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Although polymerase chain reaction (PCR) is the most widely used method for DNA amplification, the requirement of thermocycling limits its non-laboratory applications. Isothermal DNA amplification techniques are hence valuable for on-site diagnostic applications in place of traditional PCR. Here we describe a true isothermal approach for amplifying and detecting double-stranded DNA based on a CRISPR–Cas9-triggered nicking endonuclease-mediated Strand Displacement Amplification method (namely CRISDA). CRISDA takes advantage of the high sensitivity/specificity and unique conformational rearrangements of CRISPR effectors in recognizing the target DNA. In combination with a peptide nucleic acid (PNA) invasion-mediated endpoint measurement, the method exhibits attomolar sensitivity and single-nucleotide specificity in detection of various DNA targets under a complex sample background. Additionally, by integrating the technique with a Cas9-mediated target enrichment approach, CRISDA exhibits sub-attomolar sensitivity. In summary, CRISDA is a powerful isothermal tool for ultrasensitive and specific detection of nucleic acids in point-of-care diagnostics and field analyses. Isothermal DNA amplification techniques are useful for diagnostic applications in place of traditional PCR. Here the authors describe CRISDA, which combines CRISPR–Cas9 with strand displacement amplification and exhibits attomolar sensitivity and single-nucleotide specificity in DNA detection.

Photothermal therapy (PTT) offers many advantages such as high efficiency and minimal invasiveness, but clinical adoption of PTT nanoagents have been stifled by unresolved concerns such as the biodegradability as well as long-term toxicity. Herein, poly (lactic-co-glycolic acid) (PLGA) loaded with black phosphorus quantum dots (BPQDs) is processed by an emulsion method to produce biodegradable BPQDs/PLGA nanospheres. The hydrophobic PLGA not only isolates the interior BPQDs from oxygen and water to enhance the photothermal stability, but also control the degradation rate of the BPQDs. The in vitro and in vivo experiments demonstrate that the BPQDs/PLGA nanospheres have inappreciable toxicity and good biocompatibility, and possess excellent PTT efficiency and tumour targeting ability as evidenced by highly efficient tumour ablation under near infrared (NIR) laser illumination. These BP-based nanospheres combine biodegradability and biocompatibility with high PTT efficiency, thus promising high clinical potential. Black phosphorus is a biodegradable 2D material that has attracted growing interest in biomedicine. Here, the authors carry out in vitro and in vivo experiments to demonstrate that nanospheres loaded with black-phosphorus quantum dots perform as promising phothermal cancer therapy agents.

The treatment of bone defects remains a significant challenge to be solved clinically. Immunomodulatory properties of orthopedic biomaterials have significance in regulating osteoimmune microenvironment for osteogenesis. A lactic acid‐co‐glycolic acid (PLGA) scaffold incorporates black phosphorus (BP) fabricated by 3D printing technology to investigate the effect of BP on osteoimmunomodulation and osteogenesis in site. The PLGA/BP scaffold exhibits suitable biocompatibility, biodegradability, and mechanical properties as an excellent microenvironment to support new bone formation. The studies' result also demonstrate that the PLGA/BP scaffolds are able to recruit and stimulate macrophages M2 polarization, inhibit inflammation, and promote human bone marrow mesenchymal stem cells (hBMSCs) proliferation and differentiation, which in turn promotes bone regeneration in the distal femoral defect region of steroid‐associated osteonecrosis (SAON) rat model. Moreover, it is screened and demonstrated that PLGA/BP scaffolds can promote osteogenic differentiation by transcriptomic analysis, and PLGA/BP scaffolds promote osteogenic differentiation and mineralization by activating PI3K‐AKT signaling pathway in hBMSC cells. In this study, it is shown that the innovative PLGA/BP scaffolds are extremely effective in stimulating bone regeneration by regulating macrophage M2 polarization and a new strategy for the development of biomaterials that can be used to repair bone defects is offered.

