-
Small (Weinheim An Der Bergstrasse,... May 2022Adhesion of single cells is the foundation of manifold cellular behaviors and life processes. However, investigating the function of a specific cell is still challenging...
Adhesion of single cells is the foundation of manifold cellular behaviors and life processes. However, investigating the function of a specific cell is still challenging due to deficiency of adhesion or interference from surrounding cells. Herein, an open microfluidic system is reported for culturing adherent single cells, implemented by a micrometer-scale droplet matrix on an inkjet-printed polylysine template. The target cells are isolated from any cell from other droplets, and their adhesion strength is determined to be comparable to conventional petri dishes via an in-situ investigation with a microfluidic extractor. On this proposed platform, isolated single cells are observed to display an entirely distinct spreading behavior featuring total absence of elongation, indicating drastic cell behavior change from their "singleness." This system has high versatility and compatibility for various assaying methods, assuring a promising potential in detailed single cell behavior and cell heterogeneity studies.
Topics: Cell Culture Techniques; Microfluidic Analytical Techniques; Microfluidics; Polylysine
PubMed: 35362237
DOI: 10.1002/smll.202107992 -
Macromolecular Bioscience Dec 2019The development of tumor targeted probes with strong signal and high contrast is always challenging in cancer imaging. Here, a unique multilayered activatable nanoprobe...
The development of tumor targeted probes with strong signal and high contrast is always challenging in cancer imaging. Here, a unique multilayered activatable nanoprobe (MAN) is prepared to fulfill this long-standing goal. MAN adopts a versatile layer-by-layer fabrication technique that sequentially assembles multifunctional polyelectrolytes onto nanoparticles via charge-charge interaction. Unlike the common one-probe-one-fluorochrome construct, MAN offers a dramatic fluorescence enhancement by transporting a large quantity of quenched fluorochromes for maximal signal and contrast. Excellent signal amplification and retention with negligible cytotoxicity is observed in cell study. Upon systemic injection into mice, MAN quickly accumulates in tumor and its fluorescent signal is turned on by proteases overexpressed in tumors, resulting in >700% tumor-to-normal-tissue contrast. This multilayered fabrication provides a simple and powerful universal platform to design sensitive tumor imaging probes.
Topics: Animals; Breast Neoplasms; Carbocyanines; Cell Line, Tumor; Cell Survival; Female; Heterografts; Humans; Injections, Intravenous; Light; Mice; Mice, Nude; Molecular Imaging; Molecular Probes; Nanoparticles; Neoplasm Proteins; Peptide Hydrolases; Polyelectrolytes; Polylysine; Signal-To-Noise Ratio; Static Electricity
PubMed: 31743618
DOI: 10.1002/mabi.201900260 -
Food Chemistry Oct 2023PVA/CC/CUR/PL composite films containing curcumin (CUR) and ε-polylysine (PL) were prepared by casting and chemical grafting methods to address the threat to food...
PVA/CC/CUR/PL composite films containing curcumin (CUR) and ε-polylysine (PL) were prepared by casting and chemical grafting methods to address the threat to food spoilage. Morphological analysis showed that the grafting of CUR and PL resulted in a rough cross-section of the polymer matrix. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis confirmed the grafting of CUR and PL into the polymer matrix via esterification and amidation reactions, respectively. Thermal weight loss analysis showed that grafting process positively improved the thermal stability. The PVA/CC/CUR/PL films exhibited strong bactericidal activity, reaching 99.0% and 99.8% for Pseudomonas lundensis and Shewanella putrefaciens, respectively. After 8 days of storage, the total number of colonies and the TVB-N content in the PVA/CC/CUR/PL group decreased by 1.51 lg CFU/g and 13.77 mg/100 g, respectively. Therefore, PVA/CC/CUR/PL films are considered as a promising bactericidal material with good mechanical properties, functionality, and other excellent characteristics.
Topics: Animals; Polylysine; Cellulose; Curcumin; Chickens; Hydrogels; Anti-Bacterial Agents
PubMed: 37224635
DOI: 10.1016/j.foodchem.2023.136345 -
Macromolecular Bioscience Aug 20228-Arm star polypep(o)ides comprising cationic polylysine and hydrophilic polysarcosine blocks with a degree of polymerization (DP) of 30 per block are synthesized. Two...
Systematic Study of Enzymatic Degradation and Plasmid DNA Complexation of Mucus Penetrating Star-Shaped Lysine/Sarcosine Polypept(o)ides with Different Block Arrangements.
