pH-responsive polymer microcapsules for targeted delivery of biomaterials to the midgut of Drosophila suzukii
Fig 7
In vivo release of FITC-dextran triggered by pH changes in D. suzukii gut.
In vivo release of FITC-dextran from not from control non–responsive PMMA (a-c), but pH-responsive P2VP (d-f) microcapsules fed to D. suzukii adults. Intact fluorescent PMMA microcapsules in the crop (a), excrement (b) and the lumen of the midgut (c). Intact pH-responsive P2VP microcapsules in the crop (d), but none in the excrement (e) and midgut (f). Dispersed fluorescence in the posterior midgut shows that the P2VP microcapsules have released their contents. Fluorescence was also seen in the haemolymph released from the body during dissection. Strong fluorescence accumulated in the Malpighian tubules (Mt) demonstrating uptake of FITC-dextran from the haemolymph. All scale bars 200 μm. (g) Fluorescence in the extracted haemolymph of flies fed normal diet (control), normal diet with PMMA non-responsive microcapsules and normal diet with P2VP pH-responsive microcapsules (mean±s.e.m; n = 3). The fluorescence is significantly more intense in the haemolymph of flies fed responsive P2VP microcapsules compared to the control and non-responsive PMMA microcapsules (P = 0.0004).