Molecular modeling of B24O24 scaffolds for the electrochemical sensing and detection of nitrosourea and hydroxyurea drugs: Insight from DFT calculations

Abstract

Hydroxyurea (HU) and nitrosourea (NU) are well-known chemotherapeutic medications. Still, their efficiency is limited due to the possibility of their misuse and the emission of small quantities of unmetabolized drugs into the environment. Many side effects might occur from taking these drugs. Nanomaterials for drug detection are crucial in pharmaceutical research, especially in cancer therapy applications like HU and NU. This work aimed to examine the sensitivity of [Formula: see text] nanocage for detecting HU and NU drugs by using density functional theory (DFT). We studied the interactions between HU/NU drugs and the [Formula: see text] nanocage using optimized geometries, adsorption energies, FMO, NCI, NBO and QTAIM analyses by employing DFT and TD-DFT at the B3LYP-D3/6-31G(d,p) level of theory. Specifically, the adsorption energy estimates of [Formula: see text]32.06[Formula: see text]kcal/mol for the NU@[Formula: see text]-1∗ complex and [Formula: see text]28.79[Formula: see text]kcal/mol for the HU@[Formula: see text]-5 complex show that the HU/NU drugs are firmly adsorbed onto [Formula: see text] and that the process is exothermic. Through NCI and QTAIM analyses, noncovalent interactions, mainly the van der Waals forces, have been observed between [Formula: see text] and the HU/NU drugs. When HU/NU interacts with the surface of [Formula: see text], new energy levels are formed in the [Formula: see text] PDOS. After analyzing the [Formula: see text] value, sensitivity and recovery time as indicators of the [Formula: see text] nanocage sensing capability, it was found that the NU@[Formula: see text]-2∗ complex exhibited the best conductivity ([Formula: see text]S/m), fine sensitivity ([Formula: see text]) and most minor stability due to its small energy gap value of 3.47[Formula: see text]eV. However, the most stable complex is HU@[Formula: see text]-3, which has an energy gap of 5.08[Formula: see text]eV. At a value of [Formula: see text]s, the complex NU@[Formula: see text]-4∗ has the quickest recovery time. As a result of its rapid recovery time, the [Formula: see text] nanocage is highly desirable for its potential application as an HU/NU drug sensor. This proves that HU/NU drugs can be effectively detected by the [Formula: see text] nanocage. Our results suggest that the [Formula: see text] nanocage has the potential to improve drug detection (HU/NU), suggesting potential avenues for further progress.