Gold-hyaluranic acid micromotors and cold atmospheric plasma for enhanced drug delivery and therapeutic applications.

Micro/nanomotors have emerged as promising platforms for various applications, including drug delivery and controlled release. These tiny machines, built from nanoscale materials such as carbon nanotubes, graphene, metal nanoparticles, or nanowires, can convert different forms of energy into mechanical motion. In the field of medicine, nanomotors offer potential for targeted drug delivery and diagnostic applications, revolutionizing areas such as cancer treatment and lab-on-a-chip devices. One prominent material used in drug delivery is hyaluronic acid (HA), known for its biocompatibility and non-immunogenicity. HA-based drug delivery systems have shown promise in improving the efficacy and reducing the toxicity of chemotherapeutic agents like doxorubicin (DOX). Additionally, micro/nanomotors controlled by external stimuli enable precise drug delivery to specific areas of the body. Cold atmospheric plasma (CAP) has also emerged as a promising technology for drug delivery, utilizing low-temperature plasma to enhance drug release and bioavailability. CAP offers advantages such as localized delivery and compatibility with various drug types. However, further research is needed to optimize CAP drug delivery systems and understand their mechanisms. In this study, gold-hyaluronic acid (Au-HA) micromotors were synthesized for the first time, utilizing acoustic force for self-motion. The release profile of DOX, a widely used anticancer drug, was investigated in pH-dependent conditions, and the effect of CAP on drug release from the micromotors was examined. Following exposure to the CAP jet for 1 min, the micromotors released approximately 29 µg mL-1 of DOX into the PBS (pH 5), which is significantly higher than the 17 µg mL-1 released without CAP. The research aims to minimize side effects, increase drug loading and release efficiency, and highlight the potential of HA-based micromotors in cancer therapy. This study contributes to the advancement of micro-motor technology and provides insights into the utilization of pH and cold plasma technology for enhancing drug delivery systems.

Chitosan functionalized gold-nickel bimetallic magnetic nanomachines for motion-based deoxyribonucleic acid recognition.

In this present study, the preparation of chitosan functionalized gold­nickel wire nanomachines (nanomotors) (CS@Au-Ni NMs) for motion-based double-stranded deoxyribonucleic acid (dsDNA) recognition and detection was described. Synthesis of the nanomachines was accomplished by Ni layer formation using direct current (DC) magnetron sputtering over electrochemically deposited Au wires. Subsequently, biopolymer chitosan was dispersed onto this bimetallic layer by drop casting which could provide a novel and functional surface for leading bio-applications. CS@Au-Ni NMs were characterized via scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and zeta potential analysis methods for the elucidation of structural morphology, elemental composition and electrophoretic mobility. On account of presenting the application of these magnetic nanomachines, they were interacted with different concentrations of dsDNA and the changes in their velocities were investigated. The speed CS@Au-Ni NMs were measured as 19 µm/s under 22 mT magnetic field. These magnetically guided nanomachines demonstrated a practical and good sensing ability by recognizing dsDNA between 0.01 mg/L and 10 mg/L. Electrochemical characterization was also performed to identify the surface characteristics. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) experiments presented the interaction of the NMs with dsDNA by indicating the convenient recognition.

Fluorescence Detection of miRNA-21 Using Au/Pt Bimetallic Tubular Micromotors Driven by Chemical and Surface Acoustic Wave Forces.

In this study, surface acoustic wave (SAW) systems are described for the removal of molecules that are unbound to micromotors, thereby lowering the detection limit of the cancer-related biomarker miRNA-21. For this purpose, in the first step, mass production of the Au/Pt bimetallic tubular micromotor was performed with a simple membrane template electrodeposition. The motions of catalytic Au/Pt micromotors in peroxide fuel media were analyzed under the SAW field effect. The changes in the micromotor speed were investigated depending on the type and concentration of surfactants in the presence and absence of SAW streaming. Our detection strategy was based on immobilization of probe dye-labeled single-stranded probe DNA (6-carboxyfluorescein dye-labeled-single-stranded DNA) to Au/Pt micromotors that recognize target miRNA-21. Before/after hybridization of miRNA-21 (for both w/o SAW and SAW streaming conditions), the changes in the speed of micromotors and their fluorescence intensities were studied. The response of fluorescence intensities was observed to be linearly varied with the increase of the miRNA-21 concentration from 0.5 to 5 nM under both w/o SAW and with SAW. The resulting fluorescence sensor showed a limit of detection of 0.19 nM, more than 2 folds lower compared to w/o SAW conditions. Thus, the sensor and behaviors of Au/Pt tubular micromotors were improved by acoustic removal systems.

RF plasma-enhanced conducting Polymer/W5O14 based self-propelled micromotors for miRNA detection.

