Category: analytical chemistry

Electrospray ionization is the main gentle ionization technique that interfaces with liquid chromatography

May 9, 2024

Gentle ionization techniques have revolutionized the field of mass spectrometry identification of proteins by providing an intact molecular ion that is facile to downstream analysis. One important gentle ionization technique is electrospray ionization (ESI) that remains the dominant technique that interface liquid chromatography with mass spectrometry. Specifically, in ESI, the protein analyte is pass through … More Electrospray ionization is the main gentle ionization technique that interfaces with liquid chromatography

Longer DNA segment needs longer initial melting time for qPCR applications

May 6, 2024

Initial melting step in quantitative polymerase chain reaction (qPCR) is essential to separate the double stranded DNA into single stranded DNA in preparation for PCR. Naturally, the longer the DNA segment, the more energy is needed to separate the strands, and thus, a longer melting time at the same melting temperature of 95 oC is … More Longer DNA segment needs longer initial melting time for qPCR applications

Protein sequencing remains a significant technological barrier in omics research

May 2, 2024

Since the advent of Sanger sequencing in the 1970s, DNA sequencing has revolutionized our understanding of the life sciences, and allowed us to glean new insights into the genetic underpinnings of many diseases and biological phenomena at the cellular level. But, there is relatively little traction in the area of protein sequencing. Currently, we still … More Protein sequencing remains a significant technological barrier in omics research

Time of flight tube allows molecular ion of different mass to be separated using different flight time in MALDI-TOF mass spectrometry

April 29, 2024

Mass spectrometry techniques rely on a mass analyzer to separate ions of different molecular weight in order to afford differential or specific detection of particular molecular ion of certain mass/charge ratio. One common mass analyzer is the quadrupole mass analyzer common in liquid chromatography mass spectrometry (LC-MS) applications. In the gentle ionization technique known as … More Time of flight tube allows molecular ion of different mass to be separated using different flight time in MALDI-TOF mass spectrometry

Gene expression studies inform us of the underlying mechanisms that give rise to an observed phenotype

April 18, 2024

In recent years, gene expression studies have moved into an essential item in many biological studies. Such determination of gene expression pattern could occur at the mRNA or protein level, and helps us understand the molecular underpinnings of certain phenotype at the macroscale. For example, in Escherichia coli cultivated under anaerobic conditions, there is likely … More Gene expression studies inform us of the underlying mechanisms that give rise to an observed phenotype

High fidelity DNA synthesis is now possible with improved technologies and opens up synthetic gene use as positive control in qPCR applications

April 17, 2024

In method development for quantitative polymerase chain reaction (qPCR), there is a need for a reference template in order to assess the binding efficiency and performance of the primers and probe as well as develop a temperature cycling programme for this gene and assay. With improvement in DNA synthesis technologies, now it is possible to … More High fidelity DNA synthesis is now possible with improved technologies and opens up synthetic gene use as positive control in qPCR applications

Synthetic gene affords a wider dynamic range calibration than genomic DNA in qPCR assay development

April 15, 2024

Calibration is an essential step in quantitative polymerase chain reaction (qPCR) assay development. This step of the workflow relates Ct value with the number of copies of template DNA per unit volume. Hence, it gives clinical meaning to a qPCR detection of a pathogen. Typically, genomic DNA of a bacterium can be extracted, diluted, and … More Synthetic gene affords a wider dynamic range calibration than genomic DNA in qPCR assay development

Initial heating in qPCR melts the template DNA in preparation for downstream qPCR reaction

April 12, 2024

Quantitative polymerase chain reaction (qPCR) is the gold standard approach for clinical detection of pathogens. These pathogens are typically microbial in nature, and has a chromosome length of millions of base pair. At such length, there is a need for a fairly lengthy step to melt or unwound the double stranded DNA to separate the … More Initial heating in qPCR melts the template DNA in preparation for downstream qPCR reaction

Secondary antibody in Western Blot is designed to be broad spectrum and gives fluorescence or calorimetric signal to more types of proteins detected by different primary antibodies

April 11, 2024

Western blot can be understood as a narrow spectrum, low throughput gene expression profiling tool at the protein level. In this commonly used assay, primary and secondary antibodies need to be used in conjunction to afford visualisation of specific protein bands on the membrane after transfer from the polyacrylamide gel. In Western blot, the primary … More Secondary antibody in Western Blot is designed to be broad spectrum and gives fluorescence or calorimetric signal to more types of proteins detected by different primary antibodies

Gentle ionization for mass spectrometry preserves the molecular ion and aids in compound identification

April 9, 2024

About 20 years ago, a suite of gentle ionization techniques such as electrospray ionization (ESI) and matrix assisted laser desorption/ionization (MALDI) are incorporated into commercial mass spectrometers, and revolutionized the way we detect and characterise the molecular ion. By molecular ion, we refer to the intact compound ion without any fragmentation. It can be seen … More Gentle ionization for mass spectrometry preserves the molecular ion and aids in compound identification