Nanozyme-incorporated Microneedles for the Treatment of Chronic Wounds.

Acute wounds are converted to chronic wounds due to advanced age and diabetic complications. Nanoenzymes catalyze ROS production to kill bacteria without causing drug resistance, while microneedles (MNs) can break through the skin barrier to deliver drugs effectively. The integration of nanoenzymes into an MNs delivery system can simultaneously improve painless drug delivery and reduce adverse effects. It can also reduce the effective dose of drug sterilization while increasing delivery efficiency and effectively killing wounded bacteria while preventing drug resistance. This paper describes in detail the reasons why nanoenzymes combined with MNs are particularly suitable for the treatment of long-term inflammation and persistent infections in chronic wounds. The antimicrobial properties of different types of metallic nanoenzymes from previous studies were also analyzed, and the mutual reinforcement of MNs made of different materials combined with nanoenzymes was compared. The pooled results showed that the MNs, through material innovation, were able to both penetrate the scab and deliver nanoenzymes and exert additional anti-inflammatory and bactericidal effects. The catalytic effect of some of the nanoenzymes can also accelerate the lysis of the MNs or create a cascade reaction against inflammation and infection. However, the issue of increased toxicity associated with skin penetration and clinical translation remains a challenge. This article reviews the latest published results and corresponding challenges associated with the use of MNs combined with nanoenzymes for the treatment of wounds, providing further information for future research. This article is protected by copyright. All rights reserved.

Metal natural product complex Ru-procyanidins with quadruple enzymatic activity combat infections from drug-resistant bacteria.

Bacterial infection hampers wound repair by impeding the healing process. Concurrently, inflammation at the wound site triggers the production of reactive oxygen species (ROS), causing oxidative stress and damage to proteins and cells. This can lead to chronic wounds, posing severe risks. Therefore, eliminating bacterial infection and reducing ROS levels are crucial for effective wound healing. Nanozymes, possessing enzyme-like catalytic activity, can convert endogenous substances into highly toxic substances, such as ROS, to combat bacteria and biofilms without inducing drug resistance. However, the current nanozyme model with single enzyme activity falls short of meeting the complex requirements of antimicrobial therapy. Thus, developing nanozymes with multiple enzymatic activities is essential. Herein, we engineered a novel metalloenzyme called Ru-procyanidin nanoparticles (Ru-PC NPs) with diverse enzymatic activities to aid wound healing and combat bacterial infections. Under acidic conditions, due to their glutathione (GSH) depletion and peroxidase (POD)-like activity, Ru-PC NPs combined with H2O2 exhibit excellent antibacterial effects. However, in a neutral environment, the Ru-PC NPs, with catalase (CAT) activity, decompose H2O2 to O2, alleviating hypoxia and ensuring a sufficient oxygen supply. Furthermore, Ru-PC NPs possess exceptional antioxidant capacity through their superior superoxide dismutase (SOD) enzyme activity, effectively scavenging excess ROS and reactive nitrogen species (RNS) in a neutral environment. This maintains the balance of the antioxidant system and prevents inflammation. Ru-PC NPs also promote the polarization of macrophages from M1 to M2, facilitating wound healing. More importantly, Ru-PC NPs show good biosafety with negligible toxicity. In vivo wound infection models have confirmed the efficacy of Ru-PC NPs in inhibiting bacterial infection and promoting wound healing. The focus of this work highlights the quadruple enzymatic activity of Ru-PC NPs and its potential to reduce inflammation and promote bacteria-infected wound healing.

Thermally Activated Delayed Fluorescence with Nanosecond Emission Lifetimes and Minor Concentration Quenching: Achieving High-Performance Nondoped and Doped Blue OLEDs.

Simultaneously achieving a high photoluminescence quantum yield (PLQY), ultrashort exciton lifetime, and suppressed concentration quenching in thermally activated delayed fluorescence (TADF) materials is desirable yet challenging. Here, a novel acceptor-donor-acceptor type TADF emitter, namely, 2BO-sQA, wherein two oxygen-bridged triarylboron (BO) acceptors are arranged with cofacial alignment and positioned nearly orthogonal to the rigid dispirofluorene-quinolinoacridine (sQA) donor is reported. This molecular design enables the compound to achieve highly efficient (PLQYs up to 99%) and short-lived (nanosecond-scale) blue TADF with effectively suppressed concentration quenching in films. Consequently, the doped organic light-emitting diodes (OLEDs) base on 2BO-sQA achieve exceptional electroluminescence performance across a broad range of doping concentrations, maintaining maximum external quantum efficiencies (EQEs) at over 30% for doping concentrations ranging from 10 to 70 wt%. Remarkably, the nondoped blue OLED achieves a record-high maximum EQE of 26.6% with a small efficiency roll-off of 14.0% at 1000 candelas per square meter. By using 2BO-sQA as the sensitizer for the multiresonance TADF emitter ν-DABNA, TADF-sensitized fluorescence OLEDs achieve high-efficiency deep-blue emission. These results demonstrate the feasibility of this molecular design in developing TADF emitters with high efficiency, ultrashort exciton lifetime, and minimal concentration quenching.

