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. 2022 Aug 27;15(17):5926.
doi: 10.3390/ma15175926.

pH-Sensitive Polyacrylic Acid-Gated Mesoporous Silica Nanocarrier Incorporated with Calcium Ions for Controlled Drug Release

Jungwon Kong  1 , Sung Soo Park  2 , Chang-Sik Ha  1
Affiliations

pH-Sensitive Polyacrylic Acid-Gated Mesoporous Silica Nanocarrier Incorporated with Calcium Ions for Controlled Drug Release

Jungwon Kong et al. Materials (Basel). .

Abstract

In this work, polyacrylic acid-functionalized MCM-41 was synthesized, which was made to interact with calcium ions, in order to realize enhanced pH-responsive nanocarriers for sustained drug release. First, mesoporous silica nanoparticles (MSNs) were prepared by the sol-gel method. Afterward, a (3-trimethoxysilyl)propyl methacrylate (TMSPM) modified surface was prepared by using the post-grafting method, and then the polymerization of the acrylic acid was performed. After adding a calcium chloride solution, polyacrylic acid-functionalized MSNs with calcium-carboxyl ionic bonds in the polymeric layer, which can prevent the cargo from leaking out of the mesopore, were prepared. The structure and morphology of the modified nanoparticles (PAA-MSNs) were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), and N2 adsorption-desorption analysis, etc. The controlled release of guest molecules was studied by using 5-fluorouracil (5-FU). The drug molecule-incorporated nanoparticles showed different releasing rates under different pH conditions. It is considered that our current materials have the potential as pH-responsive nanocarriers in the field of medical treatment.

Keywords: 5-fluorouracil; calcium ion; drug delivery; mesoporous silica; polyacrylic acid.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Scheme 1
Scheme 1
An illustration for the preparation of Ca@MCM-41-PAA_5-FU and the releasing behavior of drug molecules in pH stimulus.
Figure 1
Figure 1
SEM images of (a,b) MCM-41, (c,d) MCM-41-TMSPM, (e,f) MCM-41-PAA, (g,h) Ca@MCM-41-PAA_5-FU.
Figure 2
Figure 2
TEM images of (a) MCM-41, (b) MCM-41-TMSPM, (c) MCM-41-PAA, and (d) Ca@MCM-41-PAA_5-FU.
Figure 3
Figure 3
FE-TEM image (a), EDS mapping (b–h) and spectra (i) of Ca@MCM-41-PAA_5-FU.
Figure 4
Figure 4
Low-angle XRD patterns of (a) MCM-41, (b) MCM-41-TMSPM, (c) MCM-41-PAA, and (d) Ca@MCM-41-PAA_5-FU.
Figure 5
Figure 5
Wide-angle XRD patterns of (a) 5-FU, (b) MCM-41_5-FU, (c) MCM-41-PAA_5-FU, and (d) Ca@MCM-41-PAA_5-FU.
Figure 6
Figure 6
TGA curves of (a) MCM-41, (b) MCM-41-TMSPM, (c) MCM-41-PAA, and (d) Ca@MCM-41-PAA_5-FU.
Figure 7
Figure 7
FT-IR spectra of (a) MCM-41, (b) MCM-41-TMSPM, (c) MCM-41-PAA, and (d) Ca@MCM-41-PAA_5-FU. (◆ C-H, ♠ C=O, ■ C=C, ▲ O-C-O, ★ H2O, ● Si-OH, → Si-O-Si).
Figure 8
Figure 8
N2 adsorption-desorption isotherms (A) and pore size distributions (B) of (a) MCM-41, (b) MCM-41-PAA and (c) Ca@MCM-41-PAA_5-FU.
Figure 9
Figure 9
DLS curves of (A), (a) MCM-41 and (b) MCM-41-PAA; (B), Ca@MCM-41-PAA_5-FU with different pH environment of (a) pH 5.4 and (b) 7.4.
Figure 10
Figure 10
In vitro 5-FU release profiles of (A) MCM-41_5-FU, (B) MCM-41-PAA_5-FU, and (C) Ca@MCM-41-PAA_5-FU with different pH environment of (a) pH 5.4 and (b) 7.4.
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References

    1. Rehkopf J.D., Barbat S.D., Goldman N.M., Samus M.A., Gold H. Environmentally responsive material to address human-system interaction in the automotive cockpit. Smart Mater. Struct. Ind. Commer. Appl. Smart Struct. Technol. 2001;4332:217–224.
    1. Basheer A.A. Advances in the smart materials applications in the aerospace industries. Aircr. Eng. Aerosp. Technol. 2020;92:1027–1035. doi: 10.1108/AEAT-02-2020-0040. - DOI
    1. Liu Y., Du H., Liu L., Leng J. Shape memory polymers and their composites in aerospace applications: A review. Smart Mater. Struct. 2014;23:023001. doi: 10.1088/0964-1726/23/2/023001. - DOI
    1. Nie J., Chen X., Wang Z.L. Electrically responsive materials and devices directly driven by the high voltage of triboelectric nanogenerators. Adv. Funct. Mater. 2019;29:1806351. doi: 10.1002/adfm.201806351. - DOI
    1. Zhang J. Switchable and Responsive Surfaces and Materials for Biomedical Applications. Elsevier; Cambridge, UK: 2014. pp. 3–43.

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