Microchip Electrophoresis

Round 1

Reviewer 1 Report

Accept in present form

Author Response

I thank the reviewer for accepting the entry.

Reviewer 2 Report

Dear author,

This review provided a comprehensive review of microfuidic-based electrophoresis technologies. Proper background knowledge and state-of-the-art reviews were discussed. In overall, this is a well structured article. Some minor comments were suggested here for your reference to enhance some aspects for the readers.

1. In the article, many microfluidic-based electrophoresis technologies were discussed. However, the major advantages of microfluidic-based approaches over traditional bulk capillary electrophoresis were not really addressed. This fundamental comparison should be addressed. 
2. If different molecular weight macro-molecules can migrate at different velocities while conducting electrophoresis, why microfluidic-based shorter channel lengths can provide advantages? Isn't longer channel like bulk electrophoresis providing better resolution?
3. Could the author address the pros and cons of each cited technology specifically? By doing this, the readers would be able to understand more and compare between different options.

Author Response

I thank the reviewer for the comments and for accepting the paper. The minor suggestions have been applied in the paper and are listed below

1. In the article, many microfluidic-based electrophoresis technologies were discussed. However, the major advantages of microfluidic-based approaches over traditional bulk capillary electrophoresis were not really addressed. This fundamental comparison should be addressed.

Answer: This has been addressed in the paper now and reads

“MCE offers many advantages over conventional capillary electrophoresis techniques such as integration of different separation functions onto the chip, consumption of small amounts of sample and reagents, faster analyses and efficient separations, etc. [6], [7]. A few additional functions such as sample preparation, washing, and incubation with antibodies and derivatization with dyes can be integrated on a single stamp size microchip, MCE has the potential to be adapted for portable POC and clinical diagnostics devices. Microchip electrophoresis provides separations within a minute or few seconds while capillary electrophoresis takes minutes to hours to fully resolve the components of the sample mixture. MCE also offers the integration of detection methods such as electrochemical detections, laser induced fluorescence detections and interface with mass spectrometry. As a result, MCE has been used in a variety of applications, e.g., to analyze biomolecules in blood [8], saliva [9], tear [10], dialysate [11], and islets [12].”

2. If different molecular weight macro-molecules can migrate at different velocities while conducting electrophoresis, why microfluidic-based shorter channel lengths can provide advantages? Isn't longer channel like bulk electrophoresis providing better resolution?

Answer: While this is true for capillary zone electrophoresis, but for macromolecules, gel electrophoresis is widely used for separation. Capillary gel electrophoresis can only use low voltages due to the generation of heat in the gel (and hence gel can break) and will take longer time to separate. On the other hand, microchip gel electrophoresis offers the advantage of using shorter channels and low sample volume and can apply higher voltages to achieve very fast separations. The heat dissipation is better and separation is achieved must faster before the heat can shrink the gel or break it.

3. Could the author address the pros and cons of each cited technology specifically? By doing this, the readers would be able to understand more and compare between different options.

Answer: This has been added in the text and highlighted.

Reviewer 3 Report

This review paper summarizes the microchip electrophoresis and its applications. This reviewer believes that this paper delivers useful information to researchers in related fields.

Although the manuscript is acceptable, minor spell check is required. For instance, in "Definition" second line, 'comon' should be corrected.

Author Response

I thank the reviewer for comments.

Although the manuscript is acceptable, minor spell check is required. For instance, in "Definition" second line, 'comon' should be corrected.

Answer: This has been corrected and the paper has been checked again for any corrections.

Round 2

Reviewer 2 Report

Dear author,

All the comments were addressed properly in the revised manuscript. I have no further comments of the manuscript.

Reviewer 3 Report

This manuscript is now ready for publish!