As histotechs, we are aware that slides are the star of the show. However, we also know that slides don’t work on their own. In the quiet corners of our labs, small equipment like slide dryers fade into the background, thanklessly performing their function. We cut slides, place them in the oven, set the timer, and forget about them until we hear the timer and remove our slides. Did you know that there are variables that can impact the effectiveness of slide dryers? 

Understanding these variables and making necessary adjustments can help to resolve issues with slides you may encounter in your lab. This small piece of equipment is an unsung hero that can improve workflow and increase efficiency in your lab. 

Picture these scenarios: 

• A rack of slides is placed in the slide dryer at 60°C for 30 minutes, but when removed the drying of each slide seems inconsistent. 
• A rack of slides is placed in the slide dryer set at 70°C for 15 minutes. Slides were removed from the dryer and stained for H&E only to find nuclear bubbling interfering with slide analysis. 
• A freshly dried slide is placed on the IHC stainer, 3 hours later it is complete, and slides are removed and coverslipped only to find that not all of the tissue adhered to the slide, making analysis inconclusive.

Let’s take a closer look at each of these and explore recommended slide dryer techniques to proactively address them.  
 
Inconsistent drying: This issue could happen if the slide dryer fails to maintain a steady temperature. If the dryer has a digital temperature control, consider placing a manual thermometer periodically  in the dryer to monitor consistency. Additionally, keep in mind that every time the door is opened, heat escapes and the dryer has to reestablish the desired temperature. Minimize opening the door by batching slides or even using multiple slide dryers for different applications.  
 
Slow and steady is the key to reduce overheating slides and nuclear bubbling: Slides should be dried at a constant temperature of 60-65°C for the most uniform drying. Turning up the heat to speed up drying is not ideal as this will turn the water into excess steam and can cause nuclear bubbling. 
 
Tissue Wash: This could be due to insufficient drying time, tissue type, or a combination of both factors. If this is happening with almost every slide, check the type of slide being used for the specific application. If already using a reliable adhesion slide, consider increasing the drying time. Use caution if the heat is already within the range 60-65° C, exceeding this could overheat the specimen or cause nuclear bubbling. More challenging tissues like skin, bone, or fatty tissues may need a longer drying time than others.  
 
Looking for an easy way to ensure consistent, rapid, and efficient drying times? Check out the StatLab High Capacity Slide Dryer designed to give maximum drying capacity by circulating air through the base of the instrument to reduce drying times by up to 75%!