Aggregation of Synthetic Gene Delivery Vectors Enhance the Cellular Association and Uptake for in vitro Transfection

Development of safe and efficient synthetic gene delivery vectors is hampered with limited understanding the fundamental correlation of physicochemical properties of the vectors with their biological activities. Five major barriers contributing to poor transfection efficiency of synthetic vectors include cellular association, endosomal escape, intracellular trafficking, nuclear translocation and transcription of exogenous genes. In this study, the correlation of physicochemical properties of polymer-based synthetic gene delivery vectors (polyplexes) with cellular association as the first barrier for in vitro transfection was investigated. Polyethylene oxide block copolymer with poly(2-(dimethylamino)ethyl methacryate) (PEO-b-pDMAEMA) was chosen as the model in this study. Cellular association and transfection efficiency of block copolymer complexes were studied in Neuro2A cells. Quantitative real time polymerase chain reaction (PCR) was applied to elucidate the cellular association of polyplexes. Physicochemical properties of the vectors including size and surface charge were characterized using light scattering measurements. Formation of aggregate was found as the major indication for high cellular association and uptake for in vitro transfection.Singapore-MIT Alliance (SMA

Understanding the Induced Self-Assembly System Between PEO-b-PAA and Iron

The induced self-assembly phenomenon between PEO-b-PAA and Fe(II) was investigated. It was revealed that the electrostatic interaction between Fe(II) in the form of green rust (GR²⁺) particles and the COO- groups from the PAA backbone at pH 7 causes the formation of stable aggregates with Dh~156 nm. While it is stable at pH 7, the induced self-assembly structure, however, is disordered during the transformation of GR²⁺ into Fe₃O₄. The pH increment and the oxidation process itself were found to affect the stability.Singapore-MIT Alliance (SMA

Advanced Functional Materials from Nanopolysaccharides

Polysaccharide is a type of carbohydrate molecules composed of long polymeric chains with monosaccharide units as building blocks covalently bound together by glycosidic linkages. The typical polysaccharides in nature are cellulose, chitin, and starch, which commonly exist in the plants, animals, microorganisms, and bacteria. Derived from the strong intra-and inter-molecular hydrogen bonds, the crystalline and amorphous regions by the ordered arrangement and assembly of the linear and highly branched polymeric chains constitute the microstructures of these polysaccharides. Nanopolysaccharides can be produced by the partial or complete removal of amorphous regions, which is a kind of novel materials with the preservation of crystalline region and possesses the nanometer scale (< 100 nm) at least one dimension. The typical nanopolysaccharides include the highly crystalline cellulose nanocrystal, chitin

Observation of WWWWWW Production in pppp Collisions at s\sqrt s =13 TeV with the ATLAS Detector

International audienceThis Letter reports the observation of $WWW$ production and a measurement of its cross section using 139 fb$^{-1}$ of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from $WWW$ production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive $WWW$ production cross section is measured to be $820 \pm 100\,\text{(stat)} \pm 80\,\text{(syst)}$ fb, approximately 2.6 standard deviations from the predicted cross section of $511 \pm 18$ fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy

Observation of WWWWWW Production in pppp Collisions at s\sqrt s =13 TeV with the ATLAS Detector

International audienceThis Letter reports the observation of $WWW$ production and a measurement of its cross section using 139 fb$^{-1}$ of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from $WWW$ production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive $WWW$ production cross section is measured to be $820 \pm 100\,\text{(stat)} \pm 80\,\text{(syst)}$ fb, approximately 2.6 standard deviations from the predicted cross section of $511 \pm 18$ fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy

Observation of WWWWWW Production in pppp Collisions at s\sqrt s =13 TeV with the ATLAS Detector

International audienceThis Letter reports the observation of $WWW$ production and a measurement of its cross section using 139 fb$^{-1}$ of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from $WWW$ production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive $WWW$ production cross section is measured to be $820 \pm 100\,\text{(stat)} \pm 80\,\text{(syst)}$ fb, approximately 2.6 standard deviations from the predicted cross section of $511 \pm 18$ fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy

Observation of WWWWWW Production in pppp Collisions at s\sqrt s =13 TeV with the ATLAS Detector

International audienceThis Letter reports the observation of $WWW$ production and a measurement of its cross section using 139 fb$^{-1}$ of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from $WWW$ production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive $WWW$ production cross section is measured to be $820 \pm 100\,\text{(stat)} \pm 80\,\text{(syst)}$ fb, approximately 2.6 standard deviations from the predicted cross section of $511 \pm 18$ fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy

Observation of WWWWWW Production in pppp Collisions at s\sqrt s =13 TeV with the ATLAS Detector

International audienceThis Letter reports the observation of $WWW$ production and a measurement of its cross section using 139 fb$^{-1}$ of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from $WWW$ production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive $WWW$ production cross section is measured to be $820 \pm 100\,\text{(stat)} \pm 80\,\text{(syst)}$ fb, approximately 2.6 standard deviations from the predicted cross section of $511 \pm 18$ fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy