Incorporation of microencapsulated polyphenols from jabuticaba peel (Plinia spp.) into a dairy drink: stability, in vitro bioaccessibility, and glycemic response.

This work incorporated bioactives extracted from jabuticaba peel in the form of concentrated extract (JBE) and microencapsulated powders with maltodextrin (MDP) and gum arabic (GAP) in a dairy drink, evaluating its stability, in vitro bioaccessibility, and glycemic response. We evaluated the pH, acidity, colorimetry, total phenolics and anthocyanins, antioxidant capacity, degradation kinetics and half-life of anthocyanins, bioaccessibility, and postprandial glycemic physicochemical characteristics response in healthy individuals. The drinks incorporated with polyphenols (JBE, GAP, and MDP) and the control dairy drink (CDD) maintained stable pH and acidity over 28 days. In color, the parameter a*, the most relevant to the study, was reduced for all formulations due to degradation of anthocyanins. Phenolic and antioxidant content remained constant. In bioaccessibility, we found that after the gastrointestinal simulation, there was a decrease in phenolics and anthocyanins in all formulations. In the glycemic response, we observed that the smallest incremental areas of glucose were obtained for GAP and JBE compared to CDD, demonstrating that polyphenols reduced glucose absorption. Then, the bioactives from jabuticaba peel, incorporated into a dairy drink, showed good storage stability and improved the product's functional aspects.

Preparation of a Molecularly Imprinted Polymer on Polyethylene Terephthalate Platform Using Reversible Addition-Fragmentation Chain Transfer Polymerization for Tartrazine Analysis via Smartphone.

This work describes the preparation of a molecularly imprinted polymer (MIP) platform on polyethylene terephthalate (MIP-PET) via RAFT polymerization for analyzing tartrazine using a smartphone. The MIP-PET platform was characterized using Fourier transform infrared (FTIR) techniques, Raman Spectroscopy, X-ray photoelectron spectroscopy (XPS), and confocal microscopy. The optimal pH and adsorption time conditions were determined. The adsorption capacity of the MIP-PET plates with RAFT treatment (0.057 mg cm-2) was higher than that of the untreated plates (0.028 mg cm-2). The kinetic study revealed a pseudo-first-order model with intraparticle diffusion, while the isotherm study indicated a fit for the Freundlich model. Additionally, the MIP-PET demonstrated durability by maintaining its adsorption capacity over five cycles of reuse without significant loss. To quantify tartrazine, images were captured using a smartphone, and the RGB values were obtained using the ImageJ® free program. A partial least squares regression (PLS) was performed, obtaining a linear range of 0 to 7 mg L-1 of tartrazine. The accuracy of the method was 99.4% (4.97 ± 0.74 mg L-1) for 10 samples of 5 mg L-1. The concentration of tartrazine was determined in two local soft drinks (14.1 mg L-1 and 16.5 mg L-1), with results comparable to the UV-visible spectrophotometric method.

Modificação de uma resina composta Bulk Fill Flow com extrato acetônico da casca da romã / Modification of a Bulk Fill Flow composite resin with acetonic extract from pomegranate peel

Introdução: A cárie dentária ainda se constitui um problema de saúde pública. Áreas adjacentes a restaurações são frequentemente acometidas por cárie. Por mais que as resinas compostas estejam sendo estudadas e melhoradas, ainda não apresentam atividade antimicrobiana. As cascas da romã (Punica Granatum) são um recurso potencial para compostos bioativos como fenólicos, proantocianidinas e flavonoides, além de apresentarem atividade antioxidante e efeito inibitório contra bactérias Gram-negativas e Gram-positivas. Objetivo: modificar a resina composta Opus Bulk Fill Flow (FGM®) com o extrato acetônico da casca da romã em diferentes concentrações e avaliar a rugosidade da superfície e mudança de cor. Metodologia: foi realizada a extração de 5g de casca da romã utilizando 100mL de solvente acetona 70%. Após rotaevaporação, filtragem e liofilização do extrato, este foi macerado, peneirado e pesado em concentrações diferentes a partir da concentração inibitória mínima capaz de inibir o crescimento de Streptococcus mutans ATCC 700610. A resina composta Opus Bulk Fill Flow foi modificada com esse extrato em diferentes concentrações de forma a gerar 5 grupos: Controle 0 µg (n=10), G930 µg (n=10), G1860 µg (n=10), G3730 µg (n=10) e G7460 µg (n=10). Rugosidade (Ra), diferença de cor (ΔE00) e índice de brancura (WID) foram submetidos aos testes de normalidade. Os dados não-paramétricos de Ra foram submetidos ao teste de Kruskal-Wallis com pós-teste de Dunn e os dados paramétricos do ΔE00 e WID foram submetidos ao teste ANOVA 1 Fator com pósteste de Tukey por meio do software GraphPad Prism 8 e Microsoft Excel 2019. Resultados: Verificou-se que a média do índice de brancura (WID) diminuiu conforme o aumento da concentração do extrato na resina modificada (p<0,05), assim como, as resinas modificadas se tornaram, visivelmente a olho nu, um pouco mais amareladas. Após 1 mês, as amostras dos grupos experimentais sofreram a mesma variação de cor (ΔE00) que o grupo controle, uma vez que os valores das médias foram semelhantes. Portanto, todos os grupos apresentaram estabilidade de cor. A rugosidade superficial (Ra) não mostrou diferença estatisticamente significativa (p>0,05). Todos os grupos apresentaram médias com valores similares a 0,06µm. Conclusão: A alteração de cor na resina, com a inserção do extrato, ainda na maior concentração, se manteve na classificação do matiz A. O que não afeta as propriedades organolépticas e pode ser considerada uma cor similar à cor dos dentes naturais. A adição do extrato na resina manteve a rugosidade superficial de todos os grupos dentro do valor ideal, prevenindo a adesão de biofilmes e microrganismos e proporcionando conforto ao toque da língua (AU).

