Creation of Nanorobots: Both State-of-the-Science and State-of-the-Art

Over the last decade, remarkable achievements in nanofabrication technology has led to the development of hybrid intelligent systems including the nanomechanical devices powered by the chemical energy sources or biomolecular motors. In this context, nanorobotics has emerged as a highly-advanced technology for designing the fully functional smart devices or robots at nano scale. Development of these highly-controlled and functional nanostructures for sensing, information processing, signaling, and actuation may provide remarkable breakthroughs in medicine such as the improved imaging or targeted therapeutic interventions. Besides the detection and destroying the toxic materials and ecosystem restoration, the stimuli-responsive nanorobots may be used for the diagnosis or treatment of cardiac disorders, traumatic injuries, diabetes, and bacterial or viral infections. These molecular tools with nanoscale resolution facilitates early diagnosis in cancer and precise localization of anticancer agents leading to the minimal side effects. Nanorobots may easily traverse the human body and repair the cells or assist an improper functioning organ. These tiny devices integrated with wireless locomotion, external or internal power supply, artificial intelligence, and smart sensors may also be used for targeted delivery of genes or drugs into the single cells or tissues, tele-operation, or patient monitoring. Indeed, development of the medical nanorobots with a wide range of capabilities is a proof of concept and art in modern science and a breakthrough in nanotechnology which has been highlighted in the present manuscript

Resveratrol: More than a phytochemical

In recent years, alternative and complementary medicine including the plant-based drugs with antioxidant and neuroptotective effects has attracted a growing interest. Resveratrol, a polyphenolic compound which is found in various plant species, has emerged as a promising nutraceutical with therapeutic potentials in neuropsychiatric, cardiometabolic and cancer diseases, also aging. The abundance of research providing promising findings about the multi-spectrum therapeutic applications of resveratrol and its encouraging potential to treat or prevent chronic and age-related disorders has raised a considerable number of clinical trials. Recently, resveratrol is implicated the biology of nerve growth factor (NGF), a critical player in the maintenance of neuronal growth and function. Furthermore, resveratrol affects the endocannabinoid signalling (eCBs) which exerts modulatory effects in the survival signalling pathways, neural plasticity, and a variety of neuroinflammatory and neurodegenerative processes. The therapeutic effects of this ubiquitous signalling system in Alzheimer`s disease, epilepsy, multiple sclerosis, mood and movement disorders, spinal cord injury, and stroke have been well-documented. In the present review, the implication of NGF and eCBs in the mechanism of action of resveratrol, that may be of therapeutic significance in neurological and non-neurological disorders, is highlighted. Biomed Rev 2015; 26: 13-21

Application of Carbon Nanotubes for Controlled Release of Growth Factors or Endocannabinoids: A Breakthrough in Biomedicine

Carbon nanotubes, the nanostructures with immense potential in various scientific fields such as the regenerative medicine, have emerged as innovative nanosreservoirs with multimodal functionality and application in theranostic sessions. The superior mechanical properties, high thermoelectrical conductivities, or improved solubility and biocompatibility have made CNTs as suitable candidates for biosensing, high-resolution imaging, tissue-engineering, and delivery of a variety of compounds with poor solubility or short half-life. These advanced nanovectors which promote neuronal growth and functional connectivity, have shown great theranostic potential in the central nervous system disorders. Several pioneering works have shown the ability of CNTs for controlled release of drugs or growth factors into the brain. Over the last decade the neurotropic and metabotrophic effects of nerve-growth factor, brain-derived neurothropic factor and endocannabinoid system and their involvement in the mechanism of action of a wide variety of drugs have been the focus of intense research. In order to overcome the rapid degradation and/or non-specific distribution of nerve-growth factor or endocanabinoids, conjugation with CNTs has led to the prolonged effects of these modulating factors. Based on their unique properties, the appropriate application of functionalized CNTs may indeed revolutionize the current biomedical interventions that has been highlighted in the present review

Nanoparticles reshape the biomedical industry

Over the last decades, increasing interest has been attracted towards the nanotechnology which provide a set of promising research tools and theranostic approaches. Tremendous research efforts in nanofabrication technology have led to the production of biocompatible nanostructures and advanced carriers with various configurations for protection of the loaded biomolecules or drugs against the metabolism or excretion. Furthermore, controlled delivery and targeted therapy may result in the improved therapeutic effects against a variety of diseases and reduced adverse effects of drugs. The efficiency of protein drugs may be negatively affected by their limited transportation within the body and short half-lives. Application of nanoparticles may significantly improve the pharmacological profiles of protein drugs. In neurology, high-resolution imaging techniques, nanoengineered materials capable of interaction with the nervous systems, and nanopharmaceuticals with minimal toxicity and improved bioavailability may be of great theranostic significance. This may provide remarkable breakthroughs in the pharmaceutical industry and health-care system. In the present review, the significance of nanotechnology and modeling approaches in health-care system has been highlighted

