Lornoxicam quantification in rabbit plasma by reverse phase HPLC: Optimization and application to pharmacokinetic study

Exploring the pharmacokinetics and tolerability of cyclooxygenase inhibitor ampiroxicam: a phase I study on single and multiple oral doses

Introduction: Ampiroxicam is a long-acting, non-steroidal anti-inflammatory drug that selectively inhibits human cyclooxygenase, effectively mitigating fever, pain, and inflammation. This study evaluated the drug's tolerability and pharmacokinetics to support personalized dosing strategies. Methods: The study involved healthy participants and focused on the pharmacokinetics of ampiroxicam. Plasma levels of piroxicam, a key metabolite of ampiroxicam, were measured using ultra-performance liquid chromatography. Piroxicam was chosen due to its integral role in ampiroxicam's metabolic pathway. The analytical method underwent rigorous validation to ensure precision and accuracy, addressing potential interference from endogenous plasma substances. Results: Participants received ampiroxicam in single doses (low, medium, and high) and multiple doses. Pharmacokinetic parameters, including AUC0-216, AUC0-∞, and Cmax, exhibited a dose-dependent increase. No significant differences were noted across the dosage groups, and sex-specific differences were minimal, with the exception of mean residence time (MRT) in the multiple-dose group, which appeared influenced by body weight variations. Discussion: The findings affirm the safety and efficacy of ampiroxicam across different dosing regimens, validating its clinical utility and potential for personalized medicine in the treatment of pain and inflammation.

Thiosemicarbazide functionalized carbon quantum dots as a fluorescent probe for the determination of some oxicams: application to dosage forms and biological fluids

In this study, highly fluorescent water-soluble nitrogen and sulfur doped carbon quantum dots (N, S-CQDs) were synthesized via a one-step hydrothermal process utilizing citric acid as a carbon source and thiosemicarbazide as a sulfur and nitrogen source. The obtained N, S-CQDs exhibited an intense emission band at 415 nm (λ ex = 345 nm). In the presence of either piroxicam, tenoxicam or lornoxicam, the emission band at 415 nm was significantly quenched which might be triggered due to destruction of the surface passivation layer of the N, S-CQDs. A linear correlation was found between the reduction in the fluorescence intensity of N, S-CQDs and the concentration of each drug in the ranges of 2.0-25.0 μM, 10.0-100.0 μM and 20.0-200.0 μM with correlation coefficients of more than 0.999 for all drugs. The detection limits were 0.49 μM, 1.58 μM and 4.63 μM for piroxicam, tenoxicam and lornoxicam, respectively. The effect of experimental parameters affecting the performance of the method was investigated and optimized. The developed sensor has the advantages of simplicity, time-saving, convenience and satisfactory selectivity for determination of the studied drugs in dosage forms with high % recoveries (98.86-101.69%). The method was extended for determination of piroxicam in spiked plasma with % recoveries ranging from 97.95-101.36%. The method was validated in accordance with International Council of Harmonization (ICH) standards, and the results obtained were compared statistically to those given by reported methods, indicating no significant differences in the level of accuracy and precision. The mechanism of the quenching process was studied and elucidated. The structure-activity relationship between the three drugs and the quenching efficiency was also studied and discussed.

Meloxicam quantification in rabbit plasma by RP-HPLC: optimization and application to pharmacokinetic study

Background

The goal of the proposed study was to validate a rapid, simple, an accurate, robust, and sensitive bioanalytical method for quantifying Meloxicam and Lornoxicam (as internal standard) in rabbit plasma.

Result

Limit of detection and limit of quantification for Meloxicam were found to be 0.0081 and 0.1035 μg mL−1, respectively. The bioanalysis was continued according to standard guidelines and successfully used for bioavailability studies of meloxicam after single dose administration of pure drug and the formulation in rabbit plasma. Finally, obtained results proved its simplicity and an efficiency to be applied for the therapeutic drug monitoring and bioequivalence studies.

Conclusion

Therefore, the set RP-HPLC bioanalysis is simple, convenient, and acceptable to analyze meloxicam in bulk and pharmaceutical formulations in rabbit plasma.

Graphical abstract