Comparison of Ba-Hao burn ointment gauze and petrolatum gauze in split graft donor site healing: A randomized, prospective, and self-control study.

Background and Aims: To assess patient comfort, wound healing, and scarring at the 6-month follow-up of split-skin graft donor sites treated with Ba-Hao burn ointment (BHBO) gauze, a compound preparation of traditional Chinese medicine since 1970s, compared with petrolatum gauze. Methods: Thirty patients admitted to the Department of Burns of the First Affiliated Hospital of Anhui Medical University between September 2021 and September 2022 participated in this randomized, prospective, self-control clinical study. After harvesting the split skin, donor sites were divided into two parts along the midline. BHBO gauze was applied to half of the donor wounds, and petrolatum gauze was applied to the other half. The wound healing time, pain scores on the postoperative Days 3, 6, and 9, and Vancouver Scar Scale (VSS) score at the 6-month follow-up were assessed. Results: The wound healing time was significantly shorter in the BHBO group than in the control group (10.07 ± 1.48 days vs. 11.50 ± 1.74 days, p < 0.001). On postoperative Days 3 and 6, the pain scores quantified by visual analog scores were significantly lower in the BHBO group than in the control group (5.33 ± 1.54 and 4.17 ± 1.51, respectively vs. 7.57 ± 1.41 and 5.20 ± 1.47, respectively). The difference in the visual analog scale score on postoperative Day 9 between the groups was not significant (p > 0.05). Microbiological assessment revealed the absence of bacterial contamination in both groups. At the 6-month follow up, the VSS score was significantly lower in the BHBO group (6.67 ± 1.92) than in the control group (9.57 ± 1.55). Conclusion: BHBO resulted in faster donor-site healing, reduced postoperative pain, and improved scar quality at the 6-month follow-up than petrolatum gauze alone.

Efficacy of hydrosurgical eschar excision following MEEK microskin grafting in patients with massive burns: A retrospective study of a single center.

INTRODUCTION: One of the most common traumatic injuries, burn injuries lead to at least 180,000 deaths each year worldwide. Massive burns result in severe tissue loss and increase the rate of infection. Eschar excision with skin grafting is the gold standard of treatments for massive burns. Retaining dermis tissue is the key to ensuring the survival of skin grafts and rapidly closing exposed tissues. Traditional eschar excision with Humby or Weck knife controls the depth of excision until the dermis, but ensuring the accuracy of excision is challenging. Hydrosurgery minimizes damage to uninjured tissues during the removal of necrotic tissues. A foot pedal is used to adjust debridement depth for precise debridement. To figure out the clinical advantages and risks of using hydrosurgery in treating massive burns, this study has been conducted. METHOD: Forty-two patients with massive burns and total body surface area (TBSA) of > 30% were treated at the First Affiliated Hospital of Anhui Medical University from May 2020 to January 2023. They underwent hydrosurgical eschar excision with MEEK microskin graft (n = 23) or tangential excision with MEEK microskin graft (n = 19). RESULT: No statistically significant differences (p > 0.05) in the following demographics were found between the two groups: age, weight, TBSA, deep-partial-thickness burn, gender, inhalation injury, shock, excision area, and MEEK ratio. By contrast, statistically significant differences in per unit area of operation time, per unit area of operation spending, hospitalization cost, hospitalization duration, wound-healing time, skin graft survival, and scar quality were found between hydrosurgical excision group with MEEK microskin graft and conventional excision group with MEEK microskin graft. CONCLUSION: The hydrosurgical excision system showed better clinical effects for patients with massive burns.

Patients with hypertrophic scars following severe burn injury express different long noncoding RNAs.