Thiolated chitosan nanoparticles as a delivery system for antisense therapy: evaluation against EGFR in T47D breast cancer cells

Thiolated chitosan has high transfection and mucoadhesive properties. We investigated the potential of two recently synthesized polymers: NAC-C (N-acetyl cysteine-chitosan) and NAP-C (N-acetyl penicillamine-chitosan) in anticancer drug delivery targeting epidermal growth factor receptor (EGFR). Doxorubicin (DOX) and antisense oligonucleotide (ASOND)-loaded polymer nanoparticles were prepared in water by a gelation process. Particle characterization, drug loading, and drug release were evaluated. To verify drug delivery efficiency in vitro experiments on a breast cancer cell line (T47D) were performed. EGFR gene and protein expression was analyzed by real time quantitative polymerase chain reaction and Western blotting, respectively. A loading percentage of 63% ± 5% for ASOND and 70% ± 5% for DOX was achieved. Drug release data after 15 hours showed that ASOND and DOX were completely released from chitosan-based particles while a lower and more sustained release of only 22% ± 8% was measured for thiolated particles. In a cytosol simulated release medium/reducing environment, such as found intracellularly, polymer-based nanoparticles dissociated, liberating approximately 50% of both active substances within 7 hours. ASOND-loaded polymer nanoparticles had higher stability and high mucoadhesive properties. The ASOND-loaded thiolated particles significantly suppressed EGFR gene expression in T47D cells compared with ASOND-loaded chitosan particles and downregulated EGFR protein expression in cells. This study could facilitate future investigations into the functionality of NAP-C and NAC-C polymers as an efficient ASOND delivery system in vitro and in vivo

Chitosan–Pluronic nanoparticles as oral delivery of anticancer gemcitabine: preparation and in vitro study

Nanoparticles have proven to be an effective delivery system with few side effects for anticancer drugs. In this study, gemcitabine-loaded nanoparticles have been prepared by an ionic gelation method using chitosan and Pluronic® F-127 as a carrier. Prepared nanoparticles were characterized using dynamic light scattering, Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscopy, and transmission electron microscopy. Different parameters such as concentration of sodium tripolyphosphate, chitosan, Pluronic, and drug on the properties of the prepared nanoparticles were evaluated. In vitro drug release was studied in phosphate-buffered saline (PBS; pH = 7.4). The cytotoxicity of the nanoparticles was assayed in the HT-29 colon cancer cell line. The mucoadhesion behavior of the nanoparticles was also studied by mucus glycoprotein assay. The prepared nanoparticles had a spherical shape with positive charge and a mean diameter ranging between 80 to 170 nm. FT-IR and DSC studies found that the drug was dispersed in its amorphous form due to its potent interaction with nanoparticle matrix. Maximum drug encapsulation efficiency was achieved at 0.4 mg/mL gemcitabine while maximum drug loading was 6% obtained from 0.6 mg/mL gemcitabine. An in vitro drug release study at 37°C in PBS (pH = 7.4) exhibited a controlled release profile for chitosan–Pluronic® F-127 nanoparticles. A cytotoxicity assay of gemcitabine-loaded nanoparticles showed an increase in the cytotoxicity of gemcitabine embedded in the nanoparticles in comparison with drug alone. The mucoadhesion study results suggest that nanoparticles could be considered as an efficient oral formulation for colon cancer treatment

Priprava želatinksih mikrosfera s mliječnom kiselinom: Učinak umrežavanja na oslobađanje ljekovite tvari

