Developing membrane-derived nanocarriers for ex vivo therapy of homologous breast cancer cells

Aim: The primary aim of this study was to develop biomimetic nanocarriers for specific homologous targeting of the anticancer drugs ammonium pyrrolidine dithiocarbamate (PDTC) and doxorubicin. Methods: Membranous nanovesicles were synthesized from a breast cancer cell line (MCF7) by syringe extrusion process and were loaded with PDTC and doxorubicin. Besides their abilities for self-homing, the drug-loaded nanovesicles showed anti-cell proliferative effects via the generation of reactive oxygen species. Results: The nanovesicles demonstrated efficient internalization via homologous targeting. Delivery of PDTC showed a higher killing effect for homologous cell targeting than other cell types. Experimental results demonstrated increased antiproliferative potency of PDTC, which induced apoptosis via reactive oxygen species generation. Conclusion: The developed membrane-derived nanocarrier is an attractive biocompatible system for ex vivo targeted drug delivery.

Ammonium Pyrrolidine Dithiocarbamate-Modified CdTe/CdS Quantum Dots as a Turn-on Fluorescent Sensor for Detection of Trace Cadmium Ions

In this work, ammonium pyrrolidine dithiocarbamate (APDC) was used as a surface etchant to modify CdTe/CdS core-shell quantum dots (QDs). The APDC etchant combines with the cadmium ions (Cd²⁺) on the surface of the QDs, resulting in the formation of surface holes. The formation of these holes changes the QD surface structure, which leads to fluorescence quenching of the QDs. Newly added Cd²⁺ can selectively recognize and combine with these holes; thus, the fluorescence intensity of the QDs can be restored. The linear response of this turn-on fluorescent sensor was found to be 0-100 μg/L and 100-600 μg/L under the determined optimal conditions, and its limit of detection (LOD) for Cd²⁺ was 2.642 μg/L (23.5 nmol/L).

Solid phase extraction for the speciation and preconcentration of inorganic selenium in water samples: a review

Selenium is an essential element for the normal cellular function of living organisms. However, selenium is toxic at concentrations of only three to five times higher than the essential concentration. The inorganic forms (mainly selenite and selenate) present in environmental water generally exhibit higher toxicity (up to 40 times) than organic forms. Therefore, the determination of low levels of different inorganic selenium species in water is an analytical challenge. Solid-phase extraction has been used as a separation and/or preconcentration technique prior to the determination of selenium species due to the need for accurate measurements for Se species in water at extremely low levels. The present paper provides a critical review of the published methods for inorganic selenium speciation in water samples using solid phase extraction as a preconcentration procedure. On the basis of more than 75 references, the different speciation strategies used for this task have been highlighted and classified. The solid-phase extraction sorbents and the performance and analytical characteristics of the developed methods for Se speciation are also discussed.