OBJECTIVE: Research indicates that long noncoding RNAs (lncRNAs) contribute significantly to fibrotic diseases. Although lncRNAs may play a role in hypertrophic scars after burns, its mechanisms remain poorly understood. METHODS: Using chip technology, we compared the lncRNA expression profiles of burn patients and healthy controls (HCs). Microarray results were examined by quantitative reverse-transcription polymerase chain reaction (RT-PCR) to verify their reliability. The biological functions of differentially expressed mRNAs and the relationships between genes and signaling pathways were investigated by Gene Ontology (GO) and pathway analyses, respectively. RESULTS: In contrast with HCs, it was found that 2738 lncRNAs (1628 upregulated) and 2166 mRNAs (1395 upregulated) were differentially expressed in hypertrophic scars after burn. Results from RT-PCR were consistent with those from microarray. GO and pathway analyses revealed that the differentially expressed mRNAs are mainly associated with processes related to cytokine secretion in the immune system, notch signaling, and MAPK signaling. CONCLUSION: The lncRNA expression profiles of hypertrophic scars after burn changed significantly compared with HCs. It was believed that the transcripts could be used as potential targets for inhibiting abnormal scar formation in burn patients.

Multifunctional Cu2 Se/F127 Hydrogel with SOD-Like Enzyme Activity for Efficient Wound Healing.

Free radicals are secreted following skin damage and cause oxidative stress and inflammatory reactions that increase the difficulty of wound healing. In this study, copper-based nanozyme Cu2 Se nanosheets (NSs) are synthesized by an anion-exchange strategy and apply to wounds with F127 hydrogels to investigate the healing effect of this nanozyme composite hydrogels on wounds. Cu2 Se NSs have a large number of catalytically active centers, are simple to synthesize, require few reaction conditions and have a short synthesis cycle. In vitro experiments have shown that Cu2 Se NSs possess superoxide dismutase (SOD)-like activity and nitrogen radical scavenging activity and promote angiogenesis and fibroblast migration. The doping of Cu2 Se NSs into the F127 hydrogel does not have a significantly affect on the properties of the hydrogel. This hybridized hydrogel not only adapts to the irregular and complex morphology of acute wounds but also prolongs the duration of nanozyme action on the wound, thus promoting wound healing. Transcriptomic analysis further reveals the potential therapeutic mechanism of the Cu2 Se/F127 hydrogel in promoting acute wound healing. Animal experiments have shown that the Cu2 Se/F127 hydrogel has good biosafety. The Cu2 Se/F127 hydrogel provides an innovative idea for the development of hydrogel dressings for the treatment of acute wounds.

Application of nanotechnology in the treatment of glomerulonephritis: current status and future perspectives.

Glomerulonephritis (GN) is the most common cause of end-stage renal failure worldwide; in most cases, it cannot be cured and can only delay the progression of the disease. At present, the main treatment methods include symptomatic therapy, immunosuppressive therapy, and renal replacement therapy. However, effective treatment of GN is hindered by issues such as steroid resistance, serious side effects, low bioavailability, and lack of precise targeting. With the widespread application of nanoparticles in medical treatment, novel methods have emerged for the treatment of kidney diseases. Targeted transportation of drugs, nucleic acids, and other substances to kidney tissues and even kidney cells through nanodrug delivery systems can reduce the systemic effects and adverse reactions of drugs and improve treatment effectiveness. The high specificity of nanoparticles enables them to bind to ion channels and block or enhance channel gating, thus improving inflammation. This review briefly introduces the characteristics of GN, describes the treatment status of GN, systematically summarizes the research achievements of nanoparticles in the treatment of primary GN, diabetic nephropathy and lupus nephritis, analyzes recent therapeutic developments, and outlines promising research directions, such as gas signaling molecule nanodrug delivery systems and ultrasmall nanoparticles. The current application of nanoparticles in GN is summarized to provide a reference for better treatment of GN in the future.

The progression of inorganic nanoparticles and natural products for inflammatory bowel disease.

