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Artificial motors (robots) that are inspired by natural motors have captivated much attention with their attractive performances and special features. These miniaturized nano/micromotors have succeeded many important tasks in different fields including (bio)sensing, cargo transport, cell isolation and trapping, nanosurgery, gene therapy, and drug delivery. Herein, paclitaxel (PTX)-conjugated robots consisted of poly(3-aminophenylboronic acid) outer layer, a platinum (Pt)-nickel (Ni) segment, and a Pt catalytic inner layer were constructed to demonstrate their effective use for smart drug delivery. These self-functionalized motors had effective and smooth autonomous movement at velocities of 44 ± 9 μm/s and 34 ± 4 μm/s after 6 and 12 h of drug incubation steps. Fabrication of these motors was relied on electrochemical protocols, and the drug loading process was carried out by the interaction of the antitumor agent with the outer polymeric layer of the robots. Targeted delivery of the drug was achieved by the controlled driven of the robots toward human breast cancer cell line via induced Near-Infrared irradiation (NIR). pH dependency of the system was also demonstrated at acidic pH values. It was shown that the near-infrared irradiation increased the efficiency of the drug release through the polymeric robots. Polymeric robots showed promising viability results by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tetrazolium reduction (MTT) assays in order to signify potential and practical applications.

Magnetically guided ultrasound-powered nanowire motors, functionalized with bioreceptors and a drug-loaded polymeric segment, are described for “capture and transport” and drug-delivery processes. These high-performance fuel-free motors display advanced capabilities and functionalities, including magnetic guidance, coordinated aligned movement, cargo towing, capture and isolation of biological targets, drug delivery, and operation in real-life biological and environmental media. The template-prepared three-segment Au–Ni–Au nanowire motors are propelled acoustically by mechanical waves produced by a piezoelectric transducer. An embedded nickel segment facilitates a magnetically guided motion as well as transport of large “cargo” along predetermined trajectories. Substantial improvement in the speed and power is realized by the controlled concavity formation at the end of the motor nanowire using a sphere lithography protocol. Functionalization of the Au segments with lectin and antiprotein A antibody bioreceptors allows capture and transport of E. coliand S. aureusbacteria, respectively. Potential therapeutic applications are illustrated in connection to the addition of a pH-sensitive drug-loaded polymeric (PPy-PSS) segment. The attractive capabilities of these fuel-free acoustically driven functionalized Au–Ni–Au nanowires, along with the simple preparation procedure and minimal adverse effects of ultrasonic waves, make them highly attractive for diverse in vivobiomedical applications.

Bio‐logisch: Ein autonomes, integriertes System auf Basis einer enzymatischen Biotreibstoffzelle zur Detektion und Behandlung abnormer physiologischer Zustände koppelt logische Detektion durch einen Biosensor mit Wirkstoff‐Freisetzung. Das Resultat ist eine Logik‐aktivierte therapeutische Intervention als Reaktion auf einen simulierten abnormen physiologischen Zustand, die ohne externe Stromquelle, Steuerelektronik oder mikroelektromechanische Aktuatoren auskommt.

Bio‐logic‐al: An autonomous, integrated “sense‐act‐treat” system that is based on an enzymatic biofuel cell has been developed. The system couples a biocomputing logic‐detection method with a drug‐release system to provide a logic‐activated therapeutic intervention in response to a simulated abnormal physiological state, without the need for an external power source, control electronics, or microelectromechanical actuators.

The use of nanomaterials in many life sciences for biological, pharmaceutical, clinical and environmental applications has attracted great attention. Among these nanomaterials, carbon nanotubes (CNTs) are widely used due to their good chemical, mechanical, electrical, optical and thermal properties. CNTs are also superior to other carbon-based materials mainly in special structure features. These advantages make CNTs very popular in electrochemistry for many applications including nanoelectronic devices, composites, chemical sensors and biosensors. Electrochemistry allows rapid, low cost and easy preparation of new electrodes for different purposes. The detection of DNA using electrochemical techniques is in increasing demand for obtaining high sensitivity, selectivity and stability. In this sense, the combination of electrochemistry and CNTs provides great opportunities by promoting electron transfer reactions, increasing surface area, enhancing signals and maintaining biocompatibility. This work summarizes the methodologies used in electrochemical DNA detection based on CNTs. Electrochemical DNA detection using CNT modified electrodes, CNT-polymer modified electrodes, CNT-nanoparticle modified electrodes and their applications are discussed in details. The combination of these technologies for electrochemical DNA detection is also summarized in the work.

The electrochemical investigation of the interaction between the anticancer drug mitomycin C (MC) and DNA was described using a single‐walled carbon nanotube (SWCNT)/poly(vinylferrocenium) (PVF+) modified pencil graphite electrode (PGE). The electrochemical oxidation signals of guanine were monitored before and after the interaction between MC and DNA by using differential pulse voltammetry. The effects of DNA and MC concentration and MC interaction time were examined based on the electrode response. Cyclic voltammetry and electrochemical impedance spectroscopy were used for the characterization of SWCNT/PVF+modified and PVF+modified PGEs. The detection limit corresponded to 625 ng/mL for MC using calf thymus double‐stranded DNA immobilized SWCNT/PVF+modified PGE.

