An Introduction to Lyophilization: Process, Benefits & Possibilities

Amber glass bottle filled with lyophilized beads sitting on a lab bench.

Lyophilization is a process designed to remove water from a sample or product through a controlled freezing and vacuum application. The method leverages the triple point of water, where solid, liquid, and gas phases coexist under specific temperature and pressure conditions. The result is a room temperature stable product that is much lighter than the original sample or product.

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Promega qPCR Grant Series #3: Immunotherapy Researcher, Dr. Sabrina Alves dos Reis 

Professional headshot image of Dr. Sabrina Alves dos Reis, subject of the blog post
Sabrina Alves dos Reis

In our third and final installment of the Promega qPCR Grant Recipient blog series, we highlight Dr. Sabrina Alves dos Reis, a trained immunotherapy researcher. Her work has focused on developing tools for more accessible cancer therapies using CAR-T cells. Here, we explore Dr. Alves dos Reis’ academic and scientific journeys, highlight influential mentorship and foreshadow her plans for the Promega qPCR grant funds. 

Dr. Alves dos Reis’ career began with a strong affinity for biology. As an undergraduate student, she pursued a degree in biological science, where she developed a foundational understanding for designing and developing research projects. As her passion for science heightened, she decided to continue her journey in science, culminating in a PhD at the Fundação Oswaldo Cruz Institute in Rio de Janeiro, Brazil. Her research projects focused on the unexplored territory of adipose tissue as a site for Mycobacterium leprae—or leprosy bacillus—infection. She mentioned that this work piqued her curiosity for improving immunotherapies and laid the foundation for her future in cancer research.  

Continue reading “Promega qPCR Grant Series #3: Immunotherapy Researcher, Dr. Sabrina Alves dos Reis “

Promega qPCR Grant Series #2: Molecular Biologist, Laura Leighton

Our second installment of the Promega qPCR Grant Recipient blog series highlights Dr. Laura Leighton, a trained molecular biologist and postdoctoral researcher at the Australian Institute for Bioengineering and Nanotechnology. Leighton’s scientific journey features a passion for molecular biology and problem-solving. Her path has been illuminated by mentorship, relationships with fellow scientists and a commitment to creativity in overcoming challenges. Here, we explore her scientific journey, reflect on research lessons and foreshadow her plans for the Promega qPCR grant funds.

Dr. Laura Leighton grew up in a rural area in Far North Queensland, Australia, where she spent her early life exploring critters on the family farm. Her upbringing was infused with a deep connection to the environment, from raising tadpoles in wading pools to observing wildlife and witnessing food grow firsthand. Observing the biology around her ultimately piqued her interest in science from a young age. She then began her academic journey in 2011 at the University of Queensland, Australia. She studied biology while participating in a program for future researchers, which led her to undergraduate research work in several research labs.  She dabbled in many research avenues in order to narrow in on her scientific interests all while adding different research tools to her repertoire.

After serving as a research assistant in Dr. Timothy Bredy’s lab, she decided to continue work in this lab and pursue a PhD in molecular biology. During her PhD, Leighton worked on several projects from cephalopod mRNA interference to neurological wiring in mice. The common thread in these projects is Leighton’s passion for the puzzles of molecular biology:

“I also love molecular engineering and the modularity of molecular parts. There’s something really special about stringing together sequence in a DNA editor, then seeing it come to life in a cell,” she says.

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Promega qPCR Grant Series #1: Marine Plant Ecologist, Dr. Agustín Moreira-Saporiti

Dr. Agustín Moreira-Saporiti is a postdoctoral researcher at the Marine Biological Laboratory and is studying flowering processes in marine seagrass

Marine seagrasses are submerged flowering plants that form essential underwater meadows, fostering diverse ecosystems and providing a habitat for marine life. Our first Promega qPCR Grant winner and marine ecologist, Dr. Agustín Moreira-Saporiti, plans to continue adding to a fascinating body of work aimed at understanding flowering in marine seagrasses.

Dr. Moreira-Saporiti began his journey into marine plant ecology at the University of Vigo, Spain, where he earned a bachelor’s degree in marine sciences. He then went on to complete a master’s degree at the University of Bremen (Germany) where his thesis focused the ecology of seagrasses in Zanzibar, Tanzania. His passion for marine botany led him down a deeper exploration of marine plants, unraveling the intricate web of ecosystem processes within seagrasses.

