Dynamic anti-counterfeiting and information encryption of Sr3Y2Ge3O12: Tb3+, Er3+ phosphor via carriers filling and release processes.

Complex and high-security-level anti-counterfeiting strategies with multiple luminescent modes are extremely critical for meeting the requirement of constantly developing information storage and information security. In this work, Tb3+ ions doped Sr3Y2Ge3O12 (SYGO) and Tb3+/Er3+ co-doped SYGO phosphors are successfully fabricated and are unitized for anti-counterfeiting and information encoding under distinct stimuli sources. The green photoluminescence (PL), long persistent luminescence (LPL), mechano-luminescence (ML), and photo-stimulated luminescence (PSL) behaviors are respectively observed under the stimuli of ultraviolet (UV), thermal disturbance, stress, and 980 nm diode laser. Based on the time-dependence of the filling and releasing rate of the carriers from the shallow traps, the dynamic information encryption strategy is proposed by simply changing the UV pre-irradiation time or shut-off time. Moreover, a tunable color from green to red is realized by prolonging the 980 nm laser irradiation time, which is attributed to the elaborate cooperation of the PSL and upconversion (UC) behaviors. The anti-counterfeiting method based on SYGO: Tb3+ and SYGO: Tb3+, Er3+ phosphors herein possess an extremely high-security level with attractive performance for designing advanced anti-counterfeiting technology.

FACS-iChip: a high-efficiency iChip system for microbial 'dark matter' mining.

The isolation chip method (iChip) provides a novel approach for culturing previously uncultivable microorganisms; this method is currently limited by the user being unable to ensure single-cell loading within individual wells. To address this limitation, we integrated flow cytometry-based fluorescence-activated cell sorting with a modified iChip (FACS-iChip) to effectively mine microbial dark matter in soils. This method was used for paddy soils with the aim of mining uncultivable microorganisms and making preliminary comparisons between the cultured microorganisms and the bulk soil via 16S rRNA gene sequencing. Results showed that the FACS-iChip achieved a culture recovery rate of almost 40% and a culture retrieval rate of 25%. Although nearly 500 strains were cultured from 19 genera with 8 FACS-iChip plates, only six genera could be identified via 16S rRNA gene amplification. This result suggests that the FACS-iChip is capable of detecting strains in the currently dead spaces of PCR-based sequencing technology. We, therefore, conclude that the FACS-iChip system provides a highly efficient and readily available approach for microbial 'dark matter' mining.

Correction to: FACS­iChip: a high­efficiency iChip system for microbial 'dark matter' mining.

[This corrects the article DOI: 10.1007/s42995-020-00067-7.].