There is a growing body of evidence indicating a close association between inflammatory bowel disease (IBD) and disrupted intestinal homeostasis. Excessive production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), along with an increase in M1 proinflammatory macrophage infiltration during the activation of intestinal inflammation, plays a pivotal role in disrupting intestinal homeostasis in IBD. The overabundance of ROS/RNS can cause intestinal tissue damage and the disruption of crucial gut proteins, which ultimately compromises the integrity of the intestinal barrier. The proliferation of M1 macrophages contributes to an exaggerated immune response, further compromising the intestinal immune barrier. Currently, intestinal nanomaterials have gained widespread attention in the context of IBD due to their notable characteristics, including the ability to specifically target regions of interest, clear excess ROS/RNS, and mimic biological enzymes. In this review, we initially elucidated the gut microenvironment in IBD. Subsequently, we delineate therapeutic strategies involving two distinct types of nanomedicine, namely inorganic nanoparticles and natural product nanomaterials. Finally, we present a comprehensive overview of the promising prospects associated with the application of nanomedicine in future clinical settings for the treatment of IBD (graphic abstract). Different classes of nanomedicine are used to treat IBD. This review primarily elucidates the current etiology of inflammatory bowel disease and explores two prominent nanomaterial-based therapeutic approaches. First, it aims to eliminate excessive reactive oxygen species and reactive nitrogen species. Second, they focus on modulating the polarization of inflammatory macrophages and reducing the proportion of pro-inflammatory macrophages. Additionally, this article delves into the treatment of inflammatory bowel disease using inorganic metal nanomaterials and natural product nanomaterials.

Multicenter effect analysis of one-step acellular dermis combined with autologous ultra-thin split thickness skin composite transplantation in treating burn and traumatic wounds.

To evaluate the efficacy of one-step acellular dermis combined with autologous split thickness skin grafting in the treatment of burn or trauma wounds by a multicenter controlled study. In patients with extensive burns, it is even difficult to repair the wounds due to the shortage of autologous skin. The traditional skin grafting method has the disadvantages of large damage to the donor site, insufficient skin source and unsatisfactory appearance, wear resistance and elasticity of the wound tissue after skin grafting. One-step acellular dermis combined with autologous ultra-thin split thickness skin graft can achieve better healing effect in the treatment of burn and trauma wounds. A total of 1208 patients who underwent single-layer skin grafting and one-step composite skin grafting in the First Affiliated Hospital of Wannan Medical College, Wuhan Third People's Hospital and Lu 'an People's Hospital from 2019 to 2022 were retrospectively analysed. The total hospitalization cost, total operation cost, hospitalization days after surgery, wound healing rate after 1 week of skin grafting and scar follow-up at 6 months after discharge were compared and studied. The total cost of hospitalization and operation in the composite skin grafting group was significantly higher than those in the single-layer autologous skin grafting group. The wound healing rate after 1 week of skin grafting and the VSS score of scar in the follow-up of 6 months after discharge were better than those in the single-layer skin grafting group. One-step acellular dermis combined with autologous ultra-thin split thickness skin graft has high wound healing rate, less scar, smooth appearance and good elasticity in repairing burn and trauma wounds, which can provide an ideal repair method for wounds.

Copper Nanodots-Based Hybrid Hydrogels with Multiple Enzyme Activities for Acute and Infected Wound Repair.

Effectively controlling bacterial infection, reducing the inflammation and promoting vascular regeneration are all essential strategies for wound repair. Nanozyme technology has potential applications in the treatment of infections because its non-antibiotic dependent, topical and noninvasive nature. In wound management, copper-based nanozymes have emerged as viable alternatives to antibiotics. In this study, an ultrasmall cupric enzyme with high enzymatic activity is synthesized and added to a nontoxic, self-healing, injectable cationic guar gum (CG) hydrogel network. The nanozyme exhibits remarkable antioxidant properties under neutral conditions, effectively scavenging reactive nitrogen and oxygen species (RNOS). Under acidic conditions, Cu NDs have peroxide (POD) enzyme-like activity, which allows them to eliminate hydrogen peroxides and produce free radicals locally. Antibacterial experiments show that they can kill bacteria and remove biofilms. It reveals that low concentrations of Cu ND/CG decrease the expression of the inflammatory factors in cells and tissues, effectively controlling inflammatory responses. Cu ND/CG hydrogels also inhibit HIF-1α and promote VEGF expression in the wound with the ability to promote vascular regeneration. In vivo safety assessments reveal a favorable biosafety profile. Cu ND/CG hydrogels offer a promising solution for treating acute and infected wounds, highlighting the potential of innovative nanomaterials in wound healing.

Safety and efficacy of waterjet debridement vs. conventional debridement in the treatment of extremely severe burns: A retrospective analysis.

