Detection of the p53 Gene Mutation Using an Ultra-sensitive and Highly Selective Electrochemical DNA Biosensor

• Published in: Journal of the Mexican Chemical Society 2023-01, Vol.67 (1), p.33-45
• Main Authors: Garcia-Melo, Luis Fernando, Chagoya Pio, Norma Andrea, Morales-Rodríguez, Miguel, Madrigal-Bujaidar, Eduardo, Madrigal-Santillán, Eduardo O., Álvarez-González, Isela, Pineda Cruces, Rosa N., Batina, Nikola
• Format: Article
• Language: English
• Subjects: Chemistry, Multidisciplinary
• ISSN: 1870-249X; 2594-0317
• DOI: 10.29356/jmcs.v67i1.1880

The p53 gene— “the guardian of the genome”—is responsible for maintaining the integrity of the genome, along with cell cycle regulation, apoptosis, and cell differentiation. New analytical devices are needed to recognize the main alterations this gene could suffer, since it is one of the most frequent in human cancer. For this reason, we developed an electrochemical DNA biosensor with high sensitivity and specificity to monitor the 175p2 mutation of the p53 gene. We modified a screen-printed gold electrode (SPGE) by immobilizing a thiolated DNA probe sequence with 11-mercaptoundecanoic acid to detect its complementary sequence through the hybridization reaction. Doxorubicin (Dox) was used to increase the sensitivity of the biosensor, and the entire process was evaluated using the Cyclic Voltammetry (CV) technique. The measurement range of the developed device is from 1 fM to 100 nM of the p53 gene mutation with a limit of detection (LOD) of 2.2 fM. In the presence of Dox, the LOD increased up to 175 aM, becoming one of the highest efficiency devices in the field. The electrochemical DNA biosensor selectively detects the p53 suppressor gene mutation; it distinguishes between different non-complementary and complementary sequences. Our results indicate a high potential of our sensor for the p53 gene 175p2 mutation detection, which is convenient in the early diagnosis of diseases related to this gene.   Resumen. El gen p53—“guardián del genoma”—es responsable de mantener la integridad del genoma, así como de la regulación del ciclo celular, la apoptosis, y la diferenciación celular. Es necesario desarrollar nuevos dispositivos analíticos para reconocer las principales alteraciones que este gen podría sufrir, ya que es uno de los más frecuentes en el cáncer humano. En este sentido, se desarrolló un sensor electroquímico de ADN de alta sensibilidad y especificidad para identificar la mutación 175p2 del gen p53. Para ello, se formó una monocapa sobre un electrodo de oro que contenía secuencias sonda de ADN tiolado junto con ácido 11-mercaptoundecanoico, las cuales se emplearon para detectar la mutación del gen a través de la reacción de hibridación. Finalmente, se utilizó doxorrubicina (Dox) para aumentar la sensibilidad del biosensor; el proceso se evaluó mediante la técnica de Voltamperometría Cíclica (VC). El rango de medición del dispositivo desarrollado es de 1 fM a 100 nM de la mutación del gen p53 con un límite de detección (LOD) de 2.2 fM. En presencia d