RESUMEN
Skin injuries sustained during exercise are often irregular in shape and frequently accompanied by infections. Bacteria residing in the crevices of these wounds can lead to persistent infections. Routine wound monitoring, which requires removing the wound dressing to assess recovery, is inconvenient and increases the risk of infection. To address this, we prepared a polyvinyl alcohol/polyhydroxylated fullerenes ((PVA/PHF) hydrogel with good fluidity and photothermal antibacterial properties, which can penetrate into the crevices of irregular wounds. After the hydrogel was applied to the wound, the hydrogel was locally defined by the polycaprolactone/Chitosan (PCL/CS) membrane of in-situ electrospinning, which effectively killed bacteria, and the healing efficiency was increased by 240 % in the wound healing experiment. The PVA/PHF hydrogel exhibits excellent electrical conductivity, making it suitable for real-time monitoring of human body motion as a strain sensor. This capability provides doctors with an accurate basis for wound assessment. At the same time, the hydrogel can achieve self-healing within 1.5 s and withstand up to 2200 % tensile strain, which can be used for large-scale motion monitoring of the human body. This flowable hydrogel, capable of penetrating wound crevices, offers a dual function of both treatment and monitoring.
RESUMEN
Chronic wounds are slow to recover. During treatment, the dressing needs to be removed to check the recovery status, a process that often results in wound tears. Traditional dressings lack stretching and flexing properties and are not suitable using on wounds in joints, which require movement from time to time. In this study, we present a stretchable, flexible and breathable bandage consisting of three layers, including Mxene coating on the top, the polylactic acid/polyvinyl pyrrolidone (PLA/PVP) layer designed as Kirigami in the middle, and the f-sensor at the bottom. By the way, the f-sensor is in contact with the wound sensing real-time microenvironmental changes due to infection. When the infection intensifies, the Mxene coating at the top is utilized to enable anti-infection treatment. And Kirigami structure of PLA/PVP ensures that this bandage has stretchability, bendability, and breathability. The stretch of the smart bandage increases to 831 % compared to the original structure, and the modulus reduces to 0.04 %, which adapts extremely well to the movement of the joints and relieves the pressure on the wound. This monitoring-treatment closed-loop working mode, eliminating the need to remove dressings and avoid tissue tearing, shows a promising capability in the field of surgical wound care.
Asunto(s)
Polivinilos , Povidona , Vendajes , PoliésteresRESUMEN
ICP-MS analytical technology was used to analyze the concentration of 13 heavy metals in surface water, pore water in sediment, suspended particulate matter, and sediment of intertidalite of Tianjin. Results show that both total amount and single concentration of heavy metals vary greatly in different media, the biggest and smallest values differ by 4 or 7 magnitudes. While the variation coefficients of the contents of total metals or single metal in the same medium are less than 0.3 and 0.5 respectively except for the pore water. The average concentration of total dissolved heavy metals is 41.2 microg x L(-1), while total contents of heavy metals in original water, pore water, sediment and suspended particles are 62.7 microg x L(-1), 112.7 microg x L(-1), 262.3 mg x L(-1) and 345.0 mg x L(-1) respectively, they are similar to inland natural river but higher then those of ocean. The composition of heavy metals in different media varied greatly, metals prone to dissolve such as Mo account for more than 20% in water, but metals uneasy to dissolve mainly exist in sediment and suspended particles and absorbed by particles. Typical heavy metals, such as Zn, Cu, Pb and Cr, account for 40% - 50% in water and 50% - 80% in other media. The similarity in distribution mode of heavy metals in intertidalite and terrestrial soil suggest that they are originated from terrestrial soil that is contiguity to the sea. Notable correlativity can be seen between concentrations of all heavy metals except for Mo in sediment, which can explain the similarity of their environmental behavior, but only wake correlation between the content of organic carbon and concentrations of heavy metals in suspended particulates and sediment.
