Metal-phenolic network as precursor complex coating for forward osmosis membrane with enhanced antifouling property.

In this study, a multi-functional layer was developed based on the commercially available cellulose triacetate (CTA) forward osmosis (FO) membrane to improve its antifouling property. Tannic acid/ferric ion (TA/Fe3+) complexes were firstly coated as a precursor layer on the membrane surface via self-assembly. Afterwards, the tannic acid/diethylenetriamine (TA/DETA) hydrophilic functional layer was further coated, following Ag/polyvinylpyrrolidone (PVP) anti-bacterial layer was formed in situ through the reducibility of TA to obtain TA/Fe3+-TA/DETA-Ag/PVP-modified membrane. The optimized precursor layer was acquired by adjusting the buffer solution pH to 8, TA/Fe3+ ratio to 4 and the number of self-assembled layers to 5. The permeability testing results illustrated that the functional layer had an insignificant effect on the membrane transport parameters. The TA/Fe3+-TA/DETA-Ag/PVP-modified membrane simultaneously exhibited excellent physical and chemical stability. The coated membrane also demonstrated enhanced anti-bacterial properties, achieving 98.63 and 97.30% inhibition against Staphylococcus aureus and Escherichia coli, respectively. Furthermore, the dynamic fouling experiment showed a 12% higher water flux decrease for the TA/Fe3+-TA/DETA-Ag/PVP CTA membrane compared to the nascent CTA membrane, which proved its excellent antifouling performance. This work provides a feasible strategy to heighten the antifouling property of the CTA FO membrane.

Improving antifouling performance of FO membrane by surface immobilization of silver nanoparticles based on a tannic acid: diethylenetriamine precursor layer for municipal wastewater treatment.

In this study, a facile method for multifunctional surface modification on forward osmosis (FO) membrane was constructed by surface immobilization of AgNPs based on tannic acid (TA)/diethylenetriamine (DETA) precursor layer. The cellulose triacetate (CTA) FO membranes modified by TA and DETA with different co-deposition time (6 h, 12 h, 24 h) were investigated. Results indicated that the TA/DETA (24)-Ag CTA membrane with a TA/DETA co-deposition time of 24 h was identified to be optimal, which attained more hydrophilic. And it had the bacterial mortality of Escherichia coli and Staphylococcus aureus reaching 98.23% and 99.83% respectively and possessed excellent physical and chemical binding stability. Meanwhile, the coating layer resulted in the antifouling ability without damaging the membrane intrinsic transport characteristics. As for synthetic municipal wastewater treatment, the water flux of CTA FO membrane decreased approximately 49% of the initial flux after running for 14 days. In contrast, the flux decline rate of TA/DETA (24)-Ag CTA membrane was about 37%. Furthermore, less foulant deposition and higher recovery rate of water flux was observed for TA/DETA (24)-Ag CTA membrane, implying that the modified membrane effectively alleviated membrane fouling and processed a lower flux decline during municipal wastewater treatment. It was attributed to the enhanced surface hydrophilicity and antibacterial property of the coating layer, which improved antifouling property.

Dual-signaling and ultrasensitive detection for PCT based on the photoelectric and electrocatalytic hydrogen evolution signals of Pt/Mo-CoFeS.

Few study has been carried out on the construction of immunesensors utilized the photoelectric and catalytic signal of nanomaterial. Here, a dual-signal electrochemical immunosensor was constructed for procalcitonin (PCT) detection based on the excellent photoelectric and hydrogen evolution performance of molybdenum-doped cobalt-iron sulfur nanosheets modified by platinum nanoparticles (Pt/Mo-CoFeS). Due to the electronic structure regulation between Pt and Mo-CoFeS, Pt/Mo-CoFeS exhibits superior photoelectric and hydrogen evolution performance compared to single Mo-CoFeS, which improved the sensitivity of the electrochemical immunosensor. Furthermore, the presence of Pt improves surface area and biocompatibility, achieving more antibodies loading and signal amplification. The linear range of PCT detection are 0.002-20 ng mL-1 and 0.002-50 ng mL-1, the detection limits are 0.0015 and 0.0012 ng mL-1. In addition, this electrochemical immunosensor was applied to the PCT analysis in human serum samples with high recoveries. F-test and t-test show that there is no significant difference in the test results between the HER and photoelectric signals, the mutual verification between above two signals can effectively improve the accuracy of detection result.

