A split-thickness skin graft (STSG) is used for a large wounds or wounds that cannot be closed by primary and secondary wound closure. Accelerated re-epithelialization rate and minimizing pain and infection are main goals of donor care. Traditionally dressings are inexpensive but adhere to the wound surface and cannot absorb exudates. Thus, we have developed a new biomaterial based on Thai silk for wound dressing application. Silk fibroin and silk sericin were selected to produce wound dressing in this study. The objective of this study is to compare wound dressing containing silk fibroin with bioactive coating layer with standard dressing (medicated paraffin gauze dressing; Bactigras®), with regard to healing time, patients' pain intensity, skin's transepidermal water loss after healing and evidence of infection in the treatment of split-thickness skin graft donor sites. The study design is a randomized, controlled, self paired clinical trial. Patients age 18 to 60 years and undergo STSG at thigh in Department of Surgery, King Chulalongkorn Memorial Hospital will be recruited in the study. The exclusion criteria are donor sites other than thigh area or located at high risk of infection. Patients who are immunocompromised or diabetes mellitus or psychiatric disorders or low serum albumin level (less than 3.0 g/dL) or known allergic to SS or SF or paraffin or chlorhexidine acetate are also excluded. All subjects sign the informed consents after discussion the protocol, benefits and risks. The donor site will be divided into two equal halves, each site will be randomized to receive the tested material or the medicated paraffin gauze dressing. The donor site wounds will be observed daily. The dressings will not be changed, except when they are fully soaked with exudates and easily fell off or any sign of infection. Healing time will be recorded when the dressing separate completely from the donor site, no exudates and no pain when the donor site is exposed to air. The patient's pain level will be evaluated with the visual analogue scale and the donor site wounds will be observed daily for signs of infection. On the day of the wound is recorded for healing time and 1 weeks, 1, 2, 3, 4 and 5 months after that, the skin barrier function (TEWL) of each site will be measured using a Tewameter. Blood sample will be collected from patients pre- and postoperatively (within day 3) for hepatic and renal function analysis.

1. To compare the healing times of the split-thickness skin graft donor site under wound dressing containing silk fibroin woven fabric with bioactive coating layer and medicated paraffin gauze dressing.
2. To compare the patients' pain levels of the split-thickness skin graft donor site under wound dressing containing silk fibroin woven fabric with bioactive coating layer and medicated paraffin gauze dressing.
3. To compare the chance of infections of the split-thickness skin graft donor site under wound dressing containing silk fibroin woven fabric with bioactive coating layer and medicated paraffin gauze dressing.
4. To determine the complications with the use of wound dressing containing silk fibroin woven fabric with bioactive coating layer.

Inclusion Criteria:

• Patients age 18 to 60 years.
• Patients have to undergo a split thickness skin graft.
• The donor sites of split-thickness skin graft locate on the thigh.
• Patients consent to participate in this study.

Exclusion Criteria:

• Donor sites are anywhere else than the thigh area.
• Patients are allergic to silk sericin or silk fibroin or paraffin or chlorhexidine acetate.
• There is a risk of transferring an infection from a nearby infected area to donor site such as acute burn patients.
• Immunocompromised patients such as with acquired immunodeficiency syndrome (AIDS) and renal failure.
• Patients with diabetes mellitus.
• Patients with low serum albumin level (less than 3.0 g/dL)
• Patients have psychiatric disorders or patients with physical disabilities that hinders collaboration.
• Patients who do not comply with the study protocol.
• Pregnancy or lactation