Introduction: Dental caries still constitutes a public health problem. Areas adjacent to restorations are often affected by caries. Even though resin composites are being studied and improved, they still do not have antimicrobial activity. Pomegranate peels (Punica Granatum) are a potential resource for bioactive compounds such as phenolics, proanthocyanidins and flavonoids, in addition to presenting antioxidant activity and inhibitory effects against Gram-negative and Gram-positive bacteria. Objective: to modify the Opus Bulk Fill Flow (FGM™) resin composite with the acetone extract of pomegranate peel in different concentrations and evaluate the surface roughness, and color change. Methodology: 5g of pomegranate peel was extracted using 100mL of 70% acetone solvent. After rotary evaporation, filtering and lyophilization of the extract, it was macerated, sieved and weighed at different concentrations based on the minimum inhibitory concentration capable of inhibiting the growth of Streptococcus mutans ATCC 700610. The Opus Bulk Fill Flow resin composite was modified with this extract in different concentrations to generate 5 groups: Control 0 µg (n=10), G930 µg (n=10), G1860 µg (n=10), G3730 µg (n=10) e G7460 µg (n=10). Roughness (Ra) and color difference (ΔE00) were subjected to normality tests and non-parametric data were subjected to the Kruskal-Wallis test with Dunn's post-test using GraphPad Prism 8 and Microsoft Excel 2019 software. Results: It was found that the average whiteness index (WID) decreased as the concentration of the extract in the modified resin increased (p<0.05), as well as the modified resins became, visibly to the naked eye, a little more yellowish. After 1 month, samples from the experimental groups suffered the same color variation (ΔE00) as the control group, since the average values were similar. Therefore, all groups showed color stability. Surface roughness (Ra) did not show a statistically significant difference (p>0.05). All groups presented average values similar to 0.06µm. Conclusion: The color change in the resin, with the insertion of the extract, even at the highest concentration, remained in the classification of hue A. This does not affect the organoleptic properties and can be considered a color similar to the color of natural teeth. The addition of the extract to the resin composite maintained the surface roughness of all groups within the ideal value, preventing the adhesion of biofilms and microorganisms and providing comfort to the touch of the tongue (AU).

Feasibility of using colorimetric devices for whole and ground coffee roasting degrees prediction.

BACKGROUND: Coffee roasting is one of the crucial steps in obtaining a high-quality product as it forms the product's color and flavor characteristics. Roast control is made by visual inspection or traditional instruments such as the Agtron spectrophotometer, which can have high implementation costs. Therefore, the present study evaluated colorimetric approaches (a bench colorimeter, smartphone digital images, and a colorimetric sensor) to predict the Agtron roasting degrees of whole and ground coffee. Two calibration approaches were assessed, that is, multiple linear regression and least-squares support vector machine. For that, 70 samples of whole and ground roasted coffees comprising the Agtron roasting range were prepared. RESULTS: The results showed that all three colorimetric acquisition types were efficient for the model building, but the bench colorimeter and the smartphone digital images generally performed with good determination coefficients and low errors as measured by external validation. For the whole bean coffee, the best model presented a determination coefficient (R2) of 0.99 and a root-mean-squared error (RMSE) of 1.91%, while R2 of 0.99 and RMSE of 0.87% was obtained for ground coffee, both using the colorimeter. CONCLUSION: The obtained models presented good prediction capability, as assessed by external validation and randomization tests. The obtained findings point to an alternative for coffee roasting monitoring that can lead to higher digitalization and local control of the process, even for smaller producers, due to its lower costs. © 2024 Society of Chemical Industry.

