An analysis system (100, 500) comprising: a photolysis zone, a sample introduction system configured to provide intact biological entities to the photolysis zone, the biological entities being isolated from each other in a focused sheath flow; a photolysis light source configured to generate light to generate hydroxide radicals within the photolysis zone from a source of hydroxide radicals; the photolysis zone being configured to receive the sheath flow including the biological entities and the light of the photolysis light source so as to oxidize a dosimeter internal standard and so as to oxidize biological compounds of the biological entities in vivo, a radical dosimeter comprising a dosimetry zone and a fluorescence/emission photodetector, wherein the dosimetry zone is configured to receive the biological entities from the photolysis zone, and wherein the fluorescence/ emission photodetector is configured to detect oxidation of the dosimeter internal standard, resulting from reaction of the dosimeter internal standard and the hydroxide radicals, within the dosimetry zone; control logic (105, 106) configured to determine based on the detected oxidation of the dosimeter internal standard if a target concentration of hydroxide radicals was generated for each of the biological entities and, when it is determined that the target concentration of hydroxide radicals was not generated for each of the biological entities, to control the sample introduction system and/or the photolysis light source to adjust conditions of the photolysis zone to meet the target concentration of hydroxide radicals; and a reservoir configured to receive the biological entities including the oxidized biological compounds, characterized in that the radical dosimeter further comprises a scattered light detector, wherein the scattered light detector is configured to detect presence of the biological entities within the dosimetry zone. a photolysis zone, a sample introduction system configured to provide intact biological entities to the photolysis zone, the biological entities being isolated from each other in a focused sheath flow; a photolysis light source configured to generate light to generate hydroxide radicals within the photolysis zone from a source of hydroxide radicals; the photolysis zone being configured to receive the sheath flow including the biological entities and the light of the photolysis light source so as to oxidize a dosimeter internal standard and so as to oxidize biological compounds of the biological entities in vivo, a radical dosimeter comprising a dosimetry zone and a fluorescence/emission photodetector, wherein the dosimetry zone is configured to receive the biological entities from the photolysis zone, and wherein the fluorescence/ emission photodetector is configured to detect oxidation of the dosimeter internal standard, resulting from reaction of the dosimeter internal standard and the hydroxide radicals, within the dosimetry zone; control logic (105, 106) configured to determine based on the detected oxidation of the dosimeter internal standard if a target concentration of hydroxide radicals was generated for each of the biological entities and, when it is determined that the target concentration of hydroxide radicals was not generated for each of the biological entities, to control the sample introduction system and/or the photolysis light source to adjust conditions of the photolysis zone to meet the target concentration of hydroxide radicals; and a reservoir configured to receive the biological entities including the oxidized biological compounds, characterized in that the radical dosimeter further comprises a scattered light detector, wherein the scattered light detector is configured to detect presence of the biological entities within the dosimetry zone.