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Aqueous Mounting Media’s for Fluorescent and Special Stains, Commercial Brutality?

We do a fair amount of special and fluorescent staining that requires aqueous mounting media and not the toluene based glue.  Normally for special stains I make up a glycerin jelly that has phenol and must be kept in the refrigerator.  This was taught to be the standard of aqueous cover slipping media.  It never dries, sticks to everything and smells terrible.

The fluorescent slides need something different, usually a special fluor mount bought at one of the large chemical companies.  This mount allows for very little light distortion while viewing through a con-focal or fluorescent scope.  The amount of light distortion is called refractive index.  Some of these mounting medias that having a low refractive index of 1.47 can be very expensive, $162.00 plus shipping for 10 ml.

Triple antibody using the confocal microscope.
Triple antibody using the con-focal microscope.

10 ml may be enough to cover slip 300 slides if using only 30 um per slide but that adds $.60 to the cost of every slide.  That may not seem like much but when it’s added to the total after processing, embedding, cutting, antibody plus working hours it can push the average researchers budget to the edge.

I thought, there has to be something better than this.  Large companies get most of their protocols from the old histology books and change 1 micro-gram and it becomes proprietary.  Then the price depends on demand and repeat customers (way too high).  This is what I call commercial brutality.

I’m way to enterprising to pay these prices and be happy about it.  Therefore I too will develop a protocol from the books and change one aspect of it and call it my own.  The difference is, I will formulate it, test it, have others test it, then make it available to all the labs I have daily contact with (10) and help them save money.

One way to stop this money merry go round is to limit profits from unbelievable pricing on medical products.  Paying $500.00 for a water bath that lasts 10 years is absurd!  $162.00 for 10 ml of mounting media is too much!

I have made 25 ml the histo-lo-gis-tics version of aqueous mounting media for about $20.00, but could be 100 ml for $40.00.  That’s the cost if you make it for yourself.  It’s a room temp, permanent media that will last for 2-3 years with anti fading agent and refractive index of 1.46.  So far it’s been tested by 2 independent labs in fluorescent microscopy and passed with no distortion.  2 more labs will be testing it this week and mine soon.

After testing is done, I will update the results, good or not good and post the recipe if it’s useful.

 

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Chemical Compatibility Guidlines

Chloroform
Wet Chemical chloroform

 

This is how I have started storing our stock of wet and dry chemicals.  Most labs have an abundance of both dry and wet chemicals that must be kept for reagent solutions, media mixes, pH calibration and other.  Depending on the size of the lab, chemicals might be stored inside of specially designed cabinets that are prevent accidental spills.  Sometimes the chemicals will be put on a shelf, countertop, refrigerator or freezer.  This is an issue in most of the clinical, research and academic laboratories I have worked in and may be for many others.  Over the years and out of want to be safe, I have designed a suitable solution for storing both wet and dry chemicals that is safe for everyone to use.

DSC02091

 

Chemicals can be hazardous if they leak, spill or come in contact with other non-compatible chemicals.  Therefore is it the duty of someone who cares to make sure this never happens.  For instance, I take chemicals very seriously, not because my mother was a chemist for so many years that she lost her sense of smell but because I was a victim of a small histology company and its lack of safety procedures.

The chemical storage protocol here has been modified from a hazardous waste guideline.  This guideline provides details of specific chemicals that can and cannot go together as a waste stream.  Therefore I conclude that these chemicals should also be stored in the same way.  There are some obvious conditions I would like to point out anyway.  Flammable cabinets should be used, not only for your sake, but for the firemen who might come to rescue you.  This tells everyone to beware.  This also goes for acid and base cabinets.  I feel these are necessary for the Modern laboratory.  Acids and bases do not go together, obviously. Secondary containers are helpful when space is limited and chemicals must be stored close together.  The container would contain a spill or leak from reaching other non-compatible chemicals.

Chemical incompatability
Chemical incompatibility

 

The chemical chart breaks down what chemical can and cannot be stored together, essentially making safety a top priority.  The PDF of the chart is below and will also be placed in the protocols page.

I hope this helps.

How do you store chemicals in your lab?

Chemical_Compatibility_Chart