Design of a Portable and Low-Cost Mass Sensitive Quartz Tuning Fork Sensor

The resonance frequency of quartz tuning fork (QTF) depends on the mass adsorbed to its prongs, so it is used to measure minor mass changes and detect target analyte at picogram levels. [...

An alternative electrospinning approach with varying electric field for 2-d-aligned nanofibers

In the electrospinning process, unstructured nanofiber mats are produced by oriented fluid jets with an external electrostatic field. Electrospun fibers have wide applications for the fabrication of composite materials, tissue scaffold, and membranes. However, electrospun fiber production systems have many problems, e. g., the bending instability due to the complicated oscillations of polymer jet. In this research, parallel plate and hollow cylindrical conducting electrodes are implemented through the jet trajectory in order to investigate the possibility of controlled deposition of polymer fibers. Parallel electrodes with proper driving sources can generate the steering field for the nanofiber formation at the collector plate based on analog addressing electronics. It was shown that the modulated electric field applied through the parallel plate electrodes notably increased the deposition of the electrospun polymer fibers in a controlled fashion at the collector, which is coherent to the computer simulations. Furthermore, the finite-length hollow cylinder dampened the bending instabilities of the polymer jet which decreases the characteristic spot size of the deposited electrospun fiber to a smaller diameter.IEEE Nanotechnology Counci

Investigation of Biofilm Formation of ESBL Positive Uropathogenic Escherichia coli Isolates on (Microplate) Surfaces Modified with Plasma Polymerization Technique and Nanomaterials: An Experimental Model

Objective: Extended spectrum beta lactamase (ESBL) positive urinary pathogen Escherichia coli is one of the major agents that lead to catheter-associated urinary tract infection. Prevention of colonization via coating the catheter with biocompatible materials produced by biotechnology is an important step in the prevention of infection. In the presented study, it was aimed to investigate the biofilm formation of ESBL positive urinary pathogen E. coli isolates on microplates which were coated with different bio-compatible nano-materials. Materials and Methods: Biofilm formation of a total of 45 ESBL positive E. coli isolates identified at urine cultures of patients who attended to the medical and surgical outpatient clinics of Ankara TOBB ETU Hospital, on microplates coated with two different monomers [2- hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethacrylate (EGDM)] using plasma polymerization technique was examined. Results: Out of 45 ESBL positive E. coli strains used in the study, 8 were observed to form a slight level of biofilm on uncoated plates whereas on EGDM coated microplates 11, and on HEMA coated microplate only 1 strain formed biofilm. Conclusion: In vitro results showed that using urinary catheters coated with monomer material can reduce catheter associated urinary system infections and morbidity and mortality rates accordingly.Amaç: Kateter ilişkili üriner sistem enfeksiyonlarına neden olan önemli etkenlerden biri GSBL pozitif üropatojen Escherichia coli’dir. Biyoteknoloji ile üretilen biyouyumlu malzemenin katatere kaplanarak kolonizasyonun engellenmesi enfeksiyonun önlenmesinde önemli bir aşamadır. Sunulan araştırmada, GSBL pozitif üropatojen E. coli izolatlarının farklı biyouyumlu nanomalzemelerle kaplanmış mikroplaklardaki biyofilm oluşumuna etkisinin incelemesi amaçlanmıştır. Gereç ve Yöntem: Ankara TOBB ETÜ Hastanesi dâhili ve cerrahi polikliniklere başvuran ayaktan hastaların idrar kültüründen izole toplam 45 GSBL pozitif E. coli izolatının plazma polimerizasyon yöntemiyle iki farklı monomerle [2–hidroksietilmetakrilat (HEMA)] ve Etilen glikol dimetakrilat (EGDM)] kaplanmış mikroplaklarda biyofilm oluşumu araştırılmıştır. Bulgular: Araştırmada kullanılan 45 GSBL pozitif E. coli suşunun 8 tanesi standart yöntemler ile boş plaklarda hafif düzeyde biyofilm oluştururken, EGDM ile kaplanmış mikroplakta 11, HEMA ile kaplanmış mikroplakta ise yalnızca 1 suş biyofilm tabaka oluşturmuştur. Sonuç: Monomer yapılarla kaplanmış üriner kateterlerin kullanılmasının üriner sistemde kateter ilişkili enfeksiyonlarını ve buna bağlı morbidite ve mortalite oranlarını azaltabileceğini gösteren in vitro sonuçlar elde edilmiştir