Bradford dye absorption spectrum question?

Click For Summary

Discussion Overview

The discussion revolves around the optimal wavelength for measuring protein concentration using Bradford dye, specifically focusing on the significance of 595 nm as indicated in the absorption spectra. Participants explore the reasoning behind this choice, including potential connections to color theory and the characteristics of the dye's absorption properties.

Discussion Character

  • Homework-related
  • Exploratory
  • Debate/contested

Main Points Raised

  • One participant questions the clarity of the manual's explanation regarding why 595 nm is optimal, suggesting it may relate to the color wheel.
  • Another participant proposes that the wide separation of peaks between acidic and non-acidic forms of the dye could be one reason for choosing 595 nm, and mentions the potential importance of taking ratios in absorption measurements.
  • A third participant echoes the inquiry about providing hints and emphasizes the clarity of the spectra in addressing the question.
  • A participant expresses a strong interest in researching the optimal wavelength for measuring the blue color associated with the dye.
  • There is a reminder about the forum guidelines regarding homework questions, indicating that such inquiries should be posted in the appropriate section.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the reasons for choosing 595 nm, and there is a mix of opinions regarding the appropriateness of the original question as a homework inquiry.

Contextual Notes

Some participants express uncertainty about the procedure and the implications of their suggestions, indicating a lack of familiarity with the topic. There are references to forum guidelines that suggest a need for clarity on whether the discussion is appropriate for the main technical forums.

fightboy
Messages
25
Reaction score
0
https://www.physicsforums.com/attachments/74483 https://www.physicsforums.com/attachments/74483
Based in the absorption spectra above, why is 595 nm the best wavelength to measure protein concentration with Bradford dye (Hint: there are two important reasons for choosing 595).
I think it has something to do with the color wheel but honestly the explanation in the manual is very unclear. Can someone try to explain it to me?
 

Attachments

  • image.jpg
    image.jpg
    52 KB · Views: 612
Biology news on Phys.org
fightboy said:
https://www.physicsforums.com/attachments/74483 https://www.physicsforums.com/attachments/74483
Based in the absorption spectra above, why is 595 nm the best wavelength to measure protein concentration with Bradford dye (Hint: there are two important reasons for choosing 595).
I think it has something to do with the color wheel but honestly the explanation in the manual is very unclear. Can someone try to explain it to me?

You are asking a question but provide a hint. Is this homework?

You had to make me read up on the local roolz: "Helpers: don't provide the entire solution". [ https://www.physicsforums.com/threads/guidelines-for-students-and-helpers.686781/ ]

I haven't done anything like that, so mind that maybe I'm not helping at all because I could be misunderstanding the procedure.

FWIW, but after looking around the web I'm guessing the wide separation of peaks between acidic and non-acidic forms of the dye is part of one of the two reasons. The other reason could be related to that, by the quantitative use of the absorption measurements, taking ratios (which may or may not be called a "modified" assay - here is where I would urge caution based on my unfamiliarity with the subject).

Now why would I make those two guesses?
 
fightboy said:
Based in the absorption spectra above, why is 595 nm the best wavelength to measure protein concentration with Bradford dye (Hint: there are two important reasons for choosing 595).

It's pretty clear from your spectra. Echoing Torbjorn, why are you providing 'hints'?
 
  • Like
Likes   Reactions: Medicol
I have an unquenchable thirst for chemical research over the best or optimal wavelength to measure the blue color represented as a global maximum. :DD
 
Last edited:
In case this is homework:

Since I posted my previous comment, I have noticed that (not attempted) homework has another place.

"Homework Guidelines
  • Posts Belong in the Homework Forum
Any and all high school and undergraduate homework assignments or textbook style exercises for which you are seeking assistance are to be posted in the appropriate forum in our Homework & Coursework Questions area--not in blogs, visitor messages, PMs, or the main technical forums. This should be done whether the problem is part of one's assigned coursework or just independent study. The reason for this is that the scientific and mathematical sections of Physics Forums are to be reserved for discussions and not academic assistance. Since graduate level assignments are meant to be more thought provoking (and hence more worthy of discussion), graduate level questions will be allowed in the relevant part of the main section of PF, provided that the graduate student attempts the problem and shows his work."

[ https://www.physicsforums.com/threads/physics-forums-global-guidelines.414380/ ]
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 46 ·
2
Replies
46
Views
9K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 1 ·
Replies
1
Views
18K
  • · Replies 9 ·
Replies
9
Views
9K
  • · Replies 49 ·
2
Replies
49
Views
13K
  • · Replies 69 ·
3
Replies
69
Views
15K
  • · Replies 89 ·
3
Replies
89
Views
38K
  • Sticky
  • · Replies 0 ·
Replies
0
Views
23K
  • Sticky
  • · Replies 0 ·
Replies
0
Views
18K