Digital image-based titrations

Gaião, Edvaldo da Nóbrega; Martins, Valdomiro Lacerda; Lyra, Wellington da Silva; Almeida, Luciano F.; Silva, Edvan Cirino da; Araújo, Mário César Ugulino de

doi:10.1016/j.aca.2006.04.048

Cited by 100 publications

(42 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This procedure for processing the data could be automated using software that already has been developed for similar applications. 57 We also obtained indistinguishable results to these when we photographed or scanned a device, and transmitted the digital information to a computer through existing wireless communication systems.…”

Section: Quantitative Measurement Of Analytes In Artificial Urinementioning

confidence: 83%

Simple Telemedicine for Developing Regions: Camera Phones and Paper-Based Microfluidic Devices for Real-Time, Off-Site Diagnosis

et al. 2008

View full text Add to dashboard Cite

This article describes a prototype system for quantifying bioassays, and for exchanging the results of the assays digitally with physicians located off-site. The system uses paper-based microfluidic devices for running multiple assays simultaneously, camera phones or portable scanners for digitizing the intensity of color associated with each colorimetric assay, and established communications infrastructure for transferring the digital information from the assay site to an offsite laboratory for analysis by a trained medical professional; the diagnosis then can be returned directly to the healthcare provider in the field. The microfluidic devices were fabricated in paper using photolithography, and were functionalized with reagents for colorimetric assays. The results of the assays were quantified by comparing the intensities of the color developed in each assay with those of calibration curves. An example of this system quantified clinically relevant concentrations of glucose and protein in artificial urine. The combination of patterned paper, a portable method for obtaining digital images, and a method for exchanging results of the assays with off-site diagnosticians offers new opportunities for inexpensive monitoring of health, especially in situations that require physicians to travel to patients (e.g., in the developing world, in emergency management, and during field operations by the military) to obtain diagnostic information that might be obtained more effectively by less valuable personnel.

show abstract

Section: Quantitative Measurement Of Analytes In Artificial Urinementioning

confidence: 83%

Simple Telemedicine for Developing Regions: Camera Phones and Paper-Based Microfluidic Devices for Real-Time, Off-Site Diagnosis

et al. 2008

View full text Add to dashboard Cite

show abstract

“…Uma solução tampão amônia/cloreto de amônio 0,3 mol L -1 e pH 10 foi preparada dissolvendo 8,025 g de NH 4 Cl(Synth) em 450 mL de água, ajustando-se o pH com uma solução de hidróxido de sódio Águas minerais comerciais provenientes de oito fontes distintas foram adquiridas no mercado local de Brasília e analisadas sem nenhum pré-tratamento. Nos referidos estudos, foram utilizadas cinco amostras de cada fonte, as quais pertenciam a lotes diferentes.…”

Section: Reagentes E Soluçõesunclassified

“…1 Empregandose imagens obtidas por câmeras fotográficas, scanners, webcams ou telefones celulares, conhecidos como smartphones, é possível realizar determinações qualitativas e quantitativas com desempenho adequado, sem a necessidade de instrumentos como espectrofluorímetros ou espectrofotômetros. [2][3][4] De fato, a literatura relata que, utilizando informações simples das imagens, como os valores de cores usualmente baseadas no sistema RGB (do inglês Red, Blue e Green) consegue-se obter resultados analíticos similares àqueles adquiridos com instrumentação já bem estabelecida, caracterizando esta estratégia em uma alternativa de menor custo para a realização de determinadas medidas instrumentais.…”

Section: Introductionunclassified

Classification of Mineral Waters Based on Digital Images Acquired by Smartphones

Neto¹,

Fonseca²,

Braga³

2016

Química Nova

View full text Add to dashboard Cite

publicado na web em 25/05/2016 CLASSIFICATION OF MINERAL WATERS BASED ON DIGITAL IMAGES ACQUIRED BY SMARTPHONES. This work describes a new procedure for classification of mineral waters based on digital images acquired by smartphones. Commercial waters from eight mineral springs plus distilled water and tap water were combined with eriochrome T black or murexide and transferred to a cuvette, which was positioned into a light controlled chamber. RGB (Red, Blue and Green) measurements of cuvette images were acquired in real time, using a free smartphone app, and employed as variables for the exploratory analysis. 2D data dispersion along component B for murexide (x axis) and component R for eriochrome T black (y axis) provides the clear visualization of clusters using the raw variables. Hierarchical cluster analysis (HCA) applied to this data confirmed the efficient discrimination of samples providing the characterization of nine clusters for the ten classes of water investigated. The classification of samples based on a k-nearest neighbors (k-NN) modelled to the efficiency rate of 100% for 8 classes and of 94.4% and 50% for the remaining classes, respectively, indicating the adequate performance of the proposed strategy. Considering the facilities to acquire the data, such as low cost instrumentation and reagents, and the rapidity of the procedures, this alternative may be applied for verification of commercial water adulteration.Keywords: smartphone; mineral waters; colorimetry; exploratory analysis. INTRODUÇÃOO uso de imagens digitais como ferramenta para análises químicas tem sido amplamente explorado nos últimos anos.1 Empregandose imagens obtidas por câmeras fotográficas, scanners, webcams ou telefones celulares, conhecidos como smartphones, é possível realizar determinações qualitativas e quantitativas com desempenho adequado, sem a necessidade de instrumentos como espectrofluorímetros ou espectrofotômetros.2-4 De fato, a literatura relata que, utilizando informações simples das imagens, como os valores de cores usualmente baseadas no sistema RGB (do inglês Red, Blue e Green) consegue-se obter resultados analíticos similares àqueles adquiridos com instrumentação já bem estabelecida, caracterizando esta estratégia em uma alternativa de menor custo para a realização de determinadas medidas instrumentais.Ao se considerar as aplicações analíticas que podem ser conduzidas por meio de imagens digitais, merece destaque aquelas que envolvem a identificação de substâncias ou a discriminação/ classificação de amostras baseadas em medidas colorimétricas. 5Neste sentido, arranjos com sensores contendo diferentes reagentes colorimétricos imobilizados sobre filmes poliméricos ou de papel têm sido aplicados com sucesso na resolução de muitos desafios analíticos, como a discriminação de explosivos ou de aminas e a identificação de substâncias de interesse variado como compostos orgânicos voláteis, produtos químicos tóxicos ou aromatizantes do café.6-11 Na maioria destas aplicações, imagens do arranjo de sensores, obtidas a...

show abstract

“…The use of digital imaging obtained from cost-effective WebCams, has been used as alternative to evaluate the colour variation during the acidic titrations with no relevant differences with colorimetric monitoring at the 95% level [37]. Another original alternative to spectrophotometric analysis was the use of a WebCam as a detector and as light source the computer monitor [38].…”

Section: Introductionmentioning

confidence: 99%