Na, Yu-Ran Kim, So Yeon Gaublomme, Jellert T. Shalek, Alex K. Jorgolli, Marsela Park, Hongkun Yang, Eun Gyeong 2024-01-20T13:04:47Z 2024-01-20T13:04:47Z 2021-09-01 2013-01 1530-6984 https://pubs.kist.re.kr/handle/201004/128511 Developing a detailed understanding of enzyme function in the context of an intracellular signal transduction pathway requires minimally invasive methods for probing enzyme activity in situ. Here, we describe a new method for monitoring enzyme activity in living cells by sandwiching live cells between two vertical silicon nanowire (NW) arrays. Specifically, we use the first NW array to immobilize the cells and then present enzymatic substrates intracellularly via the second NW array by utilizing the NWs' ability to penetrate cellular membranes without affecting cells' viability or function. This strategy, when coupled with fluorescence microscopy and mass spectrometry, enables intracellular examination of protease, phosphatase, and protein kinase activities, demonstrating the assay's potential in uncovering the physiological roles of various enzymes. English AMER CHEMICAL SOC RESONANCE ENERGY-TRANSFER ACTIVITY-BASED PROBES MASS-SPECTROMETRY FLUORESCENT-PROBES CASPASE ACTIVITIES SILICON NANOWIRES PROTEIN-KINASES SUBSTRATE BIOSENSORS DIFFERENTIATION Probing Enzymatic Activity inside Living Cells Using a Nanowire-Cell "Sandwich" Assay Article 10.1021/nl3037068 1 NANO LETTERS, v.13, no.1, pp.153 - 158 NANO LETTERS 13 1 153 158 scie scopus 000313142300028 2-s2.0-84872116038 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article RESONANCE ENERGY-TRANSFER ACTIVITY-BASED PROBES MASS-SPECTROMETRY FLUORESCENT-PROBES CASPASE ACTIVITIES SILICON NANOWIRES PROTEIN-KINASES SUBSTRATE BIOSENSORS DIFFERENTIATION Silicon nanowire sandwich assembly live cell assay enzyme activity