Optimization of Polydimethylsiloxane-Modified Composite Synthesis and Its Impact on Collagen Interactions: Perspectives for Biomedical Applications

Abstract

This research explores how silica composites modified with polydimethylsiloxane interact with collagen, aiming to enhance their application in the biomedical field. By adjusting the amount of polydimethylsiloxane in these composites, we evaluated their capacity to bind with collagen, an essential feature for biomaterials used in tissue engineering and drug delivery. Our findings reveal that incorporating polydimethylsiloxane into silica composites significantly boosts collagen attachment, indicating strong binding interactions. Notably, the collagen adhered to the composites maintains its natural structure, ensuring its functionality and compatibility with living tissues. This aspect is critical for biomaterials that support cell growth and regeneration in tissue scaffolds. Additionally, this study investigates how the viscosity of polydimethylsiloxane influences collagen binding, offering insights into the tailoring of composite properties for better biological performance. This work highlights the potential of polydimethylsiloxane-modified silica composites in creating innovative biomaterials for regenerative medicine and targeted therapeutic delivery.

Keywords: collagen; polydimethylsiloxane; silica composite; synthesis optimization.

Figure 1

Conceptual scheme of the research methodology.

Figure 2

Effect of PDMS content (A), buffer pH (B), and H₂O:TMOS molar ratio (C) on the sol gelation time (blue dashed line—95% confidence interval; red dotted cross—values of tested variables fixed).

Figure 3

FTIR spectra of PDMS-modified silica composites. All the spectra are normalized by the absorption band of the Si-O vibration at about 1000 cm⁻¹.

Figure 4

(A) Results of the determination of the concentration of native collagen in the solution above the composite during incubation for 0, 5, 10, 15, and 20 days (d = days); (B) results of the determination of the concentration of total collagen in the solution above the composite during incubation (X + CI—collagen and PDMS-modified silica composite incubation mixture; CI—control collagen solution; and X—control composite in the buffer).

Figure 5

The result of the microscopic observation of a PDMS-modified silica composite incubated with fluorescently labeled collagen (top row; (A): using a light microscope, (B): using a fluorescence microscope) and an unmodified silica composite incubated with fluorescently labeled collagen (bottom row; (C): using a light microscope, (D): using a fluorescence microscope).

Figure 6

(A) Influence of PDMS content (wt%) in the silica composite on the rate of collagen adsorption from a solution; and (B) correlation between the viscosity (cSt) of the employed PDMS and the composite’s capacity for collagen adsorption.

Figure 7

Platelet adhesion confirmed by LDH assay to the following: SiO₂—pure silica composites; SiO₂-PDMS—composites modified with PDMS without further incubation with type I collagen; SiO₂-PDMS-CI—composites modified with PDMS and incubated with native type I collagen; andSiO₂-PDMS-CI fibr.—composites modified with PDMS, incubated with native type I collagen, and placed in fibril forming conditions.