Seleno-BODIPY as a fluorescent sensor for differential and highly selective detection of Cysteine and Glutathione for bioimaging in HeLa cells

Author(s)

Cugnasca, Beatriz S. ; Junior, Tharcisio C. T. ; Penna, Tatiana C. ; Zuluaga, Norma L. B. ; Bustos, Silvina O. ; Chammas, Roger ; Cuccovia, Iolanda M. ; Correra, Thiago C. ; Dos Santos, Alcindo A.

• Document type: Journal article
• Source: DYES AND PIGMENTS; v. 236, p. 12-pg., 2025-01-21.

Abstract

Biothiols like cysteine and glutathione are involved in maintaining redox balance in living organisms and perform essential functions in pathological and physiological processes. Depending on the concentration they can be regarded as biomarkers for oxidative stress and be associated with diseases such as cancer, immune dysfunctions, among others. Herein, we report a synthetic route for a Seleno-BODIPY to act as a fluorescent probe by reaction with biological thiols in living cells. The probe presented high selectivity for biothiols between 26 analytes of biological interest. Distinct responses for Cys and GSH by colorimetric and fluorometric analysis in a turn-on fluorescent process were observed, with low detection limits (61.18 nM for Cys; 1.66 mu M for GSH), ratiometric response by absorption for Cys, high fluorescence quantum yield after reaction (88.1 % for Cys and 31.8 % for GSH), high sensitivity, and fast response time for Cys. A mechanistic investigation was conducted, using N-ethylmaleimide as a thiol trapper. This strategy allowed us to conclude that the reaction between BODIPY and Cys gave an amino-BODIPY while the analogous reaction with GSH results in a thio-BODIPY with different spectral shifts, making possible the distinction and quantification of both analytes by fluorescence. Kinetic studies demonstrated that the reaction with Cys is much faster than with GSH, allowing them to be differentiated. A pH study showed that the probe behaves well at a physiological pH range (6.2-8.0). Finally, the Se-BODIPY was successfully used to detect biothiols in HeLa cells, demonstrating the sensor applicability in real systems, presenting high potential for both diagnostics and analytical (bio)chemistry areas. (AU)

• FAPESP's process: 14/50983-3 - INCT 2014: complex fluids
• Grantee: Antonio Martins Figueiredo Neto
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 21/06726-0 - Investigation of reactive intermediates in complex chemical and biochemical processes
• Grantee: Thiago Carita Correra
• Support Opportunities: Research Grants - Young Investigators Grants - Phase 2
• FAPESP's process: 17/20262-0 - Unraveling electrochemical reaction intermediates by mass spectrometry coupled to ion vibrational spectroscopy
• Grantee: Tatiana Casselli Penna
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 23/01092-8 - Polymeric particles containing seleno-BODIPYs for applications as fluorescent sensors in biological systems
• Grantee: Beatriz dos Santos Cugnasca
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• FAPESP's process: 15/08539-1 - Multi-User Equipment approved in grant 2014/15962-5: ion trap mass spectrometer modified to perform infrared vibrational spectroscopy (IRMPD)
• Grantee: Thiago Carita Correra
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 22/10797-2 - Development of Advanced Methods for the evaluation of chemical and biochemicals system's isomers using mass spectrometry
• Grantee: Tatiana Casselli Penna
• Support Opportunities: Scholarships in Brazil - Technical Training Program - Technical Training
• FAPESP's process: 19/07634-1 - Synthesis of hydrosoluble seleno- and telluro-BODIPY as fluorescent sensors for biological applications
• Grantee: Beatriz dos Santos Cugnasca
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 22/00498-8 - Multi-user equipment approved in grant 21/06726-0: ion mobility mass spectrometry system (IMS-MS)
• Grantee: Thiago Carita Correra
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 18/24434-3 - Synthesis and Applications of Seleno- and Telluro-BODIPY Derivatives: Near Infrared Fluorescent Sensors
• Grantee: Alcindo Aparecido dos Santos
• Support Opportunities: Regular Research Grants