Current Nanomedicine - Volume 7, Issue 1, 2017

Background: Silver nanofabricated products are well known elements from ages, and have great demand at present due to their massive significance in therapeutics, diagnostics, theranostics and targeted drug delivery systems. Silver nanoparticles (AgNPs) came into limelight, owing to their diverse pharmacotherapeutic potentials such as antiproliferative, anti-infective, anti-inflammatory, anti-coagulant etc. This resulted in increased commercial production of AgNPs and Ag-related products at highest pace. In majority of commercial AgNP production, traditionally wet chemical reduction techniques are employed that utilize chemicals that are non-ecofriendly, produce by-products, emit harmful substances and are expensive. Plant extracts are most environment friendly, easily available and are economically viable. The biological mediated approach serves as the most promising alternative to synthesize size-controlled AgNPs commercially. Method: We undertook a search of bibliographic and patent databases for peer-reviewed research literature using a conceptual framework. The quality screened papers and patents were classified, judged and included for the study. Result: The study revealed that AgNPs have potential as nanomedicine owing to their diverse activity. About 91 different plants and 16 patented methods were highlighted along with mechanism of actions for the fabrication of nanoparticles. Conclusion: This article exclusively focuses on simple, environment friendly, size/shapecontrolled synthesis of AgNPs using plant extracts and highlights the knowledge of existing plant resources for producing nanomaterials.

Background: CNS disorders have reached a concerning number globally. While a lot of research is being encouraged, there are not many drugs in the market to combat the severity of Alzheimer’s or Parkinson’s diseases. Most of the drugs used for the management of these diseases have poor solubility, low hydrophilcity and cannot reach the target owing to the Blood-Brain-Barrier (BBB). Due to these problems, science involving nanotechnology is now being used to formulate drug delivery systems to permeate through the barrier and deliver the drug at the target. Methods: This mini review analyses the work of various scientists and research groups in this field and discusses the significance of nanoparticles for drug delivery across the BBB. Formulations that have demonstrated high potential for penetration through the bloodbrain- barrier include Solid Lipid Nanoparticles (SLNs), Polymeric Nanoparticles (PNs), Liposomes and Dendrimers. Along with these formulations, quantum dots have also demonstrated their ability to be used as a diagnostic platform. Results: The management of these conditions at a global level requires efforts from multiple research disciplines along with a diagnostic platform, formulation development and drug delivery techniques. ‘Theranostics’ as an approach for the diagnosis and treatment of the condition and the use of appropriate in vitro/in vivo models have also been discussed to highlight on the importance of multi-disciplinary approach for better understanding of the subject. Conclusion: This mini review discusses the future of some of the most potent nano-sized formulations for the treatment of Alzheimer’s disease. It also reviews the theranostic platforms that can be potentially incorporated in the health care system for the diagnosis and treatment of the condition. The significance of an appropriate animal/3D model for a better understanding of the condition has also been discussed. In a nut shell, this mini review focuses on the nano-particulate systems and the future of nano-medicines for delivering drugs through the barrier for Alzheimer’s Disease (AD).

Anhydrous nanoemulsions are novel colloidal dispersion with a nanosized kinetically stable system for poor aqueous soluble drugs like indomethacin, ibuprofen, cimetidine, phenylbutazone etc. This review deals with the basic concept of development of anhydrous nanoemulsions and vital role of surfactants. In the colloidal dispersion system water replaced with polyols or polar liquid phase which is best suited for water unstable and water sensitive drugs. Due to the larger size of globules or droplets and motility of surfactant in the system, it is capable of incorporating both lipophilic as well as hydrophilic active moieties. Special attention was given to prepare anhydrous preparation with avoidance of aqueous phase in a system and design fresh surfactant combination to achieve stable carrier system for hydrophobic drugs. Dispersion consists of oil, nonaqueous phase and surfactant and mixture of surfactant. Present reviews explored different surfactant and surfactant combination used for the preparation of anhydrous nanoemulsions.

Background: Formulating omega-3-fatty acids as nanoemulsion solves the issues associated with conventional anti-inflammatory formulation by increasing solubilization of the lipophilic moiety, increasing rate of absorption and consequently increasing drug bioavailability. Thus the principal rationale governing the current analysis was to inspect the anti-inflammatory potential of nautical omega-3-fatty acids administered orally as nanoemulsion formulation. Method: Omega-3-fatty acid concentrate was extracted from cod liver oil by urea crystallization method and was further exposed to the various physiochemical evaluation parameters like solubility, partition co-efficient analysis, phytochemical tests and Fourier Transfer Infra-red spectroscopy (FT-IR). The bioactive concentrate was further encapsulated into nanoemulsion formulation by means of phase inversion temperature method and characterized by Scanning electron microscopy (SEM), Particle size and texture evaluations. Wistar albino rats of either sex were selected and divided into prescribed groups and treated with omega-3-fatty acid concentrate, omega-3-nanoemulsion and standard drug Diclofenac sodium respectively and subjected to papaya latex induced rat paw oedema. Result: The percentage difference in the weight of the oedema induced paw for all treatment groups were evaluated and the data obtained was compared. All the data were subjected to due statistical evaluation. The omega-3-nanoemulsion treatment led to a significant (P<0.05) suppression of paw and ear oedema, in carrageen induced paw oedema, croton oil induced oedema respectively. Also the extent of oedema suppression was comparatively more than the suppression observed in case of standard (Diclofenac sodium) treated group and omega-3-fatty acid concentrate treated group which advocate that omega-3- nanoemulsion formulation demonstrates potent anti-inflammatory and analgesic efficacy.