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No Horsin’ around with Halal Meat Authentication


Today’s blog is written by guest blogger, Sameer Moorji, Director, Applied Markets.  

People’s diets are frequently influenced by a wide range of variables; with environment, socioeconomic status, religion, and culture being a few of the key influencers. The Muslim community serves as one illustration of how culture and religion can hold influence over people’s eating habits.

Halal meat on cutting board

Muslims, who adhere to Islamic teachings derived from the Qur’an, frequently base dietary choices on a food’s halal status, whether it is permissible to consume, or haram status, forbidden to consume. With the population of Muslims expected to expand from 1.6 billion in 2010 to 2.2 billion by 2030, the demand for halal products is anticipated to surge (2).

By 2030, the global halal meat market is projected to reach over $300 billion dollars, with Asia-Pacific and the Middle East regions being the largest consumers and producers of halal meat products (3). Furthermore, increasing awareness and popularity of halal meat among non-Muslim consumers, as well as strengthening preference for ethical and high-quality meat, are all contributing to demand.  

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Have No Fear, qPCR Is Here: How qPCR can help identify food contamination

Foodborne disease affects almost 1 in 10 people around the world annually, and continuously presents a serious public health issue (9).

Food Contamination-Strawberries-Blueberries-Magnifying glass
Food Contamination is common and can be seen in a variety of forms and food products.

More than 200 diseases have evolved from consuming food contaminated by bacteria, viruses, parasites, and chemical substances, resulting in extensive increases in global disease and mortality rates (9). With this, foodborne pathogens cause a major strain on health-care systems; as these diseases induce a variety of different illnesses characterized by a multitude of symptoms including gastrointestinal, neurological, gynecological, and immunological (9,2).

But why is food contamination increasing?

New challenges, in addition to established food contamination hazards, only serve to compound and increase food contamination risks. Food is vulnerable to contamination at any point between farm and table—during production, processing, delivery, or preparation. Here are a few possible causes of contamination at each point in the chain (2):

  • Production: Infected animal biproducts, acquired toxins from predation and consumption of other sick animals, or pollutants of water, soil, and/or air.
  • Processing: Contaminated water for cleaning or ice. Germs on animals or on the production line.
  • Delivery: Bacterial growth due to uncontrolled temperatures or unclean mode of transport.
  • Preparation: Raw food contamination, cross-contamination, unclean work environments, or sick people near food.

Further emerging challenges include, more complex food movement, a consequence of changes in production and supply of imported food and international trade. This generates more contamination opportunities and transports infected products to other countries and consumers. Conjointly, changes in consumer preferences, and emerging bacteria, toxins, and antimicrobial resistance evolve, and are constantly changing the game for food contamination (1,9).

Hence, versatile tests that can identify foodborne illnesses in a rapid, versatile, and reliable way, are top priority.

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qPCR: The Very Basics

Real-Time (or quantitative, qPCR) monitors PCR amplification as it happens and allows you to measure starting material in your reaction.
qPCR monitors amplification in real and allows you to measure starting material.

For those of us well versed in traditional, end-point PCR, wrapping our minds and methods around real-time or quantitative (qPCR) can be challenging. Here at Promega Connections, we are beginning a series of blogs designed to explain how qPCR works, things to consider when setting up and performing qPCR experiments, and what to look for in your results.

First, to get our bearings, let’s contrast traditional end-point PCR with qPCR.

End-Point PCRqPCR
Visualizes by agarose gel the amplified product AFTER it is produced (the end-point)Visualizes amplification as it happens (in real time) via a detection instrument
Does not precisely measure the starting DNA or RNAMeasures how many copies of DNA or RNA you started with (quantitative = qPCR)
Less expensive; no special instruments requiredMore expensive; requires special instrumentation
Basic molecular biology techniqueRequires slightly more technical prowess

Quantitative PCR (qPCR) can be used to answer the same experimental questions as traditional end-point PCR: Detecting polymorphisms in DNA, amplifying low-abundance sequences for cloning or analysis, pathogen detection and others. However, the ability to observe amplification in real-time and detect the number of copies in the starting material can quantitate gene expression, measure DNA damage, and quantitate viral load in a sample and other applications.

