Strategies to Prevent Bacterial Adhesion on Biomaterials - Biomimetics: Advancing Nanobiomaterials and Tissue Engineering - page 160

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Strategies to Prevent Bacterial
Adhesion on Biomaterials

Indu Bajpai 1 and Bikramjit Basu 2, *

1 Department of Materials Science and Engineering, Laboratory for
Biomaterials, Indian Institute of Technology Kanpur, Kanpur, India
2 Laboratory for Biomaterials, Materials Research Centre,
Indian Institute of Science, Bangalore, India

Abstract
Implants causing infection is a very serious concern in the biomedical fi eld. A
variety of disease causing bacteria, Enterococcus , Staphylococcus , Streptococcus and

coagulase negative Staphylococci, are antibiotic resistant and cause a serious threat
to public health worldwide. Prosthetic infection can be reduced either by modify-
ing the biomaterial surface with antibacterial agents, like Ag, ZnO and iron oxide,
or by application of external electric and magnetic fi elds. The chapter starts with
an introduction to the molecular biological structure of bacterial cells, their growth
behavior, mechanism of bacterial adhesion, and biofi lm formation on biomaterial
surface. This introductory section is followed by a discussion of bacterial adhesion
on biomaterial surface via physicochemical interactions, and molecular and cellu-
lar interactions between bacteria and surfaces. Emphasis is placed on how the bac-
terial adhesion on biomaterial surface becomes fi rmer by the selective

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bridging
function of the capsules, fi mbriae and slime. A part of this chapter discusses vari-
ous factors that infl uence bacterial adhesion such as (i) presence of serum proteins
or antibiotics, (ii) bacterial hydrophobicity, (iii) bacterial surface charge, (iv) tissue
proteins (serum) such as albumin, fi brinogen, thrombin, platelets, and (v) material
surface characteristics such as surface chemical composition, surface roughness,
surface confi guration. An important aspect of this chapter is the discussion on
the recent development of synthetic biomaterials, such as glass ceramics, HA

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− Ag

and HA ZnO composites, with good antimicrobial properties. How the addition

of Ag/ZnO needs to be tailored to have a compromise between the cytotoxicity
and antimicrobial properties is illustrated. The recent efforts towards the devel-
opment of iron oxide

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containing biocomposites are also discussed in view of the
fact that iron oxide nanoparticles are toxic for bacteria cells, whereas they are safe

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