Spectra magic nx

The pH of all cream samples was measured at room temperature (21 ± 2 °C) in triplicate with a glass electrode (pH electrode 50 14, Crison Instruments, S.A., Barcelona, Spain).
The color was assessed using a Konica Minolta CM 2300d (Konica Minolta, Osaka, Japan) spectrophotometer on three random spots per sample, recorded according to the CIELab system, and the data were processed with the SpectraMagicTM NX software (Konica Minolta, Osaka, Japan). The obtained parameters were L*-lightness, a*-redness, and b*-yellowness. The total color difference (ΔE*) was calculated using Equation (1) [16 (link)].

where ΔE* is the total color change between a sample and the control (initial values identified with the subscript “0”).

To measure the colour of the developed colouring formulations, a colourimeter (model CR-400, Konica Minolta Sensing, Inc., Osaka, Japan) equipped with specific tool for granular materials (model CR-A50) was used as reported by the authors Pereira et al. [17 (link)]. The analysis of the colour parameters was made in the CIE L*a*b* colour space, through the illuminant C and the diaphragm aperture was 8 mm. The obtained data were analyzed using a “Spectra Magic Nx” (version CM-S100W 2.03.0006 software, Konica Minolta). The colour measurements were achieved after preparing the colorant preparation (t0) and every 4 weeks of storage, until it reached 12 weeks of shelf life.

The evaluation of the colorant potential of the extract was carried out by measuring the colour and the measurement of the colouring compounds by chromatography, in order to corroborate the data provided by the MRS. The colour was measured using a colorimeter (model CR-400, Konica Minolta Sensing, Inc., Osaka, Japan) with an adapter for granular materials (model CR-A50), according to a procedure described by Pereira et al. [24 (link)]. The measurements were made in the CIE L*a*b* colour space, using the illuminant C and a diaphragm aperture of 8 mm. Data were processed with the “Spectra Magic Nx” (version CM-S100W 2.03.0006 software, Konica Minolta). Quantitation of anthocyanin compounds was accomplished by chromatography using an HPLC-DAD-ESI/MS system as described in Section 3.4.

Color changes on the polished dentin surfaces (Fig. 1, assessment side) were assessed using a black/white-calibrated spectrophotometer (Konica Minolta CM-2600d, Tokyo, Japan) connected to an external computer running the analysis software (Spectra Magic NX, version 2.8, Konica Minolta). Specimens were positioned on the device using a customized aluminum holder so that they could be reassessed in the exact same position. Measurements were performed in the CIELAB color space in reflectance mode, where the L* value indicates the white to black, a* the green to red, and b* the blue to yellow hue. Images were taken with a field of view of 3 mm (Target Mask A147, Konica Minolta) under simulated natural light illumination (D65). Raw data were used for further analysis. Measurements were performed in triplicates at baseline, after blood staining, and at different time points during irrigation (see below).

A Konica Minolta CM-5 spectrophotometer was used to determine the colour of dried and homogenized sediment samples by detecting the diffused reflected light under standardized observation conditions (2° Standard Observer, Illuminant C). Colour spectra were obtained in the visible range (360 to 740 nm), in 10 nm increments, and these data were then converted into the Munsell colour system and the CIELAB Colour Space (L*a*b*) using the Konica Minolta SpectraMagic NX software. The resultant values indicate the extinction of light on a scale from L* 0 (absolute black) to L* 100 (absolute white), and express colour as chromaticity coordinates on red-green (a*) and blue-yellow (b*) scales.