Saudi- corn starch as a tablet excipient compared with imported starch

A locally produced starch from Saudi cultivated corn was evaluated as a tablet excipient and compared with an imported corn starch that is produced internationally and used by a local leading pharmaceutical company. The comparative evaluation included: quality control, physical characterization, viscosity of starch paste, binding properties during granulation and disintegrating power when used in tablet preparation. Theophylline was used as a model drug. The two starches were subjected to evaluation after freeze and spray drying processes. Both starches showed similar particle sizes with poor flowability although the flow properties were in favor of the imported starch. Enhanced flowability was noticed in both starches upon freeze drying and spray drying. Granules prepared by wet granulation using the imported starch were less friable indicating good binding ability compared to the Saudi starch. Interestingly, tablets made from the Saudi starch disintegrated faster and released the drug faster than those made from the imported starch. Thus, it was concluded that although imported starch had more binding capacity than Saudi starch, yet Saudi starch has more disintegrating power and produced immediate drug releasing tablets. These findings may be considered for possible utilization of locally produced Saudi starch as a tablet excipient, in future

Evaluation of spray and freeze dried excipient bases containing disintegration accelerators for the formulation of metoclopramide orally disintegrating tablets

Orally disintegrating tablets [ODT] are gaining attractiveness over conventional tablets specially for patients having difficulty in swallowing such as pediatric, geriatric, bedridden and disable patients. ODT technologies render the tablets disintegrate in the mouth without chewing or additional water intake. So far there have been many patents for ODT, but only few publications are dealing with this dosage form. The aim of the present study was to formulate metoclopramide in ODT with sufficient mechanical strength and fast disintegration from bases prepared by both spray [SD] and freeze drying [FD] techniques. Different disintegration accelerators [DA] were utilized to prepare the proper ODT using various super-disintegrants [Ac-Di-Sol, Kollidon and sodium starch glycolate], a volatilizing solvent [ethanol] and an amino acid [glycine]. Metoclopramide, an antiemetic medication, was used as a model drug in the formulated ODT. It was noted that the disintegration of ODT depends on utilization of DA in both SD and FD techniques to prepare tablet bases for ODT and so many other factors such as drying process, type of DA, and the addition of DA before or after the drying processes. The good disintegration property of the prepared tablets was related to the excellent wettability of the ingredients after being subjected to the drying processes. Results also showed that the addition of DA to the tablet bases before drying process results in lengthening of the disintegration time in comparison to their addition to the tablet bases after the drying process. These findings could be utilized for many drugs and they may be considered versatile in the applications. Also, the disintegration of the ODT in the buccal cavity may favor fast absorption via the mucus membrane in the oral cavity

Spray-dried HPMC Microparticles of Indomethacin: impact of drug-polymer ratio and viscosity of the polymeric solution on dissolution

Polymeric microparticles prepared by spray-drying technique were investigated to enhance the dissolution rate of indomethacin [IM] in comparison with conventional microparticles prepared by co-precipitation solid dispersion method. Drug-polymer ratios and viscosity of polymeric solutions as potential factors were used in order to enhance the dissolution rate of IM. Spray-drying technique was used for preparing of microparticles using aqueous suspension of IM in hydroxypropyl methylcellulose [HPMC] polymer solution. The effect of drug-polymer ratios on dissolution rates of IM was studied in simulating intestinal medium. IM was analyzed spectrophotometrically at lambda=320 nm. For each drug-polymer ratios, low and high viscosity polymeric solutions were prepared and their impacts on the dissolution of IM were observed. Microparticles were morphologically characterized by optical microscopy. The interaction between IM and HPMC was studied by differential scanning calorimetry [DSC] and x-ray diffractometry [XRD]. Spherical fluffy microparticles of IM were obtained using HPMC. It was observed that the prepared spray-dried microparticles significantly increase the dissolution rate of IM. The increase in dissolution rates was achieved with drug: polymer ratios 1:1 as well as 1:2 and interestingly, the decrease in drug content in ratio exceeding 1:2 resulted in reduction in dissolution rates. Also, with all drug-polymer ratios, the low viscosity polymeric solutions gave the higher dissolution rates. In conclusion, HPMC microparticles loaded with IM were prepared by spray-drying technique and the potential of this technique to enhance the dissolution was studied. The findings indicate that the dissolution profile of IM microparticles prepared by spray-drying technique relied on drug-polymer ratios and viscosity of polymeric solutions