Cost-effective smartphone-based method for low range chemical oxygen demand analysis.

Aiming the decentralization of monitoring policies and to facilitate the work of researchers, mainly in developing countries, the present method deals with the explanation of a simple and rapid protocol for chemical oxygen demand (COD) analysis through the use of digital smartphone devices coupled with a camera and a free app available for Android operating system that recognizes HSV (hue, saturation, value). The calibration of the method is done based on the theoretical values of potassium hydrogen phthalate for a proper and reliable build of the calibration curve by using the smartphone-based technique and the digested samples of COD. The coefficient of determination (R2) attained a value upper than 0.99, providing a high confidence levels, and the method achieved 97% of average accuracy in samples with COD values ranging from 0 to 150 mg L-1. Finally, the procedure here presented can be a great support for scientific laboratories and monitoring policies, once it can efficiently substitute expensive spectrophotometers and can improve and ensure the sustainable management of water sanitation, which is one of the sustainable goals proposed by the United Nations.•COD measurements, based on the use of a simple smartphone with a camera, can be a promising way for environmental analysis when spectrophotometers are not available, such as decentralized approaches.•The use of smartphone protocol is a novel initiative to fulfill sustainable development goal 6 on clean water and sanitation.•The smartphone is capable to read the difference of HSV values efficiently and can substitute the use of expensive spectrophotometers.

Paper-based analytical devices for point-of-need applications.

Paper-based analytical devices (PADs) are powerful platforms for point-of-need testing since they are inexpensive devices fabricated in different shapes and miniaturized sizes, ensuring better portability. Additionally, the readout and detection systems can be accomplished with portable devices, allying with the features of both systems. These devices have been introduced as promising analytical platforms to meet critical demands involving rapid, reliable, and simple testing. They have been applied to monitor species related to environmental, health, and food issues. Herein, an outline of chronological events involving PADs is first reported. This work also introduces insights into fundamental parameters to engineer new analytical platforms, including the paper type and device operation. The discussions involve the main analytical techniques used as detection systems, such as colorimetry, fluorescence, and electrochemistry. It also showed recent advances involving PADs, especially combining optical and electrochemical detection into a single device. Dual/combined detection systems can overcome individual barriers of the analytical techniques, making possible simultaneous determinations, or enhancing the devices' sensitivity and/or selectivity. In addition, this review reports on distance-based detection, which is also considered a trend in analytical chemistry. Distance-based detection offers instrument-free analyses and avoids user interpretation errors, which are outstanding features for analyses at the point of need, especially for resource-limited regions. Finally, this review provides a critical overview of the practical specifications of the recent analytical platforms involving PADs, demonstrating their challenges. Therefore, this work can be a highly useful reference for new research and innovation.

Ethnic variation in the most common shade of anterior teeth among malaysian students: a cross-sectional study / Variación del tono más común de los dientes anteriores entre estudiantes malasios de diferentes etnias: un estudio transversal

Aim: Determination of the most common shade of anterior teeth in Malaysian students of different ethnicities. Materials and Methods: A total of 120 subjects, 40 each from different ethnicities (Malay, Chinese, and Indian) aged 18-22 years were evaluated for tooth shade using the VITA Classical shade guide. The subject was asked to sit in an up-right position with teeth at the clinician's eye level and the subject was instructed to remove makeup or tinted eyewear which may affect the result. The procedure was done in natural daylight. The shade tabs were positioned adjacent to the maxillary central incisor and the middle 1/3rd of the facial surface was assessed by experts to determine the correct tooth shade. The data was statistically analysed. Results: The differences in tooth shade were seen among the subjects of different ethnicities. The Malay ethnicity has B1 (37%) as the most common tooth shade whereas Chinese has C1 (27%) and Indian C1 (40%). Conclusions: Under the limitation of the study, it was found that there is a relationship between tooth color and ethnic background. Malay students tend to have brighter teeth as compared to Chinese and Indian students.