Compressive sensing of ultrasonic array data with full matrix capture in nozzle welds inspection.

The phased array ultrasonic technique (PAUT) with full matrix capture (FMC) exhibits the advantages of high imaging accuracy and great defect characterization ability, which play important roles in the nondestructive testing of welded structures. To address the problem of a large amount of signal acquisition, storage, and transmission data in nozzle weld defect monitoring, a PAUT with an FMC data compression method based on compressive sensing (CS) was proposed. To accomplish this, the detection of nozzle welds using PAUT with FMC was performed by simulation and experiment, and the obtained FMC data were compressed and reconstructed. A suitable sparse representation was found dedicated to the FMC data of nozzle welds, and the reconstruction performance was compared between the greedy theory-based orthogonal matching pursuit (OMP) algorithm and the convex optimization theory-based basis pursuit (BP). Also, an empirical mode decomposition (EMD)-based intrinsic mode function (IMF) circular matrix was constructed to provide another idea for the construction of the sensing matrix. Although the experimental results were not able to reach the ideal effect in the simulation, the image was restored accurately with a small number of measured values, and flaw identification could be guaranteed, indicating that the CS algorithm can effectively improve the defect detection efficiency of the phased array.

Interferometric fiber-optic gyroscope based on mode-division multiplexing.

The interferometric fiber-optic gyroscope (IFOG) is widely used in the fields of inertial navigation and rotational seismology. A direct way to improve the sensitivity of the IFOG is to increase the length of the sensing fiber, but this increases the cost and size of the gyroscope. Here, we propose an IFOG based on mode-division multiplexing (MDM), which exhibits relatively high performance. The experimental results show that, the proposed IFOG is improved to twice as much in terms of sensitivity, angle random walk, and bias instability with the use of MDM. This research provides a novel, to the best of our knowledge, solution for the design and implementation of low-cost, high-sensitivity IFOGs, which could contribute to their application in a wider range of fields.

Dual-polarization interferometric fiber optic gyroscope based on a four-port circulator.

The dual-polarization interferometric fiber optic gyroscope (IFOG) has been studied for many years and achieved remarkable performance. In this study, we propose a novel dual-polarization IFOG configuration based on a four-port circulator, in which the polarization coupling errors and the excess relative intensity noise are well handled meanwhile. Experimental measurements of the short-term sensitivity and long-term drift using a fiber coil with a length of 2 km and a diameter of 14 cm show that the angle random walk of 5.0×10-5∘/h and bias instability of 9.0 × 10-5 °/h are achieved. Moreover, the root power spectrum density of 20n r a d/s/H z is almost flat from 0.001 Hz to 30 Hz. We believe this dual-polarization IFOG is a preferred candidate for the reference-grade performance IFOG.

Different methods of vaginal preparation before cesarean delivery to prevent postoperative infection: a systematic review and network meta-analysis.

OBJECTIVE: Precesarean vaginal antisepsis can benefit pregnant women with ruptured membranes. However, in the general population, recent trials have shown mixed results in reducing postoperative infections. This study aimed to systematically review clinical trials and summarize the most suitable vaginal preparations for cesarean delivery in preventing postoperative infection. DATA SOURCES: We searched PubMed, Web of Science, Cochrane Library, SinoMed databases, and the ClinicalTrials.gov clinical trials registry for randomized controlled trials and conference presentations (past 20 years, 2003-2022). Reference lists of previous meta-analyses were searched manually. In addition, we conducted subgroup analysis on the basis of whether the studies were conducted in developed or developing countries, whether the membranes were ruptured, and whether patients were in labor. STUDY ELIGIBILITY CRITERIA: We included randomized controlled trials comparing vaginal preparation methods for the prevention of postcesarean infection with each other or with negative controls. METHODS: Two reviewers independently extracted data and assessed the risk of bias and the certainty of the evidence. The effectiveness of prevention strategies was assessed by frequentist-based network meta-analysis models. The outcomes were endometritis, postoperative fever, and wound infection. RESULTS: A total of 23 trials including 10,026 cesarean delivery patients were included in this study. Vaginal preparation methods included 19 iodine-based disinfectants (1%, 5%, and 10% povidone-iodine; 0.4% and 0.5% iodophor) and 4 guanidine-based disinfectants (0.05% and 0.20% chlorhexidine acetate; 1% and 4% chlorhexidine gluconate). Overall, vaginal preparation significantly reduced the risks of endometritis (3.4% vs 8.1%; risk ratio, 0.41 [0.32-0.52]), postoperative fever (7.1% vs 11.4%; risk ratio, 0.58 [0.45-0.74]), and wound infection (4.1% vs 5.4%; risk ratio, 0.73 [0.59-0.90]). With regard to disinfectant type, iodine-based disinfectants (risk ratio, 0.45 [0.35-0.57]) and guanidine-based disinfectants (risk ratio, 0.22 [0.12-0.40]) significantly reduced the risk of endometritis, and iodine-based disinfectants reduced the risk of postoperative fever (risk ratio, 0.58 [0.44-0.77]) and wound infection (risk ratio, 0.75 [0.60-0.94]). With regard to disinfectant concentration, 1% povidone-iodine was most likely to simultaneously reduce the risks of endometritis, postoperative fever, and wound infection. CONCLUSION: Preoperative vaginal preparation can significantly reduce the risk of postcesarean infectious diseases (endometritis, postoperative fever, and wound infection); 1% povidone-iodine has particularly outstanding effects.

