A methodological approach for the thermal stability and stress exposure studies of a model antibody

Photochemistry on the Space Station—Antibody Resistance to Space Conditions after Exposure Outside the International Space Station

“…Long-time exposure to real space conditions during the EXPOSE-R2 mission were evaluated on freeze-dried Ab in both covalently immobilized format (labelled "G" for grafted) and insolution Ab format (free anti-HRP Ab labelled "F" for free). The immobilization strategy, the freeze-drying optimized procedure, the A2HRP validated protocol were detailed elsewhere , Coussot et al, 2018a, Coussot et al, 2018b, Coussot et al, 2018c. The freeze-drying stock solution was freshly prepared and was composed of 1.05 g of citric acid (0.1M), 38.75 mg of His (5 mM), 52.5 mg of Arg (5 mM) in a final volume of 50 mL of water and adjusted to pH 6.5 with NaOH (10M) before adding 10 µL of Tween®20.…”

“…In each inactivated BSA well, a volume of 100 µL of the anti-HRP Ab in the freeze-drying solution was mixed with 20 µL of a freshly prepared sucrose solution (5g.L -1 in water). The wells were placed within the homemade pre-frozen aluminium block designed by our group, and kept frozen by adding liquid nitrogen to follow the optimized freeze-drying procedure (Coussot et al, 2018c) as described in the section…”

“…The Lower Limit of Quantification (LLOQ) corresponds to 1.40 ± 0.18% of the initial rate of active Ab. The A2HRP method was successfully used in optimizing freeze-drying conditions to better preserve the Ab functionality, notwithstanding its format (Coussot et al, 2018c), and in evaluating the Ab resistance under various stressful environments , Coussot et al, 2018c.…”

“…In this work, we first summarize our experiment (see also Vigier et al 2013), which was part of the Photochemistry on the Space Station (PSS) project (Cottin et al, 2015) and the analytical developments we conducted prior to the final analyses performed on the samples few weeks after their return to Earth (Coussot et al 2018a(Coussot et al , 2018b(Coussot et al and 2018c. Both formats, free anti-HRP Ab and anti-HRP Ab immobilized onto a surface, have been conditioned into a homemade sample holder unit and installed outside the International Space Station (ISS) on the EXPOSE-R2 platform.…”

Photochemistry on the Space Station—Aptamer Resistance to Space Conditions: Particles Exposure from Irradiation Facilities and Real Exposure Outside the International Space Station

“…Particle irradiation effects were evaluated on both freeze-dried 49merYm3'F aptamer and fluorescein dye. One hundred microliters of 49merYm3'F aptamer or fluorescein solution at 500 nM in ultrapure water (dilution by 1/40 from a stock solution freshly prepared at 20 µM from aptamer commercial vial) were put into MaxiSorp™ wells (commercial or home-designed well format) and freeze-dried according to a protocol optimized for the freeze-drying of small volume of reactants (Coussot et al, 2018a). Briefly, MaxiSorp™ wells were put into a homemade aluminium holder, and liquid nitrogen was added to freeze the samples.…”