Sampling (optimization?) [Design Issues]
Dear Helmut,
Many thanks for the Excel workout and valuable info on “partial derivatives plot”.
On a second thought, can I tweak the algorithm to generate geometric progression such that the sampling is closer towards the last time point. Consider I have 18 sampling time points till 36 hours and the Cmax for my formulation is around 4 hours. I can split them in to two sets.
For pre Tmax sampling time points I will use the algorithm that generates time points in a geometric progression that are closer towards the last time point [i.e. actually the Tmax].
After this exercise, if the 18 sampling time point thus generated are put together, we will have a sampling schedule which is crowded towards the Tmax [ideal] and spacing out in a geometric progression on either sides.
I totally agree with you but, just wanted to play around a bit with the algorithm. May come in handy for ER products with Tmax around 12 hours having a zero order release/absorption profile. I tried my bit with tweaking the excel algorithm but only ended up with failure .
Thanks,
IP.
Many thanks for the Excel workout and valuable info on “partial derivatives plot”.
On a second thought, can I tweak the algorithm to generate geometric progression such that the sampling is closer towards the last time point. Consider I have 18 sampling time points till 36 hours and the Cmax for my formulation is around 4 hours. I can split them in to two sets.
- 9 sampling time points pre Tmax
- 9 sampling time points post Tmax
For pre Tmax sampling time points I will use the algorithm that generates time points in a geometric progression that are closer towards the last time point [i.e. actually the Tmax].
After this exercise, if the 18 sampling time point thus generated are put together, we will have a sampling schedule which is crowded towards the Tmax [ideal] and spacing out in a geometric progression on either sides.
❝ To keep it simple I would set the sampling interval to multiples of 15 minutes. We should have at least three sampling time points in the absorption phase and around Cmax (FDA). So I suggest to aim for five evenly spaced samples in the interval [0, 4.75] ⇒ [0, 0.95, 1.9, 2.85, 3.8, 4.75] ⇒ mround(t,0.25)
⇒ [0, 1, 2, 2.75, 3.75, 4.75]. The remaining ten sample geometrically spaced, rounded ⇒ [6.5, 8.75, 11.75, 16, 21.5, 29, 39.25, 53.25, 72].
I totally agree with you but, just wanted to play around a bit with the algorithm. May come in handy for ER products with Tmax around 12 hours having a zero order release/absorption profile. I tried my bit with tweaking the excel algorithm but only ended up with failure .
Thanks,
IP.
—
Thanks & Regards,
IP.
Thanks & Regards,
IP.
Complete thread:
- How to Define Sampling Interval eduardojmorales 2006-10-05 21:11 [Design Issues]
- How to Define Sampling Interval eduardojmorales 2006-10-05 23:16
- Soliloquy? H_Rotter 2006-10-06 13:27
- Soliloquy? eduardojmorales 2006-10-10 18:09
- Algorithm (geometric progression) Helmut 2006-10-07 21:48
- Algorithm (geometric progression) eduardojmorales 2006-10-10 18:23
- Algorithm (geometric progression) Helmut 2006-10-10 19:05
- Algorithm (geometric progression) intuitivepharma 2013-02-28 08:10
- Geometric progression in Excel Helmut 2013-02-28 13:56
- Sampling (optimization?) Helmut 2013-02-28 16:50
- Sampling (optimization?)intuitivepharma 2013-03-01 07:42
- Sampling (optimization?) SDavis 2013-03-07 10:40
- VIFs? Helmut 2013-03-07 15:50
- Sampling (optimization?) intuitivepharma 2013-03-08 12:39
- Sampling (optimization?) SDavis 2013-03-07 10:40
- Sampling (optimization?)intuitivepharma 2013-03-01 07:42
- Algorithm (geometric progression) eduardojmorales 2006-10-10 18:23
- Soliloquy? H_Rotter 2006-10-06 13:27
- How to Define Sampling Interval eduardojmorales 2006-10-05 23:16