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Here we fabricated flaxseed oil-based neuronanoemulsions (NNEs) which were further surface-modified with a mucoadhesive polymer, N,N,N‑trimethyl chitosan (TMC) to form mucoadhesive neuronanoemulsions (mNNEs). The NNEs were loaded with high partitioning ropinirole-dextran sulfate (ROPI-DS) nanoplex and fabricated using hot high-pressure homogenization (HPH) technique. NNEs were optimized using Central Composite experimental design. TMC modified mNNE have not been prepared yet for direct nose to brain drug delivery. Here, an objective to provide controlled drug release with prolonged residence on the nasal mucosa for the treatment of Parkinson's disease (PD) is at prime consideration. Enhanced brain targeting through BBB bypass drug delivery, improved therapeutic efficacy through enhanced retention of mNNE formulation over nasal mucosal membrane, reduced dose and frequency of administration, and safety were further expected outcomes of this experiment. The mNNE formulation was subjected to 6 month stability assessment. The mNNE formulation was administered to the Swiss albino mice model via intranasal route and both, the plasma and brain pharmacokinetics were estimated. The in vivo studies performed on mice exhibited high brain targeting efficiency of mNNE formulation through nose to brain delivery via olfactory pathway. The prepared intranasal mNNEs could be on the clinics, if investigated more for behavioral and neurotoxicity studies.

The blood–brain barrier (BBB) is the major obstacle in the effective delivery of neurotherapeutics to the brain microenvironments. The dense membrane hampers the access of many of the therapeutic drugs to reach to the brain regions in sufficient concentrations, leading to poor patient compliance and discontinuation of the neurotherapy. A direct transport of neurotherapeutics from nose to brain regions along the well-known olfactory and trigeminal nerve pathways seems to be an effective strategy to overcome the BBB, and we propose the direct nose-to-brain drug delivery as an effective strategy for safe and noninvasive administration of the neurotherapeutics. Existence of direct entry point from nose to brain encourages the scientists to explore the opportunities in optimizing therapy of neuroailments. This chapter highlights the diagnosis and therapy of major neurodegenerative disorders (NDs) and developments in the nanotechnological areas for effectively delivering the neurotherapeutics to target the neuronal regions via direct nose-to-brain transport.

The brain-blood ratio is an important model correlating the brain-targeting ability of neurotherapeutics with the CNS pharmacokinetics, which need to be presented before the scientific community for exploration of its scientific worth. The purpose of this article is to bring this key concept and its precise discussion to the attention of the researchers.Three major points are discussed herein: First, the significance of brain-blood ratio with respect to investigational neurotherapeutics, and carrier systems and correlation of its research findings with the brain targeting efficiency. Second, the various factors influencing the brain-blood ratio. Third, the various strategies for enhancing the brain-blood ratio. In addition, the benchmark criteria for CNS-likeness of drug molecules and the correlation of brain-blood ratio with brain targeting ability of neurotherapeutics have been tabulated.The brain-blood ratio (also referred to as the brain-plasma ratio) represents one of the tools available today for estimation of CNS pharmacokinetics. It is preferred over other complicated techniques (in situ brain perfusion and microdialysis) due to its ease of use and practicality. We are optimistic that the brain-blood ratio offers an excellent way of evaluating brain-targeting efficiency of neurotherapeutics effectively. In our opinion, it is a very fundamental aspect of brain bioavailability and needs to be presented in a precise way.

The aim of present investigation was formulation and in-vitro evaluation of in situ gel for the nasal delivery of zolmitriptan. The in situ gel was prepared by temperature induced gelation technique using Pluronic with mucoadhesive polymer hydroxy propyl methyl cellulose K4 M in different ratios. The in situ gels so prepared were characterized and from the evaluation studies, batch PH2 was optimized and further subjected for stability studies at 30±2°C and 60±5% RH for 90 days. These formulations retained good stability at accelerated conditions and also did not show any remarkable damage to nasal mucosa in histopathological study. Owing to these properties it can be used as an effective delivery system for the nasal route.