8-Arm star polypep(o)ides comprising cationic polylysine and hydrophilic polysarcosine blocks with a degree of polymerization (DP) of 30 per block are synthesized. Two different block sequences with polylysine as the inner and polysarcosine as the outer block and vice versa are obtained in addition to a statistical copolymer. Analysis of the enzymatic hydrolysis by the proteolytic enzyme trypsin demonstrates a strong dependence on structural arrangements. While polypept(o)ide disintegration is detectible after 24 h by Size Exclusion Chromatography (SEC), significant hydrolysis of the lysine blocks is only monitored after 48 h by fluorescamine labeling of the produced lysine and clearly accelerated in structures with more accessible polylysine blocks. All structures are capable of complexing plasmid DNA and form gene nanomedicines at sizes around or below 200 nm as determined by Dynamic Light Scattering (DLS), Nanoparticle Tracking Analysis (NTA), and Transition Electron Microscopy (TEM). The polyplex formation is slightly enhanced for both block structures over the random copolypept(o)ide. Moreover, it is demonstrated that the polyplexes can transport through mucus. The results highlight the importance of structural control in compartmentalized polymeric gene vector candidates with hydrophilic domains for potential mucosal delivery.
Topics: DNA; Mucus; Plasmids; Polylysine; Polymers; Sarcosine
PubMed: 35634688
DOI: 10.1002/mabi.202200175 -
Journal of Materials Chemistry. B Jan 2022The temporary silencing of disease-associated genes utilising short interfering RNA (siRNA) is a potent and selective route for addressing a wide range of life limiting...
The temporary silencing of disease-associated genes utilising short interfering RNA (siRNA) is a potent and selective route for addressing a wide range of life limiting disorders. However, the few clinically approved siRNA therapies rely on lipid based formulations, which although potent, provide limited chemical space to tune the stability, efficacy and tissue selectivity. In this study, we investigated the role of molar mass and histidinylation for poly(lysine) based non-viral vectors, synthesised through a fully aqueous thermal condensation polymerisation. Formulation and studies revealed that higher molar mass derivatives yielded smaller polyplexes attributed to a greater affinity for siRNA at lower N/P ratios yielding greater transfection efficiency, albeit with some cytotoxicity. Histidinylation had a negligible effect on formulation size, yet imparted a moderate improvement in biocompatibility, but did not provide any meaningful improvement over silencing efficiency compared to non-histidinylated derivatives. This was attributed to a greater degree of cellular internalisation for non-histidinylated analogues, which was enhanced with the higher molar mass material.
Topics: Cell Line, Tumor; Cell Membrane; Drug Carriers; Gene Knockdown Techniques; Gene Silencing; Histidine; Humans; Molecular Structure; Molecular Weight; Polylysine; RNA, Small Interfering
PubMed: 34852030
DOI: 10.1039/d1tb01793d -
Carbohydrate Polymers Jul 2022Oxidized bacterial nanocellulose (O-BNC) is a favorable material to subdue bacterial infection because of the carboxylate content that not only has a weak antibacterial...
Oxidized bacterial nanocellulose (O-BNC) is a favorable material to subdue bacterial infection because of the carboxylate content that not only has a weak antibacterial activity but also is capable of bonding electrostatically to polycationic antibacterial agents. In this study, the 2,2,6,6-Tetramethylpiperidinyloxy radical (TEMPO)-mediated oxidation of BNC was optimized to achieve high carboxylate content while retaining an acceptable tensile profile. To develop an O-BNC-based functional wound dressing, ε-poly-l-lysine (PLL) was then covalently bonded with O-BNC via 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) reaction after homogeneous distribution by ultrasonication. The antibacterial activity of the obtained wound dressing was significantly higher (p < 0.05), and no toxicity was observed. The infected full-thickness wounds of rats were healed faster (p < 0.05) covered by the dressing due to less inflammation, faster blood vessel proliferation, and epidermal layer formation. The material is an effective and promising functional dressing for the treatment of infected wounds.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Bandages; Cyclic N-Oxides; Polylysine; Rats; Wound Infection
PubMed: 35422281
DOI: 10.1016/j.carbpol.2022.119266 -
International Journal of Biological... Nov 2022The effects of ε-polylysine (ε-PL) at different concentrations (0.005 %, 0.010 %, 0.020 %, and 0.030 %) on the structure and gelling behavior of pork myofibrillar...
The effects of ε-polylysine (ε-PL) at different concentrations (0.005 %, 0.010 %, 0.020 %, and 0.030 %) on the structure and gelling behavior of pork myofibrillar protein (MP) under oxidative stress were explored. The incorporation of ε-PL significantly restrained oxidation-induced sulfhydryl and solubility losses (up to 9.72 % and 41.9 %, respectively) as well as protein crosslinking and aggregation. Compared with the oxidized control, ε-PL at low concentrations (0.005 % - 0.020 %) promoted further unfolding and destabilization of MP, while 0.030 % ε-PL led to refolding of MP and enhanced its thermal stability. The ε-PL-induced physicochemical changes favored the formation of a finer and more homogeneous three-dimensional network structure, therefore obviously enhancing the strength and water-holding capacity (WHC) of thermally induced oxidized MP gels, with the ε-PL at 0.020 % showed the greatest enhancement. This work revealed for the first time that ε-PL can significantly ameliorate the oxidation stability and gel-forming ability of meat proteins.