Objetivo: Determinar el tono más común de los dientes anteriores en estudiantes malasios de diferentes etnias. Materiales y Métodos: Se evaluó el color de los dientes de un total de 120 sujetos, 40 de diferentes etnias (malayos, chinos e indios) de edades comprendidas entre 18 y 22 años, utilizando la guía de colores VITA Classical. Se pidió al sujeto que se sentara en posición vertical con los dientes al nivel de los ojos del médico y se le indicó que se quitara el maquillaje o las gafas teñidas, lo que podría afectar el resultado. El procedimiento se realizó con luz natural. Las pestañas de color se colocaron adyacentes al incisivo central superior y expertos evaluaron el tercio medio de la superficie facial para determinar el tono correcto del diente. Los datos fueron analizados estadísticamente. Resultados: Se observaron diferencias en el color de los dientes entre los sujetos de diferentes etnias. La etnia malaya tiene el B1 (37%) como el color de dientes más común, mientras que los chinos tienen el C1 (27%) y los indios C1 (40%). Conclusión: Bajo las limitaciones del estudio, se encontró que existe una relación entre el color de los dientes y el origen étnico. Los estudiantes malayos tienden a tener dientes más brillantes en comparación con los estudiantes chinos e indios.

"Do it yourself" protocol to fabricate dual-detection paper-based analytical device for salivary biomarker analysis.

This paper describes the design and construction of dual microfluidic paper-based analytical devices (dual-µPADs) as a lab-on-paper platform involving a "do-it-yourself" fabrication protocol. The device comprises a colorimetric and electrochemical module to obtain a dual-mode signal readout sensing strategy. A 3D pen polymeric resin was used to prepare graphite carbon-based electrodes and hydrophobic barriers on paper substrates. The proposed carbon-based ink was employed to manufacture electrodes on paper based on a stencil-printing approach, which were further characterized by electrochemical and morphological analyses. The analytical performance of the dual-µPADs was simultaneously evaluated for lactate, pH, nitrite, and salivary amylase (sAA) analysis. To demonstrate the proof-of-concept, saliva samples collected from both healthy individuals and those with periodontitis were successfully tested to demonstrate the feasibility of the proposed devices. Samples collected from individuals previously diagnosed with periodontitis showed high levels of nitrite and sAA (> 94 µmol L-1 and > 610 U mL-1) in comparison with healthy individuals (≤ 16 µmol L-1 and 545 U mL-1). Moreover, periodontitis saliva resulted in acid solution and almost null lactate levels. Notably, this protocol supplies a simple way to manufacture dual-µPADs, a versatile platform for sensitive detecting of biomarkers in saliva playing a crucial role towards the point-of-care diagnosis of periodontal disease.

Environmental application of a cost-effective smartphone-based method for COD analysis: Applicability in the electrochemical treatment of real wastewater.

This study aims to develop a cheap method for the evaluation of quality of water or the assessment of the treatment of water by chemical oxygen demand (COD) measurements throughout the use of the HSV color model in digital devices. A free application installed on a smartphone was used for analyzing the images in which the colors were acquired before to be quantified. The proposed method was also validated by the standard and spectrophotometric methods, demonstrating that no significant statistical differences were attained (average accuracy of 97 %). With these results, the utilization of this smartphone-based method for COD analysis was used/evaluated, for first time, by treating electrochemically a real water matrix with substantial organic and salts content using BDD and Pt/Ti anodes. Aiming to understand the performance of both anodes, bulk experiments were performed under real pH by applying current densities (j) of 15, 30, and 60 mA cm-2. COD abatement results (which were achieved with this novel smart water security solution) clearly showed that different organic matter removal efficiencies were achieved, depending on the electrocatalytic material used as well as the applied current density (42 %, 45 %, and 85 % for Ti/Pt while 93 %, 97 % and total degradation for BDD by applying 15, 30, and 60 mA cm-2, respectively). However, when the persulfate-mediated oxidation approach was used, with the addition of 2 or 4 g Na2SO4 L-1, COD removal efficiencies were enhanced, obtaining total degradation with 4 g Na2SO4 L-1 and by applying 15 mA cm-2. Finally, this smartphone imaging-based method provides a simple and rapid method for the evaluation of COD during the use of electrochemical remediation technology, developing and decentralizing analytics technologies for smart water solutions which play a key role in achieving the Sustainable Development Goal 6 (SDG6).

Technique for Darkening of Extracted Teeth Simulating Pulpal Necrosis Discoloration.