Electrochemical biosensors have a key importance in many areas including clinical, biological, pharmaceutical, forensic, environmental and agricultural applications. They have the advantages of rapid, easy and low cost preparation allowing the localization of biocompound on electrodes of any size with independence of sample turbidity, high sensitivity and high selectivity. Electrochemical devices have attracted considerable interest in the development of DNA hybridization biosensors. They rely on the conversion of hybridization event into a direct electrochemical signal. Many efforts have been carried out in the detection of DNA hybridization for improving the stability, reproducibility and sensitivity. This review summarizes the advanced electrochemical methodologies involved in nucleic acid hybridization performed by using polymer technology, nanoparticles (NPs), magnetic particles, and carbon nanotubes (CNTs). The preparation of polymer modified electrodes especially including conducting polymers and their applications for DNA hybridization are given with the advantages of electrocatalysis, good electroactivity, high sensitivity and providing suitable matrix for DNA immobilization. The role of various nanomaterials in biosensors with the advantages of high surface area, fast heterogeneous electron transfer, excellent biocompatibility and enhanced signal with a good selectivity are presented. The combination of these techniques is also discussed in details.

The polymer, poly(vinylferrocenium) (PVF+) modified electrode was developed as the first time herein for the improved electrochemical sensing of DNA based on the oxidation signals of polymer and guanine. The morphologies of polymer film and DNA immobilized polymer film were examined using scanning electron microscope (SEM). The electrochemical behavior of polymer modified electrode was investigated by using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) in the absence/presence of DNA. Experimental parameters, such as the polymeric film thickness, the DNA immobilization time, the concentration of buffer solution, pH and DNA concentration were examined in order to obtain more sensitive and selective electrochemical signals. After optimization studies, DNA hybridization was also investigated.

Constant current chronopotentiometric peak H at mercury electrodes was recently shown as a sensitive tool for global and local changes in protein conformation [1]. Large differences between the heights of peak H of native (hBSAnat) and denatured BSA (hBSAden) were observed. The ratio hBSAden/hBSAnatincreased with more negative stripping current suggesting that the rate of potential change is important for discrimination between native and denatured BSA. Voltammetric peaks of BSA were less well developed and BSAden/BSAnatwas much smaller. It was not possible to discriminate BSAdenand BSAnatusing carbon electrodes.

Abstract:  The effect of haematocrit and β-carotene levels on the serum total bilirubin measurement in two analytical methods was studied as an example of the impact of practical analytical quality in medical decision making. The precision characteristics of the two methods were very similar. Based upon the significant difference in the correlation coefficient in a method comparison study before and after 20% trimming of the data, an interference effect study was performed. Haemoglobin (expressed as haematocrit) and β-carotene were the substances studied to explain the observed differences. The bilirubin test results from the Wako bilirubinometer were easily affected (n=19;X(S): 13.83±2.43;t=–6.17;P=0.000) and more elevated than in the Vitros dry chemistry systems (n=18;X(S): 12.72±2.21;t=–2.48;P=0.017), due to the presence of β-carotene (>200 μg/dl).

In order to evaluate the effect of alpha interferon on erythrocyte membrane Na+, K+ ATPase (EC 3.6.1.37) activity, 10 patients with chronic hepatitis B virus (HBV) infection and 8 patients with chronic hepatitis C virus (HCV) infection were investigated. Erythrocyte membrane Na+, K+ ATPase activity was determined in controls and in patients with HBV and HCV infection. Na+, K+ ATPase activity was significantly less in untreated patients with (HBV) infection (n=20; 0,134±0,073 μmol of phosphate produced per milligram of protein per hour) and (HCV) infection (n=11; 0,144±0,049) when compared to the controls (n=10; 0,219±0,055). Among these subjects patients were treated with interferon and following treatment, significant elevation of Na+, K ATPase activity was seen in patients with HCV (n=8; 0,183±0,044; P=0,049) and HBV (n=10, 0,213±0,095, P=0,0069) infections when compared with the pre‐treatment values (n=8; 0,152±0,050) and (n=10, 0,131±0,083), respectively. Normalization of serum alanin amino transferase levels (ALT) at treatment cessation was seen in 8 of 10 (%80) HBV infected patients of whom 2 of 8 (%25) had sustained ALT responses within three months after the end of treatment. In HCV infected patients 1 of 8 (%12,5) had sustained response following treatment. At the end of treatment, although Na+, K+ ATPase was restored in both of the patients groups, relative changes in enzyme activity in relation to relative reduction in ALT levels as a response to IFN therapy were not correlated.