CITRIC ACID

The management of psoriasis remains challenging due to the limitations of current therapies. This study explores the repurposing of copper diethyldithiocarbamate (CuET)-a metabolite of the anti-alcoholism drug disulfiram-as a novel topical agent for psoriasis. To this end, we developed an advanced delivery platform by fabricating a CuET-loaded nanofiber patch via electrospinning of a polyvinylpyrrolidone/polyethylene glycol/citric acid (PVP/PEG/CA) blend. This rationally designed matrix provided optimal mechanical strength, moisture-activated adhesion, and precise local drug delivery performance, thereby addressing the application challenges associated with xerotic psoriatic skin. In an imiquimod-induced psoriasis mouse model, the nanofiber patch exhibited efficacy comparable to the that of clinical standard clobetasol propionate ointment, significantly alleviating clinical scores and epidermal hyperplasia. Mechanistically, the patch mediated a multimodal therapeutic action: it potently suppressed pathological angiogenesis (reducing CD31 + vessel density by 73.97%) and macrophage infiltration. Crucially, it normalized the dysregulated immune microenvironment by concurrently inhibiting key pro-inflammatory cytokines (IL-17A, IL-22, and IL-1β) and restoring the anti-inflammatory cytokine IL-10 to physiological levels, indicating a reset of the Th17/Treg balance. Comprehensive safety evaluation revealed no systemic toxicity. This work not only validates psoriasis as a new therapeutic indication for CuET but also presents a pioneering combined strategy of drug repurposing and material engineering, offering a safe and effective topical therapy that targets the core immune-vascular pathology of the disease.

Radio nuclear attack scenarios are potential threats that state actors must deal with more than ever in the context of preparedness and response since the Cold War. Radioactive contamination can occur in many scenarios, which means that, in addition to increased skin- and whole-body doses from external radiation exposure, there is also a risk of incorporation and contamination carryover. In many contexts, only theoretical considerations have been made about which substances would be suitable for removing various radioactive compounds. The goal of this work is to systematically investigate the efficacy of various skin decontamination agents in aqueous solutions, e.g., soap, urea peroxide, EDTA, citric acid, and hydrochloric acid. As a model radionuclide we utilized Manganese-56 in two chemical forms: 1. 56MnCl2 and 2. 56MnO2. The contamination was deposited on the surface of ex vivo pig skin during a 15 min contamination protocol. Pre- and post-decontamination measurements were performed by using a lead-shielded gamma spectrometer in a standardized geometry. The counts in 180 s were analyzed after decay and background correction. The decontamination process involved a standardized 30-second spray followed by a single wipe on the pig skin performed by the same decontaminating experimenter. While the tested decontamination agents were approximately equally efficient in removing water-insoluble radioactive contamination (56MnO2), decontamination from water-soluble 56MnCl2 showed a dependency on the decontamination agents. We found that low-concentration aqueous acid solutions (e.g., 3% citric acid) showed a considerably enhanced efficiency compared to a 1% soap solution.

A sensitive analytical protocol was developed to quantify trace levels of three azole fungicides-ketoconazole (KZ), miconazole (MZ), and clotrimazole (CZ)-in cosmetic matrices. This method integrates fiber-in-tube solid-phase microextraction (FIT-SPME) with high-performance liquid chromatography and ultraviolet detection (HPLC-UV). The extraction medium utilized magnesium-aluminum layered double hydroxides (LDHs) intercalated with sodium dodecyl sulfate (SDS), prepared via urea hydrolysis. To fabricate the sorbent, this modified LDH was embedded within a polyvinyl alcohol (PVA) solution-chosen for its green chemistry attributes-and electrospun onto stainless steel substrates. To prevent dissolution in aqueous samples, the coating was thermally cross-linked using citric acid, ensuring robust mechanical stability. The device consisted of these coated fibers housed within a steel capillary, through which samples were circulated for equilibrium adsorption, followed by solvent desorption. A rigorous optimization process was conducted to determine ideal conditions for pH, ionic strength, flow rates, and timing variables. Performance metrics revealed low limits of detection (0.3-0.6 µg L -1 ) and high precision, with inter-day relative standard deviations (RSDs) not exceeding 6.2%. The technique displayed a broad linear dynamic range (up to 750.0 µg L -1 ) and satisfactory determination coefficients (R 2 > 0.9913). Finally, the analysis of real samples, including shampoos, creams, and lotions, yielded relative recoveries ranging from 82% to 115%, confirming the method's reliability for complex formulations.

