af4 device  (Postnova Analytics)

Journal: Journal of Virology

Article Title: Structural Studies Reveal that Endosomal Cations Promote Formation of Infectious Coxsackievirus A9 A-Particles, Facilitating RNA and VP4 Release

doi: 10.1128/jvi.01367-22

Figure Lengend Snippet: AF4 allows separation of the heterogeneous CVA9 virion population generated by 0.01% faf-BSA and endosomal ion treatments. (A) Two independent AF4 fractograms of untreated CVA9. (B) AF4 fractogram of CVA9 after 1-h treatment with 0.01% faf-BSA at 37°C. (C) AF4 fractogram of CVA9 after 3-h treatment with 0.01% faf-BSA at 37°C. (D) AF4 fractogram of CVA9 after 1-h treatment in endosomal ion environment at 37°C. (E) AF4 fractogram of CVA9 after 3-h treatment in endosomal ion environment at 37°C. (F) AF4 fractogram of CVA9 after combined treatment (0.01% faf-BSA in endosomal ionic environment) for 1 h at 37°C. In all panels, the x axis indicates time (1-mL fractions were collected at the rate of 0.5 mL/min); the y axis on the left shows light scattering (black or gray lines) and on the right the hydrodynamic radius is shown, as measured by online dynamic light scattering detector (black dots). The vertical dashed line on the left indicates the peak for intact particles and on the right the peak for expanded particles. AF4 fractions used for MS analysis are indicated by red boxes. The light scatter absorbance on all the fractograms was normalized to the highest light scatter absorbance peak, which is found in panel F.

Article Snippet: The AF4 device was coupled to an Optilab refractive index detector (Wyatt Technology), DAWN multiangle light scattering detector (MALS) with 18 angles (Wyatt Technology), online dynamic light scattering detector embedded in one of the DAWN angles (Wyatt Technology), and a UV detector (Agilent) set at 280 nm.

Techniques: Generated

Journal: Journal of Virology

Article Title: Structural Studies Reveal that Endosomal Cations Promote Formation of Infectious Coxsackievirus A9 A-Particles, Facilitating RNA and VP4 Release

doi: 10.1128/jvi.01367-22

Figure Lengend Snippet: AF4 results ^a

Article Snippet: The AF4 device was coupled to an Optilab refractive index detector (Wyatt Technology), DAWN multiangle light scattering detector (MALS) with 18 angles (Wyatt Technology), online dynamic light scattering detector embedded in one of the DAWN angles (Wyatt Technology), and a UV detector (Agilent) set at 280 nm.

Techniques:

Journal: Analytical and Bioanalytical Chemistry

Article Title: Optimization of hyphenated asymmetric flow field-flow fractionation for the analysis of silver nanoparticles in aqueous solutions

doi: 10.1007/s00216-021-03647-3

Figure Lengend Snippet: Summary of the hyphenated AF4 experimental design. Experiments were conducted in single runs or duplicates

Article Snippet: The separation protocol comprised six consecutive steps, each characterized by its individual duration and applied cross-flow rate ( V x ) as shown in the example of Table S . For the evaluation of the quality of the separation and the characterization of the AgNP fractions’ optical properties, UV/Vis spectra were recorded using a Shimadzu SPD-M10Avp photodiode array detector (PDA, graphical abstract) linked to the Eclipse AF4 device with 0.25-mm ID PEEK tubing and controlled with a SCL-10Avp unit via the LCsolution software 1.03 SP3 (Shimadzu).

Techniques:

Journal: Analytical and Bioanalytical Chemistry

Article Title: Optimization of hyphenated asymmetric flow field-flow fractionation for the analysis of silver nanoparticles in aqueous solutions

doi: 10.1007/s00216-021-03647-3

Figure Lengend Snippet: Size characterization of AgNP_LA in batch and in AF4-UV/Vis-DLS system. Results obtained with the ZetaSizer Nano-ZS for the hydrodynamic diameter d H , polydispersity index PdI , and zeta-potential ζ . Parenthesized values were determined ca. 4 months after purchasing the AgNPs; all other values were determined directly after delivery. AF4 experiments were conducted within 2 months after AgNP delivery. Values shown in the table for 1:1 AgNP_LA mixtures were acquired with the best experimental conditions

Article Snippet: The separation protocol comprised six consecutive steps, each characterized by its individual duration and applied cross-flow rate ( V x ) as shown in the example of Table S . For the evaluation of the quality of the separation and the characterization of the AgNP fractions’ optical properties, UV/Vis spectra were recorded using a Shimadzu SPD-M10Avp photodiode array detector (PDA, graphical abstract) linked to the Eclipse AF4 device with 0.25-mm ID PEEK tubing and controlled with a SCL-10Avp unit via the LCsolution software 1.03 SP3 (Shimadzu).

Techniques:

Journal: Analytical and Bioanalytical Chemistry

Article Title: Optimization of hyphenated asymmetric flow field-flow fractionation for the analysis of silver nanoparticles in aqueous solutions

doi: 10.1007/s00216-021-03647-3

Figure Lengend Snippet: Fractograms and hydrodynamic diameter of a 1:1 mixture of 20-nm and 80-nm AgNP_LA acquired with V x = 0.5 mL/min and 0.05% v/v Mucasol as carrier solution. Black color refers to a mixture prepared in ultrapure water; red color refers to the preparation in fjord water and injection into the AF4 system 20 min after preparation

Article Snippet: The separation protocol comprised six consecutive steps, each characterized by its individual duration and applied cross-flow rate ( V x ) as shown in the example of Table S . For the evaluation of the quality of the separation and the characterization of the AgNP fractions’ optical properties, UV/Vis spectra were recorded using a Shimadzu SPD-M10Avp photodiode array detector (PDA, graphical abstract) linked to the Eclipse AF4 device with 0.25-mm ID PEEK tubing and controlled with a SCL-10Avp unit via the LCsolution software 1.03 SP3 (Shimadzu).

