Biological nascent evolution of snail bone and collagen revealed by nonlinear optical microscopy

Abstract

Using nonlinear optical microscopy of coherent antistokes Raman scattering (CARS), second harmonic generation (SHG) and two-photo excitation fluorescence, we in situ observed how the collagen and the bone grow synergistically and competitively during nascent biological evolution. The sdsCO 2− 3 and PO 2− 3 ions were first observed to be dispersed in the liquid environment, and the collagen was observed 2 days later. With the help of the collagen, the CO 2− 3 and PO 2− 3 ions gradually moved closer to the collagen, and then the bone was produced in the forms of CaCO 3 and CaPO 3 . When the bone was completed with the help of the collagen, the collagen gradually disappeared. The biological evolution of snail bone and collagen can be well revealed by CARS and SHG, and in addition, the biological evolution of structure and morphology can be clearly observed day by day. K E Y W O R D S biological nascent evolution, bone, CARS, collagen, nonlinear optical microscopy, SHG, snail, TPEF

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Impurity Controlled near Infrared Surface Plasmonic in AlN

“…The SPs' materials are widely used in these fields, in which SPs resonance (SPR) is distributed in ultraviolet or visible light regions. For some special applications, such as optical communication, biological detection in vivo, and photon medicine [14,15], SPR in the near-infrared band is more prevalent. However, due to the rapid development of non-linear optics, SPR also plays a very important role in some non-linear optical spectroscopy fields, such as surface-enhanced two-photon excited fluorescence (SE-TPEF) [16][17][18], second harmonic generation (SE-SHG) [19], and coherent anti-Stokes-Raman scattering (SE-CARS) [20].…”

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Photoinduced charge transfer in quasi-one-dimensional polymers in two-photon absorption

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