Background: The use of discolored teeth is required to test whitening products, and it is difficult to obtain them, given their scarcity. Objective: To present a technique for in vitro darkening of extracted teeth simulating pulpal necrosis discoloration. Materials and Methods: Hemolysates I and II from human blood were subjected or not to laser irradiation (442 nm) for 1 h. The concentration of oxyhemoglobin (O2Hb) was analyzed by ultraviolet/visible spectroscopy, and the conversion of O2Hb to methemoglobin (MetHb) by transmission spectroscopy was assessed immediately and after 3 and 40 days. For darkening evaluation, bovine incisors were divided into two groups (n = 25), and their pulp chambers were filled with hemolysate solution II (HSII) and hemolysate II solution + laser (HSII+L). After storage in artificial saliva for 40 days at 37°C, color changes were measured by a colorimeter and ΔE was compared with the NBS parameters. Data were analyzed using a mixed linear model (α=5%). Results: HSII+L presented the lowest O2Hb and higher MetHb. The conversion of O2Hb to MetHb in HSII+L was 42% higher than in HSII. Both groups were effective in darkening the teeth, according to the NBS. Darkening stabilized from day 35. HSII promoted a marked color difference. Conclusion: The proposed technique was effective in darkening the extracted teeth simulating necrosis discoloration for in vitro models.

Associations between Integument Color and Physical and Physiological Quality in Pterodon pubescens Seeds.

Pterodon pubescens is a native Brazilian species typical of the cerrado biome, belonging to the Leguminosae-Papilionoideae (Fabaceae) family and popularly known as sucupira branca or faveiro. Its seeds exhibit different integument colors, which may exhibit a direct association to physiological quality related to higher germination percentage rates, vigor, and germination speed index (GSI). Therefore, selection and evaluation methods concerning P. pubescens seed quality are required for the preservation of this species. In this context, the aim of the present study was to determine the relationship between P. pubescens seed integument color and seed quality, through a combination of radiographic imaging and physiological, histochemical and biochemical assays. P. pubescens seeds were obtained from five matrices, and visually classified into four color classes, yellow, light brown, dark brown and black. The coordinates "L", "a" and "b", indicated by the colorimeter and the calculations of the chroma and hue angle values, verified that there was a difference in the color of the seeds, eliminating the subjectivity of the visual classification. Thus, the clearer the integuments, the greater their density, filling and α-amylase and ß-amylase hydrolytic enzyme activities, the latter comprising important germination power indicators, in addition to high ascorbate peroxidase (APX) enzyme activities, responsible for hydrogen peroxide (H2O2) elimination. Because of this, lighter colored seeds led to higher vigor, germination and GSI rates. The removal of darker seeds from P. pubescens seed lots guarantees higher germination rates and vigor of new plants in nurseries destined to recompose P. pubescens populations.

A Rapid RT-LAMP Assay for SARS-CoV-2 with Colorimetric Detection Assisted by a Mobile Application.

Loop-mediated amplification has been promoted for SARS-CoV-2 screening, however, antigen tests are preferred in low-income countries and remote zones. Poor training in molecular biology, plus the need for RNA purification or reading instruments to overcome issues of sensitivity in colorimetric detection, are some of the reasons limiting the use of this technique. In this study, nasopharyngeal swabs, aspirates and saliva were amplified in an in-house LAMP assay and subject to colorimetric detection, achieved by the naked eye and by image analysis with a mobile application. Accuracy of detection by the naked eye ranged from 61-74% but improved to 75-86% when using the application. Sensitivity of the digital approach was 81% and specificity 83%, with poor positive predictive value, and acceptable negative predictive value. Additionally to the reported effect of some transport media's pH, the presence of mucus and warming up of reagents while setting up the reaction critically affected performance. Accuracy per type of sample was 55, 70 and 80%, for swabs, aspirates and saliva, respectively, suggesting potential to improve the test in saliva. This assay, carried out in a closed tube, reduces contamination, has few pipetting steps and requires minimal equipment. Strategies to improve performance and implications of the use this sort of colorimetric LAMP for massive testing are discussed.

Current Challenges and Future Trends of Enzymatic Paper-Based Point-of-Care Testing for Diabetes Mellitus Type 2.

A point-of-care (POC) can be defined as an in vitro diagnostic test that can provide results within minutes. It has gained enormous attention as a promising tool for biomarkers detection and diagnosis, as well as for screening of chronic noncommunicable diseases such as diabetes mellitus. Diabetes mellitus type 2 is one of the metabolic disorders that has grown exponentially in recent years, becoming one of the greatest challenges to health systems. Early detection and accurate diagnosis of this disorder are essential to provide adequate treatments. However, efforts to reduce incidence should remain not only in these stages but in developing continuous monitoring strategies. Diabetes-monitoring tools must be accessible and affordable; thus, POC platforms are attractive, especially paper-based ones. Paper-based POCs are simple and portable, can use different matrixes, do not require highly trained staff, and are less expensive than other platforms. These advantages enhance the viability of its application in low-income countries and hard-to-reach zones. This review aims to present a critical summary of the main components required to create a sensitive and affordable enzymatic paper-based POC, as well as an oriented analysis to highlight the main limitations and challenges of current POC devices for diabetes type 2 monitoring and future research opportunities in the field.

