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Multiplexing Bio-Plex Pro Diabetes and Cytokine Assays

 :: Posted by American Biotechnologist on 07-01-2010

In a previous post we introduced Bio-Rad’s Bio-Plex Pro Diabetes and Cytokine assays and mentioned how one of the biggest advantages that the kit offers to researchers is the ability to multiplex cytokine and diabetes biomarkers in one tube. In the attached tech note: Multiplexing Compatibility of the Bio-Plex Pro Diabetes and Cytokine Assays: Human and Mouse Panels, Zimmerman et al. demonstrate the compatibility of 40 human cytokine assays with all 10 human diabetes assays and 32 mouse cytokine assays with all 8 mouse diabetes assays. The data includes an analysis of sensitivity, specificity and accuracy with limits of detection as low as 0.1pg/ml for several cytokine and diabetes biomarkers.

Multiplexing Compatibility of the Bio-Plex Pro Diabetes and Cytokine Assays: Human and Mouse Panels

Simplifying Gene Knockdown Experiments

 :: Posted by American Biotechnologist on 05-17-2010

If you’ve ever done gene knockdown experiments, you know that the process can be complicated and involve many steps. siRNA design, cell culture, perfect cell confluency, transfection or electroporation, downstream analysis etc. Bio-Rad now has a plethora of instruments and reagents to help you simplify the process. In a recently published article in the Journal of Visualized Experiments, scientists demonstrated a pathway study that makes use of Bio-Rad’s many strengths in the area of cell culture and gene silencing including streamlining cell counting with the TC10 automated cell counter, electroporating multiple samples simultaneously using the MXCell electroporation system and simultaneously assessing RNA quality and quantity with the Experion automated electrophoresis system.

If you want to learn about more ways to simplify your siRNA experiments checkout:

McCoy, A., Litterst, C., Collins, M., & Ugozzoli, L. (2010). Using an Automated Cell Counter to Simplify Gene Expression Studies: siRNA Knockdown of IL-4 Dependent Gene Expression in Namalwa Cells Journal of Visualized Experiments (38) DOI: 10.3791/1904

How to Enrich Low Abundance Proteins from Tissues, Cell Lines and Bacteria

 :: Posted by American Biotechnologist on 05-06-2010

Biotechnologists engaged in protein biomarker studies are well aware of some of the challenges they face trying to identify biomarkers in albumin and IgG rich serum and plasma. Protein biomarkers generally tend to be low-abundance proteins which are very difficult to detect among highly complex samples. Furthermore, an ever-increasing amount of biomarker studies are focused on identifying biomarkers in other biological sources such as muscle tissue and cell lines. Traditional approaches to solving this problem include depletion methods for removing high abundant proteins so that the proverbial “needle in the haystack” biomarker is easier to locate. While this approach has its advantages, it suffers from being too specific and may not work well in sample types other than serum and plasma.

Bio-Rad Laboratories Inc. has developed the ProteoMiner protein enrichment technology which uses a library of hexapeptides to bind all proteins in a complex mixture allowing reduction of high-abundance proteins and enrichment of medium and low-abundance proteins.

This Tech Note discusses the use of ProteoMner protein enrichment kits for the enrichment of low- and medium- abundance proteins and the depletion of high-abundance proteins in tissue, cell line and bacterial samples, with detailed experimental parameters in a 2-D gel based proteomics workflow.

Enrichment of Medium- and Low-abundance Proteins

How to Perform Highly Efficient Reverse siRNA Transfection

 :: Posted by American Biotechnologist on 05-03-2010

Short interfering RNAs (siRNAs) are powerful tools to suppress gene expression in mamalian cells. While siRNA transfection can often be bogged down by cell seeding and density the highlited study demonstrates a highly efficient reverse siRNA transfection protocol for A549 cells using Bio-Rad’s siLentFect lipid reagent that does not require prior seeding of cells. Furtheromore, the simplicity of the protocol makes it suitable for high-throughput transfection. The authors acheived an average of 94% knockdown for the two genes that were targetted without impairing cell viability.

<highly efficient reverse siRNA transfection

How to Avoid Unstable Results When Performing High-Throughput qPCR

 :: Posted by American Biotechnologist on 04-28-2010

If your biotechnology research requires you to be engaged in high-throughput Quantitative PCR analysis than you’ve probably made good use out of automated systems such as liquid handling robots and plate stackers. And what a relief they are. Imagine what your poor thumb would feel like if you had to pipette out tens of thousands of reactions. Or think about how much time you would have wasted standing around waiting for a run to end in order to load the next plate into the QPCR machine.

While automated handing systems are fantastic, they also bring with them the complicated question of sample stability. When samples are loaded into the automated system, they may be stored there at room temperature for hours. As such, it is important for the reaction mix to be stable at room temperature for the duration of the waiting period.

In this Bio-Rad Technical note, you will learn how Bio-Rad’s SsoFast EvaGreen supermix meets the challenge of providing reaction mix stability and can be used to acheive consistent results over a large dynamic range of templates with automated runs lastng up to 48 hours.

Stability for Automated qPCR