Water-soluble medications

Specific effluents Medical, water soluble machining oil, olive oil, photograph Detoxification... 

For mixture.s the picture is different. Unless the mixture is to be examined by MS/MS methods, usually it will be necessary to separate it into its individual components. This separation is most often done by gas or liquid chromatography. In the latter, small quantities of emerging mixture components dissolved in elution solvent would be laborious to deal with if each component had to be first isolated by evaporation of solvent before its introduction into the mass spectrometer. In such circumstances, the direct introduction, removal of solvent, and ionization provided by electrospray is a boon and puts LC/MS on a level with GC/MS for mixture analysis. Further, GC is normally concerned with volatile, relatively low-molecular-weight compounds and is of little or no use for the many polar, water soluble, high-molecular-mass substances such as the peptides, proteins, carbohydrates, nucleotides, and similar substances found in biological systems. LC/MS with an electrospray interface is frequently used in biochemical research and medical analysis. 

In concentrated NaOH, chitin becomes alkali chitin which reacts with 2-chloroethanol to yield 0-(2-hydroxyethyl) chitin, known as glycol chitin this compoimd was probably the first derivative to find practical use (as the recommended substrate for lysozyme). Alkali chitin with sodium monochloroacetate yields the widely used water-soluble 0-carboxymethyl chitin sodium salt [118]. The latter is also particularly susceptible to lysozyme, and its oUgomers are degraded by N-acetylglucosaminidase, thus it is convenient for medical appHcations, including bone regeneration. 

Amphotericin B is particularly effective against systemic infections caused by C. albicans and Cryptococcus neoformans. It is poorly absorbed from the gastrointestinal tract and is thus usually administered by intravenous injection under strict medical supervision. Amphotericin B methyl ester (Fig. 5.15C) is water-soluble, unlike amphotericin B itself, and can be administered intravenously as a solution. The two forms have equal antifungal activity but higher peak serum levels are obtained with the ester. Although the ester is claimed to be less toxic, neurological effects have been observed. An ascorbate salt has recently been described which is water-soluble, of similar activity and less toxic. 

FMC designs one such water-soluble coating for timed-release medications — Aquacoat ECD, a 30% by weight aqueous dispersion of ethylcellulose. This polymer is used to coat drug-layered beads that are delivered using gelatin capsules... 

Ointments are semisolid preparations that are intended for external use. Ointments may contain either finely powdered drugs or their mixtures, liquids, and other drug forms incorporated into appropriate bases. They are applied to the skin for their physical effects as emollients (which make the skin more pliable), protectants, lubricants, and drying agents. Ointment bases are also used as vehicles in which to incorporate topical medications which exert specific effect. There are four types of ointment bases, namely, oleaginous, absorption, water removable, and water soluble bases. 

Polyvinyl alcohol (PVA), which is a water soluble polyhidroxy polymer, is one of the widely used synthetic polymers for a variety of medical applications [197] because of easy preparation, excellent chemical resistance, and physical properties. [198] But it has poor stability in water because of its highly hydrophilic character. Therefore, to overcome this problem PVA should be insolubilized by copolymerization [43], grafting [199], crosslinking [200], and blending [201], These processes may lead a decrease in the hydrophilic character of PVA. Because of this reason these processes should be carried out in the presence of hydrophilic polymers. Polyfyinyl pyrrolidone), PVP, is one of the hydrophilic, biocompatible polymer and it is used in many biomedical applications [202] and separation processes to increase the hydrophilic character of the blended polymeric materials [203,204], An important factor in the development of new materials based on polymeric blends is the miscibility between the polymers in the mixture, because the degree of miscibility is directly related to the final properties of polymeric blends [205],... 

Some of the properties of polymers derived from (NPC12)W and alanine152 and from arylamines153 have been described. The former are water-soluble and have potential medical applications. Molar refraction and volume data on NP(NHC6-H4R-p)2n (R = H, Me, OMe, or Cl) have been determined.154... 

Coloring is not always necessary, but may be of value in certain medications. For example, oral liquids are generally eolored using a dye to match the flavor of the medication. Pharmacists must be aware of the different oil, alcohol, and water solubilities of the dyes they use. 

Creams are opaque, soft solids or thick liquids intended for external application. Creams may contain medications dissolved or suspended in water-soluble or vanishing cream bases and can be either water-in-oil or oil-in-water. An example is given below. 

Liver Chemical Processing. For protection from dangerous accumulation of various toxins, the body has evolved methods to eliminate foreign substances. Potentially harmful chemicals can originate from myriad sources including foods, liquids, air, and, of course, medications. The liver s role is to inactivate these chemicals and to convert (metabolize) them to water-soluble forms (i.e., forms that dissolve in water rather than fat), which can more easily be filtered and eliminated by the kidneys. 

Kidneys Chennical Disposal. The kidneys are the body s filter system. In order to be filtered by the kidneys, a molecule must be relatively small and water soluble. Most psychiatric medications fulfill neither of these requirements. However, after successive metabolic steps that are primarily completed in the liver, the molecules are smaller and/or water soluble so that the kidneys can more readily clear them. 

Since the discovery of synthetic dye by Perkin and the establishment of the synthetic organic chemistry industry, a wide variety of synthetic dyes provided a set of choices for staining microbes so that they could be readily examined under the microscope. It is reasonable to suppose that if a dye binds selectively to a microbe much more than to mammalian tissues, then it may be possible to find a dye that selectively harms the microbe and spares the mammal. Paul Ehrlich (figure 1.6) was a medical student who did research in the distribuhon of foreign substances in the body, and he was particularly interested in the influence of chemical structures of different types of molecule in live animals. He observed that acidic dyes with the sulfonic acid function, used by dye manufacturers to enhance water solubility, were unable to penetrate into the brain or fat tissues. 

Measurements of the amount of nickel in your blood, feces, and urine can be used to estimate your exposure to nickel. More nickel was found in the urine of workers who were exposed to nickel compounds that dissolve easily in water (soluble) than in the urine of workers exposed to compounds that are hard to dissolve (less-soluble). This means that it is easier to tell if you have been exposed to soluble compounds than less-soluble compounds. The nickel measurements do not accurately predict potential health effects from exposure to nickel. More information on medical tests can be found in Chapters 2 and 6. 

Diazepam, lorazepam, and midazolam are used for preanesthetic medication and as adjuvants during surgical procedures performed under local anesthesia. As a result of their sedative, anxiolytic, and amnestic properties, and their ability to control acute agitation, these compounds are considered to be the drugs of choice for premedication. (The basic pharmacology of benzodiazepines is discussed in Chapter 22.) Diazepam and lorazepam are not water-soluble, and their intravenous use necessitates nonaqueous vehicles, which cause pain and local irritation. Midazolam is water-soluble and is the benzodiazepine of choice for parenteral administration. It is important that the drug becomes lipid-soluble at physiologic pH and can readily cross the blood-brain barrier to produce its central effects. 

Norfloxacin is a new water-soluble fluoroquinolone registered for veterinary use in several countries. It is commercially available as a dry powder for medication of drinking water and as a sterile injectable solution (182). 

---