Comment on: “Dissolved oxygen sensing characteristics of plastic optical fiber coated with hydrogel film” – The wider context of fibre optic oxygen sensing
A recently published article by Bian et al. (2021) presents a novel plastic optical fibre coated with hydrogel film to measure dissolved oxygen via luminescence quenching. The article concludes that “The sensor with biocompatible material is expected to be applied to the monitor of dissolved oxygen in the domain of biomedicine”. However, the oxygen sensor presented contains ruthenium, a toxic material that is considered unsafe for clinical applications. It is unclear whether the hydrogel film coating may be sufficient to prevent direct contact between ruthenium and human tissue in clinical applications. However, platinum porphyrin has been used in fibre optic oxygen sensors in pre-clinical applications. This Comment article provides a brief overview of some platinum porphyrin-based fibre optic oxygen sensors that, despite an advanced degree of maturity and biocompatibility, were overlooked in the recently published article.