Multimodal Mesoporous Silica Nanocarriers for Dual Stimuli-Responsive Drug Release and Excellent Photothermal Ablation of Cancer Cells

Figures & data

Figure 1 (A) Nitrogen adsorption/desorption isotherms (1) and pore size distribution (2) by the Barrett–Joyner–Halenda (BJH) analysis of S, S3, and FS3. (B) X-Ray Diffraction (XRD) intensity measurements of F, FS3, and FS3P-A. (C) Magnetic hysteresis loops of F, FS3P, FS3P-G, and FS3P-A; photographs of (1) Fe₃O₄ NPs and (2) FS3P-A NPs before and after separation with an external magnetic field.

Figure 2 (A) FT-IR spectra of (1) S, (2) FS3, (3) FS3P, and (4) FS3P-G. (B) SEM image and inset TEM image of Fe₃O₄ (F) (1), SEM image of FS3 (2), SEM image of FS3P (3), SEM image and inset TEM image of FS3P-A (4); TEM images of S (5), and TEM images of FS3P (6).

Figure 3 (A) Temperature-variation curves of S, S3P-G/C, FS3P-G/C, S3P-A/C, and FS3P-A/C, solutions during the exposure to an 808 nm laser at a power density of 1.5 W/cm² for 10 minutes; (B) cisplatin release profiles from SP/C, FS3P-G/C, and FS3P-A/C in PBS at pH 7.4 and pH 5.5; (C) cumulative cisplatin release from FS3P-G/C and FS3P-A/C in PBS at pH 5.5 without and with NIR irradiation (808 nm laser, 1.5W/cm²) for 10 minutes; the dotted lines shown in (C) indicate the temperature change of in-vitro solution induced by the irradiation of NIR light for 10 minutes; (D) mechanism of stimuli pH/NIR responsive controlled release from FS3P-G/C (1) and FS3P-A/C (2).

Table 1 Summary of Drug Release Data for Each Type of Particles Under Different Conditions of Time vs pH and NIR Irradiation

Kind of Nanoparticle	Compositions	pH Effect			NIR Irradiation Effect (pH 5.5)
		pH	Release Efficiency (%)	Release Saturation Time (hours)	3 Times of NIR (on/off)	Release Efficiency (%)	Release Saturation Time (hours)
SP/C	Silica NPs, Polydopamine, Cisplatin	pH 5.5	73.62±0.96	80	–	–	–
		pH 7.4	71.30±1.34	80	–	–	–
FS3P-G/C	Fe3O4, Silica NPs, APTMS-FITC, Polydopamine, Graphene oxide, Cisplatin	pH 5.5	39.23±0.43	80	off	39.23±0.43	80
		pH 7.4	27.85±0.43	60	on	64.07±0.75	30
FS3P-A/C	Fe3O4, Silica NPs, APTMS-FITC, Polydopamine, Au NPs, Cisplatin	pH 5.5	34.02±1.66	80	off	34.02±1.66	80
		pH 7.4	26.66±0.91	60	on	77.46±0.76	30

Figure 4 Confocal microscopy imaging and flow cytometry analysis of HeLa cells after incubation with as-prepared samples: (A) SP/C, (B) FS3P-G/C, (C) FS3P-A/C, and (D) FS3P-G-E/C.

Figure 5 Thin-section TEM images of cell incubated with magnetic mesoporous silica nanoparticles. (A) Control cells without nanoparticles, (B) SP/C, (C) FS3P-G/C, (D) FS3P-A/C, and (E) FS3P-G-E/C. Arrows denote metal oxide particles or particulate matter.

Figure 6 (A) Cytotoxicity against HeLa, SH-SY5Y, and HEK293 cells lines induced by different nanoparticles S, S3, SP/C, FS3P-G/C, FS3P-A/C, and FS3P-G-E/C at their concentrations ranging from 0.625 to 10 µg/mL. (B) Cell viability of HeLa cells (the up panel) and their morphological observation (the down panel) incubated with or without FS3P-A/C (concentration 5 μg/mL) with or without 808 nm NIR laser irradiation at 1.5 W/cm² for 5, 10, and 15 minutes.

Scheme 1 Schematic illustration of core-shell FS3, double layer coating by PDA and Au coating (FS3P-A/C), Graphene oxide wrapping and EGFR antibody conjugating (FS3P-G-E/C); mechanism of stimuli pH/NIR responsive controlled release; and biomedical application through Au/Fe₃O₄/PDA photothermal therapy, the magnetically guided and EGFR antibody target.