Nanoscience & Nanotechnology-Asia - Volume 7, Issue 1, 2017

Nanomedicine is a new field of medicinal science in which nanotechnology has found its way into medicine. Nanoantibiotics should be the main focus due to the growing amount of ‘superbugs’ or multi-drug resistant bacteria as one of the major clinical problems all around the globe. Biological production of nanoparticles has found its greatest application towards medicine and mainly in drug delivery systems. These highly-targeted nanoparticles that can be able to deliver higher doses of available antibiotics could possibly overcome the problem of drug-resistant bacteria in near future. Nanoantibiotics could improve the scheme of dosage based targeted therapy as well as combination studies are being done between nanoparticles and antibiotics. This non-traditional method also provides a very less opportunity for pathogens to develop resistance because of availability of different groups and different targets of nanoparticles. This review focuses on nanoparticles that can potentially be used to tackle this problem of drug resistant bacteria.

Nanotechnology plays a prominent role virtually in every field of science and technology, especially in the drug delivery systems. Nanoparticles (NPs) possess unique advantages over the existing strategies prevailed in biomedical applications but, they face certain challenges including its synthesis from expensive synthetic routes and use of toxic reagents. Till date, most of the approaches focused on the synthesis of NPs from nonbiological sources and its application is limited due to its toxicity and instability in biological systems. Biogenic NPs paved a ray of hope in the establishment of a new era with ecofriendly nanoparticles in medical sciences particularly in drug delivery, bio-imaging and other therapeutic approaches. The preparation of NPs using biological materials is described under “green chemistry” approach; which is a philosophy of chemical research and engineering that encourages the design of products and processes that minimize the use and generation of hazardous substances through smarter production. Past decade saw a large number of significant developments with the application of biogenic NPs in the field of oncology. Various materials of biological origin offer unique promising features to tailor biogenic NPs with predefined properties. The current review describes about the recent developments in the synthesis and significance of biogenic NPs in the management of various clinical abnormalities especially cancer. By drawing diverse toolset for generation of NPs from inexpensive biological source, this article exploits high impact application of these NPs in biomedical field.

The aim of the present study is to develop and formulate a nanoparticulate carrier for sustained and ocular delivery of Fluconazole and to study its in-vitro release characters. Chitosan nanoparticles of Fluconazole were formulated by spontaneous emulsification and cross-linking method. The mean particle size, drug loading capacity, invitro release profile and release kinetics were studied. The antifungal efficacies of nanospheres were compared with conventional eye drops by cup-plate method. The average particle size was found to be 152.85±13.7nm. The drug loading capacity of all drug loaded nanoparticles was found to be optimum (≤50%). The in-vitro release study revealed the zero order kinetics and Higuchi’s diffusion mechanism. The drug bound nanoparticles exhibited good in-vitro antifungal effect in comparison with conventional eye drops. The formulated nanoparticles were found to be a suitable carrier for sustained ocular delivery of Fluconazole in terms of optimum drug loading, sustained release characters and antifungal activity.

In this paper, SnS2/gold nanoparticle (SnS2/GNs) hybrids were synthesized by a facile solvothermal route. A highly sensitive hydrogen peroxide sensing was then developed based on the SnS2/GNs hybrid nanomaterials. The obtained porous structure of the SnS2/GNs hybrid exhibited excellent electrocatalytic activity towards the reduction of H2O2. The fabricated biosensor exhibits good electrochemical activity for H2O2 with a comparable linear range from 1 µmol/L to 2785 µmol/L and low detection limit of 0.33 µmol/L. Moreover, the modified electrode displayed good stability and reproducibility. The current work provides a feasible platform to fabricate a variety of non-enzymatic biosensors.

Nano pesticides are the best way to conventional pesticides. Nano pesticides can provide better penetration and accelerate resistance of microbes through the plant and control different diseases. Nano formulation of pesticides certainly protects the premature degradation in the environment and delivers high impact on targeted species. In this communication, we reported a novel nano-acephate for plant disease control and its subsequent characterization of encapsulated complex using polypropylene glycol as an encapsulated agent. Nano-acephate encapsulated particles were characterized by dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). The bioactivity study was conducted against various fungi and bacteria. The performance of Nano particles was many fold times effective when compared to the original parental particles. The bio-assay of Nano acephate shows better results when compared to the normal commercial acephate. Less environmental contamination and safe handling are the advantages of nano-pesticides. This method is an eco-friendly formulation and it is useful to farmers.

Recently human resistance to external pathogen has led to the development of anti-bacterial wound dress, accordingly, the development of anti-bacterial wound dress using nano-Zinc oxide matrix has been examined. ZnO in nanoparticles morphological structure was synthesized using hydrothermal technique and were directly immobilized into polymer blend matrix composed of alginate-PVA. The hybrid mixture was fabricated by casting solvent evaporation into membrane film. The influence of variable ZnO amounts blended with the polymeric matrix in different weight ratios from 5% to 30% W/V on the fabricated composite membrane films was examined. The mechanical properties of the fabricated zinc oxide membranes were compared using the tensile test Machine to select the best concentration of incorporated zinc oxide nanoparticles into the polymer blend. The most properly prepared membrane was characterized using SEM, XRD, FT-IR and TGA. The most proper mechanical properties of ZnO polymeric membrane nanocomposite were recorded at blending ratio of 20% W/V. Both the XRD and FT-IR analyses indicated that possible interaction may be established between polymers and nanoparticles above the optimum blending ratio of 20% W/V declining the fabricated membrane mechanical properties. The antibacterial activity of the prepared membranes was assessed qualitatively by colony forming units (CFU) measurements. The antibacterial activity demonstrated a significant antibacterial activity against Staphylococcus aureus and Escherichia coli. This antibacterial activity was improved by increasing the incorporation of ZnO nanoparticle concentration in the composite membrane.