Black phosphorus stabilized by titanium disulfide and graphite via chemical bonds for high-performance lithium storage.

Black phosphorus (BP) anode has received extensive attentions for lithium-ion batteries (LIBs) due to its ultrahigh theoretical specific capacity (2596 mAh g-1) and superior electronic conductivity (≈102 S m-1). However, the enormous volume variations during lithiation/delitiation processes greatly limit its applications. Herein, a new BP-titanium disulfide-graphite (BP-TiS2-G) nanocomposite composed of BP, titanium disulfide and graphite has been prepared by a facile and scalable high-energy ball milling method. The experimental data proves that PC and PS bonds have been successfully introduced at the interface, which can effectively maintain the structural integrity of the BP-TiS2-G electrode when evaluated as an anode material for LIBs. In addition, lithium-ion diffusion kinetics have been demonstrated to be enhanced from the synergistic effect of PC and PS bonds. As a result, the BP-TiS2-G anode shows outstanding cycling stability (906.2 mAh g-1 after 1300 cycles at 1.0 A g-1) and superior rate performance (313.8 mAh g-1 at 10.0 A g-1). Our work shows the synergistic effects of different chemical bonds to stabilize BP can be a potential strategy for the development of high-performance alloy-type anodes for rechargeable batteries.

Trumpet-Like ZnS@C Composite for High-Performance Potassium Ion Battery Anode.

ZnS has acquired increasing attention for high-performance PIBs anode because of its remarkable theoretical capacity, and redox reversibility for conversion reaction. However, the larger volume variation and delayed reaction kinetics for the ZnS in the discharge/charge processes lead to pulverization and severe capacity degradation. Herein, the trumpet-like ZnS@C composite was synthesized by template method by using sodium citrate as carbon source followed by vulcanization process. As potassium ion batteries (PIB) anode, ZnS@C composite exhibits good rate performance and long life (stable reversible capacity of 107.8 mAh/g over 2000 charge-discharge cycles at 5 A/g and high reversible capacity of 310 mAh/g at 0.1 A/g). The outstanding electrochemical performance of the ZnS@C composite is ascribed to its unique structure, which can mitigate the volume expansion of ZnS in the charge discharge process, expand the contact area between the electrode and electrolyte, and improve the conductivity of electrode materials by the introduction of carbon layer. This method of synthesizing trumpet-like ZnS@C composite provides an important strategy for obtaining potassium ion batteries anode with long cycle.

Compensation of scale factor nonlinear error introduced by harmonic distortion for open-loop fiber optic gyroscopes.

The scale factor (SF) of a gyroscope is the ratio of the detection output rotational rate and the input, and is expected to be a constant. However, for open-loop interferometric fiber optic gyroscopes (IFOGs) with sinusoidal modulation, harmonic amplitudes are inevitably affected by detection defects, such as nonuniform frequency response of the photodetector or unequal gain of amplification circuits. As a result, harmonic distortion leads to SF nonlinearity, which seriously hinders the accuracy of high-precision gyroscopes. In this Letter, the theoretical form of the SF error introduced by harmonic distortion of open-loop gyroscopes is analyzed, and an effective and simple compensation method is proposed. Instead of traversing the whole dynamic range, the proposed method simplifies the calibration pretest, where only a section of the dynamic range needs to be tested. Experimental results on an open-loop IFOG prototype show that, with our proposed method, the SF nonlinear error is suppressed to 2.5 ppm within the range -300 to +300∘/s, which is 33 times less than that before compensation.

