مطالعه پروتئين EGFP الحاق شده به پپتيد B72 با هدف محاسبه بازده كوانتومي آن

Green fluorescent protein (GFP) is a natural protein widely used in biological research due to its fluorescence capabilities. The optimized version of GFP, known as enhanced green fluorescent protein (EGFP), is employed in biological studies, cellular imaging, and the design of biosensors due to its higher fluorescence production and greater stability. The B72 peptide is specifically designed to bind to GM1 ganglioside receptors and plays an important role in identifying specific cells, as well as serving as a target molecule in biosensors. Quantum yield is a key parameter in eva‎luating the efficiency of fluorescent molecules, representing the ratio of emitted photons to absorbed photons. The higher this ratio, the more efficiently a fluorescent molecule produces light after absorbing energy, leading to improved performance in applications such as biological imaging and molecular detection. High quantum yield in biosensors enhances the sensitivity and accuracy of target molecule detection. In this study, after the expression and purification of EGFP and EGFP-B72 proteins, the absorption and emission of the samples, as well as the standard (FITC), were measured using a multimode reader in a 96-well plate at different concentrations. Quantum yield was calculated by comparing the protein samples with FITC. This study aimed to eva‎luate the effect of attaching the B72 peptide to EGFP on its optical properties, particularly its quantum yield. The results showed that the attachment of the B72 peptide to EGFP only led to a slight increase in quantum yield from 0.47 to 0.49. These minor changes are likely due to the absence of significant structural alterations in the protein, indicating that the attachment of the peptide does not have a significant impact on the optical properties of the protein.

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