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Alex Chen

Alex received his Ph.D in Immunology and Virology at the University of Massachusetts. He then worked at Sanford Burnham Medical Research Institute and University of Toronto as a post-doctoral researcher studying viral immunity and biology of HIV. He is currently an active member at bitesize bio. He is looking forward to endless opportunities in medical writing and collaborative communication writing.

Articles by Alex Chen:

Codon Optimization 101

The intriguing thing about protein expression is that the combination of transfer RNAs (tRNAs) that translate the 3 letter codon into an amino acid (aa) far exceeds the number of existing amino acids (aa). If you do the math correctly, the maximum number of unique combinations using the triplet code to code for the 4…

23 Aug 2017 Genomics & Epigenetics

Using Synthetic DNA For Long Term Data Storage

The amount of data requiring long-term storage is growing and accelerating. Current long-term digital storage technology cannot keep up. Imagine roughly 2.5 QUINTILLION bytes of data being created everyday in this world1–2 as more computers and network infrastructure come online. For average users, a long-term storage solution is probably not an issue. However, organizations and…

10 Jul 2017 DNA / RNA Manipulation and Analysis

A Primer on Checking the Methylation State of the Genome

We all know that genes encode proteins that make up a living cell. However, the level and coordination of gene expression is really the key to the success of a living cell. One way eukaryotic cells (that’s us!) control protein expression is through addition of a methyl or hydroxymethyl group on the cytosine nucleotide. This…

04 Apr 2017 Genomics & Epigenetics

Small Particles (Things) Matter!- Introducing Nanoparticle PCR

There are many different methods and protocols on making your PCR  run more efficiently. I recently came across an interesting PCR method called “nanoparticle” PCR. This method seems to attract a lot of attention, because it enhances a PCR  by a few orders of magnitude. More interestingly, while the enhancement effect has been reported in a…

02 Mar 2017 PCR, qPCR and qRT-PCR

An Introduction to MassTag PCR

New ways to perform PCR emerge all the time. This speaks for the speed of technological advances, and reflects the ongoing need to keep up with fast-moving research. We all know that PCR’s main purpose is to amplify a stretch of nucleic acids based on sequence-specific primers. Nowadays, a wide range of PCR techniques exist,…

16 Feb 2017 PCR, qPCR and qRT-PCR

CRISPR Technology Explained: Towards a CRISPR Genome!

If you are working in the biomedical research field and you haven’t yet heard about CRISPR Cas9 gene editing technology, you have some catching up to do – but don’t worry, this article will bring you up to speed about CRISPR in no time! In the few years since the CRISPR phenomenon emerged, this technology has…

25 Jan 2017 DNA / RNA Manipulation and Analysis

A New Frontier in Protein Quantitation: AlphaLISA

If you ever worked in a biology or biochemistry laboratory, you probably already heard about ELISA. You may have even used it. But do you know what’s behind it? And how you can improve it? Let me guide you through the basics of ELISA, and introduce you to my favorite ELISA technique—AlphaLISA. First Things First… So,…

17 Jan 2017 Protein Expression & Analysis

Hydrodynamic Focusing in Flow Cytometry

If you have sorted samples or phenotyped cells by surface expression of proteins, you’ve probably wondered how each cell is sorted or phenotyped in a flow cytometer? This question seems trivial, but in reality it took a while for engineers to figure it out. Before I get into today’s topic on “hydrodynamic focusing,” I’ll walk…

10 Jan 2017 Flow Cytometry

Multiplex Cytometric Bead Array: The ABCs of CBAs

Multi-parameter data acquisition is key to the modern era of science research. I, for one, wish every single experiment that I design would give me the maximum amount of information. For example, in cell biology and immunology, we want to capture as much information (be it cytokines/hormones/chemokines) as possible about a given cell population. Of…

13 Dec 2016 Flow Cytometry

Analyzing Cell Signaling with Flow Cytometry: Go with the Flow

Phosphorylation Equals Cell Signaling! How do cells communicate and respond to their environmental cues? This question has been on the hot list for scientists ever since the discovery of the cell. Cells use signaling cascades based on biochemical reactions to deliver or receive messages. How cool is that? The major secret of cell signaling was…

