FORMULATION AND OPTIMIZATION OF RITONAVIR NASAL NANOSUSPENSION FOR BRAIN TARGETING

Nowadays, HIV associated neurological disorder especially HIV-1 virus infection is enhanced. Current available HIV therapies only reduce the plasma viral level and do not kill the virus completely. Administered dosage form does not reach the central nervous system (CNS) completely by the conventional approach. The oral route of drug administration,causes gastrointestinal irritation, hepatic metabolism and slow onset of action and some methods are invasive, resulting in the patient's non compliance. To overcome these problems, an effective novel formulation that will directly reach the CNS or brain needs to be developed.This study aims to formulate intranasal nanosuspension of ritonavir. Ritonavir is widely used as an antiretroviral agent and it is a protease enzyme inhibitor which is poorly soluble in water. High pressure homogenization technique was used for preparation prepare and optimization of nanosuspension by using 2 factors 3 level full factorial design, which is further characterized for particle size, polydispersity index, zeta potential, pH, drug content, in vitro drug diffusion and ex vivo permeation study. For stability of nanosuspension, lyophilization of optimized formulation was done. A comparison study between plain drug, nanosuspension and the lyophilized formulation was carried out, and it showed a significant increase in drug release from the membrane.

Optimization and Evaluation of Self-nanoemulsifying Drug Delivery System for Enhanced Bioavailability of Plumbagin

Plumbagin, a potential bioactive lipophilic molecule, possesses limited solubility and low oral bioavailability. The purpose of the present study was to examine the potential of the self-nanoemulsifying drug delivery system for improving solubility and oral bioavailability of plumbagin. The self-nanoemulsifying drug delivery system was formulated from Capmul MCM (oil), Tween 20 (surfactant), and propylene glycol (cosurfactant). Central composite design was employed as statistical tool to optimize the formulation variables, X1 (oil) and X2 (surfactant: co-surfactant mixture ratio), of the self-nanoemulsifying drug delivery system. The responses studied were droplet size, self-emulsification time, % of drug release in 15 min, and equilibrium solubility. The optimized liquid self-nanoemulsifying drug delivery system was adsorbed on Neusilin US2 and characterized for flow properties, X-ray diffractometry, differential scanning calorimetry, in vitro dissolution, in vivo anti-inflammatory activity, and bioavailability study in Wistar rats, as well as ex vivo permeation study. The droplet size, polydispersity index, self-emulsification time, and equilibrium solubility of the optimized formulation were 58.500 ± 1.170 nm, 0.228 ± 0.012, 17.660 ± 1.520 s, and 34.180 ± 1.380 mg/mL, respectively. Its zeta potential, transmittance value, and cloud point were − 28.200 ± 1.200 mV, 99.200% ± 0.600, and 90 °C, respectively. Drug release was found to be 93.320% ± 1.090. In vivo anti-inflammatory study confirmed more enhanced activity from the self-nanoemulsifying drug delivery system than with pure plumbagin. Pharmacokinetic study in rats revealed that solid self-nanoemulsifying drug delivery system had 4.49-fold higher bioavailability than pure plumbagin. Ex vivo permeation study demonstrated 1.75-fold increased intestinal permeability of the self-nanoemulsifying drug delivery system than pure plumbagin. The developed self-nanoemulsifying drug delivery system is a useful solid platform for improving solubility and oral bioavailability of plumbagin.

Two-Step Optimization to Develop a Transdermal Film Loaded With Dapoxetine Nanoparticles: A Promising Technique to Improve Drug Skin Permeation

Dapoxetine (DPX) is an orally administered drug for the treatment of premature ejaculation (PE). One of the challenges of administering DPX orally as a tablet is its poor bioavailability (ie, 42%) due to extensive first-pass metabolism. Thus, it is vital to develop a new formulation and mode of delivery to achieve the unmet needs of PE treatment. In this study, an optimized DPX polymeric nanoparticle (PNP) was developed and subsequently loaded into a transdermal film. The Box–Behnken design was utilized to optimize 3 formulation factors affecting the particle size and entrapment efficiency (EE) of chitosan (CS)-alginate (ALG) PNPs. A 3-level factorial design was used to study the effect of 2 variables affecting DPX cumulative percent released and percent elongation from transdermal films loaded with DPX-PNPs. Permeation parameters were calculated following ex vivo permeation study through rat skin. Transport of the PNPs across the skin layers was investigated using a fluorescence laser microscope. Results revealed that an optimized PNPs formulation was developed with a particle size 415.94 nm and EE 37.31%. Dapoxetine was successfully entrapped in the polymeric matrix. Chitosan and ALG interacted electrostatically with the studied cross-linking agents to form a polyelectrolyte complex. The ex vivo study illustrated a sustained release profile of DPX with enhanced skin permeation from the film loaded PNPs. Moreover, the PNPs was able to penetrate deeper into skin layers. Therefore, DPX transdermal film developed in this work could be considered as a successful drug delivery with better patient compliance for the treatment of PE.