In this study, gelatin microspheres containing lactic acid were prepared by the polymerization technique using glutaraldehyde as the cross-linking agent. Dried microspheres were loaded by immersing them in an aqueous solution of lactic acid. In order to prepare microspheres with an appropriate drug release profile, the effect of time of cross-linking and the amount of cross-linking agent on the swelling properties of microspheres and their release profile were investigated. The microencapsulation efficiency, microspheres appearance, particle size, swelling ratio and drug release profile were also studied. Microspheres prepared with a larger amount of crosslinking agent, or after longer crosslinking time, showed a reduced swelling ratio in aqueous media. In vitro release pattern of lactic acid from gelatin microspheres showed a biphasic profile and the release rates were reduced upon increasing the amount of cross-liking agent and prolonging the cross-linking time.U radu je opisana priprava želatinskih mikrosfera s mliječnom kiselinom metodom polimerizacije koristeći glutaraldehid kao sredstvo za umrežavanje. Osušene mikrosfere su uronjene u vodenu otopinu mliječne kiseline. Ispitivan je utjecaj vremena umrežavanja i količine sredstva za umrežavanje na bubrenje mikrosfera i njihov profil oslobađanja. Također je proučavan izgled mikrosfera, veličina čestica, bubrenje i profil oslobađanja ljekovite tvari. Mikrosfere pripravljene s većim sadržajem sredstva za umrežavanje ili uz produljeno vrijeme umrežavanja, u vodenom mediju manje bubre. Oslobađanje mliječne kiseline iz želatinskih mikrosfera in vitro je bifazičnog profila, a smanjuje se ako je tijekom priprave povećana količina sredstva za umrežavanje i produljeno vrijeme umrežavanja. Mikrosfere s odgovarajućim profilom oslobađanja ljekovite tvari mogu se pripraviti podešavanjem ta dva faktora tijekom priprave mikrosfera

Priprava želatinksih mikrosfera s mliječnom kiselinom: Učinak umrežavanja na oslobađanje ljekovite tvari

In this study, gelatin microspheres containing lactic acid were prepared by the polymerization technique using glutaraldehyde as the cross-linking agent. Dried microspheres were loaded by immersing them in an aqueous solution of lactic acid. In order to prepare microspheres with an appropriate drug release profile, the effect of time of cross-linking and the amount of cross-linking agent on the swelling properties of microspheres and their release profile were investigated. The microencapsulation efficiency, microspheres appearance, particle size, swelling ratio and drug release profile were also studied. Microspheres prepared with a larger amount of crosslinking agent, or after longer crosslinking time, showed a reduced swelling ratio in aqueous media. In vitro release pattern of lactic acid from gelatin microspheres showed a biphasic profile and the release rates were reduced upon increasing the amount of cross-liking agent and prolonging the cross-linking time.U radu je opisana priprava želatinskih mikrosfera s mliječnom kiselinom metodom polimerizacije koristeći glutaraldehid kao sredstvo za umrežavanje. Osušene mikrosfere su uronjene u vodenu otopinu mliječne kiseline. Ispitivan je utjecaj vremena umrežavanja i količine sredstva za umrežavanje na bubrenje mikrosfera i njihov profil oslobađanja. Također je proučavan izgled mikrosfera, veličina čestica, bubrenje i profil oslobađanja ljekovite tvari. Mikrosfere pripravljene s većim sadržajem sredstva za umrežavanje ili uz produljeno vrijeme umrežavanja, u vodenom mediju manje bubre. Oslobađanje mliječne kiseline iz želatinskih mikrosfera in vitro je bifazičnog profila, a smanjuje se ako je tijekom priprave povećana količina sredstva za umrežavanje i produljeno vrijeme umrežavanja. Mikrosfere s odgovarajućim profilom oslobađanja ljekovite tvari mogu se pripraviti podešavanjem ta dva faktora tijekom priprave mikrosfera

Trace Detection of Diphenhydramine by Adsorption on a Microelectrode at Flow Injection System by Fast Fourier Transform Continuous Cyclic Voltammetry

A continuous cyclic voltammetric study of diphenhydramine at gold micro electrode was carried out. Some investigations were also done to find the effects of various parameters on the sensitivity of the proposed method. The experiments were performed under the following conditions: pH = 2, the scan rate = 40 V/ s (v), accumulation potential = 500 mV (E), and accumulation time = 0.2 s (t). The drug in phosphate buffer (pH = 2.0) is adsorbed at optimized condition on the surface of electrode, giving rise to change in the current of well-defined oxidation peak of gold in the flow injection system. The proposed detection method is a very fast and appropriate technique for determination of the drug compound in a wide variety of chromatographic analysis methods. Signal-to-noise ratio has significantly increased by application of discrete Fast Fourier Transform (FFT) method, background subtraction and twodimensional integration of the electrode response over a selected potential range and time window. The linear concentration range was from 4.0 × 10–7 to 1.0 × 10–11 mol dm–3 (r = 0.9987) with a limit of detection and quantitation 5 × 10–12 and 4 × 10–11 mol dm–3, respectively. The method has the requisite accuracy, sensitivity, precision and selectivity to assay diphenhydramine in tablets