Some antibiotics can be used in very high concentrations as chemotherapies. Because previous studies support the use of Valproic Acid (VPA) as a chemotherapeutic agent, it is safe to assume that lower concentrations of the drug would exhibit antimicrobial activity.
During our study, we collected data that supports this as progressively lower concentrations generally exhibited higher antimicrobial activity.
One challenge we experienced was in creating our 100 uM stock solution. The Valproic Acid (VPA) we received came as a salt, and to achieve this concentration, we had to first dilute 0.1662 g of VPA salt into 1000 uL of DMSO to create a 1M super super super stock, then dilute this stock down 3 times at a 1:10 ratio to reach our final 100 uM stock solution.
This whole process opened up lots of room for error. Measuring out exactly 0.1662 grams is difficult to do accurately. Also, the VPA salt may not have fully dissolved in the DMSO and each subsequent dilution may have perpetuated that error further.
Future studies should experiment with different approaches of diluting VPA accurately to minimize error, as well as experiment with different methods of administering the drug (e.g. using the salt on its own, rather than a salt solution).
Why do you think the lower concentration of Valproic Acid was most successful?
Some antibiotics can be used in very high concentrations as chemotherapies. Because previous studies support the use of Valproic Acid (VPA) as a chemotherapeutic agent, it is safe to assume that lower concentrations of the drug would exhibit antimicrobial activity.
During our study, we collected data that supports this as progressively lower concentrations generally exhibited higher antimicrobial activity.
Are there any other further experiments you could follow up with other than testing with lower concentrations?
One challenge we experienced was in creating our 100 uM stock solution. The Valproic Acid (VPA) we received came as a salt, and to achieve this concentration, we had to first dilute 0.1662 g of VPA salt into 1000 uL of DMSO to create a 1M super super super stock, then dilute this stock down 3 times at a 1:10 ratio to reach our final 100 uM stock solution.
This whole process opened up lots of room for error. Measuring out exactly 0.1662 grams is difficult to do accurately. Also, the VPA salt may not have fully dissolved in the DMSO and each subsequent dilution may have perpetuated that error further.
Future studies should experiment with different approaches of diluting VPA accurately to minimize error, as well as experiment with different methods of administering the drug (e.g. using the salt on its own, rather than a salt solution).