Biological stains dramatically improve specimen

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A wide variety of synthetic and naturally occurring biological dyes are available to the microscopist for selective staining of intracellular organelles in cells and tissues. Biological stains dramatically improve specimen contrast in brightfield illumination, and have been utilized for many years in histological preparations targeted at studies in anatomy, pathology, physiology, and similar disciplines. Compare the information contained in this section on the visible light absorption spectral data for common biological stains to determine suitability for use in black & white and color photomicrography and digital imaging.Typical visible light absorption spectra for red (Congo Red), green (Malachite Green), and blue (Methylene Blue) dyes . In this figure, absorption (diffuse density) is plotted as a function of wavelength from 300 to 700 nanometers. Congo Red has a strong absorption band at 340 nanometers in the near-ultraviolet region and another at 500 nanometers near the blue-green transition region. This dye transmits red wavelengths above 560 nanometers and thus, appears red to the eye. Appearing visually as a green dye, Malachite Green has a strong absorption band centered at 600 nanometers near the yellow-red transition region, with a wide transmission band (passing blue and green light) between 400 and 550 nanometers. Methylene blue has a strong absorption band centered at 660 nanometers, in the red region of the visible spectrum, and transmits wavelengths below 600 nanometers, bestowing a blue color to the dye. References: Chapter Three Methodology
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First of all, all the materials are gathered needed in the project. The one hundred grams (100 g) of mayana leaves is measured using a platform balance and it is crushed using a washed mortar and pestle. The crude extract is filtered with the use of filter paper. Funnel is used to transfer the crude extract in a small bottle with a tight cover.
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