Negative staining is a powerful preparative method for studying particulate specimens. In principle, the specimen is surrounded by heavy metal atoms that act as an electron barrier. Because the ...

In contrast to direct stains that bind to bacteria directly, a negative stain colors the background of a smear rather than the bacteria. These stains have negatively charged functional groups so they ...

The cell wall of most bacteria has an overall net negative charge and thus can be stained directly with a single basic (positively charged) stain or dye. This type of stain allows us to observe the ...