Interaction of TGA@CdTe Quantum Dots with an Extracellular Matrix of Haematococcus pluvialis Microalgae Detected Using Surface-Enhanced Raman Spectroscopy (SERS).

The present study reports the localization and interaction of thioglycolic acid (TGA) capped CdTe quantum dots (TGA@CdTe QDs) within the extracellular matrix (ECM) of Haematococcus pluvialis (Chlorophyceae) microalgae (HPM) after an incubation period of 5 min. Changes in the Raman spectrum of HPM induced by the adsorption of the TGA@CdTe QDs are successfully found by using naked gold anisotropic structures as nano-sensors for surface-enhanced Raman scattering (SERS effect). Raman spectroscopy results show that TGA@CdTe QDs interact with the biomolecules present in the ECM. Sample preparation and characterization by complementary techniques such as confocal and electron microscopy are also used to confirm the presence and localization of the nanoparticles in the algae. This research shows new evidence on early accumulation of QDs in plant cells and would further improve our understanding about their environmental impact.