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We show that there is a subtle instability of the T' structure for the R2CuO4 (R = rare earth) compounds at the center of the R series with the boundary at R = Eu. Crystals grown in Pt crucibles and PbO flux show weak ferromagnetism (WF) and two temperature-dependent forbidden Raman peaks. Crystals grown in alumina crucibles and CuO flux do not show WF and the forbidden Raman peaks are much weaker. The WF and forbidden Raman peaks in Eu2CuO4 suggests that the instability of the T' structure is associated with O(1) displacement in the CuO2 planes.

Therapeutic intervention to skin wounds requires covering the affected area with wound dressings. Interdisciplinary efforts have focused on the development of smart bandages that can perform multiple functions. In this direction, here, we designed a low cost (U$0.012 per cm 2 ) multifunctional therapeutic wound dressing fabricated by loading curcumin (CC) into poly(ϵ-caprolactone) (PCL) nanofibers using solution blow spinning (SBS). The freestanding PCL/CC bandages were characterized by distinct physicochemical approaches and were successful in performing varied functions, including controlled release of CC, colorimetric indication of the wound conditions, barrier against microorganisms, being biocompatible, and providing a photosensitive platform for antimicrobial photodynamic therapy (aPDT). The chemical nature of PCL and CC and the interactions between these components allowed CC to be released for 192 h (ca. 8 days), which could be correlated with the Korsmeyer-Peppas model, with a burst release suitable to treat the inflammatory phase. Due to the CC keto-enol tautomerism, an optical indication of the healing status could be obtained using PCL/CC, which occurred immediately, ranging between red/orange and yellow shades. The effect against pathogenic microorganisms evaluated by agar disc-diffusion, affected skin wound simulation (ex vivo), and microbial penetration tests demonstrated the ability to block and inhibit microbial permeation in different environments. The biocompatibilities of PCL and PCL/CC were verified by in vitro cytotoxicity study, which demonstrated that cell viabilities average above 94 and 96% for human dermal fibroblasts. In addition, the proposed bandage responded to aPDT applied to an in vivo assay, showing that, when irritated, PCL/CC was able to reduce the bacteria present on the real wound of mice. In summary, our findings demonstrate that using PCL and CC to produce nonwovens by the SBS technique offers potential for the rapid fabrication of biocompatible and multifunctional wound dressings, paving the way for large-scale production and utilization of such dressings in the treatment of skin wounds.