Study On Skin Penetration And In Vivo Accumulation Of Nano - Silver Antibacterial Dressing

Nano Silver is defined as Ag particles having one or more dimensions in the order of 100 nm or less.Due to the vast surface area of nano silver, its physical, chemical and biological properties has changed dramatically, showing characteristic unique anti-bacterial, fungal, viral and anti-inflammatory. So nano-silver products are widely used in biomedical(including diagnosis, treatment, drug delivery systems, medical devices coated and personal care products), home appliances, clothing, sporting goods and food contact materials. The antimicrobial Medical Dressings mainly composed of an antibacterial fabric, This fabric is generally medical gauze or non-woven medical gauze, Nano Silver(NOS) attached on this fabric. Using molecular micro-nano patented technology to produce NOS fine particle. It have broad-spectrum, strong, long-term role in the bactericidal. none drug resistance and effect enhancement when encountering water. achieves the high efficacy,broad-spectrum antibacterial action without containing antibiotics.It can improve the microcirculation and reduce scar formation, also have good hydrophilic character. No reaction on the human body to stimulate and easy to use.It widely applied to the clinical burn unit, operating room, emergency surgery, surgery, obstetrics and gynecology, dermatology, plastic surgery, oral surgery and many other departments.Especially apply to a large number of open wounds, which caused by disasters, wars and other emergencies. Quickly to deal with wounds and real-time control of wound infection. Wounds caused by accidents can be anti-infective treatment immediately in tourism, sports, construction sites and field work.The State Food and Drug Administration issued "on the medical devices nanobiomaterials Categories adjustment notice"(SFDA [2006] No. 146) in august 2012.Nanobiomaterials medical devices(such as nano silver metallic materials for medical devices) clearly is the third class medical devices.Therefore ts biological safety assessment and toxicology risk assessment is necessary. In order to study nano-silver accumulation in rats situation(30% body surface area) and penetration in skin(4cm2) through making the model of deep partial thickness burns.The results of bioaccumulation studies in rats showed that, in the low-dose group and middle dose group,silver content was lower than the average silver content of the test line 5 ng / g in the blood, pancreas, liver, kidney, spleen, heart, lungs at14 days after a single dose; in the high dose group, the content was lower than the average silver content of the test line 5 ng / g in the liver, kidneys, spleen, heart, lungs.pancreas close to the line. The rest of the skin, brain, feces in each dose group were silver residue.At 28 days after the end of multiple doses, each dose group the silver content of the new skin in 20 ng / g or so. In the low-dose group and middle dose group,silver content was lower than the average silver content of the test line 5 ng / g in the liver, kidney, spleen, heart, lungs; pancreas close to the line; in the high dose group, the content was lower than the average silver content of the test line 5 ng / g in the blood, pancreas,liver;other organs had some residual(11.58-62.42 ng / g). The rest of the brain and feces in each dose group were silver residues.The results of penetration in rat skin studies showed that silver content of blood and organs were less than 30 ng / g, and did not show a significant dose-dependent and time-dependent manner. The overall trend was that silver content of the skin increased with longer time of administration;silver content reduced, along with increased skin depth in the normal low-dose group, the normal high-dose group, low-dose group burn, burn high-dose group.