Preparation And Properties Of Sodium Alginate-based Antibacterial Medical Hydrocolloid Dressing

Hydrocolloid dressings can permanently absorb wound exudate to maintain moist environment of wound and accelerate healing process.It is widely used in normal injury wound,surgical wounds and chronic wounds.The liquid absorption performance of hydrocolloid layer directly determines the liquid absorbing property of the hydrocolloid dressings.Sodium alginate is a hydrophilic viscous polysaccharide with good gelling performance and liquid absorbing property.Therefore,sodium alginate can be compounded with thermoplastic elastomer to prepare a hydrocolloid layer with high liquid absorption property.In the first part of this thesis,water-absorbing particles with high liquid absorption properties were synthesized using sodium alginate,then hydrocolloid dressings were prepared by combining absorption properties with hot melt pressure sensitive adhesive.The different content of water absorbing particles in sodium alginate based hydrocolloid dressings was studied and the water absorbing ability was compared with commercially available hydrocolloid dressings.The internal porous structure of the hydrocolloid dressing was characterized by SEM.The tensile strength and elongation properties demonstrated the good mechanical properties of the hydrocolloid dressing.The comfort,peel strength and persistent adhesivity were also characterized.In vitro cell toxicity and hemolysis experiments have demonstrated the good biocompatiblity of hydrocolloid dressings.Wound infection seriously affects the healing process of wound,and even threatens life when it is serious.Hydrocolloid dressings have good bacteriostatic properties and prevent bacteria from re-invading wound,but they are not suitable for wounds that have infected wounds or are at risk of potential infection.The second part of this thesis is based on the first part of the work by adding nano zinc oxide,gentamicin and bromoalkane quaternized polyethyleneimine(QPEI)as an antibacterial agent to give excellent antibacterial property to hydrocolloid dressings.performance.The results of antibacterial experiments show that the hydrocolloid dressing with 3%of nano zinc oxide had good antibacterial effect against Escherichia coli and Staphylococcus aureus at 10 mg/mL.The hydrocolloid dressing with 3%gentamicin had good antibacterial effect on E.coli at 3 mg/mL,and had good antibacterial effect against S.aureus at 10 mg/mL.The hydrocolloid dressing with 3%bromohexane quatemized polyethyleneimine(QPEI-25000-C6)had good antibacterial effect against Escherichia coli and Staphylococcus aureus at 1.5 mg/mL.Tensile strength and elongation at break indicate that the addition of this metering agent does not affect the mechanical property of hydrocolloid dressing.Degree of comfort,peel strength and tackiness characterize the good adhesion of the hydrocolloid dressing.Cell experiments and hemolysis experiments prove biosafety of hydrocolloid dressings.Compared to the antibacterial hydrocolloid dressings with three different antibacterial agents,it was found that the antibacterial hydrocolloid dressing with 3%QPEI-25000-C6 was more excellent.In summary,this thesis prepared a hydrocolloid dressing with high liquid absorption property,excellent antibacterial property,good blood compatibility and no obvious cytotoxic,which is expected to be used as a novel dressing in clinical.