Surface-enhanced Raman spectroscopy of zirconia-based implants

Abstract

This work employs stabilized gold nanostars as substrate for surface enhanced Raman spectroscopy (SERS) to detect extremely little amountof monoclinic phase zirconia in bone implant prototypes. The nanostars used have localized surface plasmon resonance at 690 nm. Spectral maps, on clean and on nanostars covered surface, were obtained exactly at the same position using confocal Raman spectroscopy. Comparison of the two maps shows that there are more monoclinic phases detected in the nanostars-covered surface possibly due to the lightning rod effect in the nanostar tips. While SERS is a well-established detection technique and extensively being used for the detection of trace amounts and even single-molecule of chemical species, it has not been widely applied to detection in solids. Very little work has been done to exhibit SERS in solid materials and it remains a challenge to achieve SERS enhancement on dense and polished solids, such as zirconia implants. We report an unprecedented attempt on SERS on solid zirconia, which provides early evidence of the effectivity of the technique even on non-porous materials. With further improvement in sensitivity, SERS is a promising technique for the early detection of monoclinic phase in zirconia-based implants.