To overcome the low efficiency of conventional confocal Raman spectroscopy, many efforts have been devoted to parallelizing the Raman excitation and acquisition, in which the scattering from multiple foci is projected onto different locations on a spectrometer’s CCD, along either its vertical, horizontal dimension, or even both. While the latter projection scheme relieves the limitation on the row numbers of the CCD, the spectra of multiple foci are recorded in one spectral channel, resulting in spectral overlapping. Here, we developed a method under a compressive sensing framework to demultiplex the superimposed spectra of multiple cells during their dynamic processes. Unlike the previous methods which ignore the information connection between the spectra of the cells recorded at different time, the proposed method utilizes a prior that a cell’s spectra acquired at different time have the same sparsity structure in their principal components. Rather than independently demultiplexing the mixed spectra at the individual time intervals, the method demultiplexes the whole spectral sequence acquired continuously during the dynamic process. By penalizing the sparsity combined from all time intervals, the collaborative optimization of the inversion problem gave more accurate recovery results. The performances of the method were substantiated by a 1D Raman tweezers array, which monitored the germination of multiple bacterial spores. The method can be extended to the monitoring of many living cells randomly scattering on a coverslip, and has a potential to improve the throughput by a few orders.

中文翻译：

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多焦点拉曼光谱和压缩传感相结合，用于并行监测单细胞动力学

为了克服传统共焦拉曼光谱的低效率，许多努力致力于并行拉曼激发和采集，其中来自多个焦点的散射被投射到光谱仪 CCD 上的不同位置，沿其垂直、水平尺寸或甚至两者。虽然后一种投影方案缓解了对CCD行数的限制，但多个焦点的光谱记录在一个光谱通道中，导致光谱重叠。在这里，我们开发了一种在压缩传感框架下的方法，用于在多个细胞的动态过程中解复用多个细胞的叠加光谱。与以往忽略不同时间记录的细胞光谱之间信息联系的方法不同，所提出的方法利用了一个先验，即在不同时间获得的细胞光谱在其主成分中具有相同的稀疏结构。该方法不是在各个时间间隔独立解复用混合光谱，而是解复用在动态过程中连续获取的整个光谱序列。通过惩罚所有时间间隔组合的稀疏性，反演问题的协同优化给出了更准确的恢复结果。该方法的性能由一维拉曼镊子阵列证实，该阵列监测多个细菌孢子的萌发。该方法可以扩展到监测许多随机散布在盖玻片上的活细胞，并有可能将吞吐量提高几个数量级。