ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Detection of trace L-aspartic acid using simple and cost-effective biosensors: experimental study along with density functional theory (DFT) and finite difference time domain (FDTD) numerical investigations

Hossein Sahbafar, Atefe Mohsennezhad, Leila Zeinalizad, Hadis Jamshidvand, Saeideh Mehmandoust, and Vahid Eskandari

School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran

E-mail: hosseinsahba@gmail.com

Received: 25 October 2024  Accepted: 13 November 2025

Abstract:

A deficiency of L-aspartic acid (L-asp) can cause some problems, including depression, fatigue, low mood, and injury to the nervous system. L-asp improves the parameters of seminal fluid and is effective in the treatment of male infertility. Despite the known significance of L-asp in health, existing detection methods are often complex and costly, limiting their practical applications. Previous relevant studies have not adequately addressed L-asp detection, highlighting a gap in accessible and effective biosensors. This work focused on detecting L-asp using sensitive, cheap, and straightforwardly developed surface-enhanced Raman scattering (SERS) sensors. After the fabrication of AgNPs by a chemical reduction method and characterization of them, a linear range of 10⁻¹ to 10⁻⁹ M of L-asp was analyzed using Raman spectroscopy, and the density functional theory (DFT) method was employed to confirm the outcomes. The limit of detection (LOD) of the developed substrates for identifying L-asp was 10^− 9 M. Moreover, enhancement factors (EFs) were calculated to be 1.410 × 10⁸ and 2.224 × 10⁸ using experimental results and finite-difference time-domain (FDTD) simulation, respectively. These straightforward, inexpensive, and thoroughly developed substrates can serve as sensitive biosensors for various applications.

Keywords: L-aspartic acid (L-asp); Surface-enhanced Raman scattering (SERS); Glass substrates; Nervous system; Infertility

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04514-6

Chemical Papers 80 (3) 2245–2259 (2026)