This study examines how citric acid crosslinking density in Canna edulis ker. starch (CEkS) governs electrosteric stabilization of ZnO nanoparticles under saline stress. Citric acid-modified CEkS polymers spanning degrees of substitution (DS = 0.26-0.67) were synthesized and used to cap ZnO nanoparticles via aqueous co-precipitation. FTIR and XRD confirmed ester formation and ZnO crystallinity, while thermal analysis indicated enhanced thermal resilience of the crosslinked polymer-ZnO system. Colloidal stability was quantified by hydrodynamic diameter (DLS), zeta potential, and UV-Vis turbidity during storage across 0-200 mM NaCl. An intermediate-crosslinked formulation (CA35%) provided the most robust salt tolerance: at 200 mM NaCl, CA35% reached 1271 ± 5 nm after 7 days, whereas the non-modified CEkS control grew to 2633 ± 18 nm. In salt-free dispersions, CA35% remained 301 ± 2 nm at 7 days, while the control reached 2896 ± 6 nm. Higher-crosslinked samples formed stiffer shells that were less tolerant to ionic compression, accelerating aggregation despite more negative surface charge. Overall, the results establish a practical crosslinking-stability design rule for polysaccharide-capped ZnO nanocolloids in ionic media and provide a foundation for subsequent, application-specific validation where safety or regulatory testing is required.

To investigate the enamel/dentin surface loss caused by acidic fluoride-free mouthwashes using dental erosion simulation model. Enamel and dentin bovine slabs (n=8) were subjected to 5 days of treatment (four 1-minute mouthwash treatments/day). Six fluoride-free mouthwashes (MW1-MW6) with varying pH (3.03-5.12) were tested. Three 0.3% citric acid solutions (pH 3.0-5.0) and deionized water served as controls. Surface loss (SL) was measured using non-contact profilometry; enamel hardness was assessed via Knoop microhardness. Data was analyzed using one-way ANOVA. For both substrates, the model was able to differentiate between the controls. Differences between PC5 and NC (0.06± 0.11/-0.13± 0.28) were only directional for enamel. SL ranged considerably between MW1-MW6; however, all were less erosive than PC3 in both substrates. In enamel, MW1 (0.20± 0.12), MW3 (-0.26± 0.29), and MW6 (0.01± 0.12) were not different from NC. MW4 (-0.48± 0.29) was not different from PC4 and PC5, whereas MW5 (-1.19± 0.59) was more erosive than PC5. The SL data for dentin were mostly comparable to enamel. In dentin, MW1 (-0.34± 0.30), MW3 (-0.68± 0.45), and MW6 (-0.79± 0.17) were also not different from NC. Some fluoride-free mouthwashes may cause dental hard tissue erosion, particularly in dentin. Erosive potential appeared to be influenced more by composition than by pH alone. The findings highlight that mouthwash formulations significantly influence enamel and dentin surface loss, with acidity and specific ingredients playing a key role. Clinicians should exercise caution when recommending fluoride-free mouthwashes, especially to patients at risk of erosive tooth wear.

White phosphorus and phosphorus oxide (PO) burns combine thermal and chemical injury, causing deep, progressive necrosis and systemic inflammation. This study evaluated whether carbon dots (CDs) synthesized from citric acid and urea can improve healing of PO-induced skin burns and reduce systemic damage. CDs showed broad antimicrobial activity, most pronounced against Staphylococcus aureus. Application of CD-containing dressings stabilized burn progression, preventing early aggravation and excessive edema, while promoting transient epithelial proliferation during the first week post-burn. Systemically, CDs normalized elevated white blood cell and neutrophil counts, restored lymphocyte balance, and suppressed IL-6 elevation, confirming anti-inflammatory action. They also mitigated erythrocyte loss and anemia development without affecting liver or kidney function. Overall, CD topical application demonstrated antimicrobial, anti-inflammatory, and cytoprotective effects, moderating PO burn progression and supporting balanced wound repair. These findings identify carbon dots as a promising multifunctional platform for the treatment of complex chemical-thermal skin injuries.

