THE HEN'S EGG TEST - CHORIO-ALLANTOIC-MEMBRANE (HET -CAM) AND HAEMOLYSIS STUDY AS AN ALTERNATIVE TEST FOR OCCULAR IRRITANCY ANIMAL EXPERIMENTS (Draize Test)

Human eyes are frequently exposed to chemicals accidentally or on purpose due to their external location. Therefore, chemicals are required to undergo the evaluation of the ocular irritancy for their safe handling and use before release into the market. Draize rabbit eye test developed in 1944, has been a gold standard test which was enlisted as OECD TG 404 and OECD TG 405 but it has been criticized with respect to animal welfare due to invasive and cruel procedure. To replace it, diverse alternatives have been developed: (i) Hen Egg Test-Chorio-Allantoic-Membrane (HET-CAM) test (ii) RBC Haemolysis study

Design and development of controlled porosity osmotic tablet of diltiazem hydrochloride.

The present work aims towards the design and development of extended release formulation of freely water-soluble drug diltiazem hydrochloride (DLTZ) based on osmotic technology by using controlled porosity approach. DLTZ is an ideal candidate for a zero-order drug delivery system because it is freely water-soluble and has a short half-life (2-3 h). Sodium chloride (Osmogen) was added to the core tablet to alter the solubility of DLTZ in an aqueous medium. Cellulose acetate (CA) and sorbitol were used as semipermeable membrane and pore former, respectively. The effect of different formulation variables namely concentration of osmogen in the core tablet, % pore former, % weight gain, pH of the dissolution medium and agitation intensity on the in vitro release was studied. DLTZ release was directly proportional to % pore former and inversely proportional to % weight gain. The optimized formulation (F8) delivered DLTZ independent of pH and agitation intensity for 12 h at the upper level concentration of % pore former (25% w/w) and middle level concentration of % weight gain (6% w/w). The comparative study of elementary osmotic pump (EOP) and controlled porosity osmotic pump revealed that it superior than conventional EOP and also easier and cost effective to formulate