Electronic Supplementary Material (ESM)
Investigation on the interaction between anthracyclines and DNA in the presence
of paclitaxel by resonance light scattering technique
Zhanguang Chen a,*, Sihua Qiana, Xi Chenb, Junhui Chenc, Guomin Zhanga, Guihua
Zenga
a
Department of Chemistry, Shantou University, Shantou 515063, China
Guangdong Pharmaceutical University, Guangzhou 510006, China
c
Department of Radiology, Peking University Shenzhen Hospital, Shenzhen 518036,
China
b
*Corresponding author at: Department of Chemistry, Shantou University, Shantou,
515063, China. Tel: + 86 75482903330. Fax: + 86 75482902767.
E-mail address: kqlu@stu.edu.cn (Z. Chen).
Effect of reagents adding order on RLS intensity
In order to investigate the effect of reagents adding order, we changed the adding order of reagents
as follows: DNA-anthracyclines-PTX, DNA-PTX-anthracyclines and anthracyclines-PTX-DNA.
The results showed that the adding order could affect the analytical systems in varying degrees.
The effects of reagents adding order on anthracyclines-DNA-PTX systems was displayed in
Supplementary material SI-1. It can be seen that the addition order of reagents had a dramatical
effect on the RLS intensities of the analytical system. For DOX-DNA-PTX system, the adding
order of DNA-DOX-PTX produced the strongest RLS intensity. However, the DNA-PTX-DOX
adding order produced a 10.29% lower RLS intensity and the PTX-DOX-DNA order a 30.84%
lower intensity. For EPI-DNA-PTX system, the adding order of DNA-EPI-PTX produced the
strongest RLS intensity. However, the DNA-PTX-EPI adding order produced a 25.70% lower
RLS intensity and the PTX-EPI-DNA order a 40.95% lower intensity. As to MIT-DNA-PTX
system, the adding order of DNA-MIT-PTX produced the strongest RLS intensity; the
DNA-PTX-MIT adding order produced a 3.51% lower RLS intensity and the PTX-MIT-DNA
order a 2.31% lower intensity.
Effect of anthracyclines concentrations on RLS intensities
The effects of anthracyclines concentrations on RLS intensities were studied by fixing PTX
concentration at 18 μg mL−1. As depicted in Supplementary material SI-2a, it can be seen that
when DOX concentration was in the range of 15-20 μg mL−1, the RLS intensities of DOX-DNA
system were strong and stable. Besides, the RLS intensity at DOX concentration 18 μg mL−1
reached maximum. As to DOX-DNA-PTX system, the RLS intensities of it reached maximum
when DOX concentration was 22 μg mL−1. Herein, we defined Cmax as the concentration of
anthracyclines at which the RLS intensity of anthracyclines-DNA reached maximum. As can be
seen from Fig. 5a, the Cmax of DOX was increased by the addition of PTX. The increased C max of
DOX may reveal an increased maximum tolerated dose (MTD) of DOX.
Supplementary material SI-2b displayed the effect of EPI concentration on RLS intensities.
According to the figure, the RLS intensities of EPI-DNA system were strong and stable when EPI
concentration was in the range of 9.0-15 μg mL−1, and the RLS intensity reached maximum when
EPI concentration was 12 μg mL−1. With the addition of PTX into EPI-DNA system, the RLS
intensities of EPI-DNA system were increased. When EPI concentration was 12 μg mL−1, the
intensity reached maximum and then was decreased with the increasing EPI concentration. The
figure showed that the Cmax of EPI was constant after the addition of PTX, thus a constant MTD of
EPI.
Supplementary material SI-2c showed that when MIT concentration was in the range of 6.0-12
μg mL−1, the RLS intensities of MIT-DNA system were strong and stable, and the RLS intensity at
MIT concentration 9.0 μg mL−1 reached maximum. What’s more, at MIT concentration 9.0 μg
mL−1, the RLS intensity of MIT-DNA-PTX system reached maximum and then decreased with the
increasing MIT concentration. According to the figure, with the addition of PTX, the Cmax of MIT
was constant. Therefore, the MTD of MIT may be constant after the addition of PTX.
Addition order
RLS intensity (%)
DNA+DOX+PTX
DNA+PTX+DOX
PTX+DOX+DNA
DNA+EPI+PTX
DNA+PTX+EPI
PTX+EPI+DNA
DNA+MIT+PTX
DNA+PTX+MIT
PTX+MIT+DNA
100
89.71
69.16
100
74.30
59.05
100
96.49
97.69
SI-1 Effect of reagents addition orders on RLS intensities of anthracyclines-DNA-PTX systems.
Conditions: PTX, 18 µg mL−1; DOX, 18 µg mL−1; EPI, 12 µg mL−1; MIT, 9.0 µg mL−1; DNA, 2.0
µg mL−1; pH = 7.4.
SI-2 Effect of drugs concentrations on the RLS intensities of DOX-DNA-PTX system (a),
EPI-DNA-PTX system (b) and MIT-DNA-PTX system (c). Conditions: PTX, 18 μg mL−1; ctDNA,
2.0 μg mL−1; pH 7.4.