This study evaluated the effect of soy-based and milk-based yogurts against enamel erosive-abrasive surface loss. Ninety-eight bovine enamel specimens were randomly allocated to seven experimental groups (n = 14). Over seven days, specimens underwent six daily erosive cycles (0.05 M citric acid, pH 2.3, 2 min), interspersed with remineralizing solution (pH 6.5). Post-acid preventive measures consisted of immersion in milk-based yogurt (pH 4.4), soy-based yogurt (pH 4.7), or tap water for 3 min twice daily. Under erosion-abrasion conditions, specimens underwent simulated toothbrushing using stannous ions-containing fluoride toothpaste. Fluoride-free toothpaste served as abrasion control. Enamel surface loss was measured after 7 days using three-dimensional laser scanning microscopy. Calcium and phosphorus contents were quantified by optical emission spectrometry. Abrasion with a stannous ions-containing fluoride toothpaste combined with soy-based yogurt resulted in significantly lower enamel surface loss (7.9±3.3 μm) compared with the fluoride toothpaste only (12.2 ± 2.7 μm; p<0.05). Under erosion-only conditions, no significant differences were detected among preventive measures. Milk-based yogurt presented significantly higher calcium and phosphorus contents (Ca: 1434.1±190.3 µg/g; P: 1033.8±128.1 µg/g) than soy-based yogurt (Ca: 168.4±15.5 µg/g; P: 623.2±47.7 µg/g). The tested soy yogurt may offer adjunctive protection in patients exposed to erosive and abrasive challenges. The tested soy yogurt significantly enhances anti-erosive efficacy of fluoride-stannous formulations, providing clinicians with an evidence-based dietary intervention to optimize preventive strategies against erosive enamel loss.

Gastrodia elata Blume (G. elata) is a valuable traditional Chinese medicine (TCM) that has been widely used in China. We systematically reviewed tonic and life-extending records in ancient medical literature, as well as the life-prolonging and senescence-delaying effects identified in modern pharmacological research, to provide a theoretical basis for the clinical application and product development of G. elata in tonification and anti-aging. Scientific databases, including CNKI (Chinese literature) and PubMed, were searched to gather relevant literature on the anti-aging effects of G. elata. The targets of the main chemical components of G. elata were predicted and collected through a database, and the intersection of compound targets and disease targets was identified. Protein-protein interaction network analysis, Gene Ontology enrichment, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to explore the potential mechanisms underlying the anti-aging effects of G. elata. The record of G. elata demonstrates a definitive life-extending effect. Modern pharmacological studies have confirmed that it prolongs the lifespan of short-lived animals and slows the aging processes of the brain, skin, bone, and skeletal muscle in animals. Network pharmacology analysis identified 15 common targets shared between candidate target genes of G. elata and anti-aging target genes. TP53, ESR1, EP300, SIRT1, STAT3, CCND1, HDAC2, MDM2, PPARG, TNF, and HSP90AA1 were identified as core genes in the protein-protein interaction (PPI) network analysis. KEGG enrichment analysis indicated that the anti-aging mechanisms of G. elata may be associated with chemical receptor activation, insulin resistance, the citric acid cycle, the PPAR signaling pathway, the glucagon signaling pathway, and the thyroid hormone signaling pathway. This article summarizes previous studies and modern research on the anti-aging effects of G. elata, suggesting that it holds significant potential for clinical applications in anti-aging.

