China 
Africa 
Explore chapters and articles related to this topic
Optics of Biomedical Instrumentation
Published in Daniel Malacara-Hernández, Brian J. Thompson, Advanced Optical Instruments and Techniques, 2017
Shaun Pacheco, Zhenyue Chen, Rongguang Liang
Basically, there are two types of fluorescence: intrinsic fluorescence (also called autofluorescence and endogenous fluorescence) and extrinsic fluorescence (also called exogenous fluorescence). Autofluorescence emission, arising from intrinsic fluorophores, is an intrinsic property of cells, while extrinsic fluorescence is obtained by adding exogenous fluorophores, such as FITC, GFP, and PE. The exogenous fluorophore offers an alternative for fluorescence imaging. It is a molecule that is naturally occurring or specially designed and can be used as a probe to label cells or tissues. Probes can be designed to localize the tissues, cells, or proteins within a cell, as well as to respond to a specific stimulus and to monitor the production of a gene product. Fluorophores can be bound to an antibody for delivery to specific targets. Green fluorescence protein (GFP), red fluorescence protein (RFP), and rhodamine are some examples of naturally occurring fluorophore proteins that emit fluorescence light in the green or red wavelengths.
Analytics and virus production processes
Published in Amine Kamen, Laura Cervera, Bioprocessing of Viral Vaccines, 2023
Transducing units correspond to the number of viral particles capable to transfer a gene of interest into a cell. This is commonly evaluated using a reporter gene as fluorescent GFP or RFP proteins. Transducing particles could either be quantified with an assay adapted from the TCID50 assay presented previously, or with flow cytometry. Indeed, the principle of applying the suspension of virus onto a cell culture is maintained and the read-out is no longer the cytopathic effect of the suspension but the expression of the reporter gene. Positive wells are then numbered based on the presence or absence of fluorescent gene expression.
Design of artificial cells: artificial biochemical systems, their thermodynamics and kinetics properties
Published in Egyptian Journal of Basic and Applied Sciences, 2022
Adamu Yunusa Ugya, Lin Pohan, Qifeng Wang, Kamel Meguellati
Therefore, the minimal representations of synthetic cellularity using biological processes generated by bottom-up strategies are generating a growing interest in the field of synthetic biology. The use and development of in vitro gene expression systems (IVGES) is considered an advance in photocell engineering to provide off-line biological content for storage and processing in synthetic cell-free environments. Tang group used carboxymethyl-dextran/polylysine (CM-dextran/PLys) coacervate for the sequestration and retention of a plasmid-containing IVGES to show cell-free gene expression and folding of the red fluorescent protein mCherry at pH = 8 [30]. Another study on engineered cells in mammalian tissues is linked to a synthetic module (photoactivated synthesis of cyclic dimeric GMP) to obtain a 40-fold photoactivation of gene expression [36] (Figure 3). Recently, it was found that the oxygenation of stem cells is stimulated by artificial membrane-binding proteins during the engineering of large cartilage tissues [37]. It was reported in 1997 that the vesicle growth was driven by the simple dipeptide catalyst seryl-histidine (Ser-His) through the catalytic synthesis of a hydrophobic dipeptide, N-acteyl-L-phenylalanine-leucinamide (AcPheLeuNH2) [38].