Light formulation evaluation

The performance of AOS vs. the other surfactants was tested with three foam boosters, namely, amide oxide (AO), lauryl myristic monoethanol amide (LMMEA), and coco diethanolamide (coco DEA) at 90 10 anionic/booster ratio. Blends were evaluated at 0.025% active, 41 °C, and 140 ppm vegetable shortening oil. The results in Fig. 21 show that AOS blends outperform the reference standard whereas the other blends were of equal or less performance. The AOS/LMMEA blend gave superior performance. It was further shown that the addition of a small amount of AES (10% on total actives) further enhanced the performance of the AOS system (see Fig. 22). AOS when formulated with AES and amide therefore has outstanding dishwashing performance and is an attractive candidate for use in formulating light-duty liquids. 

The formulation to be tested at each site must be evaluated in the light of test substances with multiple formulation usages and geographical requirements. 

An initial use of reflectance spectroscopy in the characterization of pharmaceutical solids concerned studies of the stability of coloring agents in tablet formulations. With the description of a device that enabled the surface of intact tablets to be studied [14], the photostability of various dyes and lakes in tablets was followed [15,16]. Exposure of formulations to both normal and exaggerated light conditions was investigated, and the kinetics of the photodegradation evaluated. In most cases, the photoreactions appeared to follow first-order kinetics. 

The effect of particle size, and hence dispersion, on the coloring properties of aluminum lake dyes has been studied through quantitative measurement of color in compressed formulations [47], It was found that reduction in the particle size for the input lake material resulted in an increase in color strength, and that particles of submicron size contributed greatly to the observed effects. Analysis of the formulations using the parameters of the 1931 CIE system could only lead to a qualitative estimation of the effects, but use of the 1976 CIEL m v system provided a superior evaluation of the trends. With the latter system, the effects of dispersion on hue, chroma, lightness, and total color differences were quantitatively related to human visual perception. 

An easy way to evaluate the initiation rate, Y[ = Iq (1-e " 2,3 e l [pl]) Oj, and a possible deviation from its first-order dependence on the light intensity, is by monitoring the induction period (tj). Under air diffusion-free conditions (laminate), a given number of radicals (N) must be generated by photolysis of the initiator to consume the 02 molecules dissolved in the formulation, before polymerization can start ... 

The candidate method is used to support drug synthesis, excipient compatibility, and ultimately to evaluate candidate formulations. Such support typically involves analyses of stressed materials to identify degradation trends. These studies are conducted in the solid state by exposing the DS and DP to relative humidity, temperature, light, and oxidizing... 

In the light of these observations and the newer trends in product formulation, it was decided to study the in vitro release and permeation of propranolol hydrochloride from various hydrophilic polymeric matrices using the cellulose membrane and the hairless mouse skin as the diffusion barriers and to evaluate the effects of some of the additive ingredients known to enhance drug release from dermatological bases. 

In addition, a great need exists for improved test procedures to predict end-use performance. The correlations between accelerated exposure devices and normal fluorescent lamps, described in this report, represent only a preliminary effort to refine and establish meaningful laboratory methods for evaluating light stabilizers. Exposure data from a greater number of samples, containing a greater variety of formulations, are needed for more accurate correlations. 

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