Coatings and surface treatment
on the surface. Again, we had no bacterial attachment to the catheters in this environment,” says Lange. Finally, they tested the coating on a titanium implant, which was placed beneath the skin of rats. After a week, implants with the SAFE coating had far less bacterial load than those without. The coating proved tough and resilient. What’s more, the rats’ tissues showed no sign of toxicity, indicating that the silver ions had not done their cells any harm.
Tests performed on mice further asserted the effectiveness of the silver-coated catheters in avoiding bacterial attachment.
In both models, the team found they got no bacterial attachment on the coated surfaces. They tested it against multiple bacterial species – gram-positive and gram-negative – to show efficacy across the board. Next, the researchers moved onto in vivo testing. They started by coating small catheter pieces, and inserting them into the bladders of mice.
“The bladders were inoculated with bacteria, we allowed infection to develop, then we removed the catheter pieces and quantified the amount of bacteria
Final steps and future directions At the time of writing, the researchers are close to finalising the pre-clinical aspects of their work. The final step will be to perform additional studies on pigs. This will entail inserting a catheter into each animal, inducing a urinary tract infection for seven days and then removing the device.
“If it was a coated one to begin with, we’ll then replace it with an uncoated one, to make sure that you have a head-to-head comparison within the same animal,” says Lange. “The primary outcome will be the number of bacteria in the urine, as well as the number of bacteria attached to the catheter surface.” The endgame here is to demonstrate that the technology can treat infections. Catheter-associated urinary tract infections are quite common in hospital settings, especially following prolonged usage. When a patient develops an infection of this kind, current practice is to remove the catheter, treat the patient with antibiotics, put in a new catheter and hope that the cycle doesn’t repeat itself. “Unfortunately, individuals who have to be chronically catheterised do develop these types of infections quite frequently,” says Lange. “Because our technology releases the silver over an extended period of time, there’s the potential that it could treat the infection and then prevent it from coming back.” Should the large animal studies prove successful, the researchers will start working towards 510(k) clearance in the US, which would give them the green light to commercialise their coatings. Further down the line, SAFE could have a broad array of applications, going beyond just urinary catheters. It could even be used outside the medical space, for situations in which you needed to keep a surface sterile and clean. “We can basically coat any material with this coating – metals, plastics, textiles, glass, anything,” says Lange. “It doesn’t matter what shape, size or type of material you’re talking about. In addition, it can be applied by dipping the material into the coating solution, by spraying it on or through flowing mechanisms.” While this wouldn’t be the first time silver has been used for antibiotic purposes, it could certainly wind up being one of the most effective, and as the name implies, it could also be one of the safest. ●
136 Medical Dev. Development 2022_Panacol
advertisement_85x124.indd 2 30.09.2022 14:16:29 Medical Device Developments /
www.nsmedicaldevices.com
Hamara/
Shutterstock.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164 |
Page 165 |
Page 166 |
Page 167 |
Page 168 |
Page 169 |
Page 170
