Re-positioning the N,N-dimethylaminoethyloxy group at the para position of 1 to the meta position enhanced the ERα-binding affinity, and 4c showed the highest relative binding affinity (RBA: 83 vs 17β-estradiol = 100) among the tested compounds.
However, it is suggested that the correlation coefficient may be more important than the slope, since a slope ≠ 1 does not impede linking IVBA to RBA [105].
Indeed, in the Schroder et al. study [70], the bioavailability of Pb in the Pb-rich soil 9 (10,600 mg Pb/kg soil) is medium to low (RBA 20%, ABA ~ 10%), but a dose of 100 mg of soil ingested daily will release the same quantity in the body, about 0.1 mg of Pb, like the highly Pb-bioavailable but less Pb-rich soil 15 (RBA 74%, ABA ~ 37%, 3230 mg Pb/kg soil) (authors' calculation).
Table 1 Number of real operations for the symbol flipping algorithm Symbol position selection Symbol value selection RBA [5] (m+w z )w r +(w c −1)n 0 PSF [7] 7m w r −m MVA [8] m η ε η +(w c −1)n ε MVPSF [9] (7mw_{r}-n+nlog _{2} (n)) Proposed (m+w z )w r +(w c −1)n 2 p w c +(w c −1)(2 p −1) +2 p w c +(2 p −1)w c.
In contrast, octylphenol showed a 22-fold decrease in RBA (0.0029%) and nonylphenol showed a 5-fold decrease in RBA (0.0039%) when measured in adult serum.
Japanese males reached slightly less maximum knee flexion (RBA 27.9° at 151° KFA).
In 100% serum from adult men, bisphenol A showed a higher RBA (0.01%) than in serum-free medium and thus enhanced access to estrogen receptors relative to estradiol.
Leszko et al. [ 43] investigated Japanese female and male normal kinematics at even higher flexion angles and determined average maximum values for Japanese females (RBA 29.8° at 153° KFA).
After analysis of the ligands with both FIA on-line microfluidic BCD and with a traditional RBA, IC50 curves were constructed (see Fig. 5 for the on-line microfluidic BCD FIA measurements).
In serum-free medium, bisphenol A, a component of polycarbonates and of resins used to line metal food cans, showed a lower relative binding affinity (RBA; 0.006%) than octylphenol (0.072%) and nonylphenol (0.026%), which are used as surfactants in many commercial products (all RBAs are relative to estradiol, which is equal to 100%).
As the average IC50 found (IC50 of 6.38 ± 0.02) for nicotine (see Table 1) correlated well with results obtained by a traditional radioligand-binding assay (RBA; IC50 of 6.40 ± 0.01) [ 8] and low standard deviations were obtained, it was concluded that the methodology was not only accurate but also precise.
