Antiseptic methods

Louis Pasteur (1822-1895) established that some diseases are caused by microorganisms and not, as was thought to be the case at the time, by miasmas, evil spirits or divine intervention. Despite the scepticism of physicians, as illustrated above, Pasteur s work inspired a British surgeon, Joseph Lister, to introduce antiseptic methods into surgery in order to prevent wound infection. In March 1865, he operated for the first time using an antiseptic, carbolic acid (phenol). There were no infections after the surgery - a rare occurrence at that time. 

Several methods have received considerable research attention as alternatives to salt curing. These include use of sodium bisulfite as a disinfectant to allow preservation with or without decreased salt in a brine cure use of disinfectants such as quatenary amines for temporary preservation in direct shipping to the taimery from the packing plant (see Disinfectants and antiseptics) preservation of hides by radiation sterilization (see Sterilization techniques) and substitution of materials such as potassium chloride for sodium chloride. These methods have found only limited commercial success. 

As a disiafectant or antiseptic, phenol [108-95-2] (carboHc acid) is mosdy of historical iaterest. However, its extensive use continues ia both iavestigative and analytical microbiology, eg, as ia the AO AC phenol coefficient and use-dilution methods. 

In all antiseptic testing, it is recognized that skin and mucous membranes to which products ate appHed cannot be disinfected or sterilized but it is possible to significantly reduce the population of transient and resident pathogenic bacterial flora. AH in vivo test methods requite a deterrnination of the bacteria on the skin before and after treatment. Because of the normal variation in bacterial population of the skin of different people, a number of people must be tested in order to make a statistical analysis of the results. Different parts of the body are used for different tests. In aH of the tests the details of the protocol ate extremely important and must be strictly adhered to in order to obtain reproducible results. 

A simple, quahtative method is the skin stripping technique (322) which strips off a sampling from the skin with ceUophane tape. Methods have been developed (330,331) in which organisms on the hands ate transferred to gloves and sampled. These methods assess both immediate and persistent effects of antiseptics. In aH tests with antiseptics, suitable neutralizing chemicals for the antiseptics employed are necessary so that surviving bacteria may be recovered and counted. Some of these are lecithin, Lubrol W, Polysorbate, and sodium thiosulfate (322). 

Tests have been developed that test different products for their effectiveness as a healthcare personnel handwash (327) evaluate hand disinfectants for use in surgery (333) determine the effectiveness of a surgical hand scmb, ie, the glove juice test (311,329) evaluate antiseptics for the oral cavity to be used in mouthwashes (334,335) and test antiseptics for the periurethral area and appHcation to catheters (336,337). A method used for a test comparing four antiseptic products was adopted as recommended practice by the Association of Practitioners of Infection Control (338). 

Reviews of antiseptics for skin and wound cleansers (341), a review of methods for testing antiseptics (329), and an overaH review of antiseptics and their testing methods (342) ate avaHable. 

In 1989 the CEN/TC 216 (figure 1) was astablished to produce harmonized European test methods for disinfectants and antiseptics used in medicine, veterinary and food hygiene. 

Development of standard test methods for estimating chemical disinfectants and antiseptics... 

Recently, with the development of more advanced and sensitive analytical methods, studies on the fate of pharmaceuticals in WWTP have taken into account the analysis of pharmaceuticals sorbed into sludge (Table 4, and references therein). The antiseptics triclocarban and triclosan and the antibiotic ofloxacin have been reported in sludge at concentrations up to 441, 133, and 58 mg kgdw-1, respectively. Compounds such as the anti-inflammatory ibuprofen, the antiepileptic carbamazepine and the antidepressant fluoxetine have also frequently been reported though at lower levels (11,6 and 3 mg kgdw 1, respectively), whereas the (3-blockers were found at low... 

A TLC method for determination of quaternary ammonium antiseptics was proposed, using silanized silica plates in combination with triiodide ions and UVV densitometry at 400 nm. The method was applied to cetylpyridinium chloride, cetrimide (197c) and the isomers of benzalkonium chloride (197b)420. 

While studying antiseptic and germicidal activity in the thiophene series, several quaternary thenylamines were prepared by the following method (54) ... 

Some of the chemical classes of antiseptics, disinfectants, and sterilants are described briefly in the text that follows. The reader is referred to the general references for descriptions of physical disinfection and sterilization methods. 

Silver forms several compounds or complexes with proteins by the action of silver oxide with gelatin in alkali solution, or with albumin, or by suspension in casein solution and by other methods, Such silver-protein complexes containing from 19 to 23% of silvei are known as mild silver protein and are used as antiseptic solutions. They are readily soluble in... 

Detection and Estimation of Preservatives.—The antiseptics commonly tested for in meat are formaldehyde, formic acid, boric acid and fluorides. The analytical methods used for the detection of these and other antiseptics are given later (see Sausages). 

With these the analysis has the same object as with sausages and meat extracts, namely, the determination of the nutritive value and the detection of any adulteration or change. The determinations made, either separatdy on the liquid and meat or on the product as it stands, are those of the water, ash, fat, nitrogen, aridity of the fat, horseflesh, starch, colouring matters and antiseptics, the methods given under sausages being followed. In this case special importance" attaches also to the examination of the external characters of the tin and to the test for metals. 

Anti-acids, astringents and antiseptic agents may contain a variety of aluminium salts. Organic salts, alumina, the hydroxide and phosphates may be attacked with concentrated hydrochloric acid and diluted to bring the aluminium concentration into the range 10—50 pg ml"1. Alternative procedures for antacids using hydrochloric/nitric acid [67] and extraction with 4M hydrochloric acid [95] have been proposed. For silicates, the sample is best taken up in perchloric/hydrofluoric acid, evaporated to dryness to remove silica, and then the residue dissolved in warm hydrochloric acid [87], In each case the nitrous oxide/acetylene flame is the preferred atom cell, and the method of standard additions may be used to minimise any errors arising from lateral diffusion. 

This element is widely employed in the production of glass and glass fibers, fluxes, antiseptics, and other products. Boron compounds are also widely used in nuclear technology [264]. Boron is an element that occurs at a relatively high concentration level in seawater (4.5 mg/L). Yet, economically acceptable processes for boron extraction from the sea do not exist, despite the fact that methods for its recovery from highly mineralized brines have been available since the beginning of the 1960s [253]. With the development of such methods, attempts were made to determine the lowest concentration levels of the element, at which economical processes could be developed [256, 266]. This critical concentration of boron was at that time estimated to be around 20 mg/L. Currently, the critical concentration of boron is estimated to be 15 mg/L or even somewhat less. 

Brewer, J.H. Sterility tests and methods for assuring sterility. In Antiseptics, Disinfectants, Fungicides and Chemical and Physical Sterilization Reddish, G.F., Ed. Henry Kimpton London, NC, 1957. 

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