INTRODUCTION: Patients with extremely severe burns often require rapid wound closure with a tangential excision or escharectomy combined with a skin graft to reduce life-threatening complications such as infection. Traditional tangential excision surgery using the Watson or Humby knife does not allow accurate excision of necrotic tissue and often removes too much active tissue, which is detrimental to the rapid healing of the wound. Importantly, the Versajet hydrosurgical system, with its smaller handle, allows for more precise excision of necrotic burn tissue and preserves more active dermal tissue, positively affecting wound healing and scarring. This study compared the safety and efficacy of hydrosurgical combined with autologous skin grafting to conventional excision combined with autologous skin grafting in patients with extremely severe burn. METHODS: Information of sixty burn patients with total body surface area (TBSA) > 50 % treated at the first affiliated hospital of Anhui Medical University from January 2019 to August 2022 were analyzed. The patients were divided into a conventional debridement group (n = 37) and a hydrosurgical debridement group (n = 23) according to the approach used. The hydrosurgical debridement group and the conventional debridement group were compared from the difference between the duration of the first debridement surgery, wound healing time, the changes of red blood cells and hemoglobin concentration postoperative, total blood transfusion, hospitalization cost, skin grafting frequency, procalcitonin, wound bacterial culture, albumin and prealbumin. RESULTS: Information on age, gender, weight, inhalation injury, hypovolemic shock, preoperative procalcitonin, preoperative albumin, preoperative prealbumin, the operation frequency (n ≥ 3), preoperative trauma culture and postoperative trauma culture were compared between both groups (P > 0.05). Operative time and wound healing time were significantly shorter in patients with hydrosurgical debridement combined with autologous skin grafting than those in the control group (P < 0.05), while hospitalization costs were not significantly different between the two groups (P > 0.05). The changes of red blood cells and hemoglobin concentration during the postoperative period in the hydrosurgical debridement group were less significantly than those in the conventional debridement group (P < 0.05). The total amount of red blood cells transfused during hospitalization was significantly lower in the hydrosurgical debridement group than that in the conventional debridement group (P < 0.05), but the total amount of fresh frozen plasma transfused during hospitalization was not statistically significant between the two groups (P > 0.05). Albumin on the third day after surgery and prealbumin on the first, third and fifth day after surgery improved more significantly than those in the control group(P < 0.05), however, there were no significant differences between the two groups in albumin on the first and fifth postoperative days (P > 0.05). The PCT level in the conventional debridement group was significantly higher than that in the hydrosurgical debridement group on the first, third and fifth days after surgery(P < 0.05). CONCLUSION: The hydrosurgical debridement group presented with shorter operative time, less blood loss during surgery, faster postoperative nutritional recovery, less postoperative inflammatory response and faster wounds healing, and did not increase the hospitalization cost, postoperative bacterial culture of the wounds and the number of skin grafting surgeries. In patients with extremely severe burn, hydrosurgical debridement combined with autologous skin grafting group is safer and more effective than those in the conventional debridement combined with autologous skin grafting group.

Rotational isomerization: spontaneous structural transformation of a thermally activated delayed fluorescence binuclear copper(I) complex.

A novel binuclear Cu(I) halide complex, Cu2I2(DPPCz)2, which emits efficient thermally activated delayed fluorescence (TADF), is reported. The crystal of this complex spontaneously undergoes ligand rotation and coordination-configuration transformation, converting to its isomer without any external stimulation.

Chitosan-based double network hydrogel loading herbal small molecule for accelerating wound healing.

Skin injuries are one of the most common clinical traumas worldwide, and wound dressings are considered to be one of key factors in wound healing. Natural polymer-based hydrogels have been developed as ideal materials for a new generation of dressings due to their excellent biocompatibility and wetting ability. However, the inadequate mechanical performances and lack of efficacy in promoting wound healing have limited the application of natural polymer-based hydrogels as wound dressings. In this work, a double network hydrogel based on natural chitosan molecules was constructed to enhance the mechanical properties, and emodin, a herbal natural product, was loaded into the hydrogel to improve the healing effect of the dressing. The structure of the chitosan-emodin network formed by Schiff base reaction and microcrystalline network of biocompatible polyvinyl alcohol endowed hydrogels with excellent mechanical properties and ensured its integrity as wound dressings. Moreover, the hydrogel showed excellent wound healing properties due to the loading of emodin. The hydrogel dressing could promote cell proliferation, cell migration, and secretion of growth factors. The animal experimental results also demonstrated that the hydrogel dressing facilitated the regeneration of blood vessels and collagen and accelerated wound healing.

