Volume 2, Issue 3, Jul-Sep 2010

Volume 2

July-September 2010

Solid lipid nanoparticles: Potential applications

J S Mulla, I M Khazi, V G Jamakandi

Abstract:
In the middle of the 1990s, the attention of different research groups has focused on alternative nanoparticles made from solid lipids by name solid lipid nanoparticles (SLN or lipospheres or nanospheres). The SLN combine the advantages (e.g. physical stability, protection of incorporated labile drugs from degradation, controlled release, excellent tolerability) of other traditional colloidal systems, such as emulsions, liposomes and polymeric microparticles and nanoparticles; while at the same time minimizing the associated problems. SLN formulations for various application routes (parenteral, oral, dermal, ocular, pulmonar, rectal) have been developed and thoroughly characterized in vitro and in vivo. Recently, solid lipid nanoparticles (SLN) have been widely studied as a next-generation delivery system in pharmaceuticals and cosmetics. This paper reviews the applications of lipid based carrier systems, SLN.

Keywords: Solid Lipid Nanoparticles, Administration Routes, Controlled Release, Targeted Drug Delivery.

A comparative study: Solution stability and dissolution behavior of solid dispersions curcumin

Vedamurthy Joshi, Mohammed Gulzar Ahmed, Sarasija Suresh, Rajesh Kowti

Abstract:
Curcumin (CU), a yellow pigment obtained from Curcuma longa shows profound biological activities. Literature reveals that CU is insoluble in water and susceptible to higher pH. This work is focused firstly to study the susceptibility of curcumin in water, various pH conditions in presence and absence of ascorbic acid (AA), tartaric acid (TA) and citric acid (CA) by a simple UV absorption method and secondly to prepare and evaluate curcumin solid dispersions (CSD) by physical mixtures, hot melt method and solvent evaporation method using PEG-4000, PEG-6000 and PVP K-30 as carriers. Drug, carrier ratio for physical mixtures and hot melt method was 1:1, 1:4 and 1:8; drug, carrier and adsorbent (micro crystalline cellulose) ratio in solvent evaporation method was 1:1:2. Selected formulations with better solubility were studied for TLC, FTIR, SEM, X-ray diffraction studies, in vitro release and in vitro absorption studies using everted rat gut technique. Results indicated that the CU and CSD were unstable in solution; the stability was more in acidic pH and decrease as the pH increases. Presence of AA, TA and CA in solution enhanced the CU aqueous stability relatively by 3 folds in pH 7.4 however more degradation was observed in CSD solutions in pH 7.4 even in presence of these acids. Hot melts of drug with PEG 6000 in 1:8 ratio showed maximum solubility of 1mg/ml than that of other CSDs. Maximum in vitro release was observed by hot melts than that of other CSDs. Hot melts showed burst release in 10 min followed by the degradation of curcumin in aqueous solution indicating occurrence of rapid hydrolytic reaction. In vitro absorption of hot melts and pure curcumin in rat gut was insignificant as the permeability of both were negligible.

Keywords: Curcumin, Solution, Stability, Solid Dispersions, In-vitro Release.

Formulation and dissolution studies of solid dispersions of nifedipine

K Nagarajan, M Gopal Rao, Satyajit Dutta, R Pavithra, G Swetha

Abstract:
Nifedipine is a water insoluble antianginal drug and its dissolution rate from solid dispersion was affected largely by the carrier concentration. The common solvent evaporation method and melting fusion method were used for the preparation of solid dispersion in different ratios (9:1, 3:1, 1:1, 1:3, 1:9) using polyethyleneglycol (PEG 4000) to enhance the solubility of drugs. The interaction between drug and carrier were characterized by TLC and IR spectroscopic studies. The Rf value of prepared dispersion was similar to that of the pure drug (0.18) in UV 254 nm light. No extra spots were detected which indicated that there was no interaction between the drug and carrier. In addition, the IR result of the prepared dispersions showed no interactions between the drug and carrier. Hence the prepared solid dispersions improved the dissolution characteristics of Nifedipine as evidenced from the reported results.