The objective of the present work was to enhance the solubility and dissolution of practically water-insoluble drug raloxifene HCl (RLX), for the same two approaches that were used. In the first approach, drug was kneaded with hydroxypropyl-β-cyclodextrin (HPβCD), and in the second one drug was cogrinded with modified guar gum (MGG). The drug-cyclodextrin complex and drug-MGG cogrind mixtures were characterized by differential scanning calorimetry, X-ray diffraction studies, scanning electron microscopy, and Fourier transform infrared spectroscopy. The solubility and dissolution study reveals that solubility and dissolution rate of RLX remarkably increased in both methods. It was concluded that the prepared inclusion complex showed a remarkable increase in solubility and dissolution of poorly water-soluble drug raloxifene. In the cogrinding mixture, a natural modified gum is used as a surfactant and enhances the solubility and dissolution of RLX without requiring addition of organic solvent or high temperature for its preparation; thus, process is less cumbersome and cost effective. But when both methods were compared; HPβCD complexation method showed significant enhancement of drug solubility.

Dextran sulfate sodium (DS) was allowed to interact ionically with ropinirole hydrochloride (ROPI HCl, an anti-Parkinsonian agent) to synthesize self-assembled ROPI-DS nanoplex. The preliminary objective behind ROPI-DS complexation was to enhance the partitioning of ROPI HCl and thereby its encapsulation into nanocarriers and to improve the nasal membrane permeability. Molecular interactions were computed using in silico molecular modeling. Nanoplex were characterized for physicochemical and partitioning behavior. Optimized ROPI-DS nanoplex was further characterized by spectroscopic and thermal analysis, diffraction studies, morphological and histopathological analysis. In summary, ROPI-DS nanoplex represents a promising nanocarrier material for intranasal administration.

In an attempt to increase oral bioavailability and to target intestinal lymphatic transport system, Nimodipine loaded solid lipid nanoparticles (NMD-SLNs) were prepared. Nimodipine (NMD) is highly lipophilic antihypertensive drug having (logP 3.41) and 13% oral bioavailability. NMD-SLNs were prepared with palmitic acid (PA), poloxamer 188 and soya lecithin as a lipid, surfactant and co-surfactant respectively using high pressure homogeniser. A (2(3)) factorial design was employed; three factors such as lipid, surfactant and co-surfactant concentration were used. Parameters investigated includes particle size, polydispersity index (PDI), zeta potential, drug entrapment efficiency (EE %), drug loading efficiency (LE %), in vitro drug release of the SLNs. Optimised SLNs (F8) had particle size of 116±21 nm, zeta potential of -10±(-4.8) mV, EE of 93.66±9.72% and cumulative drug release of 87.52±2.54% in 10 h. The pharmacokinetic study of optimised SLNs conducted in male Albino Wistar rats showed 2.08-fold increase in relative bioavailability than that of NMD solution, when administered orally. Differential scanning calorimetry study revealed absence of any chemical interaction between NMD and PA while SEM study confirmed the non spherical shape of optimised SLNs. Accelerated stability studies showed that there was no significant change in the mean particle size and PDI after storage at 25±2°C/60±5% RH for the period of three months. Due to enhanced bioavailability, these NMD-SLNs are considered to be promising vehicles for oral delivery.

The aim of the present study was to prepare mucoadhesive multiparticulate system for oral drug delivery using ionic gelation technique. Microspheres of different mucoadhesive polymers including hydroxypropyl methylcellulose (HPMC) K15M and carbopol 971P were prepared. In this technique cross linking of sodium alginate with calcium chloride was done which retarded the release of drug from the mucoadhesive polymer. In the present work atenolol was used as model drug. Interaction studies performed using FT-IR spectroscopy revealed that there was no drug to polymer interactions. Multiparticulates so prepared were discrete, bulky, free flowing and showed an average encapsulation efficiency ranging from 23-74%. Particle size of the multiparticulates as determined by the scanning electron microscopic analysis (SEM) studies was found to be between 561-831 microm. The prepared formulations also exhibited a good mucoadhesive strength which was determined in in vitro conditions through falling film technique. The multiparticulate so prepared also exhibited a good swelling index which confirmed the strong mucoadhesive property of the formulation. Atenolol release from the multiparticulate system was regulated and extended until 12 h and exhibited a non-Fickian anomalous transport from the swellable microspheres, as evident from the release rate exponent values which varied between 0.569-0.622. The stability studies performed on the optimized batch at 40 degrees C/75% RH for 90 d indicated no significant change in the physicochemical properties. In vivo radioimaging studies in rabbits showed the residence of mucoadhesive microspheres for 6-8 h in upper part of gastrointestinal tract (GIT).

