Multi-scale fractal Fourier Ptychographic microscopy to assess the dose-dependent impact of copper pollution on living diatoms.
Vittorio Bianco, Lisa Miccio, Daniele Pirone, Elena Cavalletti, Jaromir Behal, Pasquale Memmolo, Angela Sardo, Pietro Ferraro
Author Information
Vittorio Bianco: CNR-ISASI, Institute of Applied Sciences and Intelligent Systems "E. Caianiello", Via Campi Flegrei 34, 80078, Pozzuoli, Naples, Italy. vittorio.bianco@isasi.cnr.it. ORCID
Lisa Miccio: CNR-ISASI, Institute of Applied Sciences and Intelligent Systems "E. Caianiello", Via Campi Flegrei 34, 80078, Pozzuoli, Naples, Italy. lisa.miccio@isasi.cnr.it.
Daniele Pirone: CNR-ISASI, Institute of Applied Sciences and Intelligent Systems "E. Caianiello", Via Campi Flegrei 34, 80078, Pozzuoli, Naples, Italy.
Elena Cavalletti: Marine Biotechnology Department, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Naples, Italy.
Jaromir Behal: CNR-ISASI, Institute of Applied Sciences and Intelligent Systems "E. Caianiello", Via Campi Flegrei 34, 80078, Pozzuoli, Naples, Italy. ORCID
Pasquale Memmolo: CNR-ISASI, Institute of Applied Sciences and Intelligent Systems "E. Caianiello", Via Campi Flegrei 34, 80078, Pozzuoli, Naples, Italy.
Angela Sardo: Marine Biotechnology Department, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Naples, Italy.
Pietro Ferraro: CNR-ISASI, Institute of Applied Sciences and Intelligent Systems "E. Caianiello", Via Campi Flegrei 34, 80078, Pozzuoli, Naples, Italy.
Accumulation of bioavailable heavy metals in aquatic environment poses a serious threat to marine communities and human health due to possible trophic transfers through the food chain of toxic, non-degradable, exogenous pollutants. Copper (Cu) is one of the most spread heavy metals in water, and can severely affect primary producers at high doses. Here we show a novel imaging test to assay the dose-dependent effects of Cu on live microalgae identifying stress conditions when they are still capable of sustaining a positive growth. The method relies on Fourier Ptychographic Microscopy (FPM), capable to image large field of view in label-free phase-contrast mode attaining submicron lateral resolution. We uniquely combine FPM with a new multi-scale analysis method based on fractal geometry. The system is able to provide ensemble measurements of thousands of diatoms in the liquid sample simultaneously, while ensuring at same time single-cell imaging and analysis for each diatom. Through new image descriptors, we demonstrate that fractal analysis is suitable for handling the complexity and informative power of such multiscale FPM modality. We successfully tested this new approach by measuring how different concentrations of Cu impact on Skeletonema pseudocostatum diatom populations isolated from the Sarno River mouth.
