New Nanodiamond Sensor for Paracetamol Detection

By Dr. Noopur JainReviewed by Susha Cheriyedath, M.Sc.Nov 25 2024

A recent study published in Chemosensors has introduced an innovative nanodiamond-based electrochemical sensor for detecting paracetamol (PAR) in pharmaceutical formulations. This novel approach enhances sensor performance, offering a sensitive, selective, and reliable method for pharmaceutical quality control.

Paracetamol is a widely used analgesic and antipyretic medication, and its accurate quantification is crucial for ensuring safety and efficacy in therapeutic applications. This study utilized nanodiamond (ND) materials to enhance the performance of electrochemical sensors, thereby providing an efficient and reliable method for paracetamol detection.

Background

Paracetamol is one of the most commonly used medications for pain relief and fever reduction, making its accurate quantification essential for ensuring safety and therapeutic efficacy. The study leverages the unique properties of ND, including high surface area, excellent electrochemical stability, and efficient electron transfer capabilities, to create an advanced sensor for paracetamol detection.

Nanomaterials, including nanodiamonds, have garnered significant attention in sensor technology due to their ability to enhance sensitivity and stability. This study highlights the limitations of traditional detection methods and demonstrates the potential of nanotechnology to overcome these challenges, particularly in pharmaceutical manufacturing where precise quality control is critical.

Sensor Development and Methodology

The development of the nanodiamond-based sensor involved careful and precise preparation to ensure it worked effectively. A key step was preparing the working electrode. The glassy carbon electrode (GCE) was polished to create a smooth, clean surface. Next, it was cleaned further by sonicating it in isopropyl alcohol for a minute, rinsing it with water, and then drying it completely.

The nanodiamond coating was prepared by suspending nanodiamonds in ultrapure water. This mixture was then stirred using ultrasonic waves to create a smooth and even dispersion. The prepared nanodiamond solution was carefully applied to the electrode surface and dried, forming a thin, uniform film.

To prepare the samples for testing, paracetamol tablets (either 500 mg or 750 mg) were crushed into a fine powder. A measured amount of this powder was mixed with a water and sodium hydroxide (NaOH) solution to dissolve the paracetamol completely. This solution was then sonicated, diluted with deionized water, and filtered to remove any remaining impurities. The filtered solution was further diluted to achieve the desired concentration for analysis.

The sensor’s performance was tested using two electrochemical techniques: cyclic voltammetry (CV) and differential pulse voltammetry (DPV). These methods helped assess how sensitive, selective, and stable the sensor was when detecting paracetamol. To ensure the results were accurate, they were compared to those obtained using a traditional spectrophotometric method outlined in the Brazilian Pharmacopoeia. This comparison confirmed that the nanodiamond-based sensor provided reliable and precise results.

Results and Discussion

The morphological and structural characteristics of the nanodiamonds used for GCE modification were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The SEM images revealed that the nanodiamonds were well-dispersed, forming spherical clusters with an average diameter of approximately 900 nm. The elemental analysis indicated a predominance of carbon, with negligible amounts of oxygen, confirming the successful preparation of the nanodiamond material.

The electrochemical performance of the ND/GCE was assessed through cyclic voltammetry, which demonstrated a significant enhancement in the peak current for paracetamol oxidation compared to the bare GCE. The sensor exhibited a linear response to paracetamol concentrations ranging from 0.1 to 100 μmol L⁻¹, with a detection limit calculated to be 0.03 μmol L⁻¹. The selectivity of the sensor was also evaluated in the presence of common excipients and potential interferents, showing minimal cross-reactivity and confirming the sensor's reliability for paracetamol detection in complex matrices.

The results were further corroborated by the spectrophotometric method, which provided comparable values for paracetamol concentrations in the tested pharmaceutical samples. This agreement between the two methods underscores the potential of the ND-based electrochemical sensor as a viable alternative for routine analysis in pharmaceutical quality control.

Conclusion

In conclusion, the study successfully demonstrates the development of a nanodiamond-based electrochemical sensor for the sensitive and selective detection of paracetamol in pharmaceutical formulations. The innovative use of nanodiamonds significantly enhances the electrochemical performance of the sensor, providing a reliable method for paracetamol quantification. The findings highlight the potential of nanotechnology in advancing sensor design and improving analytical methodologies in the pharmaceutical industry.

Future research may focus on optimizing the sensor's performance further and exploring its applicability to other pharmaceutical compounds, thereby broadening the scope of its use in quality control and safety assessments. The promising results of this study pave the way for the integration of nanomaterials in the development of next-generation sensors, ultimately contributing to enhanced public health outcomes through improved medication safety.

Journal Reference

de Oliveira Lopes D., Magalhães Marinho F., et al. (2024). A Nanodiamond-Based Electrochemical Sensor for the Determination of Paracetamol in Pharmaceutical Samples. Chemosensors 12, 243. DOI: 10.3390/chemosensors12110243, https://www.mdpi.com/2227-9040/12/11/243