Angular accelerometer based on a dual-polarization fiber-optic Sagnac interferometer.

High-performance angular accelerometers are essential for precise dynamics control of aircraft, satellites, etc. Here, we propose, for the first time to the best of our knowledge, an angular accelerometer based on a dual-polarization fiber-optic Sagnac interferometer, which exhibits relatively high sensitivity and a broad bandwidth. The experimental results show that the angular accelerometer achieves a flat frequency response in the bandwidth range of 0.01-100 Hz. The sensitivity reaches 6.6 × 10-8 rad/s2/Hz. In addition, the proposed fiber-optic angular accelerometer does not rely on any mechanical structure and has strong environmental adaptability. This research provides a feasible solution for the design and implementation of new high-performance angular accelerometers, which contributes to their development in the fields of inertial navigation and rotational seismology.

A Covalent Heterostructure of Metal Phosphide Quantum Dots Anchored in N, P Co-doped Carbon Nanocapsules for Fast and Durable Lithium Storage.

Transition-metal phosphides (TMPs) anodes for lithium ion batteries (LIBs) usually show poor rate capability and rapid capacity degradation owing to their low electronic conductivities, huge volumetric changes, as well as inferior reversibility of the discharge product Li3P. Herein, a covalent heterostructure with TMPs quantum dots anchored in N, P co-doped carbon nanocapsules (NPC) has been prepared in which the P element in TMPs is simultaneously doped into the carbon matrix. As a proof of concept, Co2P quantum dots covalently anchored in NPC (Co2P QDs/NPC) is prepared and evaluated as an anode for LIBs. The Co2P QDs/NPC electrode not only demonstrates a high capacity and an extraordinary rate performance but also delivers an impressive cyclability with a high capacity retention of 102.5% after 1600 cycles, one of the best reported values for TMPs-based electrode materials for LIBs. The covalent heterostructure can facilitate the electron/ion transfer and maintain the structural stability during the intensive cycles. Moreover, density functional theory calculations demonstrate that the interfacial covalent coupling can enhance the electrochemical reversibility of the discharge product Li3P in the charge processes via lowering the conversion reaction energies. This work presents an effective interfacial engineering strategy for developing high-performance TMPs anodes for advanced LIBs.

MiR-509-3p Induces Apoptosis and Affects the Chemosensitivity of Cervical Cancer Cells by Targeting the RAC1/PAK1/LIMK1/Cofilin Pathway.

Chemoresistance is one of the main factors of treatment failure of cervical cancer (CC). Here, we intended to discover the role and mechanism of miR-509-5p in the paclitaxel chemoresistance of CC cells. RT-PCR was conducted to verify miR-509-3p expression. HCC94 and C-33A paclitaxel-resistant CC cell models were constructed. Additionally, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry were performed to verify the viability and apoptosis of HCC94 and C-33A cells after upregulating miR-509-3p. Besides, the downstream target of miR-509-3p was analyzed by bioinformatics, and the targeted relationship between miR-509-3p and RAC1 was identified by the dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Further, the expression of apoptotic proteins (Bcl2, Bax, and Caspase3) and the RAC1/PAK1/LIMK1/Cofilin pathway was monitored by Western blot. The result showed that upregulating miR-509-3p markedly inhibited the viability and promoted the apoptosis of CC cells. On the other hand, miR-509-3p was distinctly downregulated in paclitaxel-resistant HCC94 and C-33A cells (vs. normal cells). The transfection of miR-509-3p mimics notably increased their sensitivity to paclitaxel. Meanwhile, RAC1 was found as the potential target of miR-509-3p in bioinformatics analysis. Moreover, the RAC1/p21 (RAC1) activated kinase 1 (PAK1)/LIM kinase 1 (LIMK1)/Cofilin pathway was significantly activated in paclitaxel-resistant HCC94 and C-33A cells, while miR-509-3p overexpression significantly inactivated this pathway. Additionally, downregulation of RAC1 also partly reversed the paclitaxel-resistance of CC cells and inhibited PAK1/LIMK1/Cofilin. All in all, miR-509-3p enhances the apoptosis and chemosensitivity of CC cells by regulating the RAC1/PAK1/LIMK1/Cofilin pathway.

Suppression of reverberations at fiber tips for optical ultrasound sensing.

