Corporate Banner
Satellite Banner
Scientific Communities
Become a Member | Sign in
Home>News>This Article

Flow Photochemistry: Old Light Through New Windows

Published: Monday, December 17, 2012
Last Updated: Monday, December 17, 2012
Bookmark and Share
This review highlights the use of flow reactors in organic photochemistry, allowing a comparison of the various reactor types to be made.

Flow photochemistry has developed rapidly since the early reports just over 10 years ago. Initial studies focussed on the microflow regime, which itself was born out of the “lab-on-achip” arena. Since then there have been many reports of various well engineered microflow photochemical reactors. Most of these have shown that many photochemical reactions can be carried out with higher yields (space/time) and selectivities and with fewer side reactions than comparable batch reactors. On the whole, however, microreactors are uncompetitive with classic immersion-well batch reactors when it comes to the key issue of productivity. This is unsurprising given the very low reaction volumes and flow rates involved, and as such comparison of two such different reactor topologies is not useful. Microflow reactors are particularly well placed to make best use of the current developments in LED technology. As microflow reactors cannot make use of a large photon flux, much of the radiation from powerful UV lamps is wasted. Use of arrays of compact LEDs is much more suitable and efficient. At the moment LEDs of λ < 365 nm are expensive, prohibitively so at wavelengths of 300 nm and below where a single LED can cost as much €300. This price will come down in future, but it is likely that only a microflow reactor could benefit from this. With further developments photochemical microflow reactors are likely to find many applications, particularly if they can be coupled with automation: screening for new photoreactions, reaction and wavelength optimisation, drug discovery, microactinometers for quantum yield measurements, etc. 

Since its introduction in 2005, the FEP macroflow reactor of Booker-Milburn and Berry has demonstrated that batch-locked reactions can be scaled up from sub-gram quantities to over 500 g per day in a single pass. A flagship example of this was recently reported by Seeberger and Lévesque in their continuous (>200 g per day) synthesis of artemisinin, the current front-line treatment for malaria. Related designs have very recently demonstrated that photocatalysis can be carried out in macroflow devices with high productivities. This is a very significant development as photocatalysis is a powerful emerging area for synthetic chemistry and promises to have wide application. The value of FEP and related tube designs lies in the simplicity of their construction: all the tubing, glassware, lamps and pumps are commercially available at a very economical price and a functioning reactor can be set up in a matter of hours in a standard fume hood. 

With now easy access to flow photochemistry we hope that the synthetic community at large will make more use of photochemical bond-forming reactions and apply them to their general synthetic problems. As way of stimulus, the following provocative question can be asked: can your ground-state chemistry give you easy, clean and reagentless access to 100 g quantities of molecules with high structural complexity? Flow photochemistry can. 

The full review article, written by Jonathan Knowles, Luke Elliott and Kevin Booker-Milburn from the University of Bristol, is available online in Beilstein Journal of Organic Chemistry and is free to access. 

Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,700+ scientific posters on ePosters
  • More Than 3,800+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Sample & Analysis Tracking in Oncogenomic Experiments
The study outlines Onco-STS, a web-based laboratory information management system for sample and analysis tracking in oncogenomic experiments.
Friday, May 08, 2015
Arabidopsis TOE Proteins Involved in the Regulation of Flowering Time
This study found that TOE proteins serve as major integrator of developmental and environmental signaling pathways, especially the photoperiod flowering pathway, triggering flowering at an appropriate age and time.
Wednesday, May 06, 2015
Aflatoxin Biosynthesis - a Novel Source of Reactive Oxygen Species
Researchers at the Michigan State University found that the aflatoxin biosynthetic pathway in A. Parasiticus directly or indirectly generates ROS in aflatoxisomes/endosomes and that Superoxide represents a significant fraction of the aflatoxin biosynthesis-derived ROS pool.
Wednesday, May 06, 2015
SSR Markers and Genetic Diversity in White Birch
The results of this study indicate that the white birch trees sampled from six geographical locations had low to moderate similarity (0.025–0.610) and suggested that the SSR primers used in this study can effectively distinguish white birch germplasm.
Wednesday, May 06, 2015
The Genetics Behind Abdominal Pigmentation in Drosophila melanogaster
This study by researchers at the North Carolina State University provides evidence that genetic variation at a number of steps in regulatory, developmental, and transport pathways may contribute to natural variation in abdominal pigmentation.
Wednesday, May 06, 2015
Selection of Reference Genes for Quantitative RT-PCR Analysis
The expression stability of 12 commonly used reference genes was analysed.
Thursday, April 02, 2015
Improving the Extraction and Recovery of DNA from Cotton Swabs
This study evaluates methods to improve the extraction and recovery of DNA from cotton swabs for forensic analysis.
Tuesday, January 13, 2015
Metabolomics Data Normalization with EigenMS
In this study, a singular value decomposition-based method, called EigenMS, for normalization of metabolomics data was tested.
Wednesday, January 07, 2015
Circadian Variation Of The Human Metabolome
Real-time breath analysis was used to study circadian metabolism.
Wednesday, January 07, 2015
Bridging Quantitative Analysis and Untargeted Metabolomics
Untargeted metabolomics has become a popular tool in metabolite biomarker discovery and in the evaluation of metabolic pathway changes associated with disease.
Thursday, December 04, 2014
Proteomics for Systems Toxicology
MS-based proteomics is maturing into a robust technology for the measurement of proteome-wide exposure effects.
Monday, November 24, 2014
A Continuous Flow System for the Measurement of Ambient Nitrogen Oxides
The proposed method can be used in industrial locations to continuously monitor ambient NOx levels and it can be automated for measuring the variation of NOx concentrations.
Friday, November 14, 2014
Charge-Tagged Proline-Based Organocatalyst for Mechanistic Studies Using ESI-MS
In a comparative continous flow ESI-MS study, researchers use a new charged catalyst and neutral L-proline to investigate the proline-catalyzed inverse crossed aldol reaction of aldehydes with diethyl ketomalonate.
Friday, November 14, 2014
Single-Step Isolation of Extracellular Vesicles by SEC
Researchers from the University of Amsterdam have developed a single-step protocol to isolate vesicles from human body fluids.
Thursday, October 16, 2014
Simple, Rapid and Effective Method for Ammonia Determination
Researchers have a developed a modern, miniaturized and economic flow system to overcome problems of using Nessler's reagent for ammonia determination.
Thursday, October 16, 2014
Scientific News
Education and Expense: The Barriers to Mass Spectrometry in Clinical Laboratories?
Here we examine the perceived barriers to mass spec in clinical laboratories and explore the possible drivers behind the recent shift in uptake of the technology in clinical settings.
Removing 62 Barriers to Pig–to–Human Organ Transplant in One Fell Swoop
The largest number of simultaneous gene edits ever accomplished in the genome could help bridge the gap between organ transplant scarcity and the countless patients who need them.
Biomarker Predicting Transplant Complications May be Key to Treating Them
A protein that can be used to predict if a stem cell transplant patient will suffer severe complications may also be the key to preventing those complications, an international research team based at the Indiana University School of Medicine reported Wednesday.
Potential New Diagnosis and Therapy for Breast Cancer
Scientists at the University of York, using clinical specimens from charity Breast Cancer Now’s Tissue Bank, have conducted new research into a specific sodium channel that indicates the presence of cancer cells and affects tumour growth rates.
First Results Describing Sick Sea Star Immune Response
Though millions of sea stars along the West Coast have perished in the past several years from an apparent wasting disease, scientists still don’t know why.
New Protein Cleanup Factors Found to Control Bacterial Growth
UMass Amherst researchers characterize previously mysterious proteolysis factors.
UC San Diego Team Up with Illumina to Speed-Read Your Microbiome
Data analysis app accelerates studies aimed at using microbes to predict, diagnose and treat human diseases.
Proteins with ALS, Cancer Role Do Not Assume a Regular Shape
Our cells contain proteins, essential to functions like protein creation and DNA repair but also involved in forms of ALS and cancer, that never take a characteristic shape, a new study shows.
Paving the Way for Diamonds to Trace Early Cancers
Researchers from the University of Sydney reveal how nanoscale 'diamonds' can light up early-stage cancers in MRI scans.
Researchers Develop Classification Model for Cancers Caused by KRAS
Most frequently mutated cancer gene help oncologists choose more effective cancer therapies.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,700+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,800+ scientific videos