Methods (approaches) for selective staining / contrasting of cells and tissues have been proposed for not “chemical”, but “physical” multiplexing in fluorescent and other types of visualization

Methods (approaches) for selective staining / contrasting of cells and tissues have been proposed for not “chemical”, but “physical” multiplexing in fluorescent and other types of visualization, i.e. development of the visualization methods for the distribution of physical descriptors in a cell or tissue culture or tissue slice (e.g., in a living brain slice) based on either direct or indirect binding by the cellular structures of the agents that act not as conventional fluorescent dyes, but as the indicators of the structure’s response to a non-optical signal (for example, dispersed scintillators, some semiconductors or magnetic particles). Measurements using such disperse systems become widely available, more compact and more informative when they are implemented on lensless microscopes based on the CMOS sensors. This approach was shown to be particularly effective during working with tetrapyrrole dyes. In our works, primary data were obtained on the effect of the medium parameters (the solvent polarity, acidity, ionic strength, etc.) on the photophysical properties and photochemical activity of a number of tetrapyrrolic compounds. A clear spectral response in the form of a bathochromic or hypsochromic shifts or a change in the absorption and fluorescence intensity of the dyes makes it possible to implement such measurements on a chip in order to design a series of compact detecting devices for diagnostic and research purposes.

Gradov O.V. (2016). Multiparametric lab-on-a-chip for biochemical and physico-chemical measurements with reference to the coordinates of the mapped sample. In Proc. Conference and Exhibition «Scientific Instrumentation — current state and prospects», p. 183–185 (in Russian).

Gradov O.V., Jablokov A.G. (2016). Novel morphometrics-on-a-chip: CCD- or CMOS-lab-on-achip based on discrete converters of different physical and chemical parameters of histological samples into the optical signals with positional sensitivity for morphometry of non-optical patterns. Journal of Biomedical Technologies, (2):1–29.

New sources (upd.: Sept. 2024):

Gradov, O. (2024). Multispectral lens-less microscopes and optofluidic chip readers with discrete convertors of chemical and non-optical physical signals into spectrozonal optical ones as novel instruments for medical ecology, biodiagnostics, and material quality control. Proceedings of SPIE — The International Society for Optical Engineering, 13279:1327920. DOI: 10.1117/12.3041309