Photothermal therapy (PTT) is a fledgling therapeutic strategy for cancer treatment with minimal invasiveness but clinical adoption has been stifled by concerns such as insufficient biodegradability of the PTT agents and lack of an efficient delivery system. Here, black phosphorus (BP) nanosheets are incorporated with a thermosensitive hydrogel [poly(d,l‐lactide)‐poly(ethylene glycol)‐poly(d,l‐lactide) (PDLLA‐PEG‐PDLLA: PLEL)] to produce a new PTT system for postoperative treatment of cancer. The BP@PLEL hydrogel exhibits excellent near infrared (NIR) photothermal performance and a rapid NIR‐induced sol–gel transition as well as good biodegradability and biocompatibility in vitro and in vivo. Based on these merits, an in vivo PTT postoperative treatment strategy is established. Under NIR irradiation, the sprayed BP@PLEL hydrogel enables rapid gelation forming a gelled membrane on wounds and offers high PTT efficacy to eliminate residual tumor tissues after tumor removal surgery. Furthermore, the good photothermal antibacterial performance prevents infection and this efficient and biodegradable PTT system is very promising in postoperative treatment of cancer. A sprayable and biodegradable photothermal therapy (PTT) system composed of a thermosensitive hydrogel incorporated with black phosphorus (BP) nanosheets is presented for post‐surgical treatment of cancer. The obtained hydrogel enables rapid gelation and offers high PTT efficacy to eliminate residual tumor after surgery. This efficient and biodegradable PTT system is very promising in the postoperative treatment of cancer.

A new solar energy storage system is designed and synthesized based on phase‐changing microcapsules incorporated with black phosphorus sheets (BPs). BPs are 2D materials with broad light absorption and high photothermal performance, which are synthesized and covalently modified with poly(methyl methacrylate) (PMMA) to produce the PMMA‐modified BPs (mBPs). With the aid of PMMA, the mBPs and phase‐changing materials (PCM, eicosane) are encapsulated together to form microcapsules. The microencapsulated eicosane and mBPs (mBPs‐MPCM) composites exhibit a high latent heat of over 180 kJ kg−1, good thermal reliability, as well as excellent photothermal characteristics inherited from BPs. Owing to the direct contact in the integrated mBPs‐MPCM composites, the thermal energy generated by mBPs is transferred to eicosane immediately giving rise to three times higher efficiency in solar energy storage compared to microcapsules with mBPs on the surface. The mBPs‐MPCM composites have great potential in solar energy storage applications and the concept of integrating photothermal materials and PCMs as the core provides insights into the design of high‐efficiency solar energy storage materials. Phase‐changing microcapsules incorporated with black phosphorus are designed and prepared for efficient solar energy storage. Because of the direct contact between the black phosphorus sheets and eicosane, the microencapsulated composites show reduced energy loss during solar‐thermal energy transfer and accelerated solar energy storage. This structure has large potential in high‐efficiency solar energy storage.

High performance X-ray detector with ultra-high spatial and temporal resolution are crucial for biomedical imaging. This study reports a dynamic direct-conversion CMOS X-ray detector assembled with screen-printed CsPbBr 3 , whose mobility-lifetime product is 5.2 × 10 −4  cm 2  V –1 and X-ray sensitivity is 1.6 × 10 4  µC Gy air –1  cm –2 . Samples larger than 5 cm × 10 cm can be rapidly imaged by scanning this detector at a speed of 300 frames per second along the vertical and horizontal directions. In comparison to traditional indirect-conversion CMOS X-ray detector, this perovskite CMOS detector offers high spatial resolution (5.0 lp mm −1 ) X-ray radiographic imaging capability at low radiation dose (260 nGy). Moreover, 3D tomographic images of a biological specimen are also successfully reconstructed. These results highlight the perovskite CMOS detector’s potential in high-resolution, large-area, low-dose dynamic biomedical X-ray and CT imaging, as well as in non-destructive X-ray testing and security scanning. Biomedical X-ray imaging requires high spatial and temporal resolution of the detectors. Liu et al. report a screen-printed perovskite direct-conversion X-ray CMOS imager with a spatial resolution of 5 lp mm −1 and a speed of 300 fps for low-dose 2D radiography and 3D computed tomography imaging.

The photochemical activity of black phosphorus (BP) in near‐infrared (NIR) light controlled in situ biomineralization is investigated. Owing to the excellent NIR absorption, irradiation with NIR light not only promotes degradation of BP into PO43−, but also enhances the chemical activity to accelerate the reaction between PO43− and Ca2+ and promote in situ biomineralization. Mineralization of hydrogels is demonstrated by the preparation of BP incorporated hydrogel (BP@Hydrogel) which delivers greatly improved biomineralization performance under NIR illumination. The biomineralization process which can be controlled by modulating the light irradiation time and location has a high potential in controlling the mechanical properties and osteoinductive ability in tissue engineering. This study also provides insights into the degradation, photochemical activity, and new biological/biomedical applications of BP. Photochemical activity of black phosphorus (BP) for controlled in situ biomineralization is investigated. Near infrared (NIR) light can promote the degradation of BP and enhance their chemical activity to accelerate the mineralization process. BP@Hydrogel with NIR irradiation exhibit greatly improved biomineralization and can be controlled by modulating the irradiation time and location, thus promising high potential in bioengineering.