Non-invasive drug delivery system for the delivery of protein/peptide using neem gum and its derivatives

The present investigation is continuation of author’s previous work. In previous work, the author was prepared acrylamide grafted copolymer of neem gum and carboxymethylatedneem gum derivatives. Neem gum polysaccharide (NGP) and its derivatives viz. acrylamide grafted neem gum (NGP-g-Am) and carboxymethylated neem gum (CMNGP) were explored as film forming agent for transdermal delivery of protein/peptide drug (albumin). It was observed that films were not prepared at all the concentrations of NGP with a given concentration range. Studies show that film cannot be prepared using CMNGP even at ahigher concentration of polymer (2 % w/v solution). So only acrylamide grafted neem gum based film were prepared and evaluated. Transdermal films were prepared by using solvent casting method. The developed films were evaluated for various parameters such as drug content, folding endurance, thickness, weight variation, surface pH, moisture uptake, in vitro drug release study and ex-vivo permeation study. The films showed more than 300 folding endurance which demonstrated the good mechanical strength of film. It was also observed that after permeation studies small cracks were also formed in the films. Fabricated films were able to deliver drug upto 7 h. Drug release study and drug permeation studies showed that formulations followed zero order and KorsmeyerPepass model of kinetics. It can be concluded from the findings of the results that acrylamide graft copolymers of neem gum were able to deliver protein/peptide drugs through transdermal route.

Formulation and Evaluation of Sustained Release Sumatriptan Mucoadhesive Intranasal in-Situ Gel

Objective: The purpose of this study to develop and optimize nasal mucoadhesive in situ gel IG of sumatriptan ST (serotonin agonist) to enhance nasal residence time for migraine management. Method: Cold method was used to prepare ST nasal in-situ gel, using thermosensitive polymers (poloxamer 407 and/or poloxamer 188) with a mucoadhesive polymer (hyaluronic acid HA) which were examined for gelation temperature and gelation time, pH, drug content, gel strength, spreadability, mucoadhesive force determination, viscosity, in-vitro drug release, and the selected formula was subjected to ex-vivo permeation study and histological evaluation of the sheep mucosal tissue after application. Results: The results showed that the formula IG7 prepared from poloxamer 407(19%), poloxamer188 (4%) and HA (0.5%) had an optimum gelation temperature (32.66±1.52°C), gel strength (43.66± 1.52 sec), mucoadhesive force (8067.93± 746.45dyne\cm2), in-vitro drug release (95.98%) over 6hr, ex-vivo permeation study release (89.6%) during the 6 h. study with no histological or pathological change in the nasal sheep tissue. Conclusion: The ease of administration via a nasal drop of ST coupled with less frequent administration and prolong drug release, will enhance patient compliance.

Formulation and Evaluation of Tacrolimus Transdermal Gel

The present investigation is concerned with formulation and evaluation of Transdermal gels of Tacrolimus, anti-psoriasis drug, to circumvent the first pass effect and to improve its bioavailability with reduction in dosing frequency and dose related side effects. Twelve formulations were developed with varying concentrations of polymers like Carbopol 934P, HPMCK4M and Sodium CMC. The gels were tested for clarity, Homogeneity, Spreadability, Extrudability, Viscosity, surface pH, drug Content uniformity, in-vitro drug diffusion study and ex-vivo permeation study using rat abdominal skin. FTIR studies showed no evidence on interactions between drug, polymers and excipients. The best in-vitro drug release profile was achieved with the formulation F4 containing 0.5 mg of exhibited 6 hr drug release i.e. 98.68 % with desired therapeutic concentration which contains the drug and Carbopol 934p in the ratio of 1:2. The surface pH, drug content and viscosity of the formulation F4 was found to be 6.27, 101.3% and 3, 10,000cps respectively. The drug permeation from formulation F4 was slow and steady and 0.89gm of tacrolimus could permeate through the rat abdominal skin membrane with a flux of 0.071 gm hr-1 cm-2. The in-vitro release kinetics studies reveal that all formulations fit well with zero order kinetics followed by non-Fickian diffusion mechanism. Keywords: Transdermal gel, Viscosity, In-vitro drug release, In-vitro drug release kinetics study, Ex-vivo permeation study

