Silanization with APTES for Controlling the Interactions Between Stainless Steel and Biocomponents: Reality vs Expectation - Biomaterials: Physics and Chemistry - page 114

O − M … O − M … O − M … O − M …

H 2 N − (CH 2 ) 3 − Si − H 2 N − (CH 2 ) 3 − Si − O − M … a = 0 O − M … a = 0 H 2 N − (CH 2 ) 3 − Si − H 2 N − (CH 2 ) 3 − Si − O − M … a = 0.5 O − M … a = 0.5

O − M … O − M … O − Si … O − Si …

O − M … O − M … O − Si … O − Si …

H 2 N − (CH 2 ) 3 − Si − H 2 N − (CH 2 ) 3 − Si − O − Si … a = 1 O − Si … a = 1 H 2 N − (CH 2 ) 3 − Si − H 2 N − (CH 2 ) 3 − Si − O − Si … a = 1.5 O − Si … a = 1.5

O − Si … O − Si … O − Si … O − Si …

O − M … O − M … O − Si … O − Si …

H 2 N − (CH 2 ) 3 − Si − H 2 N − (CH 2 ) 3 − Si − O − Si … a = 1.5 O − Si … a = 1.5 H 2 N − (CH 2 ) 3 − Si − H 2 N − (CH 2 ) 3 − Si − O − Si … a = 2 O − Si … a = 2

OH OH OH OH

Fig. 6. Possible products of APTES reaction. “M” designates metal elements of stainless steel.

0.4 0.4

a = 0 a = 1

0.3 0.3

0.2 0.2

0.1 0.1

R 2 = 0.02 R 2 = 0.53

0.0 0.0

0.0 0.1 0.2 0.3 0.4 0.0 0.1 0.2 0.3 0.4

0.4

0.4

a = 1.5 a = 2

0.3

0.3

0.2 0.2

0.1

0.1

R 2 = 0.68 R 2 = 0.80

0.0

0.0

0.0 0.1 0.2 0.3 0.4

0.0 0.1 0.2 0.3 0.4

(Fe ox + Cr ox ) / Σ org (Fe ox + Cr ox ) / Σ org

Fig. 7. Relations between molar concentrations ratioed to the sum of organic elements (Σorg)
measured by XPS at θ = 0° (data from Table 2) on native (open symbols) or silanized
stainless steel (closed symbols), as such ( ¡ , ) or further treated with coupling agent BS
( S , U ), glucose oxidase ( z , { ) or coupling agent followed by glucose oxidase ( , ).