FAQ’s: Glass Coverslips

Q1: What applications are Glass Coverslips best for?

MatTek’s high quality German Glass Coverslips provide the optimal thickness to use for high resolution microscopy techniques. In particular, when using a high Numerical Aperture (N.A.) MatTek Glass Coverslips are ideal for:

  • Confocal Microscopy Confocal Laser Scanning Microscopy (CLSM)
  • Fluorescence Microscopy
  • Green Fluorescence Protein (GFP)
  • Fluorescence Resonance Energy Transfer (FRET)
  • Immunofluoresence Microscopy
  • Phase Contrast Microscopy
  • Polarized Light Microscopy
  • Differential Interference Contrast (DIC)
  • Multi Photon Laser Scanning Microscopy (MPLSM)
  • High Resolution Image Analysis
  • Infrared Imaging
  • Calcium Imaging

… and MatTek Glass Coverslips (in particular, part #:  PCS-170-1818) have been used by customers for super-high resolution techniques such as:

  • Ground State Depletion with Imaging Microscopy (GSDIM)
  • direct stochastic optical reconstruction microscopy (dSTORM)
  • Photoactivated localization microscopy (PALM)
  • Total internal reflection (TIRF)
Q2: What coverslip thickness should I use? What do the various coverslip numbers correspond to?
Almost all objectives are optimized for a No. 1.5 coverslip thickness. Use of the No. 1.5 thickness gets increasingly important for higher numerical aperture coverslips (NA > 0.7). Use of other coverslip thicknesses can lead to optical distortion and loss of resolution. Therefore, for the vast majority of microscopy applications, the No. 1.5 coverslip thickness is optimal (Coverslip Part # PCS-1.5-xx.). The actual thickness of the glass coverslips depends on the Coverslip No./Part #, as follows:

Coverslip No.Part#Glass Thickness (mm)
Q3: Can MatTek Glass Coverslips be used for super-high resolution microscopy?
Yes! High tolerance MatTek Glass Coverslips (part # PCS-170-1818) are optimized for super-high resolution techniques such as GSDIM, dSTORM, PALM total internal reflection (TIRF), and confocal microscopy using high numerical aperture objectives.

Q4: What should I do if my cells won’t grow or if I want to improve growth on the coverslip?
Many cells will grow directly on MatTek uncoated coverslips. However, more difficult to grow cell types (e.g. neurons) will require coating with an extracellular matrix coating. Please contact Customer Service for assistance.

Q5: Why would one want to use gridded coverslips? What is the size of the grid? What if I can't see the grid?
The gridded coverslips allow one to refer to specific cells and follow them over time. For instance, individual cells can be microinjected, returned to the incubator, and observed at multiple time points since each cell can be identified with a unique alpha-numeric coordinate on the coverslip. MatTek’s gridded Glass Coverslips are available under part# PCS-1.5-1818-GRD.

Grid size: The grid consists of 520 unique alphanumeric squares. Each square measures 600 μm x 600 μm. The line thickness is 20 μm.

Visualization of the grid: The grid should be readily visible using a 10X brightfield objective. After you locate the cell of interest, switch to a higher magnification or fluorescence objective. However, the grid will not be visible using higher magnification or fluorescence objectives.

I can’t see the grid: A confluent monolayer of cells will typically mask the grid making it difficult or impossible to visualize. If you plan to visualize individual cells in a confluent monolayer, plate the cells on the side of the coverslip opposite the grid. To use this method, simply find a cell of interest and then focus down to underside of the coverslip to get the cell’s coordinates.

Q6: What are properties of the glass used to make the coverslips?
  1. Highest hydrolytic resistance (hydrolytic class 1).
  2. Excellent resistance to chemicals.
  3. Emission of alkali approximately 15 to 24 µg Na2O/g glass.
  4. Excellent properties for fluorescent microscopy.
  5. Incident ultraviolet rays with wavelengths longer than 320 nm do not cause fluorescence.
  6. Mercury lines at 334 and 365 nm do not create auto-fluorescence. (Note: For mercury illumination, filter out the mercury lines with wavelengths shorter than 313 nm to obtain best possible results.)
  7. Refractive index (@ 20°C): nD ** = 1.5230 tolerance ± 0.0015.
  8. Abbe number V = 55.
Q7: Do the coverslips come sterile?
No.   MatTek glass coverslips are shipped non-sterile and should be autoclaved prior to use.   After sterilization, place the coverslips into a sterile petri dish or multi-well plate, and plate your cells.