# Quantum and thermodynamic evaluation of C24 fullerene-based nanosensors for detection of mydayis in biomedical and drug detection applications

## TL;DR

This paper explores how different fullerene-based nanosensors can detect Mydayis, a drug with psychotropic effects, using quantum and thermodynamic methods.

## Contribution

The study introduces novel C24 fullerene and doped derivatives as nanosensors for Mydayis detection, combining electrochemical, optical, and adsorption properties.

## Key findings

- Pristine C24 is effective as an electrochemical sensor with moderate adsorption and conductivity changes.
- BC23 and SiC23 show strong adsorption but long recovery times, making them suitable for irreversible capture.
- BC23 has the best colorimetric response with a significant shift in absorption wavelength.

## Abstract

From a public health and forensic perspective, the detection of Mydayis (a long-acting amphetamine-based drug) is crucial due to its psychotropic effects. In this work, Density Functional Theory (DFT), Time-Dependent DFT (TD-DFT), and Quantum Theory of Atoms in Molecules (QTAIM) were employed to evaluate pristine C24 fullerene and its doped derivatives (BC23 and SiC23) as nanosensors for Mydayis. Key electronic, thermodynamic, optical, and adsorption-based parameters were calculated, and the IR spectrum simulated using DFT showed strong agreement with experimental IR data reported in the literature, confirming the reliability of the computational approach. Among the investigated structures, pristine C24 was identified as the most effective disposable electrochemical sensor, exhibiting moderate adsorption energy (− 23.88 kcal.mol−1), a measurable conductivity increase (2.74 × 109 → 2.77 × 109 A.m−2), and significant enhancements in dipole moment (0.00 → 11.253 D) and polarizability (170.8 → 285.994 a.u.). In contrast, BC23 and SiC23 demonstrated exceptionally strong adsorption behavior (− 53.09 and − 54.00 kcal.mol−1, respectively) and extremely long recovery times (8.13 × 1026 and 3.80 × 1027 s), establishing them as excellent high-capacity absorbers for irreversible Mydayis capture. Additionally, BC23 exhibited the most pronounced colorimetric response, with a dramatic bathochromic shift from 432 to 655 nm upon Mydayis binding, confirming its role as the best disposable colorimetric sensor. These findings highlight the complementary roles of C24, BC23, and SiC23 in the electrochemical, optical, and adsorptive detection of Mydayis and provide a robust theoretical foundation for future experimental sensor development.

The online version contains supplementary material available at 10.1038/s41598-025-34744-3.