Fabry-Perot-based ultrasound sensors at fiber tips have performed high sensitivity and immunity of electromagnetic interference with a relatively compact size. Nevertheless, the reverberation at fiber tips causes a strong noise that degrades the sensing capability. Here we propose a fiber optical-based ultrasound sensor with three design approaches to reduce the reverberation, including designs with an eccentric core, absorptive shield, and arc edge. The effect was experimentally validated with a photoacoustic signal excitation. Compared with bare single-mode fibers in simulation, the low-reverberation design increased the signal-to-noise ratio by 32.1 dB with identical excitation. The experimental results demonstrated the "clean" response with almost invisible reverberations, which was validated by a commercial hydrophone. This research solved the reverberation problems and provided a low-noise design for fiber optic ultrasound sensing.

Endogenous Type I CRISPR-Cas: From Foreign DNA Defense to Prokaryotic Engineering.

Establishment of production platforms through prokaryotic engineering in microbial organisms would be one of the most efficient means for chemicals, protein, and biofuels production. Despite the fact that CRISPR (clustered regularly interspaced short palindromic repeats)-based technologies have readily emerged as powerful and versatile tools for genetic manipulations, their applications are generally limited in prokaryotes, possibly owing to the large size and severe cytotoxicity of the heterogeneous Cas (CRISPR-associated) effector. Nevertheless, the rich natural occurrence of CRISPR-Cas systems in many bacteria and most archaea holds great potential for endogenous CRISPR-based prokaryotic engineering. The endogenous CRISPR-Cas systems, with type I systems that constitute the most abundant and diverse group, would be repurposed as genetic manipulation tools once they are identified and characterized as functional in their native hosts. This article reviews the major progress made in understanding the mechanisms of invading DNA immunity by type I CRISPR-Cas and summarizes the practical applications of endogenous type I CRISPR-based toolkits for prokaryotic engineering.

CXCL5 contributes to the tumorigenicity of cervical cancer and is post-transcriptionally regulated by miR-577.

BACKGROUND: C-X-C motif chemokine ligand 5 (CXCL5), an important chemokine, has been validated to promote human tumorigenesis. However, the clinical significance and the underlying molecular mechanisms of CXCL5 have not been completely explored in cervical cancer. Herein, the aim was to investigate miR-577-mediated CXCL5 signaling in cervical tumorigenicity. MATERIAL AND METHODS: Sixty-one pairs of cervical cancer specimens and para-carcinoma tissues were collected to measure miR-577 and CXCL5 expression levels. miR-577 mimics and/or si-CXCL5 were transfected into cervical cancer cell lines, Hela, and SiHa cells, to determine their effect on cell proliferation, migration and apoptosis. RESULTS: Our results demonstrated that CXCL5 is overexpressed in cervical cancer tissues and cell lines. Knockdown of CXCL5 with specific siRNA transfection in Hela and SiHa cells significantly inhibited cell proliferation and migration and induced apoptosis in vitro. We also report that CXCL5 is a direct target of miR-577. Additionally, transfection of miR-577 mimics can inhibit CXCL5 protein expression, but not mRNA in Hela cells. miR-577 mimic transfection significantly inhibits migration and induces apoptosis in Hela and SiHa cells. However, the antineoplastic activities of miR-577 are reversed by overexpression of CXCL5 in vitro. CONCLUSIONS: Overexpression of CXCL5 is involved in tumor development of cervical cancer. Inhibition of CXCL5 by its post-transcriptional regulator, miR-577, may provide a promising therapeutic strategy for patients with cervical cancer.

Fiber optic-based laser interferometry array for three-dimensional ultrasound sensing.

Ultrasound imaging has been widely used in medical diagnosis due to its noninvasive, radiation-free, and real-time features. Optical resonance-based ultrasound sensors possess high sensitivity and broad bandwidth, but they need to operate in specific laser wavelengths or angles, which restricts their application in array sensing. Non-resonance-based optical sensing arrays did not perform with sufficient bandwidths or frame rates. Here we propose a fiber optic-based ultrasound sensing array with relatively high sensitivity, wide bandwidth, and three-dimensional (3D) sensing capabilities, which is potentially useful in medical imaging. Specifically, we experimentally demonstrated that the optical ultrasound sensor exhibited a noise equivalent pressure of 165 Pa, pressure nonlinearity of ${\lt 5}\% $<5%, $ - {3}\,\,{\rm dB}$-3dB angular uniformity of $ \pm {71}^\circ ,$±71∘, and $ - {6}\,\,{\rm dB}$-6dB bandwidth from $\sim{0}$∼0 to 27.2 MHz. For 3D sensing capabilities in spherical coordinates, the errors of the radial distance were within 5%, and the errors for the polar and azimuthal angles were within 4° and 2°, respectively. This demonstrated the viability and high performance of the array for 3D ultrasound sensing.

