Posts by Rachel Kohn
CDC Refrigeration Guidelines for Submitting COVID-19 Specimens for Testing
While the search for a Coronavirus vaccine proceeds at full throttle a crucial issue is proper collection, labeling, storage and shipping of COVID-19 specimens to CDC laboratories for testing. Among procedures spelled out in the CDC’s Interim Guidelines is that coronavirus specimen shipments must be stored at 2-8⁰C and shipped overnight on icepack for testing within 72 hours. If a delay in shipping is expected, specimens must be stored at -70⁰C or lower. These agree with a companion guideline for post-mortem testing.
Temperature Guidelines for COVID-19 Test Kits
Because there are so many sites collecting specimens there is a national shortage of reagents for the tests. Test kits are available for real-time PCR and in vitro diagnostic procedures. One manufacturer specifies storage temperatures from -10⁰ to -30⁰C down to ≤-70⁰C depending on the components of the kits.
To meet these storage requirements you should be familiar with
- Scientific Refrigerators
- Scientific Freezers
How a HPLC Digital Flow Meter Works
Before explaining how a HPLC digital flow meter works here’s an explanation of what digital flow meters do:
Digital flowmeters performing high performance liquid chromatography are used to measure the accuracy of HPLC pumping systems in order to meet FDA and other regulations regarding installation qualification (IQ), operational qualification (OQ) and performance qualification (PQ) of equipment used in the pharmaceutical and biopharmaceutical industries as well as other analytical labs.
The process demands accurate, reproducible column retention time as an analyte (what is being analyzed) is pumped through the HPLC system.
These precision digital flow meters are not to be likened to flow meters used on process lines measuring flow rates in, for example, thousands of gallons per minute but instead in fractions of milliliters per minute. … Read the rest
How to Specify a Compact Medical Refrigerator
Health care clinics must exercise care when selecting a compact medical refrigerator to store temperature-sensitive products such as vaccines and other pharmaceuticals. A compact medical refrigerator is a smart choice when space is at a premium, but a small size should not be at the cost of critical features that protect contents. This post provides tips on how to specify a compact medical refrigerator.
Why a Medical Refrigerator is Important
If there is temptation to buy a dormitory or residential-grade refrigerator it must be resisted. In fact, the former is definitely ruled against in the CDC’s Vaccine Storage and Handling Toolkit while the latter may be acceptable under certain conditions. We encourage you to download and review these guidelines, updated for 2020 before you decide on your medical refrigerator.
Especially important is compliance with CDC and Vaccines for Children refrigeration guidelines if your healthcare facility participates in these programs.
The “Cost”
… Read the restHow to Degas Liquids with Ultrasonic Energy
Degassing liquids of various viscosities is undertaken across a broad spectrum of industries and for a variety of reasons. Before describing how ultrasonic energy achieves fast, efficient degassing we provide you with a few definitions.
Degassing Defined
Degassing, as the name suggests, is removing trapped air (deaeration) or other gases from liquids. Most if not all liquids contain trapped air. You can see that by allowing a glass of water to remain on the countertop for a period of time. Bubbles will form on the walls of the glass.
A more vivid demonstration is opening a bottle of seltzer, carbonated beverage, champagne or beer. Bubbles fizz immediately after the pressure in the container is reduced. In this case the gas being removed is carbon dioxide rather than air.
But degassing is also necessary to remove trapped air from oils, adhesives and paint among other products where the air can interfere … Read the rest
How to Select an Under Counter Lab Freezer
If space is at a premium for safely storing temperature-sensitive pharmaceuticals, lab samples or costly biological specimens, an under counter lab freezer may be the answer. Laboratory freezers are more sophisticated than residential or commercial units. They have features essential to protect contents from temperature excursions. This post provides researchers with useful information to help with their selection process.
What to consider when selecting under counter lab freezers
First, let’s put the dollar sign in perspective. These units will cost more than residential or commercial units. You (and your accounting department) must compare the cost of the lab freezer to the value of its contents.Proper storage temperatures for many pharmaceuticals, specimens and biological samples are defined. Temperature excursions above or below these may result in losses that in some cases may be irreplaceable.The cost of loss due to freezer malfunction is described in the article Cost of Research Lab Freezer … Read the rest
Moisture Balance Ideal for QC in Molding Plastics
Operators of extrusion molding, injection molding, thermoforming and related equipment must pay particular attention to resin moisture content because too much or too little moisture will impact the quality of molded products. Correct moisture content depends on the resins being used and is specified by plastic resin manufacturers.
