Fig 1.
Scheme of the systems investigated in this work.
a) Antibody conjugated nanoparticle with antibodies covalently bonded to the nanoparticle. b) Antibody conjugated nanoparticle with antibodies bonded through streptavidin-biotin. *) Scheme of the coarse grain model of the antibody b12 (cyan) having a 50 units spacer and an antigen gp120 bound (blue).
Fig 2.
Captured antigen as a function of antibody surface coverage on AcNP with antibodies covalently conjugated.
The different colors represent different antibody/antigen Kd values. A) Antigen bulk concentration = 20 pM and spacer of 50 monomers. B) Antigen bulk concentration = 20 pM and no spacer. C) Antigen bulk concentration = 100 nM and spacer of 50 monomers. D) Antigen bulk concentration = 100 nM and no spacer.
Fig 3.
Number of unbound antibodies (0 ant.), antibodies bound to one antigen (1 ant.), antibodies bound to two antigens (2 ant.) and total active antibodies (total) on surface, as a function of the surface coverage in a covalently bonded AcNP.
A) Antigen bulk concentration = 100 nM, 50 monomer spacer, Kd = 10−9 M. B) Antigen bulk concentration = 100 nM, 50 monomer spacer, Kd = 10−11 M.
Fig 4.
Averaged center of mass of unbound antibodies (0 ant.), antibodies bound to one antigen (1 ant.), antibodies bound to two antigens (2 ant.) as a function of the surface coverage. A) Antigen bulk concentration = 100 nM, spacer 50 monomers, Kd = 10−9 M. B) Antigen bulk concentration = 100 nM, spacer 50 monomers, Kd = 10−11 M.
Fig 5.
Captured antigen per area as a function of antibody surface coverage.
Covalent bonded AcNP, spacer 50 monomers, Kd = 10−9 M. A) For different antigen bulk concentrations. AcNP radius = 50 nm. B) For different AcNP radius. Inset in panel B) are same data but the captured antigen normalized by the area of the NP. Red and black dashed lines, in the inset, represent the ideal situation of all the antibodies bound to two or one antigen respectively. Antigen bulk concentration = 100 nM. Triangle symbols represent the set of conditions used in this paper for the rest of the calculations.
Fig 6.
Captured antigen as a function of the antibody surface coverage on AcNP conjugated through streptavidin/biotin.
The different colors represent different antibody-antigen Kd values. A) Bulk mix concentration = 20 pM antigen/10 pM antibody and spacer of 50 monomers. B) Bulk mix concentration = 20 pM antigen/10 pM antibody and no spacer. C) Bulk mix concentration = 200 nM antigen/100 nM antibody and spacer of 50 monomers. D) Bulk mix concentration = 200 nM antigen/100 nM antibody and no spacer.
Fig 7.
Amount of antibody unbound (0 ant.), antibody bound to one antigen (1 ant.), antibody bound to two antigens (2 ant.) and total antibody (total) on surface as a function of the streptavidin surface coverage. A) Bulk mix concentration = 200 nM antigen/100 nM antibody, spacer 50 monomers, Kd = 10−9 M. B) Bulk mix concentration = 200 nM antigen/100 nM antibody, spacer 50 monomers, Kd = 10−11 M.
Fig 8.
Captured antigen per unit area as a function of antibody surface coverage.
Streptavidin conjugated AcNP, spacer 50 monomers, Kd = 10−9 M. A) For different antigen bulk concentrations. AcNP radius = 50 nm. B) For different AcNP radius. Inset in panel B) are same data but the captured antigen normalized by the area of the NP. Red and black dashed lines, in the inset, represent the ideal situation of all the antibodies bound to two or one antigen respectively. Bulk concentration mix = 100 nM antibody: 200nM antigen. Triangle symbols represent the set of conditions used in this paper for the rest of the calculations.