scholarly journals Improvements in the production of purified M13 bacteriophage bio-nanoparticle

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Paolo Passaretti ◽  
Inam Khan ◽  
Timothy R. Dafforn ◽  
Pola Goldberg Oppenheimer
Keyword(s):  
Gold Standard ◽  
High Capacity ◽  
Functional Materials ◽  
Isoelectric Precipitation ◽  
M13 Bacteriophage ◽  
Precipitation Procedure ◽  
Ft Ir ◽  
Propagation Methods ◽  
The Individual ◽  
Ft Ir Spectroscopy

Abstract M13 bacteriophage is a well-established versatile nano-building block, which can be employed to produce novel self-assembled functional materials and devices. Sufficient production and scalability of the M13, often require a large quantity of the virus and thus, improved propagation methods characterised by high capacity and degree of purity are essential. Currently, the ‘gold-standard’ is represented by infecting Escherichia coli cultures, followed by precipitation with polyethylene glycol (PEG). However, this is considerably flawed by the accumulation of contaminant PEG inside the freshly produced stocks, potentially hampering the reactivity of the individual M13 filaments. Our study demonstrates the effectiveness of implementing an isoelectric precipitation procedure to reduce the residual PEG along with FT-IR spectroscopy as a rapid, convenient and effective analytic validation method to detect the presence of this contaminant in freshly prepared M13 stocks.

Differentiation of Different Mixed Listeria Strains and Also Acid-Injured, Heat-Injured, and Repaired Cells of Listeria monocytogenes Using Fourier Transform Infrared Spectroscopy

2015 ◽  
Vol 78 (3) ◽  
pp. 540-548 ◽  
Author(s):  
ESMOND NYARKO ◽  
CATHERINE DONNELLY
Keyword(s):  
Fourier Transform ◽  
Listeria Monocytogenes ◽  
Discriminant Analysis ◽  
Ir Spectroscopy ◽  
Wavelength Region ◽  
Fourier Transform Infrared ◽  
Intact Cells ◽  
Ft Ir ◽  
The Individual ◽  
Ft Ir Spectroscopy

Fourier transform infrared (FT-IR) spectroscopy was used to differentiate mixed strains of Listeria monocytogenes and mixed strains of L. monocytogenes and Listeria innocua. FT-IR spectroscopy was also applied to investigate the hypothesis that heat-injured and acid-injured cells would return to their original physiological integrity following repair. Thin smears of cells on infrared slides were prepared from cultures for mixed strains of L. monocytogenes, mixed strains of L. monocytogenes and L. innocua, and each individual strain. Heat-injured and acid-injured cells were prepared by exposing harvested cells of L. monocytogenes strain R2-764 to a temperature of 56 ± 0.2°C for 10 min or lactic acid at pH 3 for 60 min, respectively. Cellular repair involved incubating aliquots of acid-injured and heat-injured cells separately in Trypticase soy broth supplemented with 0.6% yeast extract for 22 to 24 h; bacterial thin smears on infrared slides were prepared for each treatment. Spectral collection was done using 250 scans at a resolution of 4 cm−1 in the mid-infrared wavelength region. Application of multivariate discriminant analysis to the wavelength region from 1,800 to 900 cm−1 separated the individual L. monocytogenes strains. Mixed strains of L. monocytogenes and L. monocytogenes cocultured with L. innocua were successfully differentiated from the individual strains when the discriminant analysis was applied. Different mixed strains of L. monocytogenes were also successfully separated when the discriminant analysis was applied. A data set for injury and repair analysis resulted in the separation of acid-injured, heat-injured, and intact cells; repaired cells clustered closer to intact cells when the discriminant analysis (1,800 to 600 cm−1) was applied. FT-IR spectroscopy can be used for the rapid source tracking of L. monocytogenes strains because it can differentiate between different mixed strains and individual strains of the pathogen.

Composition Determination of Multicomponent Organic Aerosols by On-Line FT-IR Spectroscopy

2002 ◽  
Vol 56 (11) ◽  
pp. 1429-1435 ◽  
Author(s):  
Cindy L. DeForest ◽  
Jun Qian ◽  
Roger E. Miller
Keyword(s):  
Ir Spectroscopy ◽  
Organic Aerosols ◽  
Aerosol Composition ◽  
Composition Determination ◽  
Polycyclic Aromatic ◽  
On Line ◽  
Ft Ir ◽  
The Individual ◽  
Study Laboratory ◽  
Ft Ir Spectroscopy

A new approach is reported for determining the composition of multicomponent organic aerosols using FT-IR spectroscopy. In this study, laboratory-generated aerosol particles are thermally evaporated and the resulting vapor is immediately analyzed using FT-IR spectroscopy. The composition of the aerosol is determined by fitting the vapor spectrum to a linear combination of reference spectra of the individual components. Application of the method to the detection of polycyclic aromatic hydrocarbons, changes in aerosol composition, and analysis of diesel fuel is demonstrated.

scholarly journals The Preparation, Thermal Properties, and Fire Property of a Phosphorus-Containing Flame-Retardant Styrene Copolymer

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 127 ◽  
Author(s):  
Yu Sun ◽  
Yazhen Wang ◽  
Li Liu ◽  
Tianyuan Xiao
Keyword(s):  
Thermal Properties ◽  
Thermogravimetric Analysis ◽  
Flame Retardant ◽  
Oxygen Index ◽  
Limiting Oxygen Index ◽  
Chemical Structures ◽  
1H Nuclear Magnetic Resonance ◽  
Phosphorus Containing ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

