How to treat fertilizer burned grass spots

Many of us have dry spots in our lawns that we just cannot seem to get anything to grow there. In my case this is because I put too much fertilizer in one area and it burned away the vegetation. So this summer I decided to figure out a way to get new grass seed to grow there.

I started my research by reading various articles online to get a better understanding of how long it takes for the fertilizer I laid last year to dilute to a level that will allow new grass to grow. Of course, I don’t want to pay for a laboratory soil test so I’m testing more conventional ways. Most of the articles tell you to remove the fertilizer (which in my case is too late since the grass is already burned), water a lot to wash the fertilizer away, and then wait and see. I’m not very patient and I have a feeling that the only part of this that might work is the water.fertilizer burned grass

I decided to use gypsum which binds with the salts in the soil. It is often used to tread fertilizer burned yards and since my landscaping ideas last year lead me to burn my grass I thought this would be the best option. Of course, it is recommended to have a soil test done by a laboratory before applying gypsum since it does change the chemical makeup of the soil by adding calcium.

After I applied the gypsum I used plenty of water over the next couple of weeks to make sure it washed into the soil.

After about 2 weeks I took a garden rake and raked the burned spots to loosen up the dirt.  I then scraped of the top layer of soil over the dry spots to remove the old, dead grass and bad soil.  I decided it would probably be best to add a little fresh soil I bought in a bag before replanting.  After applying the soil I replanted fresh seed and covered with a little hay to help keep it from blowing and washing away.  Then I applied more water over the course of about 2 weeks.

In my case, this worked great and I now have new grass growing in the spots that I burned with fertilizer last summer.

Posted in Chemicals, Safety

How to choose the right hot plate magnetic stirrer for your lab.

Often times scientists need to stir or heat solutions. Sometimes they need to to both at the same time.  This can be accomplished by using a hot plate magnetic stirrer found in a laboratory.  There are three different varieties ranging from a single alone hotplate which only heats, a magnetic stirrer which uses a stirring rob to mix solution, or a hot plate magnetic stirrer with provides both functions in one unit.

hotplate-magnetic-stirrerAll three units come with a ceramic top plate that is chemical resistant and you can choose from a standard model that has knobs to control the stirring speed and heat or a newer digital hotplate, stirrer or hotplate stirrer combo.  The digital model does not require a temperature probe since it is displayed on the LED screen. Additionally, the end user has the option of choosing from a US plug or European Plug.

While it’s best (and safest) to purchase a quality machine from a laboratory supplier, these items can be costly and some scientists have resorted to building their own.  To accomplish this they take apart a hotplate and install an electrical motor that spins.  They attach a positive magnet to the the motor and use a negatively charged magnet in the solution to stir the solution.  Typically the electrical motor has a separate AC plug. There are a number of videos that show you how to do this on YouTube like this one:

Most hotplate stirrers are priced between $200 and $400 and very depending on the quality and functionality you choose. Good places to buy lab equipment for heating and stirring vessels is online or through your laboratory products supplier.  Most products suppliers offer a variety of lab equipment with their other consumable products. If you ask for a price quote you might be able to get a better deal and save some money on your purchase.


Posted in Uncategorized

The laboratory chemical safety guide

The laboratory safety guide is meant to be a resource for scientists and lab technicians that come into contact with hazardous chemicals and solutions as well as a guide for general lab safety.  Today we’re going to discuss hazardous chemical warnings, chemical and environmental safety, and chemical storage.

chemical-safetyMany of the packages and supplies that are used in a laboratory are chemicals. It’s important to understand how dangerous the chemical is that you are working with and what to do if you come into contact with it. The chemical you are working with, if hazardous, will have a hazard marking on the label.  This marking will vary depending on the type of chemical and typically indicate if the chemical is flammable, combustable, organic peroxide, explosive, water reactive, unstable, or compressed gas to name a few.  It’s important to read the safety instructions for working with each chemical and understand the warning signs.  This will prevent mistakes and dangerous reactions.

It’s also important to know how to store your chemicals.  Generally you will need to store them in a lockable, flame proof cabinet. Even some paints and wood stains have to be kept in these types of cabinets.  This will contain a fire if the chemicals should somehow ignite. You can find chemical storage at cabinets at laboratory supply stores, hardware stores and online retailers.

Disposing of your chemicals is something that if often overlooked.  Many chemicals should not be washed down the drain or even mixed with water.  Proper disposal is imperative to the safety of the handler(s).  If you’re going to dispose of a chemical you should review the guidelines at the EPA.

For more information on chemical safety and disposal visit:

Tagged with: , ,
Posted in Chemicals, Lab Supplies, Safety

Choosing the right laboratory gloves

When working in the laboratory it’s important to alway where protective gloves.  This will not only help from cross-contamination but also protect the scientist from coming in contact with dangerous chemicals and solutions. While there are many options and brands to choose from, you want to make sure that you pick the glove that has the features you desire. nitrile-lab-gloves

Most laboratory gloves are made from either nitrile or latex rubber and manufactured in various thicknesses.  They are available in sizes: extra small, small, medium, large and extra large. Some gloves are lined with aloe to help keep your hands moist and soft since many scientists are wearing them all day.  Other latex and nitrile gloves feature a textured finger grip to prevent spillage of slippery vessels.

While it may seem like a simple choice,  you will be surprised at how particular a person can come to a single brand. Most people like to stick with what they are used to and do not give other brands a chance, however,  this is not wise as one can typically find better pricing and even quality by shopping around.

