ciprofloxacin powder from himedia states that assay = 98%(HPLC). does this 98% refers to potency of the drug. how should i substitute this value in the following formula for antibiotic stock solution
W=C*V/P.
I would take this value to mean that the drug, Ciprofloxacin, has been tested using HPLC and found to be 98% pure, by this method. This implies that up to 2% of the material examined via HPLC was not pure Ciprofloxacin. However, this does not necessarily inform about the POTENCY of the drug, since that will depend not only on its purity, but the salt used, the vehicle in which it is dissolved or suspended, its biological half-life and the biological system to which it is administered. Also, whether it is fresh or old stock, whether it has been stored appropriately, and on its known stability/shelf-life.
It is about purity, as stated Zoë.
For calculations: the real concentration Cr=0,98*m/V. m - mass of the standard recorded from the scale, V- volume of solvent.
Regards
G
Yes and no! As per USP guidelines on numbering (general chapters) the 98% should be expressed as 98.0% for each lot (decimal points!). It means there is 2.0% other stuff like moisture (unless on an anhydrous basis) or organic related substances.
The drug product (what you manufacture with this API) has to be analysed by a validated analytical method (usually chromatography like HPLC as per ICH Q2). In addition you have to monitor the related substances (could be different) as per ICH Q3.
For nearly all substances recovered from nature, it is almost impossible to attain 100% purity. The 98% (which technically is written 98.0%) is the percentage composition of the drug (ciprofloxacin) in the package. However, this is not the strength of the drug as such. Good luck
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering
- Powders