Techniques: Injection

Journal: ACS omega

Article Title: Adeno-associated Virus Virus-like Particle Characterization via Orthogonal Methods: Nanoelectrospray Differential Mobility Analysis, Asymmetric Flow Field-Flow Fractionation, and Atomic Force Microscopy.

doi: 10.1021/acsomega.1c01443

Figure Lengend Snippet: Figure 1. Scheme of the two analytical focuses of this study. (a) Empty and filled AAV8 VLP particles are analyzed via nES GEMMA and AFM. (b) AF4 liquid-phase separation enables AAV8 VLP oligomer analysis by means of nES GEMMA and AFM after fractionation.

Article Snippet: The capillary is manually cut and tapered with a homebuilt grinding machine based on the work of Tycova et al.15 AF4 experiments were performed on an Agilent 1200 system (Agilent Technologies, Santa Clara, CA, USA, auto sampler, pump, and detector), which consisted of an auto sampler, HPLC pumps, an AF4 separation device (Wyatt Technology, Santa Barbara, CA, USA), and a fluorescence detector (λex/em = 280/340 nm).

Techniques: Gas Phase Electrophoretic Molecular Mobility Analysis, Fractionation

Journal: ACS omega

Article Title: Adeno-associated Virus Virus-like Particle Characterization via Orthogonal Methods: Nanoelectrospray Differential Mobility Analysis, Asymmetric Flow Field-Flow Fractionation, and Atomic Force Microscopy.

doi: 10.1021/acsomega.1c01443

Figure Lengend Snippet: Figure 2. Implications of the buffer exchange treatment. (a) nES GEMMA spectra of the sample before (black trace) and after (red trace) desalting. Nonvolatile salts and other components (3−15 nm) are drastically reduced. The inset shows the shift toward small EM diameter of the AAV8 VLP’s peak. (b) AF4 fractogram of the sample with (red trace) or without (blue trace) a buffer exchange procedure. Both nES GEMMA spectra (a) and (b) show reduced signal intensity for the AAV8 VLP’s peak due to sample loss during the desalting treatment.

Article Snippet: The capillary is manually cut and tapered with a homebuilt grinding machine based on the work of Tycova et al.15 AF4 experiments were performed on an Agilent 1200 system (Agilent Technologies, Santa Clara, CA, USA, auto sampler, pump, and detector), which consisted of an auto sampler, HPLC pumps, an AF4 separation device (Wyatt Technology, Santa Barbara, CA, USA), and a fluorescence detector (λex/em = 280/340 nm).

Techniques: Gas Phase Electrophoretic Molecular Mobility Analysis

Journal: ACS omega

Article Title: Adeno-associated Virus Virus-like Particle Characterization via Orthogonal Methods: Nanoelectrospray Differential Mobility Analysis, Asymmetric Flow Field-Flow Fractionation, and Atomic Force Microscopy.

doi: 10.1021/acsomega.1c01443

Figure Lengend Snippet: Figure 4. Stressing procedure and fractionation of the sample. (a) AF4 fractogram of control (blue trace) and heat/mechanical-stressed (magenta trace) sample. (b) The red vertical lines mark the collected fractions: 16.5−19.2 min monomer fraction; 19.2−20.6 min dimer and trimer fraction; 20.6−25.0 min higher oligomeric fraction.

Article Snippet: The capillary is manually cut and tapered with a homebuilt grinding machine based on the work of Tycova et al.15 AF4 experiments were performed on an Agilent 1200 system (Agilent Technologies, Santa Clara, CA, USA, auto sampler, pump, and detector), which consisted of an auto sampler, HPLC pumps, an AF4 separation device (Wyatt Technology, Santa Barbara, CA, USA), and a fluorescence detector (λex/em = 280/340 nm).

Techniques: Fractionation, Control

Journal: ACS omega

Article Title: Adeno-associated Virus Virus-like Particle Characterization via Orthogonal Methods: Nanoelectrospray Differential Mobility Analysis, Asymmetric Flow Field-Flow Fractionation, and Atomic Force Microscopy.

doi: 10.1021/acsomega.1c01443

Figure Lengend Snippet: Figure 5. nES GEMMA spectra and AFM images of the three fractions collected with the AF4 technique (see Figure 4b). (a, b) Monomer (M) fraction; (c, d) dimer (D) and trimer (T) fraction; and (e, f) higher oligomeric (O) fraction. nES GEMMA spectra compare signals obtained for VLP-containing samples (red traces) and blanks recorded for a NH4OAc blank (black traces), respectively. nES GEMMA signals below 20 nm EM diameter putatively correspond to incompletely removed, aggregating AF4 buffer components. In (f), the arrow indicates an AAV8 VLP higher oligomer with a height of 35 nm.

Article Snippet: The capillary is manually cut and tapered with a homebuilt grinding machine based on the work of Tycova et al.15 AF4 experiments were performed on an Agilent 1200 system (Agilent Technologies, Santa Clara, CA, USA, auto sampler, pump, and detector), which consisted of an auto sampler, HPLC pumps, an AF4 separation device (Wyatt Technology, Santa Barbara, CA, USA), and a fluorescence detector (λex/em = 280/340 nm).

Techniques: Gas Phase Electrophoretic Molecular Mobility Analysis