6 research outputs found
Efficient Direct X‑ray Detection and Imaging Based on a Lead-Free Electron Donor–Acceptor MOF
Metal–organic frameworks (MOFs) have recently
gained extensive
attention as potential materials for direct radiation detection due
to their strong radiation absorption, long-range order, and chemical
tunability. However, it remains challenging to develop a practical
MOF-based X-ray direct detector that possesses high X-ray detection
efficiency, radiation stability, and environmental friendliness. The
integration of donor–acceptor (D–A) pairs into crystalline
MOFs is a powerful strategy for the precise fabrication of multifunctional
materials with unique optoelectronic properties. Herein, a new lead-free
MOF, Cu2I2(TPPA) (CuI-TPPA, TPPA
= tris[4-(pyridine-4-yl)phenyl]amine), with a 6-fold interpenetrated
structure is designed and synthesized based on the electron donor–acceptor
strategy. CuI-TPPA has a large mobility-lifetime (μτ) product of 5.8 × 10–4 cm2 V–1 and a high detection sensitivity
of 73.1 μC Gyair–1 cm–2, surpassing that of commercial α-Se detectors.
Moreover, the detector remains fairly stable with only a 2% reduction
in photocurrent under continuous bias irradiation conditions with
a total dose of over 42.83 Gyair. The CuI-TPPA/poly(vinylidene fluoride) flexible composite X-ray detector films
are successfully manufactured with different thicknesses. Through
multifaceted assessments, the optimal thickness is found with a high
detection sensitivity of up to 143.6 μC Gyair–1 cm–2. As proof-of-concept, 11 ×
9 pixelated X-ray detectors are fabricated on the same composite film
to realize X-ray direct imaging. This work opens up potential applications
of MOFs in environmentally friendly and wearable devices for direct
X-ray detection and imaging
Efficient Direct X‑ray Detection and Imaging Based on a Lead-Free Electron Donor–Acceptor MOF
Metal–organic frameworks (MOFs) have recently
gained extensive
attention as potential materials for direct radiation detection due
to their strong radiation absorption, long-range order, and chemical
tunability. However, it remains challenging to develop a practical
MOF-based X-ray direct detector that possesses high X-ray detection
efficiency, radiation stability, and environmental friendliness. The
integration of donor–acceptor (D–A) pairs into crystalline
MOFs is a powerful strategy for the precise fabrication of multifunctional
materials with unique optoelectronic properties. Herein, a new lead-free
MOF, Cu2I2(TPPA) (CuI-TPPA, TPPA
= tris[4-(pyridine-4-yl)phenyl]amine), with a 6-fold interpenetrated
structure is designed and synthesized based on the electron donor–acceptor
strategy. CuI-TPPA has a large mobility-lifetime (μτ) product of 5.8 × 10–4 cm2 V–1 and a high detection sensitivity
of 73.1 μC Gyair–1 cm–2, surpassing that of commercial α-Se detectors.
Moreover, the detector remains fairly stable with only a 2% reduction
in photocurrent under continuous bias irradiation conditions with
a total dose of over 42.83 Gyair. The CuI-TPPA/poly(vinylidene fluoride) flexible composite X-ray detector films
are successfully manufactured with different thicknesses. Through
multifaceted assessments, the optimal thickness is found with a high
detection sensitivity of up to 143.6 μC Gyair–1 cm–2. As proof-of-concept, 11 ×
9 pixelated X-ray detectors are fabricated on the same composite film
to realize X-ray direct imaging. This work opens up potential applications
of MOFs in environmentally friendly and wearable devices for direct
X-ray detection and imaging
Hypoxia causes trophoblast cell ferroptosis to induce miscarriage through lnc-HZ06/HIF1α-SUMO/NCOA4 axis
Defects of human trophoblast cells may induce miscarriage (abnormal early embryo loss), which is generally regulated by lncRNAs. Ferroptosis is a newly identified iron-dependent programmed cell death. Hypoxia is an important and unavoidable feature in mammalian cells. However, whether hypoxia might induce trophoblast cell ferroptosis and then induce miscarriage, as well as regulated by a lncRNA, was completely unknown. In this work, we discovered at the first time that hypoxia could result in ferroptosis of human trophoblast cells and then induce miscarriage. We also identified a novel lncRNA (lnc-HZ06) that simultaneously regulated hypoxia (indicated by HIF1α protein), ferroptosis, and miscarriage. In mechanism, HIF1α-SUMO, instead of HIF1α itself, primarily acted as a transcription factor to promote the transcription of NCOA4 (ferroptosis indicator) in hypoxic trophoblast cells. Lnc-HZ06 promoted the SUMOylation of HIF1α by suppressing SENP1-mediated deSUMOylation. HIF1α-SUMO also acted as a transcription factor to promote lnc-HZ06 transcription. Thus, both lnc-HZ06 and HIF1α-SUMO formed a positive auto-regulatory feedback loop. This loop was up-regulated in hypoxic trophoblast cells, in RM villous tissues, and in placental tissues of hypoxia-treated mice, which further induced ferroptosis and miscarriage by up-regulating HIF1α-SUMO-mediated NCOA4 transcription. Furthermore, knockdown of either murine lnc-hz06 or Ncoa4 could efficiently suppress ferroptosis and alleviate miscarriage in hypoxic mouse model. Taken together, this study provided new insights in understanding the regulatory roles of lnc-HZ06/HIF1α-SUMO/NCOA4 axis among hypoxia, ferroptosis, and miscarriage, and also offered an effective approach for treatment against miscarriage