[Effects of plasticizers and surfactants on the film forming properties of hydroxypropyl methylcellulose for the coating of diclofenac sodium tablets]

Hydroxy Propyl Methyl Cellulose [HPMC] 5cPs, an aqueous soluble polymer was employed for coating diclofenac sodium [DFS] tablets 25mg for protecting the integrity of the drug yet rendering the drug to release at a faster rate on contact with the gastric environment. Proper optimization for the aqueous based film coating formulation was undertaken primarily employing plasticizers like polyethylene glycol [PEG] 400 and propylene glycol [PG]. The defect free selected formulations were further subjected for studying the effects of surfactants like Sodium Lauryl Sulphate [SLS] and Tween-80 along with the plasticizers. The quality of the aqueous film coats or the plasticizer efficiency in case of PEG-400 is in the order 1.5%>0.5%>1.0% and for PG 1%> 4%> 3% which can be stated on the basis of less incidence of major coat defects like chipping, cracking, orange peel, roughness, blistering, blooming, picking. The quality of aqueous film coat or the surfactant efficiency in case of SLS+PEG-400 is in the order 0.3%< 0.5%< 0.1% and SLS+PG is in the order 0.5%< 0.1%< 0.3%. In case of Tween-80+PEG-400 the order is 0.3%< 0.5%< 0.1% and Tween-80+PG is in the order 0.3%< 0.1%< 0.5%. Elegant film formation can be stated from fewer incidences of coat defects. The obtained coated tablets eventually satisfied all the normal physical parameters like thickness, weights, and weight gain, drug content, crushing strength, percent friability, disintegration time, dissolution profile and possible drug-polymer interactions. ANOVA was undertaken followed by Dunnet multiple comparison for the dissolution profile considering uncoated as the standard. The difference was considered significant at p

Synthesis of NAD+ in erythrocytes incubated with nicotinic acid and the effect of di-(2-ethyl hexyl) phthalate (DEHP).

Synthesis of NAD+ from nicotinic acid by erythrocytes incubated in SAGM phosphate solution and effect of di-[2-ethyl hexyl] phthalate, a plasticizer commonly used in PVC blood/component storage bags, on this synthesis was studied. Erythrocytes are able to synthesise NAD+ in SAGM (sodium chloride, adenine, glucose, mannitol) phosphate solution and this synthesis was more in the presence of added nicotinic acid (optimum concentration 1 mM). The level of NAD+ decreased when the incubation period was increased from 24 to 48 hr. Glutamine had a deleterious effect on this synthesis, possibly due to the decrease in pH. Di-[2-ethyl hexyl] phthalate had an inhibitory effect on NAD+ synthesis when the cells were incubated in SAGM phosphate solution, either alone or in the presence of added nicotinic acid. There was significant decrease in the release of potassium and haemoglobin from the cells in the presence of nicotinic acid, indicating increased red cell stability.