An objective of the present study was to develop alginate/hydroxypropyl methylcellulose (HPMC) based floating-mucoadhesive beads of clarithromycin to provide prolonged contact time of antibiotic to treat stomach ulcer. Floating-mucoadhesive beads were prepared and characterized for in vitro performance followed by investigation of ex vivo study in albino-wistar rats. Beads were prepared by ionic gelation technique where calcium chloride used as gelating agent and incorporated liquid paraffin for floating of the beads. Prepared beads were evaluated extensively for particle size, drug entrapment; swelling and surface morphology by using scanning electron microscopy. X-ray radioimaging study in rabbits, in vitro mucoadhesion using rat stomach mucosal membrane and in vitro drug release studies were carried out. Ex vivo performance of alginate-HPMC beads were studied using albino rats in comparison to simple alginate-calcium beads. Alginate-HPMC beads may be suitable floating-muco-adhesive drug delivery system for delivering clarithromycin to treat stomach ulcers.

The objective of this study was to formulate and evaluate the pluronic lecithin organogel containing flurbiprofen for topical application. Different formulations of pluronic lecithin organogels were prepared by using pluronic F127, lecithin, flurbiprofen, isopropyl palmitate, water, sorbic acid, and potassium sorbate. To study the in vitro potential of these formulations, permeation studies were performed with Keshary-Chien diffusion cells. The results of the in vitro permeation studies found that release of flurbiprofen from dialysis membrane-70 was more than excised dorsal rat skin. Gelation temperature study was carried out to determine the temperature where sol-gel transformation takes place. The viscosities of different formulations were determined by using Brookfield Viscometer at 25°C, the viscosity of formulations increases as the lecithin concentration increases. Also the formulations were tested for appearance and feel psychorheologically, pH, and drug content. Interactions between the components of the gel have been investigated by differential scanning calorimetry and X-ray powder diffractometry. The optimized formulation subjected to differential scanning calorimetry shows no drug-polymer interaction. To investigate the in vivo performance of the formulations, a carrageenan-induced rat paw edema model and skin irritation study was used. The stability studies and freeze-thaw thermal cyclic test were carried out, showing no phase separation of gel, and representing gel stability. Statistical analysis of the data of animal study (anti-inflammatory activity) was done by using one way analysis of variance (ANOVA) followed by Dunnett's test. The formulation shows a statistically significant anti-inflammatory activity and is non-irritant to skin.

The objective of this study was to develop a floating, pulsatile, multiparticulate drug delivery system intended for chronopharmacotherapy of arthritis. The floating pulsatile drug delivery has the advantage that a drug can be released in the upper gastrointestinal tract after a definite time period of no drug release, i.e. lag time. Cross-linked beads were prepared using low methoxylated pectin (LM104AS), sodium alginate, and low methoxylated pectin (LM104AS) along with sodium alginate by acid- base reaction during ionotropic gelation. Beads were dried in oven at 50 degrees C for 4 h. Aceclofenac was used as a model drug for encapsulation. Drug loaded multiparticulates were subjected to various characterization and evaluation parameters like entrapment efficiency, surface topography, size analysis and in vitro release study. It was found that calcium pectinate beads show maximum drug entrapment. Hence, pectin containing formulation was further studied for buoyancy, DSC and radio imaging study. Drug release study was performed in acidic environment using pH 1.2 buffer solution for 6 h and then at 7.4 pH for 60 min. The total drug release ranges from 5-10% and 90-94% in acidic and basic media, respectively.

