MICROCHIMICA ACTA
·
2024
·Vol. 191
·期 7
·1-11
·
IF 5.3
Liang Pengda,Lv Bei,Chen Ke,Li Dawei
The combination of CRISPR/Cas12a and functional DNA provides the possibility of constructing biosensors for detecting non-nucleic-acid targets. In the current study, the duplex protospacer adjacent motif (PAM) in the activator of CRISPR/Cas12a was used as a molecular switch, and a sensitive adenosine triphosphate (ATP) detection biosensor was constructed using an allosteric probe-conjugated PAM site formation in hybridization chain reaction (HCR) integrated with the CRISPR/Cas12a system (APF-CRISPR). In the absence of ATP, an aptamer-containing probe (AP) is in a stem-loop structure, which blocks the initiation of HCR. In the presence of ATP, the structure of AP is changed upon ATP binding, resulting in the release of the HCR trigger strand and the production of long duplex DNA with many PAM sites. Since the presence of a duplex PAM site is crucial for triggering the cleavage activity of CRISPR/Cas12a, the ATP-dependent formation of the PAM site in HCR products can initiate the FQ-reporter cleavage, allowing ATP quantification by measuring the fluorescent signals. By optimizing the sequence elements and detection conditions, the aptasensor demonstrated superior detection performance. The limit of detection (LOD) of the assay was estimated to be 1.16 nM, where the standard deviation of the blank was calculated based on six repeated measurements. The dynamic range of the detection was 25–750 nM, and the whole workflow of the assay was approximately 60 min. In addition, the reliability and practicability of the aptasensor were validated by comparing it with a commercially available chemiluminescence kit for ATP detection in serum. Due to its high sensitivity, specificity, and reliable performance, the APF-CRISPR holds great potential in bioanalytical studies for ATP detection. In addition, we have provided a proof-of-principle for constructing a CRISPR/Cas12a-based aptasensor, in which the PAM is utilized to regulate Cas12a cleavage activity. Graphical Abstract
研究领域:
生物化学
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分子生物学
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分析化学
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产品关联
DOI
PubMed
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2024
·
IF 6.5
Teng Zhou,Xiao Zhan,Kunlan Diao,Jiajia Du,Yuhuan Xu,Jingyu Du,Renyuan Yang,Shuhao Qin,Daohai Zhang
With the continuous development of electronic products, polymers with EM shielding have received widespread attention. In this study, Fe 3 O 4 @RGO was prepared by the hydrothermal synthesis method, which solved the problems of Fe 3 O 4 precipitation and RGO stacking. Using it as a precursor, Fe 3 O 4 @RGO/PAM conductive hydrogel was prepared. The research shows that the conductivity of this hydrogel reaches 16.2 S/m at a thickness of 0.3 cm, and the maximum EMI SE is 27.1 dB. Among them, RGO can form a conductive framework, and Fe 3 O 4 can optimize the impedance matching and provide additional magnetic loss. The combined effect of the two makes the hydrogel have excellent EMI SE. In addition, PAM-based hydrogels have good thermal stability, crystallinity, water content, and mechanical properties.
研究领域:
材料科学
·
电磁学
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 140
·期 36
·e54322
·
IF 3
Cunyue Wei,Kun Li,Feng Lin,Shengli Mi,Lina Dong,Yu Song,Ting Zhang
Hydrogels are characterized by high water content and are typically used in water environments. However, when used in air environments, hydrogels face limitations due to instability caused by water loss. This study reports the development of PAM/glycerol hydrogels with improved stability. By using water–glycerol bi-solvents to lock in water internally, a closed environment was established to reduce water exchange with the outside world. The hydrogel was made by forming a single PAM crosslinking network using UV crosslinked acrylamide (AM) monomer. The weight of the hydrogel varied by no more than 2% within 6 days, and the visible light transmittance was higher than 90%. In addition, the hydrogel had adjustable refractive index and mechanical properties. The hydrogels with stable performance could be used to fabricate optical lens with practical function in air environment. Meanwhile, the gels also have certain advantages in making a fluid-driven hydrogel actuator with stable performance.
