In May 2015, we did a special feature on an Optogenetics red-shifted opsin named JAWS that has a potential future in vision therapy¹. In an effort to continue to support the needs of our customers, Laserglow Technologies has introduced a red wavelength solution (635 nm collimated diode) and offers this as part of a complete optogenetics starter kit. Additionally, Laserglow Technologies in association with Photonics.com is pleased to bring you a FREE webinar on 'Optical Tools for Mapping & Fixing Complex Biological Systems' presented by Dr. Ed Boyden (MIT Media Labs). Register here to watch it now-Photonics.com webinar

Our new, cost effective solution is available to ship from stock, and has many options that can be applied to provide an excellent light source for crux-halorhodopsin (JAWS) and other reagents such as fluorophores. Laserglow also offers 635 nm laser systems in a single transverse profile model for demanding free space users.

Red light penetrates brain tissue more effectively and displays less absorption than blue or green wavelengths, which tend to scatter within the brain. In specific circumstances red light can activate neurons through an intact skull. The red wavelengths can travel farther, reach broader neural regions, and can, depending on the intent of the research, use lower optical powers to achieve very high action potentials, rapidly². In our previous article, we discussed MIT's research with JAWS, where they found that the red shifted opsin produces significantly more nerve cell spiking when exposed to red light.

The most remarkable factor of Optogenetics is the ability to target specific neuronal populations, cell-types and sub-cellular areas, which allows scientists to apply this method in a number of investigations related to the nervous system. Basic brain functions, brain disorders and subsequent treatments can be studied using this approach. It's now possible to express both optogenetic inhibitors and activators within the same cell, and this establishes causal relationships that researchers can use to study the mechanics of cognition and behavior.

The continuous development of optogenetic tools (like channelrhodopsins and inhibitory opsins like JAWS) depends on using molecular and biophysical tools to discover, identify and characterize molecules occurring naturally, and then engineering them to create proteins that are used to exert control over specific neurons³. Molecular engineering plays a crucial part in optogenetic research, which brings together fields like biology, chemistry, botany, cytology and neuroscience.

References:

1. 'Latest News in Optogenetics & Neuroscience' - Wavefront, May 07, 2015: Online Link-Wavefront

2. 'Using Old Knowledge for New Investigations'- N. Scott Browes, LinkedIn Pulse, May 26, 2015: Online Link-LinkedIn Pulse

3. 'Optogenetics- The age of light'- Nature Methods, 29 Sept 2014: Online Link-Nature Methods

Additional Sources:

'Optogenetics Research Opens New Approaches for Brain Mapping, Repair'- Earl Lane, AAAS.org, June 26, 2015: Online Link- AAAS.org

A recent study published by researchers at the University of Toronto demonstrates the effectiveness of Photothermal Ablation Therapy for lung cancer, by using a low-power near infrared (NIR) laser and indocyanine green (ICG) - a cyanine based dye used in medical diagnosis. Laserglow's 808nm laser was used as the illumination source.

Lung cancer is the leading source of cancer-related deaths worldwide. Surgery has been found to be the most effective option for early stage non-small cell lung cancer (NSCLC). In some cases however, the presence of other mutant cells (diseases) compromises the ability of lungs to receive surgery. This necessitates development of methods like photodynamic therapy (PDT) which is a treatment that uses a drug called 'photosensitizer' that when exposed to light of a certain wavelength, would produce singular oxygen that kills nearby cells. PDT has been effective for certain endobronchial tumors, but current lasers are not suitable for tumors in the peripheral lung. Photothermal Ablation Therapy is an adaptation of PDT, where thin laser probes are used to 'heat up' the tumorous cells, thereby destroying them.

The researchers used an 808nm, 250mW laser and ICG to perform 2 in-vitro and 1 in-vivo (transgenic mice) study on human cancer cells. The in-vitro studies involved irradiating the ICG with the laser and observing the responses to the hyperthermic treatment on 3 separate cancel cell lines. It was shown that cancer cell survival rate (and regrowth rate) was inversely proportional to the temperature and time duration of irradiation. The in-vivo study also revealed significant tumor reduction (in some cases, total tumor disappearance) for the 3 mice used in the study.

The study was published in Volume 22, Issue 2 of 'Journal of Bronchology & Interventional Pulmonology' in April 2015. To learn more about the study, methodology and experimental setup involved, read the full paper at: Journal of Bronchology Full Paper

Researchers at MIT have used lasers to bring down the temperatures of molecules to 500 nano-kelvins (about minus 273.15 Celsius), which is just 500-billionths of a degree above absolute zero. It is believed that molecules exhibit very different physical properties at such cold temperatures, and scientists have been trying to study this effect for decades. While cooling atoms has been possible earlier, this is the first time molecules (2 or more atoms chemically connected) have been cooled to this extent.

Lead Physicist Martin Zwierlein cooled down sodium-potassium gas with lasers to dissipate the energy of the individual gas molecules. The density at 500 nano-kelvins is near-zero, so it's comparable to a vacuum state. The team then used evaporation, and then lasers to cool clouds of individual atoms. They then used a magnetic field to get them to stick together and form sodium-potassium molecules. Such molecules are not possible under normal conditions as sodium and potassium are negatively charged and hence, repel each other.

The molecule wasn't very stable and only lasted 2.5 seconds, but the team believes that this is an important step in observing changes in quantum physics at super-cooled conditions. Read more at: Scientific American full article

Additional Resources:

The research was first published in the journal Physical Review Letters Phys. Rev. Lett. 114, 205302