The combined use of systemic analgesic/anti-inflammatory drugs and a bioactive topical desensitizer for reduced in-office bleaching sensitivity without jeopardizing the hydrogen peroxide efficacy: a randomized, triple blinded, split-mouth clinical trial.

OBJECTIVE: To evaluate the effect of combined systemic administration of paracetamol 500 mg/codeine phosphate 30 mg (PACO) and postoperative topical application of a bioactive desensitizer on in-office bleaching sensitivity and tooth color change. MATERIALS AND METHODS: A randomized, triple-blind, split-mouth clinical trial was conducted. Forty volunteers ingested PACO (n = 20) or placebo (PLA) (n = 20). Their left/right hemiarches received topical application of a bioactive desensitizer [Nano-P™(NP)] and prophylactic paste (PAS), generating four treatment approaches: PACO/NP, PACO/PAS, PLA/NP, and PLA/PAS. Two bleaching sessions (35% hydrogen peroxide) were performed, and the PAS/NP were applied after the procedure. Sensitivity was obtained since the first bleaching session up to 7 days post-bleaching. The color change was evaluated using CIEDE2000 and whiteness index parameters up to 7 days post-bleaching. Data were analyzed using one- and two-way ANOVA/Tukey post hoc tests (p < 0.05). RESULTS: The PLA/PAS showed a sensitivity average of at least two times higher than the PACO/NP. The treatment approaches promoted statistically similar bleaching patterns (p > 0.05). CONCLUSION: The combined approach of systemic administration of PACO and postoperative topical application of NP reduced the level of in-office bleaching sensitivity without jeopardizing hydrogen peroxide efficacy. CLINICAL RELEVANCE: Professionals can adopt the combined approach of systemic administration of analgesic/anti-inflammatory drugs and topical application of a bioactive desensitizer for decreased bleaching sensitivity caused by 35% hydrogen peroxide in-office.

Evaluation of the Whitening Effectiveness of Violet Illumination Alone or Combined with Hydrogen Peroxide Gel.

Objective: To evaluate the effectiveness of the whitening and washing steps of a treatment using violet illumination (VI) alone or combined with hydrogen peroxide gel. In addition, we evaluated the color change after cleaning the tooth with and without mineral oil. Methods: First, 16 bovine teeth were extracted and stored in 5% thymol solution. Next, the teeth were collected and cleaned. Then, the teeth were stained with instant coffee solution for 24 h. The teeth were divided in four groups: control, VI without 35% hydrogen peroxide gel (VI), VI with 35% hydrogen peroxide gel (VI + gel), and VI without 35% hydrogen peroxide gel and cleaned with mineral oil before washing (VI + oil). Results: The whitening treatment VI + gel was able to completely restore the teeth whiteness and make the teeth 31.2% less yellow than prior coffee staining. The VI + oil treatment led to about 3.7 times the whiteness and yellowness changes observed in the VI treatment and restored 51% of the whiteness lost by staining. Conclusions: The VI + gel treatment can be recommended against coffee stains and should be further investigated for other types of tooth stains. In addition, cleaning the tooth surface with mineral oil could be an alternative to increase the performance of whitening treatments.

Fruit quality of wild, sweet and yellow passion fruit genotypes in Distrito Federal, Brazil

Despite the importance of passion fruit for the Brazilian fruit market, there are still many agronomic and fruit quality problems to be solved, in order to increase this crop performance. The objective of this study was to evaluate the quality of twelve genotypes of wild, sweet and yellow passion fruit, aiming to identify promising materials considering fruit quality, in Federal District, Brazil. An experiment was carried out at the Água Limpa Farm of the Universidade de Brasília (UnB) from 2016 to 2018, in a randomized block design, with 12 treatments, 4 replicates and 6 plants/plot. At the harvesting time, six fruits per plot were randomly collected for the following physicochemical analysis: fruit mass, pulp mass with and without seeds, length/longitudinal diameter, width/transverse diameter, length/width ratio, husk thickness, predominant color of the pulp (L*, C*, h*), number of seeds, seed size, total soluble solids content, total titratable acidity, total soluble solids/total titratable acidity ratio and pH. High heritability values ​​and relation of genetic/environment variation coefficients ratio were observed for most of the characteristics evaluated. The genotypes of yellow passion fruit MAR20#21 P2 x FB 200 P1 R2 and MAR20#19 ROXO R4 x ECRAM P3 R3 showed the best characteristics of fruit mass and pulp mass with seed. All the genotypes studied showed values ​​of total soluble solids above 11ºBrix. Positive and significant correlation was observed between fruit mass and length/width ratio, indicating that oblong fruits have higher fruit mass.

