For the quantification of flurbiprofen in rat plasma, a simple UPLC-MS/MS method with high sensitivity and short retention time for flurbiprofen was developed and validated using specific parameters. Etodolac was used as internal standard. The transitions (precursor to the product) of flurbiprofen and internal standard were obtained using the electrospray ionization in the negative ion multiple reaction monitoring mode, 243.2 → 199.2, 286.2 → 212.1, respectively. For chromatographic separation, C18 column was used for the stationary phase and gradient elution was used for the mobile phase. This mobile phase consisted of a methanol (A) and a 5 mM ammonium formate solution (B), which varied at a flow rate of 0.4 mL/min. For flurbiprofen, LLOQ was determined as 5 ng/mL. Quantification of flurbiprofen in the rat plasma with a linear calibration curve of 5–5000 ng/mL (r > 0.9991 for plasma) is possible with a retention time of 1.89 min. The total analysis time of the method was 3 min. The proposed method was validated. The intraday and inter-day precision (RSD%) and accuracy (RE%) were within 10% in all cases for flurbiprofen. The stability of flurbiprofen was evaluated under conditions such as short-term, long-term, autosampler and freeze/thaw. After method validation, flurbiprofen was succesfully quantified in real rat plasma samples.

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一种测定大鼠血浆中氟比洛芬的灵敏 UPLC-MS/MS 方法：在实际样品中的应用

对于大鼠血浆中氟比洛芬的定量，开发了一种简单的 UPLC-MS/MS 方法，该方法对氟比洛芬具有高灵敏度和短保留时间，并使用特定参数进行了验证。依托度酸用作内标。在负离子多反应监测模式下，使用电喷雾电离获得氟比洛芬和内标的离子对（前体到产物），分别为 243.2 → 199.2、286.2 → 212.1。对于色谱分离，固定相使用C18柱，流动相使用梯度洗脱。该流动相由甲醇 (A) 和 5 mM 甲酸铵溶液 (B) 组成，流速为 0.4 mL/min。对于氟比洛芬，LLOQ 确定为 5 ng/mL。大鼠血浆中氟比洛芬的定量分析具有 5–5000 ng/mL 的线性校准曲线（血浆 r > 0.9991），保留时间为 1.89 分钟。该方法的总分析时间为 3 min。所提出的方法得到了验证。氟比洛芬的日内和日间精度 (RSD%) 和准确度 (RE%) 均在 10% 以内。在短期、长期、自动进样器和冻融等条件下评估氟比洛芬的稳定性。方法验证后，氟比洛芬在真实大鼠血浆样品中成功定量。氟比洛芬的日内和日间精度 (RSD%) 和准确度 (RE%) 均在 10% 以内。在短期、长期、自动进样器和冻融等条件下评估氟比洛芬的稳定性。方法验证后，氟比洛芬在真实大鼠血浆样品中成功定量。氟比洛芬的日内和日间精度 (RSD%) 和准确度 (RE%) 均在 10% 以内。在短期、长期、自动进样器和冻融等条件下评估氟比洛芬的稳定性。方法验证后，氟比洛芬在真实大鼠血浆样品中成功定量。