Use of different matrices to construct the standard curve for the paracetamol dosage by visible spectrophotometry

Caroline M Barros,Yoko Oshima-Franco,Andresa P Silva,Juliana O S S Mizael

doi:10.5935/1676-2444.20210026

Caroline M Barros, Yoko Oshima-Franco + Show 2 more

Open Access

https://doi.org/10.5935/1676-2444.20210026

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Abstract

ABSTRACT Introduction: Acute paracetamol poisoning is confirmed by the determination of its serum level and allows assessing the risk of hepatotoxicity, which can be monitored by the Rumack-Matthew nomogram for the administration of the N-Acetylcysteine antidote, as well as for the prognosis of intoxication. Objective: Because of its analytical importance, we evaluated the influence of different matrices (ultrapure water, serum, and plasma) on the construction of the paracetamol calibration curve, aiming to reduce the analytical cost and facilitate its implementation in clinical and emergency laboratories. Material and methods: A standard stock solution of paracetamol of 1 mg ml-1 was obtained, from which appropriate dilutions originated the following concentrations 20, 50, 100, 150, 200, 250, and 300 mg l-1 in the different matrices, in triplicate, reading at complete after 430 nm in spectrophotometer and reproduced after three months. The results were statistically analyzed (p < 0.05). Results and discussion: Good laboratory practices include remaking the calibration curve when stock reagents are remade aiming to readjust the line equation indicated by a measuring instrument. The biological samples indicated as matrices on a calibration curve are usually serum and plasma. However, these biological products, when commercially purchased, are of high cost. Ultrapure water can replace serum and plasma in the paracetamol calibration curve according to the linearity of the curve, which showed the same trend line for the three matrices. Conclusion: The three matrices can be used in the construction of the paracetamol calibration curve, but the use of ultrapure water reduces the analysis costs.

Highlights

The history of muscle biopsy dates back to 1860, when Duchenne first performed a biopsy on a patient with symptoms of myopathy[1]
The twenty-first century has brought in a new spectacular progress in the utility of muscle biopsy with the commencement of molecular methods
The molecular era was made possible by the development of molecular biology and its application to muscle diseases

Summary

Introduction

The history of muscle biopsy dates back to 1860, when Duchenne first performed a biopsy on a patient with symptoms of myopathy[1]. The introduction of enzyme histochemical methods by Victor Dubowitz, in 1970, revolutionized the role of muscle biopsy in the diagnosis of various primary and secondary muscle diseases[2]. The adaptation of histo- and cytochemical techniques to the study of muscle biopsies improved diagnostic accuracy and enabled the identification of new changes and structures[3, 4].

Results

Conclusion