Rational Design of Highly Efficient Orange-Red/Red Thermally Activated Delayed Fluorescence Emitters with Submicrosecond Emission Lifetimes.

The development of orange-red/red thermally activated delayed fluorescence (TADF) materials with both high emission efficiencies and short lifetimes is highly desirable for electroluminescence (EL) applications, but remains a formidable challenge owing to the strict molecular design principles. Herein, two new orange-red/red TADF emitters, namely AC-PCNCF3 and TAC-PCNCF3, composed of pyridine-3,5-dicarbonitrile-derived electron-acceptor (PCNCF3) and acridine electron-donors (AC/TAC) are developed. These emitters in doped films exhibit excellent photophysical properties, including high photoluminescence quantum yields of up to 0.91, tiny singlet-triplet energy gaps of 0.01 eV, and ultrashort TADF lifetimes of less than 1 µs. The TADF-organic light-emitting diodes employing the AC-PCNCF3 as emitter achieve orange-red and red EL with high external quantum efficiencies of up to 25.0% and nearly 20% at doping concentrations of 5 and 40 wt%, respectively, both accompanied by well-suppressed efficiency roll-offs. This work provides an efficient molecular design strategy for developing high-performance red TADF materials.

Realizing High-Efficiency Orange-Red Thermally Activated Delayed Fluorescence Materials through the Construction of Intramolecular Noncovalent Interactions.

The development of highly efficient orange and red thermally activated delayed fluorescence (TADF) materials for constructing full-color and white organic light-emitting diodes (OLEDs) remains insufficient because of the formidable challenges in molecular design, such as the severe radiationless decay and the intrinsic trade-off between the efficiencies of radiative decay and reverse intersystem crossing (RISC). Herein, we design two high-efficiency orange and orange-red TADF molecules by constructing intermolecular noncovalent interactions. This strategy could not only ensure high emission efficiency via suppression of the nonradiative relaxation and enhancement of the radiative transition but also create intermediate triplet excited states to ensure the RISC process. Both emitters exhibit typical TADF characteristics, with a fast radiative rate and a low nonradiative rate. Photoluminescence quantum yields (PLQYs) of the orange (TPA-PT) and orange-red (DMAC-PT) materials reach up to 94 and 87%, respectively. Benefiting from the excellent photophysical properties and stability, OLEDs based on these TADF emitters realize orange to orange-red electroluminescence with high external quantum efficiencies reaching 26.2%. The current study demonstrates that the introduction of intermolecular noncovalent interactions is a feasible strategy for designing highly efficient orange to red TADF materials.

Tröger's Base-Derived Thermally Activated Delayed Fluorescence Dopant for Efficient Deep-Blue Organic Light-Emitting Diodes.

The development of efficient deep-blue emitters with thermally activated delayed fluorescence (TADF) properties is a highly significant but challenging task in the field of organic light-emitting diode (OLED) applications. Herein, we report the design and synthesis of two new 4,10-dimethyl-6H,12H-5,11-methanodibenzo[b,f][1,5]diazocine (TB)-derived TADF emitters, TB-BP-DMAC and TB-DMAC, which feature distinct benzophenone (BP)-derived acceptors but share the same dimethylacridin (DMAC) donors. Our comparative study reveals that the amide acceptor in TB-DMAC exhibits a significantly weaker electron-withdrawing ability in comparison to that of the typical benzophenone acceptor employed in TB-BP-DMAC. This disparity not only causes a noticeable blue shift in the emission from green to deep blue but also enhances the emission efficiency and the reverse intersystem crossing (RISC) process. As a result, TB-DMAC emits efficient deep-blue delay fluorescence with a photoluminescence quantum yield (PLQY) of 50.4% and a short lifetime of 2.28 µs in doped film. The doped and non-doped OLEDs based on TB-DMAC display efficient deep-blue electroluminescence with spectral peaks at 449 and 453 nm and maximum external quantum efficiencies (EQEs) of 6.1% and 5.7%, respectively. These findings indicate that substituted amide acceptors are a viable option for the design of high-performance deep-blue TADF materials.

Diagnostic value of procalcitonin and red blood cell distribution width at admission on the prognosis of patients with severe burns: A retrospective analysis.

