Simplex maximization of the correlation coefficient for DNA sizing analysis by capillary electrophoresis

Area of Science:

• Analytical Chemistry
• Biochemistry
• Molecular Biology

Background:

• Capillary electrophoresis (CE) is crucial for DNA molecule separation in polymeric solutions.
• Optimizing CE variables like polymer concentration and electric field is time-consuming and can lead to suboptimal results.

Purpose of the Study:

• To apply a simplex chemometric method for simultaneous optimization of CE variables.
• To maximize the correlation coefficient (r²) of mobility (μ) versus base pair (bp) for DNA fragments.
• To enhance the precision and accuracy of DNA fragment size determination.

Main Methods:

• Utilized a simplex method, a chemometric technique for multi-variable optimization.
• Separated DNA fragments ranging from 75 to 4072 base pairs (bp).
• Analyzed the logarithmic plot of mobility (μ) versus base pair (bp) to assess separation efficiency.

Main Results:

• The simplex method identified optimal conditions yielding high correlation coefficients (r² > 0.98).
• Specific optimization (vertex 21) resulted in the highest resolution for DNA fragment separation.
• For fragments between 201 and 2036 bp, r² reached 0.992 with low relative standard deviation (<0.2%).
• Inclusion of an internal standard further improved the precision of DNA fragment sizing.

Conclusions:

• The simplex method offers an efficient approach to optimize CE for DNA fragment analysis.
• This optimized method provides accurate and precise DNA sizing, crucial for applications like PCR fragment analysis.
• Further precision gains are achievable with internal standards in CE-based DNA analysis.