Patent ID: 9222074
Filing Date: 2015-12-29
Classification: C12N,C12Q,G01N

Abstract:
1. Process for producing a three-dimensional tissue by introducing eukaryotic cells into a matrix and cultivating the cells within the matrix in a cell culture medium within a cell culture vessel while determining the dissolved oxygen concentration by measuring the emission from an oxygen-sensitive dye which is phosphorescing upon irradiation of an excitation wavelength, the process comprising integrating a support into the matrix, the support being particulate and permeable for oxygen and containing in its inner volume the oxygen-sensitive dye, directing an irradiation onto the matrix, the irradiation having an excitation wavelength suitable for exciting emission from the oxygen-sensitive dye, wherein the irradiation having the excitation wavelength is intensity-modulated to at least two frequencies, measuring the emission from the support containing the oxygen-sensitive dye, and detecting the time-resolved intensity of radiation emitted by the dye, wherein the phase-shift of the emission is determined from the emission for each of the at least two frequencies and determining the decay time of the phosphorescence of the oxygen-sensitive dye from the phase-shift, and wherein the irradiation and emission are selected and the matrix is configured such that the irradiation and emission at least partially cross a volume portion of the matrix to measure at a depth of at least 5-12 mm in the matrix.