Mush
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Digitally Enhanced Thin-Layer Chromatography (DE-TLC)
Cheap and relatively easy tool for quantitative determination by TLC. 
Digitally Enhanced Thin-Layer Chromatography: An Inexpensive, New Technique for Qualitative and Quantitative Analysis
Amber Victoria Irish Hess
Massachusetts Institute of Technology, Cambridge, MA 02139-4310
J. Chem. Educ., 2007, 84 (5), p 842
DOI: 10.1021/ed084p842
Publication Date (Web): May 1, 2007
The objective: Thin-layer chromatography (TLC) is a widely used method for qualitative analysis to determine the number of components in a mixture, to
determine the identity of two substances, or to monitor the progress of a reaction.
The more accurate high-performance TLC (HPTLC) is better suited for quantitative analysis. Unfortunately, HPTLC requires expensive equipment which
most high schools and colleges cannot afford.
I demonstrate that if digital photography is combined with regular TLC, it can perform highly improved qualitative analysis as well as make accurate
quantitative analysis possible.
Methods/Materials
This novel, "digitally-enhanced" TLC (DE TLC) is very easy to use. A fluorescent TLC plate is illuminated with UV light and a picture of the plate is
taken with a digital camera. Then, on a computer, using either TLC Analyzer, the public domain software I wrote, or common photo-editing software, one
can quickly produce multi-spectral scans, densitograms, and calibration curves--output previously available only from more expensive equipment or
complex procedures
Results
With high linearity (R^2 ~ 0.97 - 0.99), good repeatability RSD < 5%), and detection limits approaching those of HPTLC, DE TLC produces
surprisingly good results for such inexpensive equipment..
Conclusions/Discussion
Digitally-Enhanced TLC is a valuable tool that can be added to every chemist's TLC toolbox. Since this technique is much less expensive than other
quantitative chromatographic methods, DE TLC is ideal for high school and college labs.
This project developed an inexpensive technique using digital photography that is an alternative to a $30,000 piece of equipment for chemical
analysis.
This is her blog:
http://www.sciencebuddies.org/science-research-papers/tlc_an...
Anyone can contact her by email for further questions regarding to this method.
J Labelled Comp Radiopharm. 2013 Sep;56(11):544-52. doi: 10.1002/jlcr.3052. Epub 2013 Jul 23.
Digitally enhanced thin layer chromatography: further development and some applications in isotopic chemistry.
Improvements to thin layer chromatography (TLC) analysis can be made easily and cheaply by the application of digital colour photography and image
analysis. The combined technique, digitally enhanced TLC (DE-TLC), is applicable to the accurate quantification of analytes in mixtures, to reaction
monitoring and to other typical uses of TLC. Examples are given of the application of digitally enhanced TLC to: the deuteromethylations of
theophylline to [methyl-(2)H3]caffeine and of umbelliferone to [(2)H3]7-methoxycoumarin; the selection of tertiary amine bases in
deuterodechlorination reactions; stoichiometry optimisation in the borodeuteride reduction of quinizarin (1,4-dihydroxyanthraquinone) and to the
assessment of xanthophyll yields in Lepidium sativum seedlings grown in deuterated media.
DE-TLC; Lepidium sativum carotenoids; [2H3]7-methoxycoumarin; [9,10−2H2]1,4-anthraquinone; deuteromethylation; digitally enhanced TLC;
methyl−2H3]caffeine; quinizarin; umbelliferone
Less advanced technic but based on the same principle.
Quantitative and Qualitative TLC Analysis of 5meo DMT
By Clear Light and Desert Sun
https://erowid.org/archive/rhodium/pdf/5-meo-dmt.quant-qual....
Attachment: 10.1002@jlcr.3052_Digitally enhanced thin layer chromatography.pdf (775kB)
This file has been downloaded 505 times
[Edited on 4-12-2016 by Mush]
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Mush
International Hazard
Posts: 584
Registered: 27-12-2008
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12-2018
Studies in hydrogel microfluidics and developmentof low cost imaging for quantitative TLC in the undergraduate teaching laboratory
Alexandra Marie
Anderson University of Tennessee
....For this undergraduate lab, we chose the approach of digitally-enhanced TLC (DE-TLC), which combines a digital camera with regular TLC equipment
to enable quantitative analysis (10). DE-TLC was introduced in 2007 with an accompanying public domain analysis software, but the softwareis now
obsolete and inoperable on many modern computer systems. In this work, the DE-TLC method was revisited using free public domain software(i.e.NIH
ImageJ) for quantitative TLC analysis using indirect fluorescence detection. To interest students, counterfeiting of the anti-malarial drug
chloroquine was chosen as the proposed application.
https://trace.tennessee.edu/cgi/viewcontent.cgi?article=6772...
An Image Analysis System for Thin-Layer Chromatography Quantification and Its Validation
Tang Tie-xin and Wu Hong*
Abstract
Quantitation of thin-layer chromatography (TLC) using image analysis is attractive for its low cost and convenience. The image analysis is
investigated by designing a digital imaging system with simple equipment, developing an image analysis software based on our algorithm, and validated
the system in the TLC quantitative assay of cichoric acid present in Echinacea purpurea (L.) Moench. TLC used a polyamide thin-layer plate with
chloroform-methanol formic acid-water (3:6:1:1) as the mobile phase and 3% (m/v) aqueous aluminum chloride solution as the visualization reagent.
