Programmed cell death, or apoptosis, occurs tens of millions of times every day in every human body. Researchers in South Korea have devised an easy method to detect apoptotic cells by fluorescence, as they report in Chemistry—An Asian Journal. Their method makes it easier to detect imprope ... more
Written in Red
Red-Emitting Dyes for Optical Microscopy and Nanoscopy
08-07-2010: Far-field optical nanoscopy methods, especially STED (stimulated emission depletion), pose very strict and, at times, contradictory requirements on the utilized fluorescent markers. Photostable fluorescent dyes that absorb in the red optical region are indispensable as labels for various micro- and nanoscopic studies (e.g., with commercially available STED microscopes). Despite many attempts to design novel and improved red-emitting dyes, the number of compounds that perform satisfactorily in fluorescence-based microscopy is still limited. Because of this, a great deal of research is being carried out by a large multidisciplinary team headed by Prof. Stefan W. Hell at the Department of NanoBiophotonics in Max Planck Institute for Biophysical Chemistry (Göttingen). In their recent paper published in the European Journal of Organic Chemistry the team describes a general synthetic route to new improved carbopyronine dyes and their performance in confocal and STED microscopy.
The new dyes have large fluorescence quantum yields, high water solubility, and the required positions of the absorption and emission bands in the red. The chemists came up with a synthetically feasible structural scaffold with functional groups that can be varied in the final steps of the synthesis or even in the resulting fluorescent dye to fit a given task. According to Dr. Kirill Kolmakov, who performed the synthesis, his “table book” contained a dissertation and articles and patents by Prof. K. Drexhage and co-workers, whose contribution to the synthesis of carbopyronines is fundamental. However, the synthetic approach presented in their article is by far more flexible and improved. In particular, it starts from one simple precursor and utilizes a minimum amount of protecting groups. The key feature of the general strategy described therein is the interplay of certain protecting groups. Protecting groups will take an even more important part in the design and synthesis of caged carbopyronines and rhodamines that emit in the far-red spectral region. Besides the interesting chemistry, the team demonstrates that the performance of a dye in confocal microscopy and under STED conditions does not necessarily correlate. Dr. Kolmakov thus emphasizes that for their future research work, they will have to reconsider some of their old views on the “ideal” STED dye. All these make the primary article a good example of teamwork that is strategically sound, brilliantly planned, and perfectly delivered.
Original publication: Vladimir N. Belov et al.; "A Versatile Route to Red-Emitting Carbopyronine Dyes for Optical Microscopy and Nanoscopy"; European Journal of Organic Chemistry 2010, No. 19, 3593–3610.
Label free optical biosensors enable the monitoring of biomolecules and their interactions in often highly sensitive diagnostic assays. Several methods have been employed for this purpose, including Whispering Gallery Mode (WGM) biosensing, which offers a particularly sensitive approach to ... more
Coherent Raman scattering methods have one key advantage over spontaneous Raman microscopy: speed. The (sub-)microsecond pixel dwell times offered by narrowband CRS imaging methods have initiated a new era of chemical imaging applications in biology and biomedicine.Biomedical scientists are ... more
Am Fassberg 11
To explore the most intricate structures of the brain in order to decipher how it functions – Stefan Hell's team of researchers at the Max Planck Institute for Biophysical Chemistry in Göttingen has made a significant step closer to this goal. Using the STED microscopy developed by Hell, th ... more
Prof. Dr. Dr. h. c. Stefan Hell of the Max Planck Institute for Biophysical Chemistry in Göttingen is to receive the 2011 Körber European Science Prize endowed with 750,000 euros for his pioneering discoveries in the field of optics. Every year, the Körber Prize is awarded to an outstanding ... more
Far-field optical nanoscopy methods, especially STED (stimulated emission depletion), pose very strict and, at times, contradictory requirements on the utilized fluorescent markers. Photostable fluorescent dyes that absorb in the red optical region are indispensable as labels for various mi ... more
- 1Thermo Fisher Scientific to Acquire Life Technologies Corporation
- 2Schleicher & Schuell has been purchased by Whatman plc
- 3analytica Vietnam 2013 – Platform for innovations
- 4Inspecting water quality with Raman spectroscopy
- 5LIMS/LIS Market and POCT Supplement
- 6X-ray analysis could boost legumes, thus reducing fertilizer pollution
- 7Abbott Completes Acquisition of Advanced Medical Optics
- 8MDS Sciex Opens Manufacturing Facility in Singapore
- 9Troubling levels of toxic metals found in lipstick
- 10Analytik Jena announces forecast for financial year 2012/2013
- Chemistry breakthrough sheds new light on illness and health
- Detecting harmful dye used to make ketchup red
- Targeted screening for C. difficile upon hospital admission could potentiall ...
- Troubling levels of toxic metals found in lipstick
- Core facilities: Widening access to research instrumentation
- Carl Zeiss Meditec improves its results in first six months of financial year 2012/2013
- Evonik selects OPX Biotechnologies for joint development of bio-based chemicals
- ZEISS presents half-year financial figures
- Analytik Jena to develop products for sepsis diagnostics
- Analytik Jena AG establishes subsidiary in Thailand