Analytical Methods
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2020
·Vol. 12
·期 31
·3933-3943
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IF 2.596
Qiuyue Yin,Maiqian Nie,Zhenjun Diwu,Yuting Zhang,Lei Wang,Dandan Yin,Liancheng Li
A rapid method for readily detecting the total numbers of viable bacterial cells in numerous samples (including surface water, solid inoculants, and soil samples) is reported using a newly developed hand-held fluorometer and a fluorescent dye Calcein UltraGreen™ AM. Compared to the traditional plate counting method that requires 48 hours of cultivation, the newly established method does not require any incubation time, making the detection method faster and more convenient. The portable rapid detection fluorometer has a wide dynamic range of relative fluorescence intensity from 45 to 30 133. It can detect bacterial concentration ranging from 105 to 1010 cells per mL. This newly established method has good applicability for accurately and quickly detecting the cell number of viable bacteria in various samples. The results of the fluorescence-based method were compared with those of the traditional plate counting method, and it was found that the relative standard deviation was less than 6%. This new rapid measurement system provides a robust method for the rapid on-site detection of viable bacteria.
研究领域:
微生物学
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环境科学
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分析化学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Jianxu Bao,Shifan Chen,Xianda Liu,Ziyue Ling,Chunji Jiang,Zhaoxi Han,Wenjie Wang,Ran Wei,Changsheng Zhao,Weifeng Zhao
Sepsis is a life-threatening systemic inflammatory response syndrome mainly caused by bacterial infection. Directly capturing live bacteria from blood could effectively avoid the activation of pathogen-associated molecular patterns. Despite the availability of numerous materials capable of capturing bacteria, most of these materials will negatively affect blood cells and thus exhibit poor blood compatibility. Given that bacteria are generally smaller than blood cells, we designed a fiber with a groove, where the groove width is larger than bacteria but smaller than blood cells, and trace amounts of positively charged copolymers are loaded into the grooves. This sophisticated design allows the grooved fibers to capture bacteria efficiently as well as maintain good blood compatibility. In vitro experiments show that bacteria could be trapped inside the groove and the fibers can remove over 98% of bacteria. In rabbits’ bacteremia model, these fibers significantly reduce bacterial concentration and endotoxin level, offering a promising therapeutic approach for the treatment of bacteremia. Groove shaped fiber exhibits excellent blood compatibility in both in vitro and in vivo environments. The developed groove shaped fiber opens a new pathway to design functional materials for extracorporeal blood purification.
研究领域:
生物医学工程
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材料科学
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感染性疾病研究
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产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 187
·期 1
·1-10
·
IF 5.479
Zhang Xuzhi,Wang Xiaochun,Yang Qianqian,Jiang Xiaoyu,Li Yang,Zhao Jun,Qu Keming
A method is described to determine viable populations of Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ). The method employs aptamer-magnetic separation combined with resistivity based detection. The bacteria were separated by means of aptamer-functionalized magnetic beads. They were then quantified by measuring their growth kinetics through time-dependent conductivity changes of culture media. The time-course of growth was logged by real-time and contactless measurements that yielded starting concentrations from the duration of lag intervals prior to the log phase of growth. In pure water samples, the linear ranges for measuring E. coli and S. aureus cells are 2.5 × 10 3 –2.5 × 10 8 CFU·mL −1 and 4.1 × 10 3 –4.1 × 10 8 CFU·mL −1 , respectively. In spiked tap water samples, the lower limits of detection are 2.3 × 10 4 CFU·mL −1 and 4.0 × 10 3 CFU·mL −1 for E. coli and S. aureus , with recoveries of 87.0–108.7% and 92.5–105.0%, respectively. The relative standard deviation of these measurements (10.0%) is below that of plate counting method (13.9%). The presence of micro/nanoparticles such as magnetic beads or selenium nanoparticles in the culture media does not interfere, unlike in case of automatted optical density monitoring. The E. coli and S. aureus cells captured on the aptamer-functionalized magnetic beads can be directly tested for their susceptibility to antibiotics. The process of magnetic separation and determination of load burden requires neither bulky, sophisticated equipment nor expensive reagents.
Aptamer-functionalized magnetic beads are used to selectively capture and separate E. coli and S. aureus cells in aqueous samples. They are directly transferred to a multichannel conductometric sensor for the quantification of viable bacteria via automated monitoring of their growth kinetics.
研究领域:
微生物学
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分析化学
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生物技术
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产品关联
DOI
PubMed
高影响因子
Bioactive Materials
·
2022
·
IF 16.874
Xinhua Liu,Youteng Qin,Liyun Dong,Ziyi Han,Tianning Liu,Ying Tang,Yun Yu,Jingjie Ye,Juan Tao,Xuan Zeng,Jun Feng,Xian-Zheng Zhang
Many skin diseases, such as atopic dermatitis (AD), are featured with the dysbiosis of skin microbiota. The clinically recommended options for AD treatments suffer from poor outcomes and high side-effects, leading to severe quality-of-life impairment. To deal with this long-term challenge, we develop a living bacterial formulation ( [email protected] ) that integrates skin symbiotic bacteria of Roseomonas mucosa with poly(vinyl pyrrolidone), poly(vinyl alcohol) and sodium alginate into a skin dressing by virtue of the Ca 2+ -mediated cross-linking and the freezing-thawing (F-T) cycle method. [email protected] dressing creates a favorable condition to not only serve as extrinsic culture harbors but also as nutrient suppliers to support R . mucosa survival in the harsh microenvironment of AD sites to defeat S. aureus, which predominantly colonizes AD skins as an indigenous pathogen, mainly through the secretion of sphingolipids metabolites by R . mucosa like a therapeutics bio-factory. Meanwhile, this elaborately designed skin dressing could accelerate wound healing, normalize aberrant skin characters, recover skin barrier functions, alleviate AD-associated immune/inflammation responses, functioning like a combinational therapy. This study offers a promising means for the topical bacteria transplant to realize effective microbe biotherapy toward the skin diseases feature with microbe milieu disorders, including but not limited to AD disease.
