Background/Objective: Antimicrobial resistance (AMR) and therapy-resistant cancer cells represent major clinical challenges, necessitating the development of novel therapeutic strategies. This study explores the use of selenium nanoparticles (SeNPs) and colistin-conjugated selenium nanoparticles (Col-SeNPs) as a dual-function nanotherapeutic against multidrug-resistant Pseudomonas aeruginosa, antifungal-drug-resistant Candida spp., and human breast carcinoma (MCF-7) cells. Methods: SeNPs were synthesized and characterized using UV-Vis spectroscopy, atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FTIR), confirming their nanoscale morphology, purity, and stability. Results: The antimicrobial activity of SeNPs and Col-SeNPs was assessed based on the minimum inhibitory concentration (MIC) and bacterial viability assays. Col-SeNPs exhibited enhanced antibacterial effects against P. aeruginosa, along with significant downregulation of the mexY efflux pump gene, which is associated with colistin resistance. Additionally, Col-SeNPs demonstrated superior antifungal activity against Candida albicans, C. glabrata, and C. krusei compared to SeNPs alone. The anticancer potential of Col-SeNPs was evaluated in MCF-7 cells using the MTT assay, revealing dose-dependent cytotoxicity through apoptosis and oxidative stress pathways. Although MCF-7 is not inherently drug-resistant, this model was used to explore the potential of Col-SeNPs in overcoming resistance mechanisms commonly encountered in cancer therapy. Conclusions: these findings support the promise of Col-SeNPs as a novel approach for addressing both antimicrobial resistance and cancer treatment challenges. Further in vivo studies, including pharmacokinetics and combination therapies, are warranted to advance clinical translation.

تصنف بكتريا Proteus mirabilis كثالث مسبب لالتهاب المجاري البولية المصاحب لتركيب أنابيب القسطرة البولية. تعد الاغشية الحيوية من عوامل الضراوة اللتي تستعملها البكتريا لمقاومة المضادات الحيوية وفي ضل تطور مقاومة البكتريا للمضادات الحيوية, صار لزامًا على العلماء والباحيثن في مجال الاحياء المجهرية أيجاد بدائل ذات كفائة عالية قادرة على اختراق جدار الخلية البكتيرية وبالتالي قتلها.في السنوات الاخيرة, اكتسبت دقائق النانو المصنعة بايولوجيا والصديقة للبيئة أهتمامًا كبيرًا من قبل الباحثين لأمتلاكها خصائص مميزة كصغر حجمها المتناهي واشكالها المختلفة يمَكنهم من استعمالها كمواد مضادة للبكتيريا في مختلف المجلات الطبية والصحية. تهدف هذه الدراسة الى التحري عن قدرة دقائق اوكسيد النحاس النانوية المصنعة بايولوجيا على تثبيط تكوين الغشاء الحيوي المنتج من قبل بكتيريا Proteus mirabilis. أنتجت هذه الدقائق بأستعمال راشح بكتيري يحتوي على الانزيمات المختزلة لملح النحاس واستخدمت عدة تقنيات لتحديد الصفات الفيزيائية المظهرية لدقائق النانو المنتجة حيث استخدمت تقنية XRD لتأكيد التركيب خماسي الشكل لهذه الدقائق , بينما استعملت تقنية TEM لتحديد...

This study aimed to explore whether green synthesized copper nanoparticles (CuNPs) can function as an anti-biofilm agent produced by P. mirabilis. The nanoparticles were synthesized from cells free extract of P. mirabilis. Characterization of biosynthesized copper nanoparticles was carried out to determine the chemical and physical properties of the product using atomic-force microscopy (AFM), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and UV-visible spectroscopy. The hexagonal structure was confirmed by XRD, size range was marked 13-19nm by TEM. FESEM was used to confirm the surface morphology. AFM analysis was used to reveal the roughness and distribution of nanoparticles. UV–visible spectra of the synthesized nanoparticles recorded a maximum peak at 380 nm. Copper nanoparticles showed remarkable biofilm inhibitory effects on wild type strains of multidrug resistant Proteus mirabilis. After incubation for 24 and 48 hours at 37oC with 128 μg/ml sub minimum inhibitory concentration (MIC) of CuO nanoparticles, strong biofilm producer strains showed weak biofilm production. Down regulation changes in LuxS expression using real time PCR technology were detected after treatment with copper nanoparticles of these strains.