Images are acquired with a standard digital camera under a UV viewing lamp (365 nm) in a dark room. The three-dimensional grayscale digital image
dataset (x, y, gray) is reduced to twodimensional dataset (distance, accumulative gray) and then plotted as a curve. The area under the peak
corresponding to the cichoric acid spot is integrated and used for quantitation. The whole method was validated by the assay tests of detection limit,
calibration curve, repeatability, reproducibility, and recovery. The results showed that our digital imaging method and image analysis algorithm were
applicable for the quantification of TLC. The whole method is convenient, efficient, and moderately accurate for the quantitative assay of cichoric
acid present in Echinacea purpurea (L.) Moench.
Attachment: tie-xin2008.pdf (341kB)
This file has been downloaded 301 times
Software for Image Analysis
Profiles of five programs for quantifying data from Westerns, dot blots, gels, and colony cultures
https://www.the-scientist.com/lab-tools/software-for-image-a...
[Edited on 12-9-2019 by Mush]
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Mush
International Hazard
Posts: 584
Registered: 27-12-2008
Member Is Offline
Mood: No Mood
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A Toolkit to Quantify Target Compounds in Thin-Layer-Chromatography Experiments
Niamh Mac Fhionnlaoich, Stuart Ibsen, Luis A. Serrano, Alaric Taylor, Runzhang Qi, and Stefan Guldin*
J. Chem. Educ. 2018, 95, 12, 2191–2196
| Code: | https://pubs.acs.org/doi/10.1021/acs.jchemed.8b00144 |
Abstract
Thin-layer chromatography (TLC) is one of the basic analytical procedures in chemistry and allows the demonstration of various chemical principles in
an educational setting. An often-overlooked aspect of TLC is the capability to quantify isolated target compounds in an unknown sample. Here, we
present a suitable route to implement quantitative analysis in a lesson plan. We provide both a stand-alone software and an online webapp that allow
students to obtain quantitative information from a developed TLC plate and present two suitable experiments, namely, the absorbance-based
quantification of the colorant Sudan IV and the fluorescence-based quantification of rhodamine 6G, a fluorophore widely used in biotechnology.
Students conduct TLC experiments following established protocols, take pictures of their TLC plates with mobile phones, and subsequently quantify the
different compounds in the separate bands they observe.
The Supporting Information is available on the ACS Publications website at DOI: 10.1021/acs.jchemed.8b00144.
Supporting Information with qTLC software and webapp tutorials; details on MinPeakProm, Divisor, the signal-integration process, and background
subtraction; image-acquisition guidelines; choice of concentration range; and overview of experimental errors (PDF)
Student handout with instructions on experimental TLC (PDF)
Student handout with instructions on image analysis and data acquisition with the qTLC software (PDF)
Student handout with instructions on image analysis and data acquisition with the qTLC webapp (PDF)
All MATLAB components for customization and further development of the qTLC software (ZIP)
Links for installation of the qTLC software on MacOS with separate MATLAB Runtime installation, standalone installation of the qTLC software on MacOS,
installation of the qTLC software on Windows with separate MATLAB Runtime installation, and standalone installation of the qTLC software on Windows
(PDF)
Video
| Code: | https://www.youtube.com/watch?v=rSNVhVJRvws |
qTLC A webapp to quantify chemical compounds via thin layer chromatography.
Attachment: acs.jchemed.8b00144.pdf (3.4MB)
This file has been downloaded 102 times
Application of smartphone in detection of thin-layer chromatography: Case of salvia miltiorrhiza
Journal of Chromatography A 1637 (2021) 461826
Abstract
In this work, a smartphone-based device was constructed for thin-layer chromatography (TLC) detection and semi-quantitative analysis of the components
of Salvia miltiorrhiza . The key construction and shoot- ing parameters were investigated by the relative peak area and signal-to-noise ratio. The
best conditions were as follows: shooting height, 17 cm; angle between the UV lamp and TLC plate, 58 °; exposure com- pensation, 0~0.2 EV; and
shutter speed under daylight and UV 365 nm, 1/50 s and 1/5 s, respectively. These ideal conditions could be replicated by smartphones from different
brands with different versions of software. With good precision, repeatability and stability, the developed device was used for the semi- quantitative
analysis of salvianolic acid B, rosmarinic acid, cryptotanshinone, tanshinone I, tanshinone IIA, and miltirone in the TLC analysis of 10 batches of S.
miltiorrhiza . The results were compared with those obtained by a TLC densitometric scanner and two common types of image processing software, i.e.,
Gel- analyzer and ImageJ . Except for salvianolic acid B in the TLC densitometric scanner, all results were not significantly different among these
methods, which suggested that smartphones might be a useful tool for the quality control of traditional Chinese medicines.
Attachment: j.chroma.2020.461826.pdf (1.6MB)
This file has been downloaded 151 times
Attachment: j.chroma.2020.461826.sup.docx (1.9MB)
This file has been downloaded 121 times
[Edited on 2-8-2021 by Mush]
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