Porphyrin-Based Fluorescent Probe for Nanomolar Detection of Cu2+ and Ni2+ Ions

Shin, So-Hyun; Kim, Jihyun; Moon, Hyungkyu; Sheshashena Reddy, T.; Choi, Myung-Seok

doi:10.3390/molecules31101739

This is an early access version, the complete PDF, HTML, and XML versions will be available soon.

Open AccessArticle

Porphyrin-Based Fluorescent Probe for Nanomolar Detection of Cu²⁺ and Ni²⁺ Ions

by

So-Hyun Shin

¹,

Jihyun Kim

²,

Hyungkyu Moon

¹,

T. Sheshashena Reddy

¹ and

Myung-Seok Choi

^2,*

¹

Department of Materials Science and Engineering, Konkuk University, 120 Neungdong–ro, Gwangjin–gu, Seoul 05029, Republic of Korea

²

Advanced Materials Program, Department of Materials Science and Engineering, Konkuk University, 120 Neungdong–ro, Gwangjin–gu, Seoul 05209, Republic of Korea

^*

Author to whom correspondence should be addressed.

Molecules 2026, 31(10), 1739; https://doi.org/10.3390/molecules31101739

Submission received: 6 April 2026 / Revised: 18 May 2026 / Accepted: 18 May 2026 / Published: 19 May 2026

(This article belongs to the Section Analytical Chemistry)

Download Versions Notes

Abstract

Copper is an indispensable trace element for maintaining metabolic homeostasis; however, the dysregulation and subsequent accumulation of Cu²⁺ are critically linked to neurodegenerative pathologies, including Alzheimer’s disease in humans. Consequently, the development of robust analytical tools for Cu²⁺ monitoring is of paramount importance. Here, we report a 2,2′-dipicolylamine porphyrin (DPAP)-based fluorescent sensor designed for the precise detection of metal cations. Photophysical investigations reveal that DPAP operates via a rapid turn-off fluorescence mechanism, achieving high-performance sensing in the parts-per-million range. Notably, the probe demonstrates exceptional sensitivity with detection limits of 26.3 nM for Cu²⁺ and 34.8 nM for Ni²⁺. Interference studies demonstrated the selectivity of DPAP for Cu²⁺ over a diverse range of competing metal ions such as Na⁺, Ag⁺, Ni²⁺, Cr³⁺, Pb²⁺, Al³⁺, Fe²⁺, Cd²⁺, and Zn²⁺. These results indicate that DPAP is a sensitive and selective probe suitable for copper ion detection.

Keywords: porphyrin sensor; fluorescence; 2,2′-dipicolylamine; metal cation; copper(II) ion

Share and Cite

MDPI and ACS Style

Shin, S.-H.; Kim, J.; Moon, H.; Sheshashena Reddy, T.; Choi, M.-S. Porphyrin-Based Fluorescent Probe for Nanomolar Detection of Cu²⁺ and Ni²⁺ Ions. Molecules 2026, 31, 1739. https://doi.org/10.3390/molecules31101739

AMA Style

Shin S-H, Kim J, Moon H, Sheshashena Reddy T, Choi M-S. Porphyrin-Based Fluorescent Probe for Nanomolar Detection of Cu²⁺ and Ni²⁺ Ions. Molecules. 2026; 31(10):1739. https://doi.org/10.3390/molecules31101739

Chicago/Turabian Style

Shin, So-Hyun, Jihyun Kim, Hyungkyu Moon, T. Sheshashena Reddy, and Myung-Seok Choi. 2026. "Porphyrin-Based Fluorescent Probe for Nanomolar Detection of Cu²⁺ and Ni²⁺ Ions" Molecules 31, no. 10: 1739. https://doi.org/10.3390/molecules31101739

APA Style

Shin, S.-H., Kim, J., Moon, H., Sheshashena Reddy, T., & Choi, M.-S. (2026). Porphyrin-Based Fluorescent Probe for Nanomolar Detection of Cu²⁺ and Ni²⁺ Ions. Molecules, 31(10), 1739. https://doi.org/10.3390/molecules31101739

Article Menu

Porphyrin-Based Fluorescent Probe for Nanomolar Detection of Cu²⁺ and Ni²⁺ Ions

Abstract

Share and Cite

Article Metrics

Article Access Statistics

Further Information

Guidelines

MDPI Initiatives

Follow MDPI