Although nanomaterials have shown promising biomedical application potential, incomplete understanding of their molecular interactions with biological systems prevents their inclusion into mainstream clinical applications. Here we show that black phosphorus (BP) nanomaterials directly affect the cell cycle’s centrosome machinery. BP destabilizes mitotic centrosomes by attenuating the cohesion of pericentriolar material and consequently leads to centrosome fragmentation within mitosis. As a result, BP-treated cells exhibit multipolar spindles and mitotic delay, and ultimately undergo apoptosis. Mechanistically, BP compromises centrosome integrity by deactivating the centrosome kinase polo-like kinase 1 (PLK1). BP directly binds to PLK1, inducing its aggregation, decreasing its cytosolic mobility and eventually restricting its recruitment to centrosomes for activation. With this mechanism, BP nanomaterials show great anticancer potential in tumour xenografted mice. Together, our study reveals a molecular mechanism for the tumoricidal properties of BP and proposes a direction for biomedical application of nanomaterials by exploring their intrinsic bioactivities. Understanding the fundamental nano–bio interactions of nanomaterials intended for biomedical use might unlock potential alternative applications. Here the authors reveal a tumoricidal mechanism of black phosphorus nanomaterials where these nanomaterials directly affect the mitotic centrosome machinery by suppressing polo-like kinase 1, suggesting that nanomaterials can be applied in targeted cancer therapy with their intrinsic nano–bio properties.

An efficient metal‐free photocatalyst composed of black phosphorus (BP) and graphitic carbon nitride (CN) is prepared on a large scale by ball milling. Using economical urea and red phosphorus (RP) as the raw materials, the estimated materials cost of BP/CN is 0.235 Euro per gram. The BP/CN heterostructure shows efficient charge separation and possesses abundant active sites, giving rise to excellent photocatalytic H2 evolution and rhodamine B (RhB) degradation efficiency. Without using a co‐catalyst, the metal‐free BP/CN emits H2 consistently at a rate as large as 786 µmol h−1 g−1 and RhB is decomposed in merely 25 min during visible‐light irradiation. The corresponding electron/hole transfer and catalytic mechanisms are analyzed and described. The efficient metal‐free catalyst is promising in visible‐light photocatalysis and the simple ball‐milling synthetic method can be readily scaled up. Metal‐free black phosphorus/graphitic carbon nitride (BP/CN) heterostructures are prepared by ball milling using economical urea and red phosphorus as the raw materials. Without using a co‐catalyst, BP/CN emits H2 consistently at a rate as large as 786 µmol h−1 g−1 and rhodamine B is decomposed in merely 25 min, demonstrating excellent performances in visible‐light photocatalysis.

Owing to increasing global demand for carbon neutral and fossil‐free energy systems, extensive research is being conducted on efficient and inexpensive electrocatalysts for catalyzing the kinetically sluggish oxygen reduction reaction (ORR) at the cathode of fuel cells. Platinum (Pt)‐based alloys are considered promising candidates for replacing expensive Pt catalysts. However, the current screening process of Pt‐based alloys is time‐consuming and labor‐intensive, and the descriptor for predicting the activity of Pt‐based catalysts is generally inaccurate. This study proposed a strategy by combining high‐throughput first‐principles calculations and machine learning to explore the descriptor used for screening Pt‐based alloy catalysts with high Pt utilization and low Pt consumption. Among the 77 prescreened candidates, we identified 5 potential candidates for catalyzing ORR with low overpotential. Furthermore, during the second and third rounds of active learning, more Pt‐based alloys ORR candidates are identified based on the relationship between structural features of Pt‐based alloys and their activity. In addition, we highlighted the role of structural features in Pt‐based alloys and found that the difference between the electronegativity of Pt and heteroatom, the valence electrons number of the heteroatom, and the ratio of heteroatoms around Pt are the main factors that affect the activity of ORR. More importantly, the combination of those structural features can be used as structural descriptor for predicting the activity of Pt‐based alloys. We believe the findings of this study will provide new insight for predicting ORR activity and contribute to exploring Pt‐based electrocatalysts with high Pt utilization and low Pt consumption experimentally. The current screening process of platinum (Pt)‐based alloys is time‐consuming and labor‐intensive, and the descriptor for predicting the activity is generally inaccurate. This study proposed a strategy by combining high‐throughput first‐principles calculations and machine learning (ML) to explore the structural descriptor used for predicting the activity of Pt‐based alloys and screening Pt‐based alloy catalysts with high Pt utilization and low Pt consumption. We believe the results will provide a useful dataset for experimentalists to further scrutinize the predicted oxygen reduction reaction (ORR) activity as well as for data scientists to construct ML models for ORR performance predictions.