Referee 1's review:

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N.B. These are the comments made by the referee when reviewing an earlier version of this paper. Prior to publication the manuscript has been revised in light of these comments and to address other editorial requirements.
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"Sequence Effect of Self-Assembling Peptides on the Complexation and In Vitro Delivery of the Hydrophobic Anticancer Drug Ellipticine" by Shan-Yu Fung, Hong Yang, and Pu Chen.

The authors probed the effect of peptide sequence on the complex formation and its anticancer activity in vitro. The work is good. This work provides some information for peptide designers in the development of self-assembling peptide-based delivery of hydrophobic anticancer drugs.

The manuscript in its current form is not publishable in PLoS ONE for the following reasons; 1) the manuscript is full of grammatical errors or the experiments, statistics, and other analyses performed to a sufficient technical standard and requires serious editing and revision. Several paragraphs particularly in the result section are very difficult to follow,

1 A more detailed to Purification
the paper is based the peptides, the accurate purification of peptide is need to reader, not a word "crude",the HPLC and MS to the peptides should be as a supplement files to the paper.

Anyway, the peptide concentration with 0.5, 0.2 and 0.04mg/ml

2 A more detailed to AFM

the AFM figure obtained from the "Without further purification peptide":
In the paper 3.4 AFM, the self-assembling peptides form to the nanofiber or aggregate to the nanoparticals need a few times, the paper is not to show the reader.

From Figure 2ABC, it may be not conclude the peptide self-assembling or not because the peptides are impurity.

3 "Surface tension measurements"
"The dynamic surface tension of fresh peptide solutions was measured over a
period of 2 h using the Axisymmtratic Drop Shape Analysis-Profile (ADSA-P) technique."
The figure 3a is very good.
Strictly, a blank to the figure should be added.
If inserted a figure about the change of the water volumes Via time, may be perfect. After all, the 2 Hours is very long time to drop water.

4 "Dynamic Light Scattering"
"The dimension of the peptide assemblies (0.5 mg/mL) and the complexes from
the peptide-ellipticine suspensions was investigated on a Zetasizer Nano ZS (Malvern
Instruments, Worcestershire, U.K.) with appropriate viscosity and refractive index
settings and the temperature was maintained at 25 {degree sign}C during the measurement. A quartz microcell (45uL) with a 3 mm light path was used."

the self-assembling peptide with impurity is very easy form to nanofibers or aggregate to the particles. From the Figure 2abc and Fig6 (a) and (b), maybe the results are very conflict to readers, if not, make clear to the results.

When used the Zetasizer Nano ZS (Malvern Instruments, Worcestershire, U.K.),
The used the software package Dispersion Technology Software 5.0 (Malvern Instruments, Worcestershire, U.K.).

There is a "cummulants result" with PDI.
The paper is better to show the readers how much the "PDI" to the peptides?
The paper is better to show the readers how to deal with the samples when obtained to the "DLS"?

5 Scanning Electron Microscopy (SEM)

"The SEM sample was prepared by depositing 10uL of the peptide-ellipticine suspensions on a freshly cleaved mica surface."

Figure 7 seem like very good, it is very interesting that it is not obtained from the nanofibers from the SEM but to the AFM.

Maybe there is a question to the prepared sample.

6 In vitro cell viability studies
"For each type of cell, 200 uL of the cell suspensions were added into each well of a clear, flat bottom 96-well plate (Costar) and incubated overnight. 50 uL of the treatments (including the complexes and control samples) were then added to the wells each containing 150 uL of fresh culture media. The plates were incubated for 48 h prior to perform the cell viability assay.

"The 16 peptide controls have some toxicity to the cells, causing the decrease of viability to the values between 0.6 and 0.8."

Are the peptides that EAK-II and EAK-IV toxity to the cell?

The paper is better to show the readers how much the pH of peptides water solution, then it may be explain the peptide controls have some toxicity to the cell.