Formation Mechanism Of Layer-Structured Nanocrystals And Application Of Nanoparticles In The Detection Of Histamine

Sonication and centrifugation of two-dimensional Layer-Structured nanosheets have been widely used to produce various layer-structured nanocrystals,but the formation mechanism is not yet clear.A general understanding is that the formation of nanocrystals is due to the splitting of crystalline sheets under sonication/centrifugation.At the same time,for galaxies,including our galaxy,their formation process can be described simply as follows:There is a large number of disorderly cold gas in the galaxy.The kinematic and radiative feedback from existing stars continuously injects energy into the gas,producing shock waves propagating across the gas cloud and creating density enhancements that may make the gas cloud further collapse under its own gravity to form dense clumps to breed new stars.This process of galaxy formation can be described by the continuity equation and the momentum equation,and the density probability distribution function obeys the lognormal distribution.Here we experimentally show that high-speed rotation of amorphous black phosphorus ultrathin film can lead to the regulated formation of massive nanocrystals confined in the spatial region of the original film.The probable sizes of these nanocrystals are several nanometers depending on the rotation speed.Their volumes show a clear log-normal distribution having a line-width increase with rotation speed.This phenomenon is similar to the density probability distribution of galaxies.By means of the above galaxy formation mechanism and to demonstrate possible formation processes of LSNCs.In this work,we reveal that the physical mechanisms leading to formation of nanocrystals can be compared to formation of galaxies,and creates a test bed for the study of galaxies under different formation conditions.Nanoparticles are also applied to surface-enhanced Raman scattering(SERS).Histamine is a kind of biogenic amine which was widely found in plants and animals.Therefore,histamine detection method is particularly important in medicine.The use of SERS to detect histamine concentration is fast,simple,and low cost,but the accuracy can’t meet the medical requirements.Our study found that histamine’s low-frequency Raman signal is much stronger than high-frequency Raman signal,while the existing SERS methods to detect histamine concentration are mainly using high-frequency Raman signal.Therefore,detection of histamine by low-frequency Raman scattering will greatly improve the detection limit of histamine concentration detected by SERS methods in serum testing.