A recent article in Scientific Reports , explored the synthesis of gold nanoparticles (AuNPs) and their integration into three-dimensional (3D) printed optical fiber probes (OFPs). By combining 3D printing and nanotechnology, researchers enhanced the optical properties of the fiber probes, highlighting their potential applications in sensing and biomedical applications.
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Advances in Fiber Optic Technology
Optical fiber has transformed communications and sensing technology by enabling the efficient and precise transmission of light, making it essential in communications, medical diagnostics, and environmental monitoring.
Incorporating nanomaterials such as AuNPs into optical fibers can improve their performance through unique optical phenomena such as surface plasmon resonance (SPR). SPR occurs when light interacts with metal nanoparticles, resulting in increased light absorption and scattering. By tuning the size, shape, and concentration of AuNPs, the light sensitivity and functionality of these devices can be optimized to support biosensing, imaging, and photonics applications.
Synthesis and integration methods
The authors used a depolymerization method to synthesize AuNPs and integrate them into 3D-printed optical fiber probes (OFPs).The resin formulation consisted of polyethylene glycol diacrylate (PEGDA) and hydroxyethyl methacrylate (HEMA) with trimethoxybenzoylphosphine oxide (TPO) as a photoinitiator to enable UV-induced polymerization.
The printed OFPs were immersed in a boiling solution of gold(III) chloride hydrate, which served as the precursor of AuNPs, and heating promoted the reduction of gold ions, leading to the in situ formationof AuNPs within the polymer matrix
The fabrication process was performed using a digital light processing (DLP) printer with a resolution of 3840 × 2400 pixels, allowing for high-precision printing. Parameters such as layer thickness (25 μm) and exposure time (35 s per layer) were carefully controlled to optimize the synthesis of nanoparticles.
The effect of different gold precursor concentrations and immersion times on the nanoparticle formation and optical performance was evaluated. Characterization techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) were used to analyze the nanoparticles and their integration into the polymer matrix.
Optical properties and performance
This study demonstrated that the integration of AuNPs significantly improved the optical performance of 3D printed OFPs. TEM confirmed that the AuNPs were spherical with an average size of approximately 30 nm. FTIR spectra showed characteristic peaks corresponding to carbon-oxygen (C-O) and C=C bonds, further confirming the successful cross-linking of the polymer components.
Optical characterization showed that the reflection and transmission spectra of the OFP were strongly influenced by both the AuNP concentration and immersion time. A significant decrease in the reflection spectrum was observed between 500 and 600 nm, corresponding to the localized surface plasmon resonance (LSPR) of AuNPs. This behavior demonstrated the enhanced light absorption and scattering, highlighting the suitability of this fiber for optical sensing applications.
Furthermore, the fiber maintains stable performance under various temperature and pH conditions, demonstrating its suitability for practical applications. These results highlight the potential of the fiber for use in optical devices requiring selective wavelength filtering and enhanced sensing capabilities.
Applications of optical fibers embedded with gold nanoparticles
The integration of AuNPs into 3D printed optical fibers offers promising opportunities in many fields. Their improved optical properties make them suitable for advanced sensing techniques that require high sensitivity to environmental changes. In biomedical applications, these fibers can be used to detect biomarkers and improve the accuracy of diagnostics.
The versatility of 3D printing enables rapid prototyping and cost-effective production of custom optical components to support R&D efforts. Additionally, controlled synthesis of nanoparticles allows precise tuning of optical properties, potentially leading to improved communications, including improved signal processing and transmission.
The tunable optical properties of these fibers also make them suitable for devices such as optical filters and modulators, which are essential in advanced communication systems and environmental monitoring.
Future Directions
The authors demonstrated that AuNPs can be synthesized in situ within 3D printed OFPs , highlighting the potential of combining nanotechnology with additive manufacturing. The ability to achieve tunable optical properties through the controlled synthesis of AuNPs represents an important step towards the development of multifunctional optical devices. Future work may focus on improving the synthesis process and exploring alternative nanoparticles to further extend the functionality of 3D printed optical devices.
Reference magazines
Chekkaramkodi, D., et al . (2024). In situ synthesis of gold nanoparticles and their integration into 3D printed fiber optic probes. Scientific Reports . DOI: 10.1038/s41598-024-81139-x, https://www.nature.com/articles/s41598-024-81139-x
