Capsules elastic

The lens is an avascular transparent tissue surrounded by an elastic, collagenous capsule. Disturbances in the normal metabolism of the lens and rupture of the lens alter its optical characteristics, and may cause cataract, i.e., reduced transparency of the lens. For example exposure to a herbicide, 2,4-dichlorophenol, may cause cataract. 

WR Ebert. Soft elastic gelatin capsules a unique dosage form. Pharm Tech 1(10) 44—50, 1977. 

S Vemuri. Measurement of soft elastic gelatin capsule firmness with a universal testing machine. Drug Dev Ind Pharm 10 409 424, 1984. 

Accommodation (fig. 9). The lens of the eye is suspended by the zonula (suspensory ligament) consisting of delicate transparent fibres attached on the one hand to the ciliary body and on the other to the elastic capsule covering the lens. At rest, this zonula is under tension and in consequence the lens assumes a flattened form. When the ciliary muscle contracts it pulls the... 

A new variation of interfacial polymerization was developed by Russell and Emrick in which functionalized nanoparticles or premade oligomers self-assemble at the interface of droplets, stabilizing them against coalescence. The functional groups are then crosslinked, forming permanent capsule shells around the droplets to make water-in-oil (Lin et al. 2003 Skaff et al. 2005) and oil-in-water (Breitenkamp and Emrick 2003 Glogowski et al. 2007) microcapsules with elastic membranes. 

Valproic acid is a carboxylic acid designated as 2-propyl-pentanoic acid. It is also known as dipropylacetic acid. Capsules and syrup are antiepileptics for oral administration. Each soft elastic capsule contains 250 mg valproic acid. 

Elastic elements such as diaphragms and capsules are used as sensing elements in combination with different displacement transducers (e.g. inductive, potentiometric, etc.) for low/medium vacuum measurements down to about 1 torr. Elastic elements have been employed in conjunction with capacitive transducers for the measurement of pressures as low as 10 5 torr. 

Ebert W.R. 1977. Soft elastic gelatin capsules A unique dosage Rtim/naceutical Technology, 1(10) 44. 

Rakucewicz J. 1986Soft Elastic Gelatin Capsule Manufacturing The Globex tWiyiematics Control Corp., Dear Park, New York. 

Shah N. H., D. Stiel, M. H. Infeld, A. S. Railkar, and M. Patrawala. 1992. Elasticity of soft gelatin capsules containing polyethylene glycol 400-quantitation and resoluIRtrarmaceutical Technology, 16 126. 

R. A. Kenley, S. Chandry, and G. A. Visor, Multidimensional column-switching liquid chromatographic method for dissolution testing of enprostil soft elastic gelatin capsules, J. Pharm. Sci., 75 999 (1986). 

A three-column ion-exchange and reversed-phase system has been developed for the assay of enprostil in soft elastic gelatin capsules [336]. A two-column approach has also been used to resolve D,L-amino acids in complex matrices [337]. Erythromycin A and its known impurities were resolved using two C18 columns [338]. 

Inorganic nanoparticles themselves can be assembled into mesoscopic structures. Dinsmore et al. proposed an approach for the fabrication of solid capsules from colloidal particles with precise control of size, permeability, mechanical strength, and compatibility (Fig. 2.9).44 This unusual mesoscopic structure is called colloidosome and is prepared through emulsion droplets at a water-oil interface. Following the locking together of the particles to form elastic shells, the emulsion droplets were transferred to a fresh continuous-phase fluid identical to that contained inside the droplets. The resultant structures are hollow, elastic shells whose permeability and elasticity can be precisely controlled. 

The mechanical properties of polyelectrolyte multilayer capsules have been subject of several studies using different methods. Baumler and co-workers [7] have used the micropipette technique and found that PMCs are not conserving their volume if pressure differences are applied between inside and outside of the shell. This is expected, since the shells can only be formed in first place because the membrane is permeable to low molecular weight species, the core dissolution products. They found no deformation up to a critical pressure followed by an irreversible collapse, showing that shells deform not elastically but plastically for large deformations. First quantitative estimates of the Young s modulus of the shell material were obtained by Gao and coworkers, using osmotic pressure differences between inside and outside of the shell [8,9], These authors monitored the onset of the buck-... 

This allows us to derive the elastic properties of the capsules from the measured shell spring constants. The most precise way to do so is to use the combination of the data in Fig. 3, since the slope of the rescaled data contains the Young s modulus of the material and is an average over all measurements. However, since the measurements were carried out in water and not in dried state, like the thickness measurements, the thickness has to be modified to account for the swelling of PAH/PSS. Kiigler et al. showed that the thickness of the multilayers depends on the degree of humidity [27]. According to their study, PAH/PSS multilayers swell by 15% between multilayers dried under ambient conditions and immersed into water. Similar results were found by Losche et al. [28], who... 

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