Research Article Quantification of DNA through the NanoDrop Spectrophotometer: Methodological Validation Using Standard Reference Material and Sprague Dawley Rat and Human DNA Alejandro Monserrat Garc´ ıa-Alegr´ ıa , 1 Iv´ an Anduro-Corona, 2 CinthiaJhovannaP´ erez-Mart´ ınez , 1 Mar´ ıa Alba Guadalupe Corella-Madueño, 1 Mar´ ıaLucilaRasc´ on-Dur´ an, 1 and Humberto Astiazaran-Garcia 1,2 1 Universidad de Sonora, Departamento de Ciencias Qu´ ımico Biol´ ogicas, Hermosillo, Sonora CP 83000, Mexico 2 Centro de Investigaci´ on en Alimentaci´ on y Desarrollo, A.C. (CIAD AC), Coordinaci´ on de Nutrici´ on, Hermosillo, Sonora CP 83304, Mexico Correspondence should be addressed to Humberto Astiazaran-Garcia; hastiazaran@ciad.mx Received 5 July 2020; Revised 3 November 2020; Accepted 16 November 2020; Published 29 November 2020 Academic Editor: Mohamed Abdel-Rehim Copyright © 2020 Alejandro Monserrat Garc´ ıa-Alegr´ ıa et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. is study aimed to validate an analytical method to determine DNA concentration using standard reference material (NIST SRM 2372) and Sprague Dawley rat and human DNA. Microvolumes were used to analyse DNA samples. Linearity showed correlation coefficients higher than R ≥ 0.9950, and the precision value was ≤2% CV. Trueness based on bias and the percentage of recovery showed bias values lower than Z-test with a 95% confidence level and a recovery percentage within the range (% Rec � 100% ± 5%), and the stability of the samples was 60 days (2–4 ° C). 1.Introduction Diagnostic service laboratories have been experiencing an increasing demand of molecular analysis; therefore, the implementation of good laboratory practices and quality assurance has become necessary. According to the Eur- achem Guide, “e laboratory should use the test and cal- ibration methods, including sampling, that satisfy the clients’ necessities and that are appropriate for the assays being performed...” [1]. DNA analysis and quantification have become a common process in these laboratories daily as a starting point of the different procedures being performed in the molecular biology laboratory. One of the most commonly used methods to estimate nucleic acid concentration is the measurement of sample absorbance at 260 nm [2]. e 260/280, 260/230, and 260/325 absorbance ratios are used to determine DNA purity and the presence of contaminants in the biological samples during the DNA extraction process [3, 4]. Currently, the most useful way to estimate DNA concentration and purity is through ab- sorbance measures of samples’ microvolumes using the NanoDrop spectrophotometer. Since its appearance [5], this normalised method has been used worldwide. Nevertheless, to the best of our knowledge, this methodology has not been integrally validated and the uncertainty of its measures has also not been determined, as recommended by international norms [1, 6]. at is, there are analytical parameters that must be determined to validate a measurement method. Among them are linearity, the limit of detection and quantification, precision under repeatability and reproducibility conditions, truthfulness through bias, and the recovery percentage and stability, among others. Recently, several researchers world- wide have committed to the validation of analytical meth- odologies to evaluate the DNA extraction process from microorganisms [7], to quantify DNA fragment amplification [8], for real-time PCR applications [9–13], for DNA extrac- tion from glial cells [14], to evaluate DNA methylation in the human genome by microarrays [15], to validate sequencing Hindawi International Journal of Analytical Chemistry Volume 2020, Article ID 8896738, 9 pages https://doi.org/10.1155/2020/8896738