Author Archives: Steven Miles

Thin Layer Chromatography and Ophthalmology

This bit of insight comes from our friends at Medical Blog.

A variety of genetic, metabolic, developmental, and idiopathic causes can result in congenital clouding of the cornea. A common reason for congenital clouding of the cornea is congenital glaucoma. Other major causes of corneal clouding include the following: Birth trauma Peters anomaly Dermoid tumors (limbal dermoids) Sclerocornea Congenital hereditary endothelial dystrophy (CHED) Mucopolysaccharidoses Infectious/inflammatory processes The following is a mnemonic for the causes of congenital clouding of the cornea: S – Sclerocornea T – Tears in the Descemet membrane secondary to birth trauma or congenital glaucoma U – Ulcers M – Metabolic P – Peters anomaly E – Edema (CHED) D – Dermoid Other rarer causes of congenital clouding of the cornea include the following: cornea plana, corneal keloids, oculoauriculovertebral (OAV) dysplasia (Goldenhar-Gorlin syndrome), congenital corneal ectasia, congenital hereditary stromal dystrophy, posterior polymorphous dystrophy, and Fryns syndrome.

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A 4-month-old male infant had severe corneal opacity since birth. Examination revealed buphthalmos, increased IOP, and corneal opacity with neovascularization but not a dysmorphic face or hirsutism. The liver and spleen were impalpable. Hypotonia, poor head control, and absence of Moro and grasping reflexes were noted. He had no evidence of congenital infection (toxoplasmosis, other infections, rubella, cytomegalovirus infection, and herpes simplex [TORCH] study). Urine and plasma amino acid levels were normal. However, thin-layer chromatography showed excessive urinary excretion of heparan sulfate. Corneal transplantation was performed at 6 months of age. Histopathology of the corneal button showed homogeneous thickening of the Bowman layer and pinkish intracytoplasmic substances in the corneal stroma. The Alcian blue stain was positive, consistent with MPS of the cornea.

Click Here to read the full report.

Information Directory on Thin Layer Chromatography

Adiwebs.com is an online information directory. It provides useful information on a variety of topics. Thin Layer Chromatography

The site has a great write up on Thin Layer Chromatography – here’s some excerpts:

Thin layer chromatography is adsorption chromatography performed on open layers of adsorbent materials supported bon glass plates. This technique combines many of the advantages of paper chromatography with those of column chromatography.

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Superiority of TLC:

The superiority of TLC over paper chromatography lies in the following facts:

Because of the inorganic nature of the adsorbent (supporting medium), concentrated sulfuric acid spray followed by heating may be used to develop (or locate substances on) the chromatogram by charring and rendering visible any spots of organic nature.
Moreover, amino acid mixtures, which require 18 hours for separation on paper, require as little as 3 hours using cellulose TLC.
The advantage of this technique also lies in the choice of the adsorbents which allow separation not possible on paper.

Click Here to read more from Adiwebs.com

Thin Layer Chromatography and Skin Care

One of the regular questions we get is, “where is Thin Layer Chromatography used?” To which we respond, pretty much everywhere.

For one example you probably wouldn’t expect, check out Fresh Faced Skin by clicking here.

What are some examples you’ve seen of Thin Layer Chromatography applications?

Monty Python and Thin Layer Chromatography – the “I’m Not Dead Yet” chemical

Chemical & Engineering News just published a fascinating Ants piece about how ants let other ants know whether they are dead or not.

Of course, the whole piece starts off with a reference to Monty Python’s great “I’m not dead yet” scene from the Holy Grail. It’s good to see yet another connection between Monty Python and Chromatography!

Here’s an excerpt from the article:

By using thin-layer chromatography and gas chromatography to compare live, just-killed, and dead ants, the team showed that a subset of chemicals disappeared from the ants’ outer covering within one hour of death. From those extracts they identified two rapidly dissipating “do not discard” signaling chemicals—specific isomers of the natural products dolichodial and iridomyrmecin.

Click Here to read more and view the video.

Delaware BioScience Association Awards Gala a Great Success

Gov. Markell and Delaware Bio Honors AstraZeneca for 10 Years in State

Award recipients recognized for Innovation, Service, and Excellence in Government

Members of Delaware’s bioscience community honored three industry leaders at the Delaware BioScience Awards Gala Delaware Bio Annual Awards Gala on Wednesday, April 29. We also celebrated the ten-year anniversary of AstraZeneca’s decision to locate its U.S. headquarters in Wilmington, Delaware. celebrating at Delaware BioScience Awards Gala

Recipients of the 2009 Delaware Bio awards, which go to individuals who have made outstanding contributions to the biosciences in Delaware are:

Innovation: Dr. Barry Marrs, Chief Scientific Officer of Athena Biotechnologies,

Service: Dr. David Weir, Director of the Office of Economic Innovation and Partnerships (OEIP) at the University of Delaware,

Government Official: Senator Thomas R. Carper, United States Senate.

The keynote speaker for the evening was Delaware Governor Jack Markell and many in the room had stories to share about AstraZeneca’s decision to locate their U.S. headquarters in Delaware.

Delaware BioScience Gala

Thin Layer Chromatography used in identifying Sixth Nucleotide

From our friends at GenomeWeb.com:

Two researchers from Rockefeller University have identified a new nucleotide… Synthesis of IMP

While evaluating 5-methylcytosine levels in two types of mouse brain cells, the team detected a nucleotide that they could not identify. When they looked more closely at this nucleotide using thin layer chromatography, high pressure liquid chromatography, mass spectrometry, and other approaches, the researchers discovered that they were dealing with 5-hydroxymethylcytosine, a form of methylated cytosine found stably in bacterial viruses.