Resin manufacturers may ship product at the correct moisture content but equipment operators should take steps to ensure ambient conditions at the plant do not raise or lower the content prior to processing. Two important steps in quality control are proper resin storage and using commercial drying ovens. Periodic checks with a benchtop moisture analyzer programmed for plastic resins provide assurances that moisture content is on target, or otherwise call for pre-processing adjustments.
The Benchtop DSC 71P Lab Moisture Analyzer for Quality Control
Operating on the LOD (loss of weight on drying) process it handles samples to 71 grams and delivers … Read the rest
Selection Tips for Moisture Analyzers
If you are shopping for a moisture analyzer and feel stymied by the number of choices, these moisture analyzer selection tips should help.
Moisture balance selection criteria are based on factors including:
- Resolution or the smallest difference that can be read on the display. This is also termed readability or readout.
- Repeatability – the ability of a moisture balance to display the same result when the same sample is tested repeatedly. Expressed as a standard deviation.
- Features important to performing moisture analysis. These are based on the characteristics of product being analyzed such as those require special heating profiles.
- Specialized capabilities such as testing products with extremely low moisture content specs, providing graphic displays of changing moisture content, and building libraries of frequently performed tests.
Four Candidate Moisture Analyzers
Tovatech offers several models of moisture analyzers from which researchers or QC personnel can select the most cost-effective solution to their … Read the rest
Manual or Auto-Defrost Cold Storage Units for Lab
Lab refrigerators and lab freezers come in various sizes and temperature capabilities, many of which are designed for specific storage functions. What you store in these units has a large part in determining the type of unit you purchase. This post will cover decision-making factors such as storage temperature capability and whether manual or auto-defrost equipment should be specified when you choose manual or auto-defrost cold storage units for the lab.
We’ll separately take a look at scientific refrigerators and scientific freezers, then provide suggestions on how to manage defrosting operations.
Always keep in mind that temperature monitoring and alarming is a subject onto itself in laboratory refrigerators and freezers. The defrosting operation by definition signals a change in storage temperature within these units, whether a scientific freezer or scientific refrigerator. We’ll touch on this briefly at the end of our post.
In addition, two important points to include in … Read the rest
Choosing a Moisture Analyzer for Sludge Dewatering Operations
Moisture content is a critical criterion to determine the acceptability of treated sewage sludge (called biosolids or sludge cake) as an acceptable product for use as a fuel and a nutrient-rich organic material. Moisture analyzers play a vital role in quality control procedures at sludge dewatering plants.
After the brief intro our post explains two options for moisture analysis at these plants.
A Brief Intro to Sludge Dewatering at Sewage Treatment Plants
Improved wastewater treatment processes separate sewage sludge, called cake, as a usable biomass from water that must meet regulated levels of purity before being discharged into water courses.
For the cake to be useable its moisture content must be known to within 0.5 – 1%. This knowledge helps operators to control the drying process that turns biomass into a fuel. Industrial-scale dryers are used in this operation. As you might imagine, the lower the moisture content the more … Read the rest
Moisture Analyzer for Plastic Resins
When you select a moisture analyzer for low-moisture plastic resins you will need a model that that not only can quickly but also accurately gauge the moisture content of these resins. And as with many quality control requirements that involve moisture content, you’ll want a moisture balance that can meet standards set by trade associations and professional organizations.
In this post you’ll get a briefing on the following:
- why low moisture content is important in plastic resins
- a technical standard that applies to determining moisture in plastics
- how benchtop moisture analyzers work
- a standards-compliant moisture analyzer
for plastic resins
Why Low Moisture Content is Important
Owners of injection molding companies and operators of injection molding machines are aware that incorrect moisture content in plastic resins can result in an inferior finished product.
Product shipped from resin suppliers may have the specified moisture content but ambient conditions … Read the rest