Characterization and repurposing of the endogenous Type I-F CRISPR-Cas system of Zymomonas mobilis for genome engineering.

Application of CRISPR-based technologies in non-model microorganisms is currently very limited. Here, we reported efficient genome engineering of an important industrial microorganism, Zymomonas mobilis, by repurposing the endogenous Type I-F CRISPR-Cas system upon its functional characterization. This toolkit included a series of genome engineering plasmids, each carrying an artificial self-targeting CRISPR and a donor DNA for the recovery of recombinants. Through this toolkit, various genome engineering purposes were efficiently achieved, including knockout of ZMO0038 (100% efficiency), cas2/3 (100%), and a genomic fragment of >10 kb (50%), replacement of cas2/3 with mCherry gene (100%), in situ nucleotide substitution (100%) and His-tagging of ZMO0038 (100%), and multiplex gene deletion (18.75%) upon optimal donor size determination. Additionally, the Type I-F system was further applied for CRISPRi upon Cas2/3 depletion, which has been demonstrated to successfully silence the chromosomally integrated mCherry gene with its fluorescence intensity reduced by up to 88%. Moreover, we demonstrated that genome engineering efficiency could be improved under a restriction-modification (R-M) deficient background, suggesting the perturbance of genome editing by other co-existing DNA targeting modules such as the R-M system. This study might shed light on exploiting and improving CRISPR-Cas systems in other microorganisms for genome editing and metabolic engineering practices.

General and Scalable Fabrication of Core-Shell Metal Sulfides@C Anchored on 3D N-Doped Foam toward Flexible Sodium Ion Batteries.

Flexible self-standing transitional metal sulfides (TMSs)/carbon nanoarchitectures have attracted widespread research interests for sodium ion batteries (SIBs), thanks to their enormous capability to address intrinsic issues of TMSs for SIBs applications. However, controllable synthesis of hierarchical hybrid structures is always laborious and involves complicated procedures. Herein, a simple yet general and scalable adsorption-annealing strategy is first devised to finely construct core-shell carbon-coated TMSs (TMSs@C, including Co9 S8 @C, FeS@C, Ni3 S2 @C, MnS@C, and ZnS@C) nanoparticles anchored on 3D N-doped carbon foam (3DNCF) via the coordination and hydrogen-bond adsorption. Benefiting from synergistic contributions from strong chemical affinity between nanodimensional TMSs and 3DNCF, efficient electronic/ionic transport channels, as well as a uniform carbon accommodating layer, the resulted self-standing TMSs@C/3DNCF electrodes exhibit distinguished sodium storage performances, including large reversible capacities, high rate behaviors, and exceptional long-span cycle stability in both half cells and flexible full devices. More significantly, the smart methodology developed holds huge promise for commercialization of binder-free TMSs@C/3DNCF anodes toward advanced flexible SIBs.

Retardation of Trap-Assisted Recombination in Lead Halide Perovskite Solar Cells by a Dimethylbiguanide Anchor Layer.

Reaching the full potential of solar cells based on photo-absorbers of organic-inorganic hybrid perovskites requires highly efficient charge extraction at the interface between perovskite and charge transporting layer. This demand is generally challenged by the presence of under-coordinated metal or halogen ions, causing surface charge trapping and resultant recombination losses. These problems can be tackled by introducing a small molecule interfacial anchor layer based on dimethylbiguanide (DMBG). Benefitting from interactions between the nitrogen-containing functional groups in DMBG and unsaturated ions in CH3 NH3 PbI3 perovskites, the electron extraction of TiO2 is dramatically improved in association with reduced Schottky-Read-Hall recombination, as revealed by photoluminescence spectroscopy. As a consequence, the power conversion efficiency of CH3 NH3 PbI3 solar cells is boosted from 17.14 to 19.1 %, showing appreciably reduced hysteresis. The demonstrated molecular strategy based on DMBG enables one to achieve meliorations on key figures of merit in halide perovskite solar cells with improved stability.