Transdermal Delivery of Ondansetron HCl from Thermoreversible Gel Containing Nanocomposite

Background: Application of thermoreversible gel can be a solution to the low residence time of the topical dosage forms such as normal gel, ointment and cream on the skin surface. Addition of another polymer and a nanocomposite can improve the poor mechanical strength and fast drug release of poloxamer 407 (POL 407) gel. Therefore, it is essential to add xanthan gum (XG) and graphene oxide (GO, thickness 1-2 nm, lateral dimension 1-5 µm) to POL 407 gel to enhance the mechanical strength and to sustain the drug release from the gel. Methods: Thermal gel of ondansetron hydrochloride (OSH) containing nanocomposite was prepared by adopting cold method. Interaction between drug and polymers was studied using FTIR method, morphological investigation was carried out by optical and scanning electron microscopy method, and rheological study was performed employing rotational rheometer equipped with a cone/plate shear apparatus, gelation temperature by glass bottle method and ex vivo permeation study was performed with cylindrical glass diffusion cell. Skin irritation potential was measured using rat as a model animal. Results: The FTIR spectrum of the selected gel showed that there is shifting of O-H stretching vibration of a hydroxyl group from 3408.72 to 3360.49 cm-1 and appearance of a new band at 1083.01 cm-1. The spectrum of the selected gel also showed the absence of characteristic peaks of GO at 1625.49 cm- 1. This result indicated that there may be an interaction between OSH and GO and hydrogen bonding between XG and POL 407. The gelation temperature was found to be decreased with the increase in GO content from 14.1±1.21°C 13±0.97°C. SEM micrograph demonstrated the uniform dispersion and intercalation of GO sheets in the gel. All the gel formulations showed a pseudo-plastic flow. Ex vivo permeation study (for 24 hr) exhibited highest (6991.425 µg) and lowest (2133.262 µg) amount of drug release, for OG1 and OG5, respectively. This is attributed to an increase in viscosity which led to a decrease in drug permeation across the abdominal skin of rats. The OG1 formulation (without GO) showed the highest flux of 76.66 µg/cm2/h, permeability coefficient (Kp) of 5.111× 10-3 cm/h and enhancement ratio of 3.277 compared to OG5 containing highest amount (9% w/w) of GO. The selected gel was found to be physically stable and there was minimum irritation score. Conclusion: All the above results indicated that thermal gel containing nanocomposite sustained the drug release and can be considered as an alternative to the orally administered tablet of OSH.

FORMULATION AND EVALUATION OF LORAZEPAM ENCAPSULATED COLLAGEN/PECTIN BUCCAL PATCH

Objective: To formulate and characterize Lorazepam loaded buccal patches using mucoadhesive, biodegradable, natural polymers-pectin (hydrophilic) and collagen (lipophilic) for treating epileptic seizures. Methods: Lorazepam loaded buccal patches were prepared by solvent casting method and were subjected to various Physico-chemical evaluation parameters to find the optimized buccal patch. The in vitro drug release study and ex vivo permeation study was carried out. The stability study and histopathological study of optimized Lorazepam loaded buccal patch was also carried out. Results: From in vitro drug release study, it was found that Lorazepam loaded buccal patch (B4) exhibited maximum drug release of 96.16 %±0.07 than other formulations at the end of 4 h, indicating an initial burst release followed by sustained release with release kinetics as Higuchi diffusion model. Based on the in vitro drug release, % drug content, % swelling index, folding endurance, B4 formulation was considered as optimised formulation and was further characterized. Ex vivo permeation study revealed that the cumulative amount of drug permeated from optimised Lorazepam loaded buccal patch (B4) was higher (3831.4±0.21µg/cm2) than marketed Midazolam buccal solution (1724±0.12 µg/cm2) and control drug solution (895.42±0.07 µg/cm2) with an enhancement ratio of 4.8. B4 formulation also showed a higher flux value (12.52±0.02µg/cm2/hr) compared to marketed formulation (5.732±0.01 µg/cm2) and control drug solution (2.563±0.03 µg/cm2) of P<0.05. The histopathological study using bovine buccal mucosa revealed that the B4 formulation is safe for buccal application. The stability study confirmed that B4 formulation is stable in both room and refrigeration conditions. Hence the formulated Lorazepam loaded buccal patch seems to be a promising carrier for the enhanced buccal delivery of Lorazepam in treating epileptic seizures. Conclusion: The formulated Lorazepam loaded collagen/pectin buccal patch was found to be an efficient and stable route for the buccal delivery of Lorazepam in treating acute epileptic seizures which could be further explored scientifically.