Transdermal drug delivery systems, including microneedles (MNs), offer advantages over oral administration by bypassing gastrointestinal degradation and first-pass metabolism, while also reducing injection-associated pain. Hydrogel-forming microneedles (HFMNs) represent a promising advancement in this field as an alternative strategy. This study aimed to develop an HFMN using poly(vinyl alcohol)/poly(N-vinyl caprolactam) (PVA/PNVCL) with citric acid (CA) as crosslinking agent for transdermal delivery of captopril as a drug model. The HFMNs fabrication was optimised by varying crosslinking time, PNVCL concentration, and CA concentration. Evaluations were conducted on physical properties, mechanical strength, insertion ability, in vitro permeation, and drug content. In vivo skin irritation and antihypertensive efficacy tests were also assessed. A crosslinking time of 45 min, CA concentration of 1.0%, and 10% PNVCL significantly increased the insertion ability, swelling index, permeability and mechanical strength of the HFMNs. Among six formulations, F3 (PVA 15%; PNVCL 10%; CA 1%) demonstrated the most promising performance, achieving in vitro permeation of 66.68 ± 2.78%. In vivo studies showed that oral and transdermal delivery of captopril effectively lowered blood pressure in hypertension-induced rats, with transdermal delivery showing superior efficacy, which warrants further clinical investigation. In addition, in the in vivo skin irritation test, it was observed that HFMNs did not cause irritation. The optimised hydrogel-forming microneedles demonstrated enhanced mechanical strength, permeability, and drug delivery performance. Captopril transdermal delivery using PVA/PNVCL-based HFMNs showed superior antihypertensive efficacy compared to oral administration, with no skin irritation observed, supporting its potential for safe and effective clinical application.

Caprine herpesvirus 1 (CpHV-1) is responsible for significant economic losses in goat farming. The CpHV-1 genital infection in goats has been used as a homologous animal model for the study of human herpes simplex virus type 2 (HSV-2). This study aimed to investigate the in vitro virucidal and antiviral effect of lemon juice (LJ) and its main component, citric acid (CA), against CpHV-1 on Madin-Darby Bovine Kidney (MDBK) cells. Cytotoxicity was assessed using an XTT assay, while viral titers were determined by the Reed-Muench method and viral DNA was quantified via qPCR. Pure LJ (pH 2.3) and its corresponding CA solution demonstrated potent and rapid virucidal activity, reducing the viral titer by over 5.0 log10 TCID 50 /50 µL within 1 min. When applied after viral entry, a non-cytotoxic dilution of LJ (pH 4.32) significantly inhibited viral replication, causing a 2.5 log10 TCID 50 /50 µL reduction in viral titer and a corresponding decrease in viral DNA. The antiviral effects were minimal at a near-neutral pH of 6.67, probably interacting with envelope structures. These results suggest that LJ could be a potential low-cost topical agent or disinfectant for controlling CpHV-1 in goat populations and offer a basis for translational research on human herpesviruses.

The escalating prevalence of antibiotic resistance in Staphylococcus aureus has underscored the urgent necessity for groundbreaking anti-infective therapies that target novel pathways. Metabolic intermediates, such as those in the TCA cycle, have been known to be linked to bacterial virulence. L-Malic acid (L-MA), a natural TCA cycle intermediate, is known for its antimicrobial and antioxidant properties; however, its effect on the virulence of Staphylococcus aureus has yet to be explored. It was found that L-malic acid not only inhibited bacterial growth but also markedly reduced the production of crucial virulence factors, including staphyloxanthin and α-hemolysin. The suppression of pigment synthesis was primarily due to the competitive antagonism of CrtO, a key oxidoreductase responsible for carotenoid biosynthesis in Staphylococcus aureus, coupled with enhanced flux through the TCA cycle that redirected acetyl-CoA pools away from the mevalonate pathway. Moreover, hemolytic activity was decreased by lowering the expression of α-hemolysin. In vivo studies using mouse infection models further demonstrated that L-malic acid effectively mitigated the pathogenicity of Staphylococcus aureus, significantly reducing the formation of skin and liver abscesses. These findings position L-malic acid as a promising agent targeting Staphylococcus aureus infections, highlighting the need for further research into its therapeutic potential.