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International Journal of Bioprinting 3D printing innovations against infection

Figure 5. Innovation of 3D-bioprinted catheter to prevent infection. (A) (1) Preparation of filaments with thermoplastic polyurethane (TPU) and
tetracycline hydrochloride (TC) by 3D extrusion printing. (2) Cumulative TC release from 3D-printed catheters. (3) Microbial adherence of S. aureus to
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catheters after 24 h at 37°C. (4) Inhibition of S. aureus by catheters containing TC. Reproduced with permission from ref. . (B) (1) Schematic diagram
of drug-impregnated catheters preparation using 3D printing. (2) Cross-sections of 3D-printed coated catheters with tinidazole drug loading. (3–4)
Biofilm-destroying ability of different concentrations of secnidazole on strains of urinary tract infections and biofilm-destroying power. Reproduced
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with permission from ref. . (C) (1) Preparation of 3D-bioprinted silica scaffolds containing Lactobacillus rhamnosus. (2) Inhibition and killing of
UroPathogenic Escherichia coli (UPEC) by scaffolds. (3) Inhibition and killing of UPEC under sonication and vortex. Reproduced with permission from
ref. . (D) (1) Schematic diagram of a urinary catheter with an active biofilm removal. (2) Increased debonding of mature Proteus mirabilis crystalline
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biofilms due to increased strain rate. (3) Proof-of-concept prototype urinary catheters debonding mature P. mirabilis crystalline biofilms using inflation-
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generated strain at urinary lumen surface. Reproduced with permission from ref. .

4.2.1. Antimicrobial silver nanoparticles led by Stenzelius et al. observed that silver-coated latex
incorporation into 3D-printed catheters Foley catheters significantly reduced the risk of CAUTIs
Silver ions are extensively utilized for antimicrobial during short-term catheterization (1–3 days). Moreover,
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purposes in the realm of medical devices, particularly Davenport et al. demonstrated that the use of silver
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in the context of antimicrobial catheters. Silver ions alloy-coated 3D-printed hydrogel catheters decreased the
showcase remarkable antimicrobial efficacy, especially incidence of CAUTIs by up to 45%, particularly proving
over prolonged periods of use. This efficacy stems from effective against CAUTIs caused by E. coli, P. aeruginosa,
the ability of silver ions to eradicate a broad spectrum Enterococcus spp., and Candida. Nevertheless, it is
of microorganisms, encompassing bacteria, fungi, and crucial to note that certain studies have raised questions
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viruses (Table 2). The mechanism of action involves about the efficacy of silver coatings. Thibon et al.
the disruption of microbial cell walls, membranes, and experimentally showed that catheters coated with silver
protein structures, effectively impeding their growth and salts and hydrogels did not exhibit significant differences
reproduction. 142,143 Various forms of silver coatings, such as in preventing hospital-acquired UTIs when compared to
silver alloyed gold and silver NPs, are presently available. classical catheters. Furthermore, novel silver materials
Clinical investigations have affirmed the effectiveness of like AgNPs induce damage to bacterial structures and
silver alloy-coated antimicrobial catheters in managing increased cell membrane permeability upon delivery into
CAUTIs. For instance, a randomized controlled study the bacterial membrane, ultimately leading to cell death. A
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Volume 10 Issue 4 (2024) 135 doi: 10.36922/ijb.2338