研究领域:
材料科学
·
生物医学工程
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Lisha Pu,Zhiang Yuan,Yuting Cai,Xusheng Li,Zhongxin Xue,Yuzhong Niu,Yan Li,Songmei Ma,Wenlong Xu
Currently, the development of hydrogels with excellent mechanical properties (elasticity, fatigue resistance, etc.) and conductive properties can better meet their needs in the field of flexible sensor device applications. Generally, hydrogels with a denser cross-linking density tend to have better mechanical properties, but the improvement in mechanical properties comes at the expense of reduced electrical conductivity. Directly generating CaCO3 in the hydrogel prepolymer can not only increase the cross-linking density of its network but also introduce additional ions to enhance its internal ionic strength, which is beneficial to improving the conductivity of the hydrogel. It is still a big challenge to directly generate CaCO3 in the static prepolymer solution and ensure its uniform dispersion in the hydrogel. Herein, we adopted an improved preparation method to ensure that the directly generated CaCO3 particles can be evenly dispersed in the static prepolymer solution until the polymerization is completed. Finally, a PAM/PVA/CaCO3 hydrogel with supertensile, compressive, toughness, and fatigue resistance properties was prepared. In addition, the presence of free Na+ and Cl– gives the hydrogel excellent conductivity and sensing performance to monitor daily human activities. On the basis of the application of hydrogels in information communication, we have further deepened this application by combining the characteristics of hydrogels themselves. Combined with ASCII code, the hydrogel can also be applied in information exchange and information encryption and decryption, achieving the antitheft function in smart locks. A variety of excellent performance integrated PAM/PVA/CaCO3 hydrogels have broad application prospects for flexible sensors, highlighting great potential in human–computer interaction and intelligent information protection.
研究领域:
材料科学
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生物医学工程
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智能材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Genes
·
2025
·Vol. 16
·期 2
·217
·
IF 2.8
Haiyan Shu,Aiping Luan,Hidayat Ullah,Junhu He,You Wang,Chengjie Chen,Qing Wei,Rulin Zhan,Shenghe Chang
Background/Objectives: CRISPR-Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats)-associated protein 9 is now widely used in agriculture and medicine. Off-target effects can lead to unexpected results that may be harmful, and these effects are a common concern in both research and therapeutic applications. Methods: In this study, using pineapple as the gene-editing material, eighteen target sequences with varying numbers of PAM (Protospacer-Adjacent Motif) sites were used to construct gRNA vectors. Fifty mutant lines were generated for each target sequence, and the off-target rates were counted. Results: Selecting sequences with multiple flanking PAM sites as editing targets resulted in a lower off-target rate compared to those with a single PAM site. Target sequences with two 5′-NGG (“N” represents any nucleobase, followed by two guanine “G”) PAM sites at the 3′ end exhibited greater specificity and a higher probability of binding with the Cas9 protein than those only with one 5′-NGG PAM site at the 3′ end. Conversely, although the target sequence with a 5′-NAG PAM site (where “N” is any nucleobase, followed by adenine “A” and guanine “G”) adjacent and upstream of an NGG PAM site had a lower off-target rate compared to sequences with only an NGG PAM site, their off-target rates were still higher than those of sequences with two adjacent 5′-NAG PAM sites. Among the target sequences of pineapple mutant lines (AcACS1,AcOT5,AcCSPE6,AcPKG11A), more deletions than insertions were found. Conclusions: We found that target sequences with multiple flanking PAM sites are more likely to bind with the Cas9 protein and induce mutations. Selecting sequences with multiple flanking PAM sites as editing targets can reduce the off-target effects of the Cas9 enzyme in pineapple. These findings provide a foundation for improving off-target prediction and engineering CRISPR-Cas9 complexes for gene editing.
CAS / MDL:
研究领域:
植物学
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遗传学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
ChemistrySelect
·
2022
·Vol. 7
·期 47
·e202200923
·
IF 2.307
Qi Peiyao,Wang Shuo,Ju Ye,Tang Zhongli,Qu Jin,Zheng Junping,Liu Xiaofei
Graphical SiO 2 /PAM composite nanospheres were synthesized by the inverse microemulsion method to meet the needs of profile control and water shutoff in oilfields. The structure, oil displacement effect and rheological properties of polyacrylamide nanospheres and SiO 2 /PAM composite nanospheres were comparatively studied. This work provides a basis for the practical application of SiO 2 /PAM composite nanospheres in oilfields. Polyacrylamide nanospheres are a kind of polymer material that can improve the development effect of oilfield water flooding and realize reservoir stimulation. However, due to its good water absorption, the strength cannot well meet the needs of practical production, and is forced to be limited to application on oil displacement. Therefore, in this paper, SiO 2 /PAM composite nanospheres were synthesized by the inverse microemulsion method to meet the needs of profile control and water shutoff in oilfields. The structure, oil displacement effect and rheological properties of polyacrylamide nanospheres and SiO 2 /PAM composite nanospheres were comparatively studied. The results show that both nanospheres are viscoelastic nanospheres. Since the elastic response is greater than the viscous response in SiO 2 /PAM composite nanospheres, and the polymer nanospheres do the opposite, there are significant differences in various rheological properties, such as variation of apparent viscosity with shear rate, creep recovery characteristics, viscoelasticity etc. This work provides a basis for the practical application of SiO 2 /PAM composite nanospheres in oilfields.