研究领域:
皮肤病学
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微生物学
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生物技术
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免疫学
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产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Jian-Hua Yan,Sheng-Xin Jin,Qi-Wen Chen,Yun Zhang,Qian-Ru Li,Zhu Chen,Yunxia Sun,Zhenlin Zhong,Xian-Zheng Zhang
Despite its significant potential in various disease treatments and diagnostics, microbiotherapy is consistently plagued by multiple limitations ranging from manufacturing challenges to in vivo functionality. Inspired by the strategy involving nonproliferating yet metabolically active microorganisms, we report an intracellular gelation approach that can generate a synthetic polymer network within bacterial cells to solve these challenges. Specifically, poly(ethylene glycol dimethacrylate) (PEGDA, 700 Da) monomers are introduced into the bacterial cytosol through a single cycle of freeze–thawing followed by the initiation of intracellular free radical polymerization by UV light to create a macromolecular PEGDA gel within the bacterial cytosol. The molecular crowding resulting from intracytoplasmic gelation prohibits bacterial division and confers robust resistance to simulated gastrointestinal fluids and bile acids while retaining the ability to secrete functional proteins. Biocompatibility assessments demonstrate that the nondividing gelatinized bacteria are effective in alleviating systemic inflammation triggered by intravenous Escherichia coli injection. Furthermore, the therapeutic efficacy of gelatinized Lactobacillus rhamnosus in colitis mice provides additional support for this approach. Collectively, intracellular gelation indicates a universal strategy to manufacture next-generation live biotherapeutics for advanced microbiotherapy.
研究领域:
生物技术
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药理学
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微生物学
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治疗学
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DOI
高影响因子
Nanoscale
·
2023
·Vol. 15
·期 20
·9148-9161
·
IF 6.7
Zheng Liu,Hong Ding,Miaomiao He,Yulin Jiang,Lin Qi,Meixuan Du,Jing Wang,Yubao Li,Limin Liu,Ganjun Feng,Li Zhang
Desirable antibacterial and osseointegration abilities are essentially important for long-term survival of a Ti-orthopedic implant. Herein, a near-infrared light (NIR) excited antibacterial platform with excellent osseointegration composed of perovskite calcium titanate/nickel hydroxide on a Ti implant (Ni(OH)2@CaTiO3/Ti) was designed and successfully fabricated. The construction of the heterostructure efficiently separated the photogenerated electron–hole pairs to produce sufficient reactive oxygen species (ROS), which enabled the photoactivated bacterial inactivation (PBI) of Ti implants. The results showed that the surface-modified Ti implant displayed remarkable antibacterial ability with bacterial inhibition rates of 95.5% for E. coli and 93.8% for S. aureus under NIR excitation. Also, the intervention of Ni(OH)2 could create a slightly alkaline surface on the Ti implant, which synchronized with Ca-rich CaTiO3 to regulate the osteogenic microenvironment in favor of the adhesion, proliferation and differentiation of MC3T3-E1 cells as well as the up-regulation of osteogenesis-related gene expressions. The in vivo implantation experiments further confirmed that the heterostructured coating prominently accelerated the formation of new bone and promoted the osseointegration of Ti implants. Our work may provide a novel concept for improving the antibacterial and osseointegration abilities of Ti implants in orthopedic and dental applications.
研究领域:
材料科学
·
生物材料
·
骨科
·
牙科科学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2022
·
IF 18.027
Pei Pei,Yu Zhang,Yunchun Jiang,Wenhao Shen,Hua Chen,Sai Yang,Yanxiang Zhang,Xuan Yi,Kai Yang
Biomaterial-based pleiotropic immune activation may effectively improve the response rate of immunotherapy and enhance the therapeutic effect of the tumor. Bacteria as a natural carrier have demonstrated great advantages in tumor targeted delivery and immune activation of the body. Herein, we construct an inactivated bacteria vector with 125I/131I labeling (125I-VNP/131I-VNP), which could retain radioiodine at the tumor site for a long time and deliver it into tumor cells and a tumor-associated macrophage (TAM), thus achieving efficient internal radioisotope therapy (IRT) of the primary tumor with good biosafety. More importantly, 131I-VNP-mediated local IRT could further stimulate robust systemic antitumor immune responses via activation of the cGAS-STING pathway of innate immunity and promotion of the maturation of DC cells for T-cell-dominated adaptive immunity. After combination with systemic checkpoint blockade therapy (αPD-L1), 131I-VNP, which induces the up-regulation of PD-L1 expression in the distant tumor, could lead to the inhibition of in situ colon cancer and protection against tumor rechallenge. Our strategy pioneers the use of an inactivated bacteria vector as a bridge to cleverly connect radiotherapy and immunotherapy and provide an enlightening idea for radio-immunotherapy mediated by pleiotropic immune activation functions of bacterial vectors.
研究领域:
癌症免疫疗法
·
放射生物学
·
分子生物学
·
免疫学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）