Almost As Good As the Expert Down the Hall: The Citations Database

database_1When you are faced with a new research challenge or are troubleshooting in the lab, nothing replaces the wisdom of the lab tech down the hall who has 20 years experience doing the very technique you need to try.

But, sometimes there isn’t a local expert handy.

The Citations Database on the Promega website provides another source of expertise for you. We curate peer-reviewed publications that cite the use of Promega products so that you can see what people have done and how they have done it. We include links to PubMed for articles that are in indexed journals, and we also include brief notes about how the Promega products were used in the research.

Whether you are working with a new sample type, troubleshooting nucleic acid isolation, or trying a completely new assay, see how the Citations Database can help you in the laboratory. Continue reading “Almost As Good As the Expert Down the Hall: The Citations Database”

Choosing Your Subcloning Strategy

Before you begin your subcloning, you need to know: The restriction enzyme (RE) sites available for subcloning in your parent vector multiple cloning region (or in the insert if you need to digest the insert); the RE sites available in the destination vector multiple cloning region (MCR); and if these same sites also occur in your insert. Once you know this information, you can use the chart below to decide which subcloning strategy to use.

4498MA-[Converted]

To learn more about subcloning, visit our Subcloning Notebook.

Top Ten Tips for Successful PCR

We decided to revisit a popular blog from our Promega Connections past for those of you in the amplification world. Enjoy:

magnesium-31

    • Modify reaction buffer composition to adjust pH and salt concentration.
    • Titrate the amount of DNA polymerase.
    • Add PCR enhancers such as BSA, betaine, DMSO, nonionic detergents, formamide or (NH4)2SO4.
    • Switch to hot-start PCR.
    • Optimize cycle number and cycling parameters, including denaturation and extension times.
    • Choose PCR primer sequences wisely.
    • Determine optimal DNA template quantity.
    • Clean up your DNA template to remove PCR inhibitors.
    • Determine the optimal annealing temperature of your PCR primer pair.

[Drum roll please]…and the  most important thing you can do to improve your PCR results is:

  • Titrate the magnesium concentration.

And if you want to, you can even build a custom PCR protocol using our iOS and Android device apps. Email it to your lab account, print it out for your notebook or just store it on your device for future reference.

The Price for Convenience May Not Be That Pricey After All

Hour glass

I was having a discussion with my mother just the other day about cleaning products (lively topic, I know). She showed me her newest time saver…prediluted bleach. Huh, I thought. I guess that does save a bit of time, but I couldn’t resist telling her that she was paying triple the price for a whole lot of water. She said, without pause, that it was worth it to her to not have to splash fully concentrated bleach around. A convenience worth paying for, in her words.

I don’t know why this struck me as odd. I pay for convenience all the time as I get older. When I started running gels back in college, I wouldn’t have dreamed of buying a precast gel, but several years into my lab life I found myself running more than 15 gels a week, so precast was really a convenient alternative. When I was a grad student, I poured all of my own plates (and most of the plates for older students, too!). Fast forward a few years, and I running upwards of 300 microbial selective cultures per week. The switch to prepoured plates was a no brainer.

When put in the context of what our time is worth, would you rather be thawing and mixing loading dyes, buffers, stains, reagents, etc., or are you better of grabbing a premixed, room-temp stable dye or ladder/loading dye mix off the shelf and getting on with your research? I think most scientists would agree that these small conveniences allow you to free up a little more time to do the important work you should be doing.

I’m curious…what time savers or convenience items do you find that make your day a little easier in the lab?

DNA Purification, Quantitation and Analysis Explained

WebinarsYesterday I listened in on the Webinar “Getting the Most Out of Your DNA Analysis from Purification to Downstream Assays”, presented by Eric Vincent–a Product Manager in the Promega Genomics group.

This is the webinar for you if you have ever wondered about the relative advantages and disadvantages of the many methods available for DNA purification, quantitation and analysis, or if you are comparing options for low- to high-throughput DNA purification. Eric presents a clear analyses of each of the steps in a basic DNA workflow: Purification, Quantitation, Quality Determination, and Downstream Analysis, providing key considerations and detailing the potential limitations of the methods commonly used at each step.

The DNA purification method chosen has an affect on the quality and integrity of the DNA isolated, and can therefore affect performance in downstream assays. Accuracy of quantitation also affects success, and the various downstream assays themselves (such as end-point PCR, qPCR, and sequencing) each have different sensitivities to factors such as DNA yield, quality, and integrity, and the presence of inhibitors. Continue reading “DNA Purification, Quantitation and Analysis Explained”