In this paper, we present an organic synthesis method used for the synthesis of high quality Cadmium Selenide (CdSe) and Zinc Selenide (ZnSe) semiconductor nanocrystals. The mixture of hexadecylamine (HDA)-tetradecylphosphonic acid (TDPA), trioctylphosphine oxide (TOPO)-trioctylphosphine (TOP) has been used as stabilizing solvent for synthesis of high quality CdSe and ZnSe nanocrystals. These QDs have been characterized using various techniques like X-ray diffraction, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) for size and morphology of samples. Fourier transform infrared spectroscopy has been used for the identification of functional groups, UV-visible absorption and Fluorescence spectroscopy for optical characteristics. These studies show that the particle size is in 2-5 nm range with cubic crystalline phase. The band gap of 3.5 and 4.5 eV has been calculated for CdSe and ZnSe nanocrystals by using Tauc relation. Effective mass approximation calculation and blue shift of photoluminescence peak also confirms the narrow size of particles. The objective of this work is to produce size controlled CdSe and ZnSe nanocrystals with organic passivated surface having high luminescence for use in different optoelectronic applications.

The aim of the present study was to develop solid lipid nanoparticles (SLN) of albendazole (ABZ) and evaluate its efficacy in mice model after oral administration. Various solid lipids were screened on the basis of solubility of the drug. SLN of ABZ were prepared by phase inversion temperature method using Compritol 888 ATO as a lipid with Cremophor EL and Tween 80 as surfactants. Effect of lipid concentration and drug con- centration on mean particle size and entrapment efficiency was evaluated. Optimized formulation was characterized by Transmission electron microscopy (TEM), Differential scanning calorimetry (DSC), and X-ray diffraction (XRD). In vitro drug release was evaluated using dialysis bag diffusion technique. The anthelmintic efficacy of ABZ-SLN was evaluated in mice infected with Toxocara canis larvae. The mean particle size of ABZ-SLN was found to be in the range of 116±3.51 nm - 168.3±3.92 nm and entrapment efficiency wer e found to be in the range of 82.99±2.22% -89.72±1.95% depending on the drug concentration. TEM analysis revealed that nanoparticles were almost geometrical in shape. DSC thermograms and XRD pattern revealed amorphinization of ABZ in SLN matrix. In vitro drug release profile of ABZ-SLN in simulated gastrointestinal conditions demonstrated a prolonged release pattern wherein maximum release was found to be 92.66±1.7% in 24hr. The anthelmintic efficacy study confirmed the reduction in larvae count in the liver, lung, brain and kidney. Based on the results it can be concluded that solid lipid nanoparticles of ABZ could be a promising formulation for the treatment of Toxocara canis infection.

In this present study Aspirin loaded alginate nanoparticles were prepared by desolvation technique using acetone and ethanol as desolvating agents. Continuous and intermittent addition methods were adapted for the addition of desolvating agent to the aqueous solution. Two formulations were prepared by using each desolvating agent. F1 and F3 were prepared by continuous addition of acetone and ethanol as desolvating agents. F2 and F4 were prepared by intermittent addition of acetone and ethanol as desolvating agents. In all the Formulations, particles were found to be nanometric in size. Comparative study was made among these four Formulations for particle size, Mean particle diameter, Product yield, Drug content,Electrophoretic mobility, Zetapotential, Entrapment efficiency, Loading capacity. Dissolution studies were performed for all the four formulations and compared for better dissolution profile. Comparative study was made to determine the most appropriate desolvating agent and best method for the preparation of alginate nanoparticles. Among all Formulations Intermittent addition of ethanol was showing better result with Mean particle diameter of 237.4 nm, Entrapment efficiency of 37.4 %, Loading capacity of 10.22 %. The Zeta potential value (-52.3) was higher than all other Formulations. Based on these results it was concluded that intermittent addition method was the best method and ethanol was the better desolvating agent for the preparation of aspirin nanoparticles.

Green synthesis of silver nanoparticles (AgNPs) was successfully developed by using Ephedra intermedia stem extract. The effect of silver precursor concentration, amount of stem extract, and reaction temperature on the bioreduction reaction was evaluated. Natural carbohydrates present in Ephedra intermedia were found to act as an effective reducing and capping agent during AgNPs biosynthesis. AgNPs were characterized by UV-vis spectroscopy, TEM, XRD, FTIR and DLS analysis. The particles were crystalline and spherical in shape having diameters between 10 and 36 nm, the mean diameter being 24 nm. Zeta potential of the prepared nanoparticles was measured to be -30 mV which is an acceptable charge for colloid particles.

The chemical method is one of the most promising routes for the production of multi-walled carbon nanotubes. In this study, multi-walled carbon nanotubes (MWCNTs) were successfully synthesized by the modified Staudenmaier method. MWCNTs were synthesized using graphite powder at room temperature. This process does not utilize any metal catalyst. The prepared multi-walled carbon nanotubes were characterized for their crystalline, structural and thermal stability properties. The structural, crystalline and morphological characterization of The produced MWCNTs were performed by using scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction (XRD), thermogravimetric analysis(TGA), Raman analysis, and atomic force microscopy( AFM). Crystallinity and graphitization degree was observed for the produced MWCNTs have a diameter of 13.1 nm. The yield is approximately 10% of the carbon source (graphite). Moreover, the obtained MWCNTs have high thermal stability and oxidation resistance lower than 401.80 °C. The present approach provides a simple low cost and easy method of MWCNTs synthesis.