11 Oct 2016 Flow Cytometry

Choosing the Right E. coli Strain for Transformation

Cloning, purifying, and expressing modified genetic material is routinely done in microbes such as Escherichia coli (E.coli). Relatives of this molecular biology workhorse normally live in the intestinal track of humans. The particular E. coli strain (K-12) that scientists use all over the world was isolated from the feces of a diphtheria patient in 1922.1…

29 Sep 2016 DNA / RNA Manipulation and Analysis

A Biologist’s Guide to Choosing Your Fluorophore Palette

You may notice that nature is full of vibrant, even fluorescent, colors. The human eye detects wavelengths ranging from 390-700 nm and our perception of colors is actually a narrow part of the light spectrum. Other organisms can detect color from a wider spectrum. Why do colors exist? Arguably, colors are communicative, from tropical fish…

01 Sep 2016 Flow Cytometry&Microscopy & Imaging

How to Make Your Own Chemically-Competent Cells

I once had the terrible experience of not being able to run an assay because I ran out of commercial stock of transformation-competent Escherichia coli (E.coli). From that day, I learned to make my own chemically-competent cells in the lab. I recommend that everyone makes their own stash of transformation-competent E.coli stocks—among other suggested laboratory…

31 Aug 2016 DNA / RNA Manipulation and Analysis

Top 5 Tricks for Using FlowJo

Are you planning to do cellular immunology research?  Then chances are you will be introduced to the flow cytometer –  “a modern immunologist’s best friend.” This modern magic box is a highly versatile machine packed with cutting-edge fluidics and photonics (lasers). Combined with the monoclonal antibodies conjugated to fluorochromes capable of emitting light signals from a…

09 Aug 2016 Flow Cytometry

A Guide to Solid Phase Reversible Immobilization

  Scientists today depend heavily on many molecular biology techniques to perform their research. For example, with the advent of next generation sequencing (NGS): scientists are able to look at very minute details, right down to individual genetic sequence variations. However, the increase in experimental complexity means that every extra step becomes more crucial than…

11 Jul 2016 DNA / RNA Manipulation and Analysis

How to Quantify Integrated HIV Genomes Using Alu-gag PCR

Alu sequences are repetitive DNA sequences that are widely dispersed within the human genome. These “junk DNAs” are not as useless as one might think. An interesting method to use them is to quantify the number of integrated Human Immunodeficiency Virus (HIV) genome copies using Alu-PCR.

09 Jul 2016 PCR, qPCR and qRT-PCR

Single Molecule Real-Time Sequencing

Recently, I have witnessed the uprising of various next generation sequencing (NGS) platforms and it’s quite interesting because each platform uses a different method. Previously, I’ve written about the exciting possibility of nanopore sequencing—a new sequencing technology based on the “signature” electrical currents generated as a single strand of DNA passes through the nanopore. The…

09 Jul 2016 Genomics & Epigenetics

Photonic PCR: When Lightening Strikes Your DNA

Before I get into today’s topic, please allow me to digress a bit and start with a few sentences that sum up the polymerase chain reaction (PCR); the grand-daddy of molecular biology. PCR, a method that is at the heart of modern day molecular biology discoveries, is a process that amplifies genetic material through our…

09 Jul 2016 PCR, qPCR and qRT-PCR

Long-Range PCR: It’s About Choosing the Right Enzyme

The ability for DNA polymerase to copy a long stretch of DNA is becoming increasingly important. Why? It has to do with the advances in our sequencing technologies. Our next generation sequencing (NGS) technology requires the DNA polymerase to copy a long stretch of DNA (sometimes up to 50kb) as NGS is churning out genetic…

09 Jul 2016 PCR, qPCR and qRT-PCR

Locating Your Cellular Apoptosis Squad: Annexin V Staining Assays

In real life, cells are instructed to commit suicide for the greater good of the organism. The programmed cell death (apoptosis) is important during development of a multi-cellular organism. A good example you will appreciate is the dis-appreance of the tail from a tadpole as it turns into a frog. On the reverse, the lack…

09 Jul 2016 Flow Cytometry