Diflunisal (MK-647) is a salicylate derivative with nonsteroidal anti-inflammatory and uricosuric properties, which is used alone as an analgesic and in rheumatoid arthritis patients. The mechanism of action of diflunisal is as a Cyclooxygenase (COX) Inhibitor.

Administration of increasing doses of Diflunisal to rats shows that the effect of the dose on the pharmacokinetics of Diflunisal is quite complicated. The plasma concentrations of Diflunisal decline exponentially with time, albeit with a half-life that increases with increasing dose. The CL_P is reduced considerably when the dose increases from 3 to 10 mg/kg and then remains relatively constant over the dose range of 10 to 60 mg/kg. Diflunisal has been shown to be highly bound to rat plasma protein and dependent on concentration. The fraction of unbound Diflunisal is increased about 10-fold over the concentration range of 5 to 300 μg/mL^[1]. Diflunisal exhibits activity after oral administration with potency about 25 times greater than that of aspirin, about 3 times that of glafenine and twice that of zomepirac^[2].

上海金畔生物科技有限公司 has not independently confirmed the accuracy of these methods. They are for reference only.

250.20

C₁₃H₈F₂O₃

22494-42-4

Room temperature in continental US; may vary elsewhere.

DMSO : 50 mg/mL (199.84 mM; Need ultrasonic)

请根据产品在不同溶剂中的溶解度选择合适的溶剂配制储备液；一旦配成溶液，请分装保存，避免反复冻融造成的产品失效。
储备液的保存方式和期限：-80°C, 6 months; -20°C, 1 month。-80°C 储存时，请在 6 个月内使用，-20°C 储存时，请在 1 个月内使用。

请根据您的实验动物和给药方式选择适当的溶解方案。以下溶解方案都请先按照 In Vitro 方式配制澄清的储备液，再依次添加助溶剂：

——为保证实验结果的可靠性，澄清的储备液可以根据储存条件，适当保存；体内实验的工作液，建议您现用现配，当天使用； 以下溶剂前显示的百
分比是指该溶剂在您配制终溶液中的体积占比；如在配制过程中出现沉淀、析出现象，可以通过加热和/或超声的方式助溶

• 1.

  请依序添加每种溶剂： 10% DMSO    40% PEG300    5% Tween-80    45% saline

  Solubility: ≥ 2.5 mg/mL (9.99 mM); Clear solution

  此方案可获得 ≥ 2.5 mg/mL (9.99 mM，饱和度未知) 的澄清溶液。

  以 1 mL 工作液为例，取 100 μL 25.0 mg/mL 的澄清 DMSO 储备液加到 400 μL PEG300 中，混合均匀；向上述体系中加入50 μL Tween-80，混合均匀；然后继续加入 450 μL生理盐水定容至 1 mL。

  将 0.9 g 氯化钠，完全溶解于 100 mL ddH₂O 中，得到澄清透明的生理盐水溶液

• 2.

  请依序添加每种溶剂： 10% DMSO    90% corn oil

  Solubility: ≥ 2.5 mg/mL (9.99 mM); Clear solution

  此方案可获得 ≥ 2.5 mg/mL (9.99 mM，饱和度未知) 的澄清溶液，此方案不适用于实验周期在半个月以上的实验。

  以 1 mL 工作液为例，取 100 μL 25.0 mg/mL 的澄清 DMSO 储备液加到 900 μL玉米油中，混合均匀。

• [1]. Lin JH, et al. Dose-dependent pharmacokinetics of diflunisal in rats: dual effects of protein binding and metabolism. J Pharmacol Exp Ther. 1985 Nov;235(2):402-6.

  [2]. Winter CA, et al. Analgesic activity of diflunisal [MK-647; 5-(2,4-difluorophenyl)salicylic acid] in rats with hyperalgesia induced by Freund’s adjuvant. J Pharmacol Exp Ther. 1979 Dec;211(3):678-85.

  [3]. Cappon GD, et al. Relationship between cyclooxygenase 1 and 2 selective inhibitors and fetal development when administered to rats and rabbits during the sensitive periods for heart development and midline closure. Birth Defects Res B Dev Reprod Toxicol. 2003 Feb;68(1):47-56.

Rats^[1]

For the study of dose dependency, Diflunisal is administered by i.a. injection in doses of 3, 10, 30 and 60 mg/kg (1.5, 5, 15 and 30 mg/mL dosing solution in 0.1 M NaHCO₃). The infusion studies consist of a bolus injection of Diflunisal followed immediately by a 7-hr infusion at a constant rate. Seven groups of rats are included in the infusion studies. The loading doses used are 2, 3, 5, 10, 25, 50 and 80 mg/kg and their corresponding infusion rates are 3, 4.5, 9, 18, 36, 72 and 144 μg/min (0.576 mL/hr of seven different dosing solutions: 0.31, 0.47, 0.94, 1.88, 3.75, 7.5 and 15 mg/mL in 0.1 M NaHCO₃). Blood samples are collected serially at appropriate times for the dose-dependency studies, but collected hourly for the infusion studies. Plasma is obtained immediately by centrifugation of blood samples and extracted with acetonitrile and then frozen (-20°C) until assay^[1].

上海金畔生物科技有限公司 has not independently confirmed the accuracy of these methods. They are for reference only.

• [1]. Lin JH, et al. Dose-dependent pharmacokinetics of diflunisal in rats: dual effects of protein binding and metabolism. J Pharmacol Exp Ther. 1985 Nov;235(2):402-6.

  [2]. Winter CA, et al. Analgesic activity of diflunisal [MK-647; 5-(2,4-difluorophenyl)salicylic acid] in rats with hyperalgesia induced by Freund’s adjuvant. J Pharmacol Exp Ther. 1979 Dec;211(3):678-85.

  [3]. Cappon GD, et al. Relationship between cyclooxygenase 1 and 2 selective inhibitors and fetal development when administered to rats and rabbits during the sensitive periods for heart development and midline closure. Birth Defects Res B Dev Reprod Toxicol. 2003 Feb;68(1):47-56.