Group 4Karimatul AiniSylvia AnggraeniRetno Dwi P.Nurvita Wahyu K.

Metric Units*

Light PropertiesWavelength

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Polarity*Light is a waveFilters can block waves in off axis planes

Waves can be added*++==

Light PropertiesResolution

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Wavelength/Resolution Interaction*

Light PropertiesReflection

Transmission*

Light PropertiesAbsorption

Refraction*bending

Light Microscopy TypesCompoundBright Field

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Oil immersion*With oilwithoutSome info lostOil with intermediaterefractive index

Microscopy Dark Field

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Microscopy Phase ContrastDual Beam*

Phase contrast Phase-contrast microscopy was invented in 1936 by Frits Zernike, a Dutch mathematical physicist. It is based on the principle that cells differ in refractive index (a factor by which light is slowed as it passes through a material) from their surroundings. Light passing through a cell thus differs in phase from light passing through its surroundings. This subtle difference is amplified by a device in the objective lens of the phase-contrast microscope called the phase ring, resulting in a dark image on a light background (Figure 2.5b). The ring consists of a phase platethe key discovery of Zernikethat amplifies the minute variation in phase. Zernikes discovery of differences in contrast between cells and their background stimulated other innovations in microscopy, such as fluorescence and confocal microscopy (discussed below). For his invention of phase-contrast microscopy, Zernike was awarded the 1953 Nobel Prize in Physics.*

Microscopy DICDifferential Interference Contrast

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DIC differential interference contrast*Similar to phase contrast, but input light is polarized

Microscopy FluorescenceUltraviolet light

*flourescein

Advantages of fluorescence*Can use specialized chemical probes that target specific features and then tag with fluorescent dyes Downside: must use expensive filters and excitory frequencies

Microscopy ConfocalConfocal

*Allows 3 dimensional viewingAllows multiple dyes to be overlaid

Confocal microscopy*Allows 3 dimensions

Combined confocal and fluorescence*Antibody labeling

Microscopy ImagingDigital

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Fig. 2-15*

Electron MicroscopyTransmission (TEM)

Scanning (SEM)

Scanning Tunneling (STM)*

TEM*Most popular for bacteria. Allows imaging internal features, but requires heavy metalstaining.

Electron Microscopy Images*

Microscopy TechniquesWet MountsSmearsStaining*

100SlideDry in airFlood slide with stain;rinse and dryPlace drop of oil onslide; examine with 100objective lensSpread culture in thinfilm over slidePass slide throughflame to heat fixOilI. Preparing a smearIII. MicroscopyII. Heat fixing and staining

Staining cells - increases contrast*Simple stain - one dye - shows size, shape, and arrangementMethylene blue - yeastCheek cell

Common stains*Safranin (*basic, + charge)Crystal violetred

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Differential stains*Use multiple dyes or dyes that interact with organisms differently.Primary stain / counterstain

Gram StainGram Stain The single most important stain in microbiology. Set the initial taxonomy of bacteria.Crystal violet *(basic stain)

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Gram Stain*

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Acid Fast Stain*Carbol-fuchsin stains acid fast organisms

Acid FastThe Ziehl-Neelsen stain, also known as the acid-fast stain, was first described by two German doctors; Franz Ziehl (1859 to 1926), a bacteriologist and Friedrich Neelsen (1854 to 1894), a pathologist. It is a special bacteriological stain used to identify acid-fast organisms, mainly Mycobacteria. Mycobacterium tuberculosis is the most important of this group, as it is responsible for the disease called tuberculosis (TB). It is helpful in diagnosing Mycobacterium tuberculosis since its lipid rich cell wall makes it resistant to Gram stain. It can also be used to stain few other bacteria like Nocardia. The reagents used are Ziehl-Neelsen carbolfuchsin, acid alcohol and methylene blue.*

Acid Fast of Mycobacterium tuberculosis*

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Negative Stain*Sometimes referred to as capsular stainIndia ink or nigrosin

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Flagellar Stain

*Salmonella typhimurium

Endospore StainUsed on spore forming bacteria such as Bacillus sp.*Malachite greenstains spores

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WASSALAMUALAIKUMTHANK YOU *

Bisa menggunakan kimia khusus target itu selidiki spesifik features kemudian pijar tag dengan: sisi buruknya zat pewarna harus menggunakan penyaring dan mahal rentang frekuensi excitory**