Background: The objective of the present study was to seek out for novel 1, 3, 4-thiadiazole derivatives that would assure to become useful as histamine H3 receptor antagonist. A series of 2 piperidinopiperidine thiadiazole derivatives which were reported as histamine H3 receptor antagonist for the treatment of diabetes chosen for 3D-QSAR study in order to create a quantitative relationship between physiochemical properties and biological behavior of the compounds. Methods: 3D QSAR study by k nearest neighbor molecular field analysis (KNN MFA) method was performed on a series of thiadiazole derivatives as histamine h3 receptor inhibitors by the molecular design suites (VLifeMDS). This study was performed with 21 compounds (data set) using manual selection and random selection method for the splitting up of the data set into training and test set. KNN-MFA methodologies with SW (step wise) variable selection forward-backward, SA (Simulated Annealing) and GA (Genetic Algorithms) methods were used for building the QSAR models. Molecular structures of reported compounds were drawn in the 2 dimensional (2D) Draw app option in the tool menu of V Life MDS QSARPlus. Results: Model 1 was obtained by random selection method for test set and genetic algorithm as a variable selection method. It has been very good internal and the external predictive ability of ~70% and ~80% respectively. According to this model, the field grid points S_1208, E_37, and S_894 representing steric, electrostatic and steric fields respectively, which play a significant role in the determination of biological activity. S_1208 with its negative range (-9.7885 17.6729 2) and position away from indicates the need of more steric groups at R1. E_37 is near R1 and has a negative range (-3.7686 15.3928 2) which directs the need of the negatively ionizable group at this position. S_894 is located near terminal piperidine moiety and has a negative range (-9.6628 9.3234 2) thus signifying the need of a less bulky group for favorable biological activity. Conclusion: This model indicates that one electrostatic and two steric descriptors were involved. The KNN-MFA contour plots provided a further understanding of the relationship between structural features of substituted thiadiazole derivatives and their activities, which should be applicable to design newer potential H3 receptor inhibitors.

Background: Conventional dosage forms of neomycin sulphate suffer from different drawbacks like spillage, poor penetration, low bioavailability, etc. In situ ophthalmic gel can overcome these problems by improving bioavailability, decreasing spillage and diminish the need for recurrent application. Thus, the aim of the present work was to prepare and evaluate in situ ophthalmic gel of neomycin sulphate for sustained ocular delivery. Method: Two polymers, sodium alginate (0.2-0.7%) and HPMC K4M, were used in different concentrations for the preparation of neomycin sulphate insitu gel. The prepared gel was subjected for rheological study, in vitro gelation, drug release study, antimicrobial study by disk diffusion method and others. Result: All formulations were found to be transparent and clear; pH of the formulations was within 6.8 to 6.9; drug content was found within 92-98% in all optimized in situ gelling systems. Viscosity of all formulations decreased as the shear rate increased, which indicated the character of pseudoplastic fluid. Optimized formulations F6 (0.5% Sodium alginate and HPMC K4M 1.5%), F7 (0.3% Sodium alginate and HPMC K4M 1.7%) and F8 (0.4% sodium alginate and HPMC K4M 2%) were liquid before instillation to the eye and underwent rapid gelation upon instillation to the eye. In vitro release through diffusion cell using cellophane membrane for 8 hours revealed sustained release of the drug from sodium alginate polymeric network over 6 hours. Study of antimicrobial efficacy using Pseudomonas aeruginosa for 24 hours showed all formulations to have effective antimicrobial action. Stability study for 6 months had revealed no changes in visual appearance, clarity, pH and % drug content. Conclusion: Hence, from the above results we can conclude that in situ ophthalmic gels of neomycin sulphate can be a good option for the treatment of various bacterial eye infections.

Introduction: Rabies, the most fatal of all infectious diseases, remains a major public health problem in developing countries. The presence of neutralizing and nonneutralizing antiviral antibodies in the serum and cerebrospinal fluid suggests that immune responses are not only responsible for virus clearance but also contribute to pathogenesis revealing the possibility of autoimmunity causing the death. In spite of the developments of costly vaccines, there is no cure for this infection as the drugs etc. do not cross the blood brain barrier to treat the encephalitis in the brain and cerebrospinal and other neural systems. The neuroinvasive functionalized silver nanoparticles with whole viral antigen/ antibodies can neutralize the autoantibody/antigens restoring the neurological dysfunction arise due to autoimmunity. Methods: Commercially available veterinary rabies vaccines were used for functionalization of nanoparticles for all animal studies and for human use commercial human vaccines were used. The immuno-dominant polypeptides for neutralization and bio distribution studies were carried out. The field trial was carried out to rapid dogs, cattle and one human. Results: The present invention - The nanoformulation elicits an optimal immuno protective response against rabies antibody /virus by neutralizing auto immune antibodies/ virus / antigens of rabies infection. The distribution pattern in various tissues and neutralization with these functionalized nanopreparation strongly recommend the use for prophylactic, therapeutic and diagnostics. This novel innovative strategy cures rabies infection which causes 100% mortality within 2 hr to 12 hrs as proved by the field trial report. Discussion: The low cost nanofomulations, in single minimum dosage, with high stability and without cold chain storage could neutralize all the autoantibody/antigens restoring the neurological dysfunction. This novel innovative strategy signifies the birth of a new era in therapeutics for all microbial infections leading to autoimmune diseases.