Diamond Particles Incorporated Fiber-Optic Probes for Biosensing Purposes

Integration of nanodiamonds with glass fibers is a powerful method of scaling diamond biosensing functionality. In this overview, we report on the volume incorporation approach for the integration of nanodiamond particles with optical fibers and coating with diamond particles to tailor optical sensing properties. The 750 nm and 140 nm diameter diamond particles were applied in those procedures. Manufactured optical fiber probes were analyzed using Raman mapping, SEM, optical and fluorescence spectra. SEM analysis reveals distinctly that the majority of the glass area is covered with single, separated diamond particles. Nanodiamond-doped fiber cross-section revealing a homogenous glass structure with incorporated sectionally nanodiamond particles. Diamond particles are tightly included in the glass structure with a mean adjacent distance of approx. 2.5 µm. Core-incorporated diamond particles allow to guide its fluorescence along the fiber is sensitive to the external environment. Diamonds deposited on the surface of optical-fiber probes tailor their transmittance and provide the interface for biosensing enhancing both optical and electrochemical responses. Following dedicated experimental work, doped diamond particles have the potential of extending the existing models with practical ways of optimizing signal coupling and readout to the guided modes in optical fiber-based biosensing probes.