Keywords: Nifedipine, Polyethyleneglycol, Antianginal, Tolbutamide.

Physicochemical characterization of Acacia sieberiania gum

A R Oyi, A O Shittu, H S Mahmud

Abstract:
Acacia sieberiana gum obtained from Jigawa forestry, Dutse – Nigeria, was purified and investigated for its physicochemical properties such as particle size distribution, bulk and tapped densities, angle of repose, flow rate, Carr’s index, swelling capacity, apparent viscosity, pH effects on viscosity, hydration capacity, moisture content and chromatographic analysis. Using standard and official methods, studies revealed that the gum possessed adequate properties to make it fit for use as an excipient in the formulation of solid, liquid dosages and for modified release formulations.

Keywords: Polymeric Material, Physicochemical Properties, Excipients.

Development and characterization of nasal mucoadhesive microemulsion of sumatriptan succinate

Ashwini Rasal, H S Mahajan, H T Shaikh, S J Surana

Abstract:
The purpose of this study was to enhance the brain uptake of sumatriptan succinate (SS) in o/w microemulsion, which was suitable for intranasal delivery. Microemulsion system with Tween 80, Span 80 as surfactants and n-butanol as cosolvent and iso propyl myristate as oil was developed for intranasal delivery of sumatriptan succinate. Single isotropic region, which is considered as o/w microemulsion was found in the pseudo-ternary phase diagrams developed at various tween 80, span 80 and n butanol ratios. The optimal microemulsion formulation consisted of 5% iso propyl myristate, 25% water, and 70% (w/w) surfactant/cosurfactant [surfactants are 52.5% (tween 80 36.75% span 80 15.75%) cosurfactant (n butanol) 17.5% at 3: 1 weight ratio] With the increase of tween 80 concentration, the microemulsion region area, microemulsion viscosity, and the amount of water into the microemulsion system increased. Mucoadhesive microemulsion was prepared by using HPMCK4M as a mucoadhesive polymer to increase the residence time inside the nasal cavity for prolonged action and direct targeting release of drug to the brain. Nasal absorption of sumatriptan succinate from this mucoadhesive microemulsion was found to be fairly rapid, as it converts into gel inside the nasal cavity and increase the residence time and could improve bioavailability of the drug. The result suggests that this mucoadhesive microemulsion may be a useful approach for the rapid onset delivery of sumatriptan succinate during the emergency treatment of acute attack of migraine.

Keywords: Microemulsion, Nasal Delivery, Mucoadhesion, Sumatriptan Succinate.

Formulation and evaluation of controlled release matrix tablet with solid dispersion granules of aceclofenac

D V Pawar, Md Sarfaraz, P Yerole

Abstract:
The goal of this study is to develop once daily controlled release matrix tablet of aceclofenac by applying solid dispersion technique for improving solubility. The matrix tablets of aceclofenac solid dispersion granules were prepared by direct compression method using selected hydrophilic polymers like hydroxylmethyl cellulose (HPMC) and Carbopol 934(CP). Preformulation and micromeritic studies were carried out. The matrix tablets were evaluated for their physicochemical properties, in vitro drug release and stability studies. Formulation containing 25% HPMC (F1) has complete release of 24 hrs as well as CP containing formulations showed concentration dependent rate of drug release. To achieve complete drug release, solid dispersion of aceclofenac was prepared using mannitol and dicalcium phosphate (DCP). Dissolution profile of matrix tablet containing solid dispersion with mannitol/ DCP has shown increase in the release rate compared to matrix tablets alone. Solid dispersion using mannitol was found effective with matrix tablets of CP as compared to matrix tablet of HPMC. From this study, it was clarified that solid dispersion granules was one of the promising controlled release system applying solid dispersion technique for the poorly water soluble drug.

Keywords: Matrix Tablet, Controlled Release, Aceclofenac, Hydrophilic Polymers, Direct Compression, In Vitro Release.

Indian Journal of

Novel Drug Delivery ISSN 0975-5500

Indian Journal of Novel Drug Delivery ISSN 0975-5500