Molecular Optical Analyzers Based on Smartphones for High School and Universities

Abstract

Technically simple and extremely cheap setups for colorimetric and fluorimetric analyses using a smartphone camera are presented. Laboratory activities on digital colorimetric and fluorimetric analyses for students of secondary and higher educational institutions are proposed, namely, photocolorimetric determination of acetylsalicylic acid in Cardiomagnyl and copper and nickel in nickel−silver alloy, and fluorimetric determination of riboflavin mononucleotide in its injection solution. Nickel and copper in nickel−silver are determined simultaneously; i.e., two-component colorimetric analysis is performed, which allows the introduction of linear regression analysis to students. The use of the developed setups and activities can help to form the students' skills of a meaningful choice of the conditions for measuring the analytical signal to achieve the required metrological characteristics of the determination results.

Iron Quantification in Dietary Supplements using Four Colorimetric Assays

“…In the pH range 0.7–2.5, the salicylic acid assay has been used to quantify salicylic acid in liquid facewash , and acetylsalicylic acid hydrolyzed samples. , …”

“…In the pH range 0.7−2.5, the salicylic acid assay has been used to quantify salicylic acid in liquid facewash 82,83 and acetylsalicylic acid hydrolyzed samples. 84,85 Here, the salicylic assay was carried at a pH close to 5, where Fe 3+ and salicylate form a red complex like in the KSCN assay, and its λ max value was also close to that of the FeSCN 2+ complex. The value of 480 nm corresponds to the B channel, and the G channel gave the highest calibration sensitivity (Figure 6).…”

Whey Protein Analysis Using the Lowry Assay and 96-Well-Plate Digital Images Acquired Using Smartphones

“…Normally, colorimetric assays were carried out using spectrophotometers. However, nowadays, digital images obtained using electronic devices such as smartphones and scanners have been widely used instead of spectrophotometers. − For example, Na + , F – , Fe 3+ , − Cu 2+ , , NO 2 – , NO 3 – , tyrosinase, glucose, proteins, ,, food dyes, − reducing compounds, and pharmaceuticals − were quantified using digital images.…”

Taking School Instrumentation One Step Forward: A Do-It-Yourself Type Spectrophotometer and a Jupyter Notebook That Enable Real Time Spectroscopy during School Lessons

“…The introduction of spectroscopy in schools worldwide faces a significant challenge: the commercially available analytical instruments are relatively expensive. Moreover, even when available, their educational impact is up to a point questionable, since there is always the problem of students viewing them as black boxes. − In order to diminish instrument cost and properly discuss instrumentation in the classroom, the construction of several do-it-yourself (DIY)-type devices has been reported in the past decade, e.g., spectrophotometers, ,− single wavelength spectrophotometers, − fluorometers, ,,,,,,− atomic emission spectrophotometers, polarimeters, nephelometers, and Raman spectrometers, , many of which contain “smart” phones as optical detectors. − Despite the fact that most of them are well built, their main drawback, when the discussion comes to full wavelength scanning, is that they require time-consuming postprocessing of the acquired spectral images, e.g., with ImageJ, Spectral Workbench, or other relative software.…”