Functionalized micro/nanomotors having immobilized biological molecules provide excellent and powerful tools for the detection of target molecules. Based on surface modifications and mobilities of micromotors, we report herein a new experimental design of high-speed, self-propelled and plasma modified micromotors for biomedical applications. Within this scope, in the first step, poly (3,4-ethylenedioxythiophene) (PEDOT) was in-situ synthesized onto W5O14 (tungsten trioxide) wires by using radio frequency (RF) rotating plasma reactor. Then, W5O14/PEDOT-Platinum (Pt) hybrid micromotors were fabricated by using magnetron sputtering technique. The detection of miRNA-21 was performed using both single-stranded DNA (ssDNA) (probe DNA) immobilized W5O14-Pt and W5O14/PEDOT-Pt micromotors. The fluorescence signals were determined after hybridization of probe DNA immobilized these novel W5O14-Pt and W5O14/PEDOT-Pt micromotors with different molar concentrations of the synthetic target (6-carboxyfluorescein dye (FAM)-labeled miRNA-21). The changes in the micromotor speeds after the hybridization process were also evaluated. W5O14/PEDOT-Pt micromotors presented better sensor properties compared to the W5O14-Pt micromotors. A good linearity for miRNA-21 concentration between 0.1 nM and 100 nM was obtained for these micromotors based on their fluorescence intensities. The detection limit was found as 0.028 nM for W5O14/PEDOT-Pt micromotors (n = 3). Thus, sensor and motor characteristics of the W5O14-Pt micromotors were improved by RF plasma enhanced PEDOT coatings. The new catalytic W5O14 based micromotors demonstrated here had great potential for the development of sensitive and simple sensing platforms for detection of miRNA-21.

Target-controlled infusion of remifentanil with propofol or desflurane under bispectral index guidance: quality of anesthesia and recovery profile.

BACKGROUND: Our objective was to examine the clinical properties of two anesthetic regimens, propofol target-controlled infusion (TCI), or desflurane using remifentanil TCI under bispectral index (BIS) guidance during ear, nose, and throat (ENT) procedures. METHODS: FORTY CONSENTING PATIENTS WHO SCHEDULED FOR ENT PROCEDURES WERE PROSPECTIVELY STUDIED AND WERE INCLUDED IN ONE OF THE TWO GROUPS: TCI group or desflurane (DES) group. General anesthesia was induced with 3 ng mL(-1) and 4 µg mL(-1) effect site concentrations (Ce) of remifentanil and propofol, respectively, with TCI system. After intubation, while propofol infusion was continued in the TCI group, it was ceased in the DES group and desflurane with an initial delivered fraction of 6% was administered. The Ce of propofol infusion and inspired fraction of desflurane was adjusted in order to keep BIS as 50 ± 10. RESULTS: General mean values of mean arterial pressure (MAP) and heart rate (HR) for the TCI group was significantly higher than DES group (89.3 mmHg and 72.4 bpm vs. 77.1 mmHg and 69.5 bpm). Early emergence from anesthesia did not significantly differ between the groups. The rate of patients' Aldrete score (ARS) to reach 10 was found to be 100% at the 15(th) min in both groups. CONCLUSIONS: Bispectral index guided combinations of remifentanil TCI either with propofol TCI or desflurane anesthetic regimens are both suitable for patients undergoing ENT surgery. The lower blood pressure in the remifentanil TCI with desflurane anesthetic regimens may be a significant advantage.

Remifentanil versus fentanyl compared in a target-controlled infusion of propofol anesthesia: quality of anesthesia and recovery profile.

PURPOSE: The aim of the present study was to compare the clinical properties of fentanyl versus remifentanil in a target-controlled infusion (TCI) of propofol anesthesia regimen with bispectral index (BIS) monitoring. METHODS: Forty consenting patients scheduled for elective septorhinoplasty were prospectively studied as one of two groups: fentanyl (group F) or remifentanil (group R). After loading boluses of fentanyl 3 microg kg(-1) or remifentanil 1 microg kg(-1) were administered, the continuous infusion of fentanyl or remifentanil was started at a rate of 0.03 or 0.15 microg kg(-1) min(-1), respectively. Propofol infusion was then commenced with a 3 microg ml(-1) effect site concentration (Ce) by means of a TCI device. The Ce propofol was adjusted to keep BIS at 50 +/- 10. RESULTS: The general mean value of propofol Ce for group F and group R was 4.0 and 3.5 microg ml(-1), respectively. As to the recovery profile, the eye opening time (mean, 6.7 vs. 4.6 min), extubation time (mean, 7.3 vs. 4.7 min), and orientation time (mean, 7.6 vs. 4.9 min) were found to be significantly longer in group F than in group R. CONCLUSION: We concluded that in propofol-based TCI anesthesia under BIS supervision for septorhinoplasty operations, remifentanil was better than fentanyl, especially with respect to emergence from total intravenous anesthesia (TIVA). Furthermore, the durations of anesthesia and operation were rather short, which indicates that fentanyl can be safely used.