Current Drug Therapy - Volume 9, Issue 2, 2014

Diluents, also known as fillers, are used to make up the required bulk when the drug dosage is inadequate to produce the bulk of the tablet. In the present study the effect of diluents such as Lactose, Starch and microcrystalline cellulose on the evaluation parameters of curcumin-Hydroxyl Propyl β Cyclodextrin (HPβCD) bioadhesive vaginal tablets containing Carbopol 934P, Hydroxy propyl methyl cellulose (HPMC) and Hydroxy ethyl cellulose (HEC) as bioadhesive polymers was investigated. Curcumin tablets were prepared by direct compression method and evaluated for average thickness, hardness, friability, drug content, % swelling, drug release and mucoadhesion. The FT-IR and DSC spectra revealed that there was no chemical interaction between curcumin HPβCD and diluents used. The release was observed to follow both first order kinetics and fickian diffusion. The results obtained suggest that the diluents used have significant effect on % swelling, in vitro release and mucoadhesion. From the study it was observed that using lactose or microcrystalline cellulose in the formulations resulted in faster drug release profiles when compare to starch. And lactose is the best suitable diluent for curcumin-HPβCD bioadhesive vaginal tablets.

Purpose: The objective of the present work was to develop a site specific gastro-retentive floating tablet of Troxipide for the treatment of peptic ulcer. Troxipide is a novel anti-ulcer agent having an elimination half-life of 7.4 hrs and mainly absorbed from the gastrointestinal tract. Methods: 32 factorial design was applied. Dependant variables were swelling index, hardness and % drug release. Pluronic acid F127 and HPMC K 15M were used as rate controlled polymer. Optimized formulations were evaluated for physical characteristics, buoyancy, buoyancy lag-time, drug content, in- vitro drug release, floating behavior and in-vivo X-ray study. Results: Formulation H5 (20% Pluronic acid F127 and 78% HPMC K 15M) showed a floating lag time 60 ±2 sec with a desired controlled release profile over a period of 10 hrs. FTIR and DSC studies confirmed no chemical interactions. In-vivo X-ray study for optimized formulations showed gastro retention for 6 hrs. Conclusion: Results demonstrate feasibility of development of gastroretentive floating tablet of Troxipide.

The present work aimed to develop and study the effect of HPMC on compression-coated floating - pulsatile delivery of Bisoprolol. Inner core tablet contains bisoprolol and a super disintegrant. Outer shell contains HPMC K4M and HPMC K100M as erodible layer along with a gas generating agent. Compression-coated tablet of bisoprolol with 120mg HPMC K4M (B2) showed a lag time of 3.40±0.1 hrs with 99.81% drug release. Whereas 110mg HPMC K100M (B5) showed a lag period 4.0±0.1 hrs with 98.91% drug release. A 32 factorial design was applied. HPMC K4M CR and K100M were independent variables whereas drug release, lag time at 4 hrs and swelling index were dependent variables. To understand the interaction of independent variables on dependent variables three dimensional surface response plots were drawn. The responses exhibited by batch F4 (55 mg HPMC K4M and 65 mg K100M) showed lag time 4.20 hrs following the sigmoidal release pattern. Optimized batch F4 gave good in-vitro in -vivo correlation.

Contrast induced nephropathy (CIN) is an iatrogenic form of acute kidney injury (AKI) with variable but growing prevalence secondary to increased need for contrast administration during medical investigations such as coronary angiography. The mechanism of CIN is complex and poorly understood but is believed to be secondary to renal medullary hypoxia secondary to direct tubular toxicity from the contrast media and vasoconstriction. N-acetylcysteine (NAC) an antioxidant and vasodilator, has shown promising results in early investigations but failed to demonstrate consistent results in subsequent clinical trials and their meta-analysis. In this review we aim to discuss pharmacological properties of NAC and appraise the literature regarding the use of NAC for the prevention of CIN after coronary angiography.

Acetylcholinesterase inhibitors are regarded as the most promising approach to treat Alzheimer’s disease (AD). However, their anticipated side effects limit their usage. Present investigations involved the incorporation of the newly synthesized 2-naphthol derivatives (PP-81 and PP-84) into solid lipid nanoparticles (SLNs) to improve their accessibility to the brain and enhance the levels of acetylcholine. Drug loaded SLNs of PP-81 and PP-84 showed that average particle size of 138 nm and 186 nm, positive zeta potential and total drug content of 86.13 ± 0.49 % w/v and 81.18 ± 0.78 % w/v respectively were obtained using microemulsification technique. The particles were found to be spherical in shape, with high drug entrapment (91.28 ± 0.14 % w/w, PP-81 and 70.94 ± 0.59 % w/w, PP-84) at 10 % drug loading. Confirmation of SLNs formation was performed using DSC and PXRD studies. In in vitro release study diffusion phenomenon was predominant and was prolonged up to 24 h. Elevated plus maze test was carried out to evaluate memory acquisition and retention; post treatment with SLNs and respective free drugs in scopolamine induced spatial memory deficit in mice. Results indicated a significant increase (p < 0.05) in percentage retention of memory and learning with PP-81 and PP- 84 SLNs respectively at 20 mg/kg. It can be an optimized potential therapeutic and brain targeting approach for the treatment of AD.

Cyclodextrins (CDs) offer a potential solution to delivery of hydrophobic drugs. Cyclodextrins are capable of hydrophobic drug binding due to their unique property of possessing a hydrophobic interior cavity and a hydrophilic exterior. When hydrophobic drugs are complexed with CD molecules a significant increase has been reported in the bioavailability of those drugs in free solution. The unique characteristics of cyclodextrins facilitate in development of a hydrogel for delivering drugs with varying degree of aqueous solubility. Further, the mechanical and chemical properties of hydrogels can act as an excellent system in delivery of hydrophobic drugs through their gel matrix.