Excipient starch derivatives used

Similar analyses of moisture uptake data available in the literature for other cellulose and starch derivatives used as pharmaceutical excipients are presented in Table 5. Considering the uncertainties associated with the estimated moisture uptake values from published graphs, the values of are all quite consistent with each other and with a stoichiometry of one water molecule per anhydroglucose unit. It is interesting to note that the two samples derived from cellulose, sodium carboxymethylcellulose and sodium croscar-mellose, did not require any correction for degree of crystallinity to conform to close to a 1 1 stoichiometry. It appears quite likely, therefore, that the change in chemical structure and the processing of these materials essentially eliminates the crystallinity of cellulose. 

Starch is one of the most commonly used excipients in the pharmaceutical industry due to its disintegration and binding properties. A number of sources of starch are commercially available, with corn starch being the most common. An overview of starches and starch derivatives and their use in the pharmaceutical industry is presented. 

Research on nasal powder drug delivery has employed polymers such as starch, dextrans, polyacrylic acid derivatives (e.g., carbopol, polycarbophil), cellulose derivatives (microcrystalline cellulose, semicrystalline cellulose, hydroxypropylmethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose), chitosan, sodium alginate, hyaluronans, and polyanhydrides such as poly(methyl vinyl ether-co-maleic anhydride) (PVM/MA). Many of these polymers have already been used as excipients in pharmaceutical formulations and are often referred to as first-generation bioadhesives [38-45], In nasal dry powder a single bioadhesive polymer or a... 

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