A novel direct-immersion single-drop microextraction combined with digital colorimetry applied to the determination of vanadium in water.

In this study, a method based on direct-immersion single-drop microextraction was developed for the determination of vanadium in water. The detection system uses digital images obtained directly from the solvent drop after the sorption of V(V). The extraction solvent used was the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate ([C6MIM][PF6]). The images were obtained directly from the solvent drop, with the aid of a camera. The digital images were stored, and the RGB (red, green, and blue) data were obtained. The data collected by the red channel were used to construct the analytical curve since it showed higher sensitivity compared with green and blue channels. Under optimized conditions, the method presented an enrichment factor of 50 and a limit of detection of 0.6 µg L-1 for 3.5 mL sample volume. The limit of quantification and the relative standard deviation (50.0 µg L-1) obtained were 1.8 µg L-1 and 4.8%, respectively. Certified reference material (Plankton) was used to assess the accuracy of the method. The simple, fast, efficient, and low-cost procedure was successfully applied to the determination of V(V) in water samples. The proposed method is also following the principles of green chemistry since it uses minimal volumes of samples, reagents, and solvents and yields a small amount of waste.

Resistance Sources and Antixenotic Factors in Brazilian Bean Genotypes Against Bemisia tabaci.

Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Middle East Asia Minor 1 is one of the most important pests of the common bean, due to its potential of causing direct and indirect damage. This study aimed to evaluate 78 bean genotypes to verify the occurrence of resistance of antixenosis type against B. tabaci. Initially, multiple-choice trials were performed to evaluate the oviposition preference and nymphs' establishment at 3 and 15 days after infestation. Subsequently, 21 bean genotypes were selected, and a no-choice test was conducted. Colorimetric analyses were performed to establish correlations between leaf color and insect establishment. In multiple-choice trial, the genotypes BRS Ametista, BRS Estilo, BRS Esplendor, SCS 204 Predileto, BRS Notável, IPR Eldorado, CHIB 06, IPR Quero-Quero, Iapar 81, CHIP 338, IPR Garça, Arcelina 4, SCS 202 Guará, IAC Esperança, H96102-1-1-1-52, CHIP 348, Carioca Comum, CHIP 300, IAC Carioca Eté, IAC Ybaté, and Tybatã were the least used for oviposition and nymph establishment, demonstrating antixenosis or antibiosis. In the no-choice trial, most genotypes were less attractive to whitefly, and the genotypes CHIB 06, IPR Garça, CHIP 300, and IAC Esperança had less oviposition. The most attractive genotypes presented high luminosity and more intense green and yellow colors, indicating positive correlation. Therefore, the genotypes BRS Ametista, SCS 204 Predileto, BRS Estilo, IPR Eldorado, SCS-202 Guará, Carioca Comum, Arcelina 4, CHIP 348, and IAC Esperança showed the highest resistance stability in the no-choice trial, and they are promising sources of antixenotic factors for use in breeding programs to obtain whitefly-resistant common bean lines.

Evaluación de susceptibilidad en cándidas spp por colorimetría obtenida en gestantes de un hospital obstétrico / Susceptibility evaluation in candida spp by colorimetry obtained in pregnant women from an obstetric hospital / Avaliação da suscetibilidade em cândida spp por colorimetria obtida em gestantes de um hospital obstétrico

INTRODUCCIÓN: las infecciones fúngicas ocasionadas por levaduras del género Cándida son extremadamente comunes en mujeres de edad reproductiva, y constituyen un motivo de atención medica de salud. OBJETIVO: evaluar la susceptibilidad de Cándidas spp, mediante el método colorimétrico (Integral Yeast System Plus). MÉTODO: fue de tipo descriptivo, transversal; se recopiló información mediante observación directa en campo y el análisis documental para obtener información bibliográfica de tipo secundaria. RESULTADOS: de los 72 casos encontrados de Cándida Albicans revela que son susceptibles a la anfotericina B (2ug/ml); de los 5 casos encontrados de Cándida Krusei revela que son sensibles a la Anfotericina B (2ug/ml); De 1 caso encontrado de Cándida Parapsilosis revela sensibilidad en la Nistatina (1.25ug/ml). En este estudio la prevalencia de la infección por Cándida fue del (44.98%). CONCLUSIONES: Cándida Albicans fue la especie más común aislada en las mujeres embarazadas representando un 72%, En la evaluación de la susceptibilidad a través del kit Integral System Yeast Plus se obtuvo que Cándida Albicans es susceptible a Anfotericina B, Flucitosina entre otros, en Cándida Glabrata se obtuvo que es sensible a la Nistatina, Anfotericina B, susceptible entre otros, en Cándida Krusei se obtuvo que es sensible a la Anfotericina B, Clotrimazol, Miconazol, susceptibles a la Nistatina, Voriconazol y resistente a la Flucitosina, Ketoconazol, Itraconazol y Fluconazol.

