Science advances: the team of academician Chen Hongyuan of Nanjing University has made progress in "nano laser probe"

Recently, the team of academician Chen Hongyuan of School of chemistry and chemical engineering of Nanjing University has made important progress in the light-emitting probe based on plasma laser system Relevant achievements were published in science advanced (DOI: 10.1126 / sciadv.aat0292) with the title of "three-level probe for next generation luminescent nanoprobe" Song Pei and Wang Jianhua, Ph.D students of the school of chemistry and chemical engineering, are the co first authors of the paper, and Chen Hongyuan, Professor Xu Jingjuan and Associate Professor Kang bin are the co authors of the paper The advanced development of modern life science and medicine depends to a large extent on the advancement and development of luminescent probes In the past decades, human beings have created a series of luminescent substances, which have been widely used in basic research, medical diagnosis and chemical industry These luminescent probes include: organic fluorescent dyes, semiconductor quantum dots, fluorescent proteins, up conversion fluorescent materials, bioluminescent molecules and so on Using different color luminescent probes, we can observe the cooperative behavior of many kinds of biomolecules in biological system, or analyze the disease markers with many characteristics at the same time The luminescence behaviors of these probes are all based on spontaneous emission and have a wide emission spectrum distribution This wide spectrum of luminescent characteristics limits the variety of luminescent probes that can be labeled and detected at the same time If we can change the luminescent behavior of the luminescent probe from the source of physical properties, and make it appear monochromatic like laser, it is expected to greatly expand the allowable channel number of life analysis However, the previously reported two-level plasma laser system is still far away from practical biological applications In order to realize the stimulated radiation amplification of light in nanometer scale, we must design and control the gain medium and the electronic transition and energy transfer in the resonator precisely, so as to reduce the threshold value of excitation, extend the time of excitation and meet the requirements of practical biological applications Inspired by the basic theory of laser, the research team designed the electron level of gain medium and used the triple excited state transition of electron to construct the three-level plasma laser probe for the first time Due to the long lifetime of triplet excited states and the quantum rules of spin forbidden, the lasing linewidth of ~ 3 nm, the lasing lifetime of ~ 102 μ s and the lasing threshold as low as 1 MJ cm − 2 are achieved It is compatible with conventional biological detection instruments (such as confocal microscope and flow cytometer) The establishment of the probe design concept is of great significance for the design, development and application of the next generation of new luminescent probes The research has been supported by major scientific research instrument development projects, key projects and general projects of NSFC, and advantageous disciplines of Jiangsu Province Nano laser probe based on three level plasma laser system (source: Science Advanced)