A cost-effective microfluidic device for determination of biodiesel content in diesel blends

Author(s)

Soares, Samara ; Ramos-Lorente, Celia E. ; Ruiz-Garcia, Isidoro ; Rocha, Fabio R. P. ; Erenas, Miguel M. ; de Orbe-Paya, Ignacio ; Lopez-Ruiz, Nuria ; Capitan-Vallvey, Luis F.

• Document type: Journal article
• Source: SENSORS AND ACTUATORS B-CHEMICAL; v. 390, p. 7-pg., 2023-09-01.

Abstract

The increasing production and extensive use of biodiesel in the latest years call for the development of fast and cost-effective procedures for point-of-care analysis. One of the main quality parameters is the biodiesel content in diesel blends, which needs to conform to regional legislations. In this work, a microfluidic device exploiting chemical derivatization of alkyl esters and detection by smartphone-based digital-image colorimetry was developed. It was designed to ensure proper experimental conditions for chemical derivatization, including reagent release, and photometric measurements. Analytes reacted with alkaline hydroxylamine yielding the corresponding alkyl hydroxamates, measured as colored Fe(III) complexes. Analytical response was based on the measurement of the G (green) channel from RGB color system. By taking methyl linoleate as a model compound, a linear response was obtained from 0.1% to 0.6%(v/v) (Analytical signal = 69.6 +2.1 C, r = 0.999), coefficient of variation (n = 10) of 4.0% and limit of detection (99.7% confidence) of 0.04%(v/v). Procedure consumes 1.2 & mu;L of sample, 230 & mu;g of hydroxylamine, 480 & mu;g of NaOH, 14 & mu;g of Fe(III) and equivalent to 1.2 & mu;L of 69%(v/v) HNO3. Accurate results were achieved in relation to the MIR reference method, with agreement at the 95% confidence level. (AU)

• FAPESP's process: 21/12242-5 - Development of a cost-effective microfluidic device to determine biodiesel content in diesel blend
• Grantee: Samara Soares
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 18/07687-5 - Exploitation of novel calibration strategies, digital images and flow analysis for biodiesel quality control
• Grantee: Samara Soares
• Support Opportunities: Scholarships in Brazil - Doctorate