INTRODUCTION: fungal infections caused by yeast of the genus Candida are extremely common in women of reproductive age, and constitute a reason for medical health care. OBJECTIVE: to evaluate the susceptibility of Candida spp, using the colorimetric method (Integral Yeast System Plus). METHOD: it was descriptive, transversal; Information was collected through direct observation in the field and documentary analysis to obtain secondary bibliographic information. RESULTS: of the 72 cases found, Candida Albicans reveals that they are susceptible to amphotericin B (2ug / ml); of the 5 cases found, Candida Krusei reveals that they are sensitive to Amphotericin B (2ug / ml); Of 1 case found of Candida Parapsilosis reveals sensitivity in Nystatin (1.25ug / ml). In this study, the prevalence of Candida infection was (44.98%). CONCLUSIONS: Candida Albicans was the most common species isolated in pregnant women, representing 72%. In the evaluation of susceptibility through the Integral System Yeast Plus kit it was obtained that Candida Albicans is susceptible to Amphotericin B, Flucytosine among others, in Candida Glabrata was obtained that it is sensitive to Nystatin, Amphotericin B, susceptible among others, in Candida Krusei it was obtained that it is sensitive to Amphotericin B, Clotrimazole, Miconazole, susceptible to Nystatin, Voriconazole and resistant to Flucytosin, Ketoconazole, Itraconazole and Fluconazole.

INTRODUÇÃO: as infecções fúngicas causadas por leveduras do gênero Candida são extremamente comuns em mulheres em idade reprodutiva e constituem motivo de cuidados médicos. OBJETIVO: avaliar a suscetibilidade de Candida spp, por meio do método colorimétrico (Integral Yeast System Plus). MÉTODO: foi descritivo, transversal; as informações foram coletadas por meio de observação direta em campo e análise documental para obtenção de informações bibliográficas secundárias. RESULTADOS: Dos 72 casos encontrados, Cândida Albicans revelou ser suscetíveis à anfotericina B (2ug /ml); dos 5 casos encontrados, Candida Krusei revela que são sensíveis à Anfotericina B (2ug / ml); de 1 caso encontrado de Candida Parapsilosis revela sensibilidade na Nistatina (1,25ug / ml). Neste estudo, a prevalência de infecção por Candida foi (44,98%). CONCLUSÕES: Cândida Albicans foi a espécie mais comum isolada em gestantes, representando 72%. Na avaliação da susceptibilidade através do kit Integral System Yeast Plus foi obtido que Candida Albicans é suscetível à Anfotericina B, Flucitosina entre outras, em Cândida Glabrata foi obtido que é sensível a Nistatina, Anfotericina B, suscetível entre outras, em Candida Krusei foi obtido que é sensível a Anfotericina B, Clotrimazol, Miconazol, suscetível a Nistatina, Voriconazol e resistente a Flucitosina, Cetoconazol, Itraconazol e Fluconazol.

Novel approaches for colorimetric measurements in analytical chemistry - A review.

Colorimetric techniques have been developed and used in routine analyses for over a century and apparently all their potentialities have been exhaustively explored. However, colorimetric techniques have gained high visibility in the last two decades mainly because of the development of the miniaturization concept, for example, paper-based analytical devices that mostly employ colorimetric reactions, and by the advances and popularity of image capture instruments. The impressive increase in the use of these devices was followed by the development and enhancement of different modes of color detection to meet the demands of making qualitative, semi-quantitative, and fully quantitative analyses of multiple analytes. Cameras, scanners, and smartphones are now being used for this purpose and have become suitable alternatives for different approaches to colorimetric analysis; this, in addition to advancements in miniaturized devices. On the other hand, recent developments in optoelectronics technologies have launched more powerful, more stable and cheaper light-emitting diodes (LEDs), which once again have become an interesting tool for the design of portable and miniaturized devices based on colored reactions. Here, we present a critical review of recent developments and challenges of colorimetric detection in modern analytical chemistry in the last five years, and present thoughts and insights towards future perspectives in the area to improve the use of colorimetric detection in different application approaches.