In an experiment to explore the bioadhesion, biocompatibility, and membrane permeation properties, the controlled synthesis of N,N,N-trimethyl chitosan (TMC) was carried out by two-step reductive methylation of chitosan (CHT). Methylation was confirmed by (1)H NMR (δ=3.1 ppm) and FTIR analysis (CH stretch at 1,485 cm(-1)). The TMC was further characterized by DSC, TGA, XRD, HR-TEM, SEM, and elemental analysis. Findings revealed improved solubility, enhanced viscosity, increased swelling index and higher molecular weight of TMC over CHT. Comparative evaluation validated increased bioadhesion potential, and improved ex vivo biocompatibility of TMC compared to CHT. Increased bioadhesion of TMC NPs over CHT NPs can be attributed to the strong electrostatic interactions between cationic amino groups with anionic sialic and sulfonic acid moieties contained in the mucin of the nasal mucus. Ex vivo biocompatibility studies suggested that the NP formulations of both biopolymers were biocompatible and could be applied safely on the nasal epithelium. Ex vivo permeation studies executed on excised cattle nasal mucosa illustrated improved permeability of TMC NPs over CHT NPs. In the author's opinion, two-step reductive methylation of CHT could be an attractive strategy to improve its solubility, bioadhesion, and permeation characteristics without affecting biocompatibility across the mucosal surfaces.

Nose to brain delivery of neurotherapeutics have been tried by several researchers to explore the virtues of this route viz. circumvention of BBB, avoidance of hepatic metabolism, practicality, safety, ease of administration and non-invasiveness. Nanoparticle (NP) therapeutics is an emerging modality for the treatment of Parkinson's disease (PD) as it offers targeted delivery and enhances the therapeutic efficacy and/or bioavailability of neurotherapeutics. This review presents a concise incursion into the nanomedicines suitable for PD therapy delivered via naso-brain transport. Clinical signs of PD, its pathophysiology, specific genetic determinants, diagnosis and therapy involved have been hashed out. Properties of brain-targeting NPs, transport efficacy and various nanocarriers developed so far also been furnished. In our opinion, nanotechnology-enabled naso-brain drug delivery is an excellent means of delivering neurotherapeutics and is a promising avenue for researchers to develop new formulations for the effective management of PD.

The blood-brain barrier (BBB) represents a stringent barrier for delivery of neurotherapeutics in vivo. An attempt to overcome this barrier is represented by the direct transport of drugs from the nose to the brain along the olfactory and trigeminal nerve pathways. These nerve pathways initiate in the nasal cavity at olfactory neuroepithelium and terminate in the brain. An enormous range of neurotherapeutics, both macromolecules and low molecular weight drugs, can be delivered to the central nervous system (CNS) via this route.Present review highlights the literature on the anatomy-physiology of the nasal cavity, pathways and mechanisms of neurotherapeutic transport across nasal epithelium and their biofate and various strategies to enhance direct nose to brain drug delivery. The authors also emphasize a variety of drug molecules and carrier systems delivered via this route for treating CNS disorders. Patents related to direct nose to brain drug delivery systems have also been listed.Direct nose to brain drug delivery system is a practical, safe, non-invasive and convenient form of formulation strategy and could be viewed as an excellent alternative approach to conventional dosage forms. Existence of a direct transport route from the nasal cavity to the brain, bypassing the BBB, would offer an exciting mode of delivering neurotherapeutic agents.

This investigation deals with the intranasal delivery of Valsartan, encapsulated in HPMC-based spray-dried mucoadhesive microspheres, with an aim to provide rapid absorption and quick onset of action for treating hypertension. A 2³-factorial design has been employed for the assessment of influence of three independent variables, namely inlet temperature, feed-flow rate and drug-polymer ratio on production yield, particle size and in vitro drug diffusion of the prepared microspheres. Microspheres were evaluated for particle size, entrapment efficiency, swelling property, in vitro mucoadhesion, in vitro drug diffusion, ex vivo drug permeation, histopathological examination and stability studies. The results of differential scanning calorimetry, X-ray diffraction and scanning electron microscopy revealed molecular dispersion of Valsartan into microspheres with spherical shape and smooth surface. Optimized formulation indicated good mucoadhesion with no severe sign of damage on nasal mucosa. Results of the non-invasive animal studies in dexamethasone-induced hypertensive rat model suggested the suitability of investigated drug delivery system for intranasal administration.

