It was most likely due to human error incorrectly pipetting either the bacteria or the compound in. In the future, it would probably be best to control for this by asking one person to pipette it for all the trials. Of course, due to our time constraints, this would probably not be possible, but it would lead to better results most likely.
If you were to actually repeat your experiment again would you change anything about your procedure to increase the chance of reaching conclusive results?
For the 1:1.32 dilution we ran, it would be useful to have one person pipette to limit any error caused by different pipetting methods. Also, it would be useful to make sure that the serial dilution we created is actually true to what we calculated. I feel like these two measures would have at least allowed for more conclusive results.
The first thing would be having one person pipette. This would control for any differences caused by different group member’s pipetting methods. Secondly, for the serial dilution, it would be nice to make sure that the pipetting was carried out correctly according to our actual calculations using a spectrophotometer. Lastly, if we had more time, running a trial looking at the bacteriostatic and bactericidal effects of our compound could have led to us having a more conclusive and definite results.
Yes, definitely! Once we figure out the concentrations that are hits (after conducting multiple trials), we would look into lower concentrations that still yield effective results.
With your future directions, and as you believe that the issues arose from issues with different pipette techniques between group members, how would you go about future investigations into your compound, especially with your result indicating potential issues with the water being used. Unless I misunderstood and the water is not being used as a growth media for the S. Typhimurium, which would bring up other issues concerning the absorbance measurements for your compound.
Great question! There wasn’t quite a potential issue with the water being used. The issue lies in incorrect pipetting of the bacteria into the well filled with our positive control, DI water. The reason we used water as a positive control is to control for any issues that may have arose from using water to dilute 4-HBITC. To clarify, our growth media is M9 minimal media for the S. Typhimurium. There would probably not be any issues concerning the absorbance measurements because we did not pipette growth media into the wells, we just pipetted the bacteria. Future investigations with our compound would involve repeating what we’ve already done and identifying the bacteriostatic and/or bactericidal properties of 4-HBITC.
In your opinion, what do you think led to one of the results being inconclusive? Do you believe it was due to human error, dilution factor, etc…?
It was most likely due to human error incorrectly pipetting either the bacteria or the compound in. In the future, it would probably be best to control for this by asking one person to pipette it for all the trials. Of course, due to our time constraints, this would probably not be possible, but it would lead to better results most likely.
If you were to actually repeat your experiment again would you change anything about your procedure to increase the chance of reaching conclusive results?
For the 1:1.32 dilution we ran, it would be useful to have one person pipette to limit any error caused by different pipetting methods. Also, it would be useful to make sure that the serial dilution we created is actually true to what we calculated. I feel like these two measures would have at least allowed for more conclusive results.
The first thing would be having one person pipette. This would control for any differences caused by different group member’s pipetting methods. Secondly, for the serial dilution, it would be nice to make sure that the pipetting was carried out correctly according to our actual calculations using a spectrophotometer. Lastly, if we had more time, running a trial looking at the bacteriostatic and bactericidal effects of our compound could have led to us having a more conclusive and definite results.
Since you had an inconclusive result, do you believe it was due to the dilutions?
See above!
Would you try to include various dilutions in future experiments? Do you know how this would affect the results?
Yes, definitely! Once we figure out the concentrations that are hits (after conducting multiple trials), we would look into lower concentrations that still yield effective results.
With your future directions, and as you believe that the issues arose from issues with different pipette techniques between group members, how would you go about future investigations into your compound, especially with your result indicating potential issues with the water being used. Unless I misunderstood and the water is not being used as a growth media for the S. Typhimurium, which would bring up other issues concerning the absorbance measurements for your compound.
Great question! There wasn’t quite a potential issue with the water being used. The issue lies in incorrect pipetting of the bacteria into the well filled with our positive control, DI water. The reason we used water as a positive control is to control for any issues that may have arose from using water to dilute 4-HBITC. To clarify, our growth media is M9 minimal media for the S. Typhimurium. There would probably not be any issues concerning the absorbance measurements because we did not pipette growth media into the wells, we just pipetted the bacteria. Future investigations with our compound would involve repeating what we’ve already done and identifying the bacteriostatic and/or bactericidal properties of 4-HBITC.