0%, respectively. The methods were applied to the pharmacokinetic study of oxycodone in dogs.

Determination of Oxycodone and Its Metabolite, Noroxycodone, in Human Plasma by HPLC with Post‐column Chemiluminescence Detection Using Electrogenerated Tris(2,2′‐Bipyridyl)ruthenium(III)

A sensitive high performance liquid chromatography (HPLC) method with post‐column chemiluminescence detection was developed for the simultaneous determination of oxycodone (OXC) and its metabolite, noroxycodone (NOC), in human plasma. Sample preparation for human plasma was performed by means of solid extraction with Sep‐Pak Vac C18 (100 mg/mL). Separation was performed by reversed‐phase HPLC using a 5‐µm Develosil ODS‐HG‐5 column (150 mm × 4.6 mm) and a mobile phase consisting of a mixture of 0.1 mol/L phosphate buffer (pH 2.6) containing 5 mmol/L sodium dodecylsulfate and methanol (53:47, v/v). Quantitation was performed by the measurement of chemiluminescence using electrogenerated tris(2,2′‐bipyridyl)ruthenium(III). The lower and upper limits of quantitation for OXC and NOC were 0.5–250 ng/mL and 1–500 ng/mL, respectively. The calibration curve for this assay showed good linearity for the concentration range of 0.5–50 ng/mL for OXC and 1–100 ng/mL for NOC. Recoveries of the studied compounds were excellent at the individual assay ranges (102.9–108.7%), and validation of the assay gave results that were satisfactory in terms of within‐run or between‐run precision (1.9–11.9% as RSD) and accuracy (−13.5% to +9.2% as bias). Stability studies showed that OXC and NOC were stable in assay solutions for at least 6 days at 4°C storage in the autosampler. OXC and NOC were also stable in human plasma for at least 48 hr at room temperature, for at least 8 months at −20°C and after five repeated freeze–thaw cycles. Furthermore, OXC and NOC were stable in human whole blood for up to 5 days at 4°C and for up to 5 hr at room temperature. This system was applied to the clinical study of cancer patients after single oral administration doses of controlled‐released tablets of OXC hydrochloride. Consequently, this method should serve as a useful tool for pharmacokinetic studies of OXC and NOC.

Determination of oxycodone in human plasma by high-performance liquid chromatography with electrochemical detection.

Determination of oxycodone in human plasma by high-performance liquid chromatography with electrochemical detection.

High Performance Liquid Chromatography (HPLC) determination of oxycodone in human plasma after oral, rectal and intravenous routes

High Performance Liquid Chromatography (HPLC) determination of oxycodone in human plasma after oral, rectal and intravenous routes

Determination of oxycodone in human plasma by high-performance liquid chromatography with electrochemical detection

Determination of oxycodone in human plasma by high-performance liquid chromatography with electrochemical detection

Determination of Oxycodone in Plasma and Identification of a Major Metabolite

An electron-capture GLC method is described for oxycodone and its major metabolite, noroxycodone, in plasma and urine. The method involves extraction of the two substances into benzene-isopropanol at pH 10.4, followed by back-extraction into 0.1 N HC1. The acid phase is washed with hexane and made alkaline prior to reextraction into benzene-isopropanol. The solvent is removed by evaporation, and the heptafluorobutyryl derivatives of the test substances are formed. After removal of excess reagent, oxycodone and noroxycodone are quantitated by GLC. The characteristics of both substances, with respect to plasma levels in dogs and analgesic activity in mice, are reported. Isolation of noroxycodone from human urine and its identification by TLC, GLC, and mass spectrometry are described.

Determination of Oxycodone and a Major Metabolite in Urine by Electron-Capture GLC

An electron-capture gas chromatographic procedure has been developed for the analysis of oxycodone In human urine, using naloxone as Internal standard. A major metabollte, tentatively identified as oxymorphone, was found to be excreted in conjugated form. From 33-61% of a single oxycodone dose was excreted in the 2n-hour urine of two subjects as free (13-19%) and conjugated oxycodone (7-29%) and conjugated oxymorphone (13-14%). A second metabolite was observed by thin-layer chromatography, but was not identified.