Potency, loss

Swart et al have demonstrated the stability of neomycin hydrochloride in aqueous solution over the pH range 2-9293. Further investigations by Simone and Popino298 confirmed the aqueous stability at 23°C but at 45°C potency losses of up to 94% were noted over a period of 2 years with solutions in the pH range 4-8. 

Where stability data show a trend toward potency loss or degradant increase under accelerated conditions, it is recommended that historical accelerated stability data from a representative prechange batch be sub-... 

Where stability data show a trend towards potency loss or degradant increase under accelerated conditions, it is recommended that historical accelerated stability data from a representative prechange batch be submitted for comparison. It is also recommended that under these circumstances, all available long-term data on test batches from ongoing studies be provided in the supplement. Submission of historical accelerated and available long-term data would facilitate review and approval of the supplement. 

An additional general method to reduce bypass is through vacuum deaeration. Miller9 performed experiments on a low-density active blend with and without vacuum deaeration, while holding all other parameters constant, and quantified the bypass for each trial. With the vacuum deaeration engaged, the bypass rate was 2% as compared to the control rate of over 20%. He also observed that the powder feed was uneven and the compact quality was not uniform. Most units are equipped with this capability and it should be considered to minimize bypass for low-dose products. However, vacuum deaeration can cause potency loss, unless the collected material is recirculated to the feed system. 

Once a sample larger than 3x is collected, a question remains as to what to do with that sample prior to assay. The withdrawn draft guidance ANDAs Blend Uniformity Analysis recommends sample sizes l-3x to be collected, but that the sample weight tested (assayed) should be equivalent to the dosage used. Unfortunately any subdivision of the sample is likely to induce either potency losses or segregation,. so the logistics of how to subdivide such a sample remains a challenge. 

A 5% potency loss from the initial assay value of a batch... 

Using the same test solutions, both photometric and agar diffusion assays with Staphylococcus aureus and the colorimetric assay of Jones did not show significant potency loss. 

The most easily understood and most studied form of drug instability is the loss of drag through a chemical reaction resulting in a reduction of potency. Loss of potency is a well-recognized cause of poor product quality. 

If you arc concerned with achieving the least potency loss, it is best to store your marijuana, unclcancd, in an airtight container in a dark, cool place. Since it takes a considerable amount of time for the potency to decrease, this will give you the option of not smoking certain marijuana for a period of time and then returning to it assured that its potency is undiminished. ... 

Grayish-white powder Very bitter taste. Sol in water alcohol. Practically insol in ether, chloroform, acetone. Stable in acid soln unstable in alkaline solns. Potency loss probably due to transformation of bacitracin A to bacitracin F, latter having little antimicrobial activity. 

Minute crystals from ale. Sol in water (1 g/15 ml), methanol. Less sol in ethanol. Practically insol in ether acetone benzene, chloroform. Aq solns are neutral may acquire a yellow discoloration without apparent potency loss. One of the ingredients of palerot (Pelerol). 

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