研究领域:
石油工程
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材料科学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Kailu Wang,Shangwei Wang,Xiaoyu Wang,Xiaoqing Wang,Lijun Zheng,Jie Wen,Huan Yang,Hui Zhang
To address the issue of traditional gels being prone to dewatering and failure under reservoir conditions, this study prepared a new type of magnetic smart gel by 'chelating' PEI@Fe 3 O 4 @PEI nanosheets within the PAM-PEI gel network. The nanosheets possess a 'sandwich' structure formed through self-assembly driven by electrostatic forces, with a density of 2.719 g/cm 3 . Under 90 °C and with a NaCl concentration of 25 g/L, the control PAM-PEI gel had a syneresis rate of 5.96 % and a gel strength of 17.13 Pa·s. In comparison, the magnetic smart gel had a syneresis rate of 0 % and a gel strength of 27.38 Pa·s, indicating that the magnetic smart gel outperformed the control significantly. Possible mechanisms by which nanosheets enhance the performance of magnetic smart gels include: enhancing the hydrophilicity of the molecular chains, inhibiting the breakage of C-N bonds in the polymer chains, increasing the gel's resistance to water loss at high temperatures, and hindering the pyrolysis of PAM groups. Lastly, the work explores the advantages of magnetic smart gels in effective plugging, rapid unplugging post-lifespan, and simplified produced water treatment through its controlled operational capabilities. To implement these applications effectively, field devices need to be equipped with innovative designs.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Liangmiao Zhang,Changzheng Pan,Jian Wu,Yi Du,Fang Xia,Yanfeng Gao
Hydrogels demonstrate significant potential as materials for fabricating energy-saving smart windows. Nevertheless, their liquid nature poses challenges and renders them susceptible to leakage during operation. In this study, we developed an HPC-PAA-PAM semi-solid hydrogel through a two-step polymerization process at 80 °C, with acrylamide serving as the curing agent. The resulting hydrogel exhibited a precisely tunable lower critical solution temperature (LCST) spanning from 31.5 °C to 36.2 °C. Additionally, we constructed double-layered glass-encapsulated HPC-PAA-PAM semi-solid hydrogel smart windows, which demonstrated remarkable optical transmittance (T lum = 88.3 %), excellent solar energy modulation (ΔT sol = 47.9 %), and remained stability through 100 heating and cooling cycles. Thermal regulation tests conducted in model houses revealed outstanding heat-shielding performance of these hydrogel smart windows, surpassing conventional double-glazed windows and double-glass encapsulated water windows. Notably, after 90 days of outdoor exposure, the HPC-PAA-PAM semi-solid hydrogel smart window experienced only a minimal reduction in solar modulation, underlining its exceptional weather durability in practical applications. Consequently, the HPC-PAA-PAM semi-solid hydrogel presents substantial promise for the production of smart windows, particularly suited for energy-efficient buildings in tropical and subtropical regions, where it can effectively prevent the intense summer sun's heat from penetrating indoors, fostering a more pleasant indoor temperature.
研究领域:
材料科学
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能源工程
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产品关联
DOI
高影响因子
CORROSION SCIENCE
·
2025
·
IF 8.5
Ru Yan,Xiao Zhang,Xiang Gao,Wei He,Houyi Ma
PAM formed by self-organization can be considered as nanocontainers of phytic acid (PA) molecules and used for the corrosion protection of metal materials. Herein, self-strengthening PAM-Zn conversion films were successfully constructed on CRS substrate by a simple dipping method. The highest protection efficiency of PAM-Zn films was 81.0 % and was further increased beyond 90 % after immersion in NaCl solution. The immersion treatment in NaCl solution not only promoted the formation of more P O 4 3 − and PAM-Zn complex, but also changed the surface microstructure and increased the film thickness and compactness, thereby leading to the great enhancement of anti-corrosion performance.
