TABLE 2.
Composite titration data for native and DNase-treated MVsa
| Ligand classb | Mean pKac | Mean LT (μM/mg [dry wt])d | Proposed functional group |
|---|---|---|---|
| n1 | 5.48 (4.8-6.0) | 0.138 (45) | Carboxyl |
| n2 | 6.91 (6.8-7.1) | 0.098 (32) | Phosphate |
| n3 | 8.32 (8.2-8.4) | 0.070 (23) | Amine |
| d1 | 5.18 (4.4-6.1) | 0.305 (38.5) | Carboxyl |
| d2 | 6.90 (6.5-7.2) | 0.242 (30.5) | Phosphate |
| d3 | 7.94 (7.8-9.0) | 0.246 (31) | Amine |
The total available surface ligand concentrations for native and DNase-treated MVs were 0.306 and 0.793 μM/mg (dry weight), respectively (DNase/native ratio of 2.5). A ratiometric comparison of DNase-treated to native MVs indicated values of 2.2 (d1/n1), 2.5 (d2/n2), and 3.5 (d3/n3). Native MVs contributed 8% (wt/wt) of the total ligand concentration of the matrix material. Data were obtained from titration analysis of three independent samples.
Based on pKa clusters in Fig. 5A and B.
Values in parentheses represent ranges for given pKa clusters. Mean pKa values were estimated using a weighted mean calculation, with the corresponding available surface ligand concentration as the weighting factor.
LT refers to site density (μM/mg [dry weight]). Values in parentheses represent the percent contribution of any functional group to the sample's total ligand concentration.