A 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) acrylate, (6-oxidodibenzo [c,e][1,2] oxaphosphinin-6-yl) methyl acrylate (DOPOAA), has been prepared. Copolymers of styrene (St) and DOPOAA were prepared by emulsion polymerization. The chemical structures of copolymers containing levels of DOPOAA were verified using Fourier transform infrared (FT-IR) spectroscopy and 1H nuclear magnetic resonance (1H-NMR) spectroscopy. The thermal properties and flame-retardant behaviors of DOPO-containing monomers and copolymers were observed using thermogravimetric analysis and micro calorimetry tests. From thermogravimetric analysis (TGA), it was found out that the T5% for decomposition of the copolymer was lower than that of polystyrene (PS), but the residue at 700 °C was higher than that of PS. The results from micro calorimetry (MCC) tests indicated that the rate for the heat release of the copolymer combustion was lower than that for PS. The limiting oxygen index (LOI) for combustion of the copolymer rose with increasing levels of DOPOAA. These data indicate that copolymerization of the phosphorus-containing flame-retardant monomer, DOPOAA, into a PS segment can effectively improve the thermal stability and flame retardancy of the copolymer.

Multiscale exploration of hydrocarbons adsorption and hopping through the ZSM-5 channels - from Monte Carlo modelling to experiment

2021 ◽  
Author(s):  
Maciej Strzempek ◽  
Karolina A. Tarach ◽  
Kinga Góra-Marek ◽  
Fernando Rey ◽  
Miguel Palomino ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Ir Spectroscopy ◽  
Aliphatic Hydrocarbons ◽  
Adsorption Studies ◽  
Ft Ir ◽  
Gravimetric Adsorption ◽  
Hydrocarbons Adsorption ◽  
Ft Ir Spectroscopy

Abstract In this article the results of the statistical MC modelling corroborated by the FT-IR spectroscopy and gravimetric adsorption studies of the low aliphatic hydrocarbons in ZSM-5 (Si/Al =28 or...

scholarly journals Kinetical Study, Thermo-Mechanical Characteristics and Recyclability of Epoxidized Camelina Oil Cured with Antagonist Structure (Aliphatic/Aromatic) or Functionality (Acid/Amine) Hardeners

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2503
Author(s):  
Chiara Di Mauro ◽  
Aratz Genua ◽  
Alice Mija
Keyword(s):  
Disulfide Bonds ◽  
Mechanical Characteristics ◽  
Dicarboxylic Acids ◽  
Thermomechanical Properties ◽  
Chemical Recycling ◽  
Camelina Oil ◽  
Ft Ir ◽  
Tan Δ ◽  
The Individual ◽  
First Time

In an attempt to prepare sustainable epoxy thermosets, this study introduces for the first time the idea to use antagonist structures (aromatic/aliphatic) or functionalities (acid/amine) as hardeners to produce reprocessable resins based on epoxidized camelina oil (ECMO). Two kinds of mixtures were tested: one combines aromatic/aliphatic dicarboxylic acids: 2,2′-dithiodibenzoic acid (DTBA) and 3,3′-dithiodipropionic acid (DTDA); another is the combination of two aromatic structures with acid/amine functionality: DTBA and 4-aminophenyl disulfide (4-AFD). DSC and FT-IR analyses were used as methods to analyze the curing reaction of ECMO with the hardeners. It was found that the thermosets obtained with the dual crosslinked mechanism needed reduced curing temperatures and reprocessing protocols compared to the individual crosslinked thermosets. Thanks to the contribution of disulfide bonds in the network topology, the obtained thermosets showed recycling ability. The final thermomechanical properties of the virgin and mechanical reprocessed materials were analyzed by DMA and TGA. The obtained thermosets range from elastomeric to rigid materials. As an example, the ECMO/DTBA704-AFD30 virgin or reprocessed thermosets have tan δ values reaching 82–83 °C. The study also investigates the chemical recycling and the solvent resistance of these vitrimer-like materials.

scholarly journals Vibrational Spectroscopic Investigation of Blood Plasma and Serum by Drop Coating Deposition for Clinical Application

2021 ◽  
Vol 22 (4) ◽  
pp. 2191
Author(s):  
Jing Huang ◽  
Nairveen Ali ◽  
Elsie Quansah ◽  
Shuxia Guo ◽  
Michel Noutsias ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Outer Ring ◽  
Imaging Method ◽  
Fluorescence Lifetime Imaging ◽  
Drying Process ◽  
Vibrational Signal ◽  
Coating Deposition ◽  
Ft Ir ◽  
Sample Droplet ◽  
Ft Ir Spectroscopy

In recent decades, vibrational spectroscopic methods such as Raman and FT-IR spectroscopy are widely applied to investigate plasma and serum samples. These methods are combined with drop coating deposition techniques to pre-concentrate the biomolecules in the dried droplet to improve the detected vibrational signal. However, most often encountered challenge is the inhomogeneous redistribution of biomolecules due to the coffee-ring effect. In this study, the variation in biomolecule distribution within the dried-sample droplet has been investigated using Raman and FT-IR spectroscopy and fluorescence lifetime imaging method. The plasma-sample from healthy donors were investigated to show the spectral differences between the inner and outer-ring region of the dried-sample droplet. Further, the preferred location of deposition of the most abundant protein albumin in the blood during the drying process of the plasma has been illustrated by using deuterated albumin. Subsequently, two patients with different cardiac-related diseases were investigated exemplarily to illustrate the variation in the pattern of plasma and serum biomolecule distribution during the drying process and its impact on patient-stratification. The study shows that a uniform sampling position of the droplet, both at the inner and the outer ring, is necessary for thorough clinical characterization of the patient’s plasma and serum sample using vibrational spectroscopy.

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