In the present study, tramadol HCl microspheres were designed in order to accomplish rapid delivery of drug to the brain. For this purpose, lower viscosity grade HPMC (E15) was chosen as mucoadhesive polymer and used at different drug/polymer ratios in the microspheres formulations. The spray-dried microspheres were evaluated with respect to the production yield, incorporation efficiency, particle size, mucoadhesive property, in vitro drug release, histopathological study, and radio imaging study in rabbits. DSC and XRD study showed molecular dispersion and conversion of the drug into amorphous form. Size and surface morphology of microspheres was analyzed by SEM and found to be spherical in shape with smooth surface. It was found that the particle size, swelling ability, and incorporation efficiency of microspheres increase with increasing drug-to-polymer ratio. Microspheres show adequate mucoadhesion and do not have any destructive effect on nasal mucosa. In vitro drug release of optimized formulation was found to be 94% after 90 min. The radio imaging study indicated localization of drug in the brain. Hence, tramadol HCl microspheres based on a HPMC E15 may be a promising nasal delivery system for CNS targeting.

The purpose of this study was to mask the intensely bitter taste of metoclopramide HCl and to formulate a rapid disintegrating tablet (RDT) of the taste-masked drug. Taste masking was done by complexing metoclopramide HCl with aminoalkyl methacrylate copolymer (Eudragit EPO) in different ratio by the extrusion-precipitation method. Drug-polymer complexes (DPCs) were tested for drug content, in vitro taste in simulated salivary fluid (SSF) of pH 6.8, taste evaluation in oral cavity and molecular property. The complex having drug-polymer ratio of 1 : 2 shows significant taste masking, confirmed by drug release in SSF and in-vivo taste evaluation; therefore, it was selected for further study. Taste evaluation of DPCs in human volunteers revealed considerable taste masking with the degree of bitterness below threshold value (0.5) within 10 s, whereas, metoclopramide HCl was rated intensely bitter with a score of +3 for 10 s. Tablets were evaluated for various parameters like tensile strength, wetting time, water absorption ratio, in-vitro disintegration time, and disintegration in oral cavity. The effect of diluents, lubricants and sweetening agent (Xylisorb) on the disintegration time was also evaluated. Tablets of batch F3 containing mannitol and microcrystalline cellulose in the ratio 1 : 1 and 8% w/w crosspovidone showed faster disintegration (within 20 s) than the marketed formulation (180 s). Good correlation between in vitro disintegration behavior and in the oral cavity was recognized. Tablets of batch F3 also revealed rapid drug release (t(90), 90 s) in SGF compared with marketed formulation (t(90), 600 s).

The aim of the present study was to prepare mucoadhesive multiparticulate system for oral drug delivery using ionic gelation technique. Microspheres composed of various mucoadhesive polymers including HPMC of various grades like K4M, K15M, K100M, E50LV, Carbopol of grades 971P, 974P and polycarbophil were prepared. In this technique cross linking of sodium alginate with calcium chloride was done which retarded the release of drug from the mucoadhesive polymer. In the present work Metoprolol tararate was used as a model drug. Interaction studies performed using FTIR spectroscopy revealed that there was no drug to polymer interactions. The preliminary mucoadhesive strength studies performed for various polymers using rotating cylindrical method showed that HPMC had greater mucoadhesive properties than carbopol and polycarbophil. Microspheres so prepared were discrete, bulky, free flowing and showed an average encapsulation efficiency ranging from 50-60%. Particle size of the microspheres, as determined by the optical microscopy was found to be between 400-650 microm. The prepared formulations also exhibited a good mucoadhesive strength which was determined in in vitro conditions through falling film technique and was compared with ex vivo studies. The microspheres so prepared also exhibited a good swelling index which confirmed the strong mucoadhesive property of the formulation. Metoprolol release from the multiparticulate system was regulated and extended until 12 hours and exhibited a non fickian drug release kinetics approaching to zero order, as evident from the release rate exponent values which varied between 0.57 to 0.73. The stability studies performed on the optimized batches at 40 degrees C /75% RH for 90 days indicated no significant change in the physicochemical properties.