In the U.S., many laboratories that are affiliated with universities, government, or large private institutions buy their laboratory supplies from two main companies… Thermo Fisher Scientific and VWR International. This is because these companies generally have the state or university contract meaning they offer some sort of discount structure to their contracted accounts.  These companies are distributors and therefore buy from wholesalers or manufacturers and re-sell these items to their customers with a hefty mark-up.  The thing that many scientists do now realize is that they can actually buy most of their products at better prices directly from manufacturing companies and gloves are no exception.  Often gloves can be bought direct for much less than through a distributor.

If you are considering ordering laboratory gloves then you ought to shop around and ask for price quotes and samples before making your final decision.  Depending on your labs usage you just might save a bundle of that grant funding.

For more information on lab safety training view this guide by Princeton University


Tagged with:
Posted in Lab Supplies

How to use a single channel micropipette

A pipetted is a device used to draw a vacuum on a pipette.  The types of pipettes that are used are typically in 3 forms but all work on the same concept. There is the glass or plastic serological pipette used with a controller (although I have seen scientists use their mouths to draw the fluid…not recommended), plastic pipet tips for a single or multichannel volumetric instrument, or bulbs.

With the various types of controllers out there we are only going to talk about two in this article.  The first type is a gunsingle-channel-micro-pipette shaped controller for serological pipettes. The other is a micropipette for plastic cone tips.

The gun controller works by pulling a suction trigger and a release trigger to activate the instrument.  This is done with your fingers.

The single channel (micro) pipette is controlled with your thumb and is shaped much like the tip itself. As you press and release the air is expelled and draw back in.

Micropipettes are devices that are used to deliver small volumes of liquid.  Usually in the range of 0.2 to 1000 micro liters. And like other forms of laboratory instrumentation, the micropipette must be operated with precision so that your measurements can be reproduced consistently.

Here are instructions on how to use a micropipette

The first step is to set the micropipette to the correct volume you want to transfer.  The instrument requires a disposablehow-to-pipette tip. Tips are typically stored in plastic racks that are autoclaveable.  Use gloves when working with pipet tips to eliminate contamination.

Attache a tip by pressing the pipette firmly down on the tip.  Then turn the adjusting knob on to your desired volume.

Next take your sample solution and use the micropipette to transfer your sample to another tube or vessel.

Press the plunger to the first stop and insert the tip into the liquid.  A good rule of thumb is to insert half the tip into the solution. Allow the plunger to slowly return to its un-depressed position as the solution is drawn into the tip, pause for a second and then pull the pipette straight up

Place the tip all the way into the first tube. Press the plunger until it stops and all of the solution is expelled. With the plunger still pressed.  Slowly remove the tip from the solution. Now you can eject the tip and get a new one.  Continue this process until you’ve finished.

Tagged with: , , , , ,
Posted in Instruments, PCR, Pipetting, Tissue Culture

5 Cell Culture Products Your Lab Needs

When culturing cells in the laboratory there are a number of products you will need to grow your cell colonies in a consistent and controlled environment.  While there are a number of products you will need, below is a list of our top 5 most used cell culture products. z

Cell culture flasks

Culture flasks are used to grow cultures in a controlled environment. Mostly sold in 3 sizes, T25, T75 and T175, they are available with vented or plugged caps.  As suggested, the vented caps have small cut out vents with an inserted filter. This allows airflow while keeping contaminates out. The other option is a plugged cap cell culture flask.  These are completely sealed caps and allow no airflow.

Cell culture flasks are treated with tissue culture binding solutions to encourage growth.  The are made form polystyrene plastic with molded graduations.

Cell culture platescell-culture-supplies

Cell culture plates are rectangular plastic plates that have small wells to separate cell colonies. They are available in 6, 12, 24,48 and 96 well options. The plates are the same size but the well sizes vary to accommodate more or less wells while efficiently using the space provided. Generally these plates are sold with lids and packaged together.  These plates are also made from polystyrene plastic and tissue culture treated.  They should always come certified sterile.

Laboratory shaker

An orbital shaker is used to mix solution in places, flasks, dishes and other vessels.  There are all kinds of shakers available including ones for CO2 incubators and shakers that offer their own incubation enclosure.  Orbital shakers can also accommodate other laboratory vessels including tubes.  Additionally, you can add accessories such as platforms and clamps and some are designed specifically for plates, tubes and flasks.

Learn more about cell culture:

Serological pipette

Serological pipettes are used with pipette controllers.  These control the volume of solution drawn and expelled from the pipette.  These pipettes are sold in sizes ranging from 1mL all the way to 50mL sizes.  Serological pipettes are available in glass or polystyrene plastic. They feature graduation marks and should have a filter plug in the end that inserts into the controller.  This prevents solution from accidentally getting drawn into the controlling instrument.

The best serological feature a stretched design at the point.  This means the pipette is all one piece and allows for a smooth ejection without any build up.  The other option is welded tip cone onto a pipette cylinder.

Cell culture dishes

Much like petri dishes, cell culture dishes are circular plastic plates with fitting lids and a tissue culture growing surface.  They come in sizes ranging from 30mm to 150mm diameter.  While the most popular size is by far the 100 x 20mm dish, your research may require a different sized growing area.

Tagged with: , , , , , , , , ,
Posted in Lab Equipment, Lab Supplies, Tissue Culture