研究领域:
材料科学
·
腐蚀与防护
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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2024
·
IF 8
Kai Zhang,Yuwen Bao,Changjin Ou,Guoyin Zhu,Yizhou Zhang
This study presents a novel biosensor that integrates CRISPR-Cas12a technology with DNA tile-based architectures to enhance thrombin detection. Utilizing PAM-engineered toehold switches, the biosensor dynamically activates the CRISPR-Cas12a system upon thrombin recognition, significantly improving both sensitivity and specificity. The label-free electrochemical detection method offers rapid, cost-effective analysis, making it ideal for real-time clinical applications. The biosensor achieved an impressive detection limit of 103 aM, surpassing traditional methods and setting a new standard for thrombin assays. The biosensor's robust performance in complex biological samples, such as diluted human serum, demonstrates its reliability for clinical diagnostics. This is particularly important for the early diagnosis and management of thrombotic and coagulation-related disorders. By combining advanced genetic engineering with traditional electrochemical techniques, the biosensor not only optimizes detection but also expands its potential applications across various biomedical fields. Overall, this biosensor provides a powerful and innovative tool for thrombin detection, offering enhanced diagnostic accuracy, faster patient management, and potential cost savings in healthcare. Its superior performance and adaptability highlight its promise for broader adoption in clinical diagnostics and other biosensing applications.
研究领域:
分子生物学
·
医学诊断
·
生物传感技术
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY
·
2024
·
IF 6
Xiangfei Kong,Yue Han,Jianjuan Yuan,Xuemei Zhang
As a bridge connecting indoor and outdoor environment, windows cause extremely high energy consumption, and near infrared light entering rooms is the primary reason for the increase of cooling load in summer. Thermochromic smart windows, which dynamically regulate light transmittance through stimulus–response mechanism, aroused enormous interest in building energy-saving. However, the development of traditional thermochromic smart windows is often limited by single function and inappropriate response temperature. Herein, a novel fully autonomous multi-stage thermal-response@storage (MTRS) smart window that responds to the ambient temperature was designed by using the thermoresponsive SPCM@PNIPAm-PAM hydrogel for energy-saving and privacy protection. The SPCM@PNIPAm-PAM hydrogel exhibited satisfactory luminous transmittance of 62.70 % and solar modulation ability ( Δ T s o l , 25 - 40 ° C =27.39 %, Δ T s o l , 40 - 55 ° C = 19.28 %). With the temperature changing from low (<28 °C) to medium (28–45 °C) to high (>45 °C), the MTRS smart window realized the multi-stage reversible transition from opaque to transparent to opaque, which achieved privacy protection at night and thermal insulation during the day. The obtained MTRS smart window achieved a peak temperature drop of 12.14 °C compared with the regular window on a certain day in the midsummer in Tianjin region. Based on this day’s temperature data, the cooling load of was calculated, and the energy saving was further calculated, which was as high as 21.37 %. The proposed work has a great significance for further development of effective smart windows and deserves attention for the future design of windows for energy saving.
研究领域:
材料科学
·
能源工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Yijie Duan,Yifu Gao,Zetao Ren,Yehui Li,Zhichun Si,Hongda Du,Yanbing He,Dong Zhou,Wei Lv,Feiyu Kang
Water scarcity has become a global problem and caused a lot of conflicts. Atmospheric water harvesting (AWH) is a promising way to address water shortage issue. However, traditional adsorbent materials such as silica gels and zeolites suffer from low water productivity and high regeneration temperature. Hygroscopic salts like LiCl are regarded as a perspective substitution. Salt-modified metal organic frameworks (MOFs) and hydrogels are employed to alleviate the salt aggregation but they are limited to expensive fabrication or sluggish adsorption kinetics. Herein, we demonstrate an asymmetric double-layer design of LiCl@CC (carbon cloth)/PAM with separated function of water adsorption/desorption and water storage in different layer. This double-layer design not only enhances the mechanical properties but also shows an improved water adsorption kinetics compared to common salt-composite hydrogels. In experimental test, the LiCl@CC/PAM exhibits excellent water uptake of 1.5 g g −1 under 60 % RH in 4 h and fast water desorption under sunlight in 1.5 h. In outdoor test, LiCl@CC/PAM based device presents a daily water uptake of 5.12 g g −1 day −1 . Meanwhile, all the materials used and fabrication process are feasible to scale up, which provides a possible solution to the global crisis of water scarcity.
研究领域:
材料科学
·
环境科学
·
水资源工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）