USP盐酸米诺环素溶出度测定

灵兰1

如题，对于USP盐酸米诺环素溶出度项下计算想跟各位同仁讨论一下。
药典原文涉及计算部分的摘录如下：

Standard stock solution: 0.11 mg/mL of USP Minocycline Hydrochloride RS in Medium

Standard solutions: Dilute the Standard stock solution with Medium to obtain solutions with final concentrations of 0.088 mg/mL, 0.0528 mg/mL, 0.0352 mg/mL, 0.022 mg/mL, and 0.0176 mg/mL.

Sample solution: dissolution solution

Injection size: 20 μL for the 4 and 24 h time points; 50 μL for the 48 and 72 h time points

Analysis: Construct a calibration curve for each sampling interval by plotting the concentration of the

Standard solutions versus peak area. Calculate the slopes and y-intercepts using linear regression analysis.

Calculate the release rate of minocycline:

Resulti = [(rUi − yi)/Si] × 10/( i × W × A)

i =sampling time, 4, 24, 48, 72 h

rUi=peak response from each of the Standard solutions at time i

yi =y-intercept of the calibration curve at sampling time i

Si =slope of the calibration curve at sampling time i

W =weight of the sample (mg)

A =amount of minocycline in the sample (mg/mg of sample) as determined in the Assay

说明：溶出介质体积10ml，

Tolerances

Time (h)   Release Rate (μg/h) Average of 6 Measurements

0–4       NLT 25

4–24      NLT 1.0

24–48     NLT 0.2

48–72     NLT 0.05

具体溶出内容与计算相关性不大，未摘录，如有需要可以提供。

[size=16.6667px]问题：1 按照说明，计算公式与i时间的溶出液没有关系吗？（溶出的样品溶液，[size=16.6667px]Sample solution没参与计算[size=16.6667px]）；

[size=16.6667px]            2 如果公示中[size=16.6667px]rUi写错，实为[size=16.6667px]Sample solution的峰面积，这个计算最后的单位也无法得到ug/h?

[size=16.6667px]            3 不同时间进样体积不一致，这种不一致也未在计算公式中体现出来。

[size=16.6667px]本人非常困惑，还请广大同仁指点指点，谢谢。