The plasma procalcitonin (PCT) concentration and red blood cell distribution (RDW) value after severe burns can be used as prognostic indicators, but at present, it is difficult to give consideration to sensitivity and specificity in diagnosing the prognosis of severe burns with a single indicator. This study analysed the diagnostic value of plasma PCT concentration and RDW value at admission on the prognosis of severe burn patients to improve its sensitivity and specificity. A total of 205 patients with severe burns who were treated in the First Affiliated Hospital of Anhui Medical University from November 2017 to November 2022 were retrospectively analysed. The optimal cut-off values of plasma PCT concentration and RDW were analysed and counted through the subject curve (ROC curve). According to the cut-off value, patients were divided into high PCT group and low PCT group, high RDW group and low RDW group. The independent risk factors of severe burns were analysed by single-factor and multiple-factor COX regression. Kaplan-Meier survival was used to analyse the mortality of high PCT group and low PCT group, high RDW group and low RDW group. The area under the curve of plasma PCT concentration and RDW value at admission was 0.761 (95% CI, 0.662-0.860, P < .001), 0.687 (95% CI, 0.554-0.820, P = .003) respectively, and the optimal cut-off values of serum PCT concentration and RDW were 2.775 ng/mL and 14.55% respectively. Cox regression analysis found that age, TBSA, and RDW were independent risk factors for mortality within 90 days after severe burns. Kaplan-Meier survival analysis showed that there was a significant difference in the 90-day mortality rate of severe burns between the PCT ≥ 2.775 ng/mL group and the PCT < 2.775 ng/mL group (log-rank: 24.162; P < .001), with the mortality rate of 36.84% versus 5.49%, respectively. The 90-day mortality rate of severe burns was significantly different between the RDW ≥ 14.55% group and the RDW < 14.55% group (log-rank: 14.404; P < .001), with the mortality rate of 44% versus 12.2% respectively. The plasma PCT concentration and RDW value at admission are both of diagnostic value for the 90-day mortality of severe burns, but the plasma PCT concentration has higher sensitivity and the RDW value has higher specificity. Age, TBSA, and RDW were independent risk factors for severe burns, and then plasma PCT concentration was not independent risk factors.

High-Contrast Visualization Chemiluminescence Based on AIE-Active and Base-Sensitive Emitters.

Peroxyoxalate chemiluminescence (PO-CL) is one of the most popular cold light sources, yet the drawback of aggregation-caused quenching limits their use. Here, we report a new kind of efficient bifunctional emitter derived from salicylic acid, which not only exhibits typical aggregation-induced emission (AIE) character but also has the ability to catalyze the CL process under basic conditions based on base sensitivity. By taking advantage of these unique features, we successfully confine the CL process on the surface of solid bases and provide a high-contrast visualization of CL emission. This method allows most of the common basic salts like sodium carbonate to be invisible encryption information ink and PO-CL solution to be a decryption tool to visualize the hidden information. The current study opens up an appealing way for the development of multifunction CL emitters for information encryption and decryption applications.

Efficient Spin-Flip between Charge-Transfer States for High-Performance Electroluminescence, without an Intermediate Locally Excited State.

Thermally activated delayed fluorescence (TADF) materials with both high photoluminescence quantum yield (PLQY) and fast reverse intersystem crossing (RISC) are strongly desired to realize efficient and stable organic light-emitting diodes (OLEDs). Control of excited-state dynamics via molecular design plays a central role in optimizing the PLQY and RISC rate of TADF materials but remains challenging. Here, 3 TADF emitters possessing similar molecular structures, similar high PLQYs (89.5% to 96.3%), and approximate energy levels of the lowest excited singlet states (S1), but significantly different spin-flipping RISC rates (0.03 × 106 s-1 vs. 2.26 × 106 s-1) and exciton lifetime (297.1 to 332.8 µs vs. 6.0 µs) were systematically synthesized to deeply investigate the feasibility of spin-flip between charge-transfer excited states (3CT-1CT) transition. Experimental and theoretical studies reveal that the small singlet-triplet energy gap together with low RISC reorganization energy between the 3CT and 1CT states could provide an efficient RISC through fast spin-flip 3CT-1CT transition, without the participation of an intermediate locally excited state, which has previously been recognized as being necessary for realizing fast RISC. Finally, the OLED based on the champion TADF emitter achieves a maximum external quantum efficiency of 27.1%, a tiny efficiency roll-off of 4.1% at 1,000 cd/m2, and a high luminance of 28,150 cd/m2, which are markedly superior to those of the OLEDs employing the other 2 TADF emitters.