Their subsequent experiments suggest the nucleotide is enriched in brain cells but apparently absent from several other cell types. Based on these findings, the researchers speculated that 5-hydroxymethylcytosine may contribute to epigenetic regulation, particularly in neurons.

Click Here to read more from GenomeWeb.com

First COLOR HPLC Column sold in the world!

We have just sold our first COLOR HPLC Column!

Yes, that’s right – it’s an Orange Ion Exchange DEAE-Column 5 um particle size, 100Å pore size, 150 mm long with a 4.6 mm Inner Diameter.

The new COLOR HPLC Columns are being offered with a wide variety of sizes and packings, from C8 and C18 silica to methyl, ethyl, butyl, phenyl, and triacontyl.

Think about it – no more standing around with a bunch of columns that look exactly alike wondering, “which one of these is the C18 and which one is the C8?”

To check out all of those varieties and colors, click here.

Thin Layer Chromatography used in DNA aging research

Excerpts from a paper posted on the U.S. National Library of Medicine and the National Institutes of Health web site DNA strands titled:

TLC-based detection of methylated cytosine: application to aging epigenetics

5-Methylcytosine (m(5)C) has a plethora of functions and roles in various biological processes including human diseases and aging. A TLC-based fast and simple method for quantitative determination of total genomic levels of m(5)C in DNA is described, which can be applicable to aging research with respect to rapid and high throughput screening and comparison. Using this method, an example of the analysis of global alternations of m(5)C in serially passaged human skin fibroblasts is provided, which shows age-related global hypomethylation during cellular aging in vitro.

Click Here to access the paper.

Training the next generation in Biotechnology

St. Georges Technical High School has a stellar St. Georges Biotech Open House Biotechnology Program and the program’s director, Florence Malinowski, M.S., is happy to share what her students are learning.

St. Georges students demonstrate Elisa Lab At the programs’ first Open House, students demonstrated a wide variety of lab techniques – from DNA extraction to Gel Electrophoresis to Chromatography.

The following are excerpts from an article by Edward L. Kenney about the open house published by the News Journal:

Students, mostly juniors who are looking for summer internships and cooperative employment opportunities, showed off their skills at eight lab stations as employers took the opportunity to talk with them about what they were doing.
Student demonstrates chromatography at St. Georges High School
Junior Gina Peirce, 17, worked with a mortar and pestle, crushing spinach leaves and removing the juice for analysis.

“We’re finding out different pigments that are in spinach,” said Gina, who does not know yet what career she would like to pursue. “A lot of people came to this station and asked about this. It’s a really good opportunity for companies to see what we’re doing here at St. Georges.”

The first class will graduate next year, so many of the students also are looking at higher education. Among the college representatives at the open house was Joan Barber, the chairwoman for the biology and chemistry department at Delaware Technical & Community College’s Stanton Campus, which offers associate degree programs in biotechnology and chemistry technology.

“These students would be wonderful for our program,” she said. “They would be very well prepared. They’ve had a lot of introduction to things that we would be teaching them at DelTech.”

Below are a series of comments from some who attended the Open House:

Joan Barber, Ph.D., Chairperson of the Biology & chemistry Department with Delaware Technical & Community College

Ben Hsu, Ph.D. MBA, Chief Financial Officer with QPS

Nancy Wagner, Executive Director of Community Relations with Delaware State University

Russ Booth with the DuPont Company

Delaware BioScience Association President Bob Dayton

Patricia Jones with the University of Delaware

Florence Malinowski, M.S., Biotechnology instructor with St. Georges Technical High School

CDC recommends Thin Layer Chromatography to test anti-malarial drugs

The U.S. Centers for Disease Control and Prevention advise that, “Counterfeit (fake) drugs are products deliberately made to resemble a brand name pharmaceutical. They may contain no active ingredients or contain ingredients inconsistent with the package description.”
Malaria treatment
For example, the CDC says, “In Cambodia in 1999, counterfeit antimalarial drugs were responsible for the deaths of at least 30 people. A recent survey in Southeast Asia showed that among 104 tablets presented as the antimalarial drug artesunate, 38% did not contain any artesunate.”

Users of pharmaceutical products (not only antimalarials) should take the following precautions:

Travelers should purchase in advance, in their home country, all the medicines they will need.
Travelers should record the drug’s generic and brand names as well as the name of the manufacturer; should they run out, they can look for the correct product.
Make sure that the drug is in its original packaging.
Inspect the packaging because many times poor quality printing indicates a counterfeited product.
Be suspicious of tablets that have a peculiar odor, taste or color, or that are extremely brittle.

The CDC recommends testing suspicious drugs.

“drug quality can be evaluated in the field by two simple, effective, and low-cost techniques: thin-layer chromatography (TLC) and colorimetry… The TLC technique consists of placing a spot of drug sample on a thin layer of silica attached to a plate of glass, aluminum, or plastic. The plate is then inserted into a vessel containing a solvent mixture. By capillary action, the solvent mixture creeps up the silica material and dissolves the sample. The drug sample consists of a mixture of drug and inactive ingredients. These compounds will have various affinities to the silica matrix and will migrate with the solvent at various speeds. This characteristic effectively separates out a mixture of compounds. After migration of the solvent is complete, individual components can be visualized by chemical treatment or ultraviolet (UV) absorbance. The distance that the components migrate is characteristic for each compound; therefore the active ingredient can be recognized by comparison with a known drug standard. The solvent can be modified to increase resolution between various components. This method is relatively inexpensive, specific, and sensitive. It is commonly used to assess drug quality.”

Click Here for more details from the CDC.

Click Here to find out more about Thin Layer Chromatography plates and accessories.

Miles Scientific

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