Anytime that you are performing a reaction where something is copied over and over in an exponential fashion, contaminants are just as likely to be copied as the desired input. Quantitative PCR is subject to the same contamination concerns as end-point PCR, but those concerns are magnified because the technique is so sensitive. Avoiding contamination is paramount for generating qPCR results that you can trust.

  1. Use aerosol-resistant pipette tips, and have designated pipettors and tips for pre- and post-amplification steps.
  2. Wear gloves and change them frequently.
  3. Have designated areas for pre- and post-amplification work.
  4. Use reaction “master mixes” to minimize variability. A master mix is a ready-to-use mixture of your reaction components (excluding primers and sample) that you create for multiple reactions. Because you are pipetting larger volumes to make the reaction master mix, and all of your reactions are getting their components from the same master mix, you are reducing variability from reaction to reaction.
  5. Dispense your primers into aliquots to minimize freeze-thaw cycles and the opportunity to introduce contaminants into a primer stock.

These are very basic tips that are common to both end-point and qPCR, but if you get these right, you are off to a good start no matter what your experimental goals are.

If you are looking for more information regarding qPCR, watch this supplementary video below.


We’re committed to supporting scientists who are using molecular biology to make a difference. Learn more about our qPCR Grant program.  


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Optimizing PCR: One Scientist’s Not So Fond Memories

primer_tubesThe first time I performed PCR was in 1992. I was finishing my Bachelors in Genetics and had an independent study project in a population genetics laboratory. My task was to try using a new technique, RAPD PCR, to distinguish clonal populations of the sea anemone, Metridium senile. These creatures can reproduce both sexually and asexually, which can make population genetics studies challenging. My professor was looking for a relatively simple method to identify individuals who were genetically identical (i.e., potential clones).

PCR was still in its infancy. No one in my lab had ever tried it before, and the department had one thermal cycler, which was located in a building across the street. We had a paper describing RAPD PCR for population work, so we ordered primers and Taq DNA polymerase and set about grinding up bits of frozen sea anemone to isolate the DNA. [The grinding process had to be done using a mortar and pestle seated in a bath of liquid nitrogen because the tissue had to remain frozen. If it thawed it became a disgusting mass of goo that was useless—but that is a topic for a different blog.] Since I had never done any of the procedures before, my professor and I assembled the first set of reactions together. When we ran our results on a gel, we had all sorts of bands—just what he was hoping to see. Unfortunately, we realized that we had added 10X more Taq DNA polymerase than we should have used. I repeated the amplification with the correct amount of Taq polymerase, and I saw nothing. Continue reading “Optimizing PCR: One Scientist’s Not So Fond Memories”

A Quick Method for A Tailing PCR Products

PCR experiment and products, pipette tip, tube in researcher's hand.
PCR is a common technique used in research labs to amplify DNA.

Some thermostable DNA polymerases, including Taq, add a single nucleotide base extension to the 3′ end of amplified DNA fragments. These polymerases usually add an adenine, leaving an “A” overhang. There are several approaches to overcome the cloning difficulties presented by the presence of A overhangs on PCR products. One method involves treating the product with Klenow to create a blunt-ended fragment for subcloning. Another choice is to add restriction sites to the ends of your PCR fragments. You can do this by incorporating the desired restriction sites into the PCR primers. After amplification, the PCR product is digested and subcloned into the cloning vector. Take care when using this method, as not all restriction enzymes efficiently cleave at the ends of DNA fragments, and you may not be able to use every restriction enzyme you desire. There is some useful information about cutting with restriction sites close to the end of linear fragments in the Restriction Enzyme Resource Guide. Also, some restriction enzymes require extra bases outside the recognition site, adding further expense to the PCR primers as well as risk of priming to unrelated sequences in the genome.

Continue reading “A Quick Method for A Tailing PCR Products”

How Do I Choose the Right GoTaq® Product to Suit My Needs for EndPoint PCR?

We offer a wide array of GoTaq® DNA Polymerases, Buffers and Master Mixes, so we frequently answer questions about which product would best suit a researcher’s needs. On the Taq Polymerase Page, you can filter the products by clicking the categories on the left hand side of the page to narrow down your search. Here are some guidelines to help you select the match that will best suit your PCR application. Continue reading “How Do I Choose the Right GoTaq® Product to Suit My Needs for EndPoint PCR?”