Topics: Gels; Meat Proteins; Muscle Proteins; Myofibrils; Oxidative Stress; Polylysine; Water
PubMed: 36030980
DOI: 10.1016/j.ijbiomac.2022.08.143 -
International Journal of Biological... Dec 2022Food preservation using biopreservative agents mainly microbial based metabolites have gained more attention in the modern food sector due to their broad spectrum... (Review)
Review
Food preservation using biopreservative agents mainly microbial based metabolites have gained more attention in the modern food sector due to their broad spectrum anti-microbial efficacy with high biocompatibility. However, the effectiveness of these biopreservatives is highly dependent on suitable formulation which will enhance the desired efficacy without affecting the nutritional value of the foods. Polylysine-actinomycete derived anti-microbial metabolite is used as biopreservative agent in various food products. This review provides a valuable insight into the formulation of polylysine with nanotechnology principles for enhanced antimicrobial efficacy against food spoilage organisms. This review highlighted the diverse methods of polylysine nanoformulation preparation. Formulation of polylysine as functionalised nanomaterials can be prepared via green science or green technology principles was extensively studied in this review. This study also revealed the methods for the determination of anti-microbial assays and biocompatibility tests in vitro and in vivo biocompatibility tests. Future prospects of nanoformulated polylysine in bio preservation can be extended to safe processing of canned and ready-to-eat food products without affecting the nutritional value of the foods.
Topics: Polylysine; Antimicrobial Cationic Peptides; Antimicrobial Peptides; Food Preservation; Nanotechnology
PubMed: 36206840
DOI: 10.1016/j.ijbiomac.2022.09.238 -
Food Chemistry Feb 2023Hexavalent chromium (Cr) owns hypertoxicity, non-biodegradability, and carcinogenicity, thus the detection of Cr is of paramount significance for environmental...
Hexavalent chromium (Cr) owns hypertoxicity, non-biodegradability, and carcinogenicity, thus the detection of Cr is of paramount significance for environmental monitoring and human health maintenance. Herein, a simple, rapid, and feasible fluorescent method based on gold nanoclusters (AuNCs) was established for determination of Cr. The AuNCs was coated by a simple and fast one-pot method using d-histidine (d-His) and polylysine (P-Lys) as stabilizers and reductants, which could be quenched by the addition of Cr owing to the aggregation of AuNCs and fluorescence resonance energy transfer (FRET) between AuNCs and Cr. Under the optimal conditions, the fluorescent sensor exhibited good linearity within 10-10000 μg/L with limit of detection of 7.2 μg/L. The developed sensor possessed favorable sensitivity and selectivity. Additionally, the proposed method also had favorable recovery with good precision and accuracy within the actual sample, including celery cabbage, rice, capsule shell, and river water.
Topics: Humans; Gold; Metal Nanoparticles; Histidine; Reducing Agents; Polylysine; Fluorescent Dyes; Water; Spectrometry, Fluorescence
PubMed: 36137372
DOI: 10.1016/j.foodchem.2022.134251 -
Biomedical Materials (Bristol, England) Aug 2023An optimal wound-healing hydrogel requires effective antibacterial properties and a favorable cell adhesion and proliferation environment. Althoughsilk fibroin (SF)...
An optimal wound-healing hydrogel requires effective antibacterial properties and a favorable cell adhesion and proliferation environment. Althoughsilk fibroin (SF) possesses inherent wound-healing properties, it lacks these essential qualities. This study aimed to fabricate a novel photo-polymerizable hydrogel by utilizing SF's wound-healing efficiency and the epsilon-poly-L-lysine (EPL) antimicrobial activity. The SF was modified with three different concentrations of glycidyl methacrylate (GMA) to obtain SF-GMA(L), SF-GMA(M), and SF-GMA(H). A methacrylated EPL (EPL-GMA) was also produced. Then, SF-GMA was mixed with EPL-GMA to produce photo-crosslinkable SF-GMA-EPL hydrogels. The SF-GMA(L)-EPL, SF-GMA(M)-EPL, and SF-GMA(H)-EPL hydrogels, fabricated with 20% EPL-GMA, demonstrated maximum antimicrobial activity and mammalian cell adhesion ability. The hydroxyl radical (•OH) scavenging efficiency of the hydrogels was tested and shown to be between 69% and 74%. These hydrogels also exhibited 60% efficiency in removing bacterial lipopolysaccharides. The water absorption ability of the hydrogels was consistent with the size of their internal pores. The hydrogels exhibited a slow degradation fashion, and their degradation products appeared cytocompatible. Finally, the elastomeric properties of the hydrogels were determined, and a storage modulus (G') of 300-600 Pa was demonstrated. In conclusion, the hydrogels created in this study possess excellent biological and physical properties to support wound healing.
Topics: Animals; Fibroins; Polylysine; Hydrogels; Wound Healing; Anti-Infective Agents; Silk; Mammals
PubMed: 37567188
DOI: 10.1088/1748-605X/acef86