Introduction

We are pleased to present a feature issue of Biomedical Optics Express containing papers based on studies presented at the Optical Molecular Probes, Imaging and Drug Delivery conference which is part of the Optica Biophotonics Congress: Optics in the Life Sciences in Vancouver, Canada in April 2023.

The conference showcased a broad range of cutting-edge, peer-reviewed research composed of invited and contributed oral presentations as well as poster sessions. Conference attendees presented studies featuring advances in imaging instrumentation, signal processing, optical contrast agent and sensor development, biodistribution and quantification measurement approaches, intrinsic optical biomarker discovery, multi-modal techniques, and theranostic approaches. Presentations also spanned from “bench to bedside”, featuring exploratory clinical studies in humans as well as basic biological studies in small animals.

This feature issue contains 5 papers exemplifying the range of subjects. Feng et. al. [1] describes a dual-fluorescence agent method for quantifying pharmacokinetics in blood and tissue samples. Ivich et. al. [2] describes an optical method for quantifying systemic blood sodium levels using a circulating fluorescence nanosensor platform. Xue et. al. [3] developed a silica coated theranostic nano-platform that allowed enhancement of the photothermal effect and photoacoustic imaging contrast in tumors. Nguyen et. al. [4] reviewed methods for molecular and cellular imaging of the eye. Finally, Troncoso et. al. [5] used optical spectroscopy methods and tissue optical properties to assess the aggressiveness of cells in culture and in mice in vivo.

We thank the Optica editorial board and staff for supporting this effort and thank the research community for their enthusiastic participation in the event. We encourage all members of the community to join us at the next Optica Biophotonics Congress event that will take place in April 21–24, 2025 at the Loews Coronado Bay Resort in Coronado, CA, USA.