Photoelectrochemical Biosensors: Recent Progress and Critical Challenges

Dear Colleagues,

The past decade has witnessed transformative progress in photoelectrochemical biosensors, delivering unprecedented insights into disease signatures, biological heterogeneity, and molecular interactions. This emerging capability to probe and accurately quantify a vast array of biomarkers—including nucleic acids, proteins, and molecular complexes—even at the single-molecule level, is reshaping biomedical diagnostics, precision medicine, and analytical chemistry.

Innovations in ratiometric biosensors, multiplexed detection, and multi-omic profiling techniques now enable simultaneous, ultra-sensitive analysis of microRNAs, mutant DNAs, and proteins from minimal clinical samples, overcoming traditional detection limits and reducing cross-reactivity. Recent advancements, such as photocurrent polarity-switchable imaging of single living cells by light-addressable electrochemical sensor,  portable photoelectrochemical platforms, ratiometric/multiplexed photoelectrochemical platforms, and machine learning in smart photoelectrochemical biosensor, have set the stage for robust panels of molecular diagnostics with application to early disease detection, therapy monitoring, and fundamental biomolecular research.

Nevertheless, challenges remain—from substrate engineering and signal amplification to surface passivation, probe design, data analysis, and clinical translation. As the field evolves, there is an urgent need for innovative detection strategies, high-throughput platforms, and new tools to understand molecular complexity in living systems.

This Special Issue welcomes original research articles and in-depth reviews addressing all aspects of photoelectrochemical biosensors and their translation to various applications. Topics of interest include, but are not limited to:

• Digital counting or imaging of single nucleic acids, proteins, and other biomolecules;
• Emerging strategies for multi-omic profiling and integration on unified biosensing platforms;
• Advances in self-powered/ratiometric/multiplexed analysis of electrochemical or photoelectrochemical detection techniques;
• Surface passivation, probe engineering, and minimizing assay interference;
• Ultra-sensitive detection and quantitation without amplification;
• Bioamplification based on a DNA nanomachine;
• Portable photoelectrochemical biosensor innovation
• Bioinformatics and machine learning for single-molecule data analysis;
• Clinical applications: cancer, infectious disease, neurological and cardiovascular diseases;
• Contributions to antibody development, protein purification, and affinity reagent engineering for biosensors.

We encourage submissions reporting technical advances, significant applications, and theoretical or computational studies relevant to current and future challenges in photoelectrochemical biosensing.

Prof. Dr. Jing Li
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 250 words) can be sent to the Editorial Office for assessment.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Biosensors is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2200 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.