The Basics of Microscope Slides

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The Basics of Microscope Slides - SmartLabs

A microscope slide looks like the simplest thing in the lab: a small strip of glass. But the type you pick affects what you can see and how safely you can handle it. Slides are used to look at cells and microorganisms and to keep specimens for later. This guide covers the main types of slide, their edges and corners, and how to prepare a specimen.

What Are Microscope Slides?

Microscope slides are thin, flat pieces of optical-quality glass or plastic that hold a specimen for viewing under a microscope. The most common size is 25.4 mm x 76.2 mm (1 x 3 inches), between 1 mm and 1.2 mm thick. Standard slides are flat and clear. Variations such as concave slides hold thicker samples or small volumes of liquid. Slides are also used to store, preserve and transport samples.

Types of Microscope Slides and Their Uses

1. Plain Slides The usual choice for most work. Plain slides are smooth and clear, and they suit wet mounts, where a liquid sample is covered with a cover slip.

2. Frosted Slides Frosted slides have a textured end you can write on, which makes labelling easy in a school or research lab. They come with a single or double frosted end.

3. Concave Slides Concave slides have a shallow well for thicker or liquid specimens. Water fleas and other water-bound organisms can move freely in the well without being damaged by a cover slip.

4. Prepared Slides Prepared slides come with the specimen already mounted, so there is nothing to prepare. We stock sets for botany, histology, zoology, bacteria and cell division.

Edges and Corners: Why They Matter

Edges and corners affect how safe a slide is to handle and which equipment it suits.

Edge Types:

  • Cut Edges: Cheaper, but they chip more easily and can cut fingers.
  • Ground Edges: Smoothed, so they are safer to handle and less likely to break.
  • Bevelled Edges: Ground at an angle rather than square. We stock these in plain and single frosted slides.

Corner Types:

  • 90-Degree Corners: The traditional square corner, and the sharper one to handle.
  • 45-Degree Corners: Now the usual choice. They are easier to handle and suit automated machines.
  • Clipped Corners: A slide with the corners taken off, without a precise angle.

How to Choose the Right Slide

Consider the Specimen:

  • For liquid samples: Plain or concave slides work best.
  • For thick or 3D specimens: Concave slides give the depth you need.

Think About the Application:

  • Need to label? Use frosted slides.
  • Doing staining work where the specimen has to stay put? Hydrophilic plain slides or charged slides hold it better.

Preparing Microscope Slides: Best Practices

Dry Mounts: Place the specimen directly on the slide, with a cover slip on top if you want one. Suitable for samples like pollen, feathers or hair.

Wet Mounts: Use a pipette to place a drop of liquid on the specimen, then lower the cover slip carefully to avoid air bubbles. Used for live organisms like paramecium.

Smears: Spread a thin layer of the specimen across the slide, let it air dry, and add a stain if necessary. Commonly used for blood or bacterial samples.

Section Mounts: Slice thin sections of a sample, such as plant tissue, and mount them on the slide. This shows internal structure in detail.

Advanced Options: Charged and Coated Slides

Charged slides, such as poly-L-lysine or silane-coated slides, keep specimens stuck to the glass during staining, fixing or retrieval. They are mostly used in pathology and advanced biology.

Why the Right Slide Matters

The slide you choose affects what you see. A hydrophilic plain slide lets liquid spread evenly, which gives a clearer image. A concave slide gives thicker specimens room to move. A frosted slide makes labelling quick in a busy lab.

Shop Microscope Slides

We stock plain, frosted, concave and prepared slides for students, teachers and labs. Browse our microscope slides, or go straight to the prepared slide sets.