Antibiotic,/3-lactam penicillins

Ponsford RJ (1992) Antibiotics [(3-lactams (penicillins and others)]. Kirk-Othmer Encyclopedia of Chemical Technology, 4th edn, Vol 3. Wiley, New York, pp 129-158. 

ANTIBIOTICS - BETA-LACTAMS - PENICILLINS AND OTHEPE] (Vol 3) d-(L-a-Aminoadipyl)-L-cysteinyl-D-valine (LLD-ACV) [32467-88-2]... 

Derivatiziag an organic compound for analysis may require only a few drops of reagent selected from silylatiag kits suppHed by laboratory supply houses. Commercial syathesis of penicillins requires silylatiag ageats purchased ia tank cars from the manufacturer (see Antibiotics, P-LACTAMS-penicillins AND others). 

Hypersensitivity reactions with P-lactam antibiotics, especially penicillin, may encompass any of the type I through IV Gell-Coombs classifications. The most common reactions are maculopapular and urticarial eruptions.7 While rare (less than 0.05%), anaphylaxis to penicillins causes the greatest concern because they are responsible for the majority of drug-induced anaphylaxis deaths in patients, accounting for 75% of all ana-i phylaxis cases in the United States.5,8 The treatment of ana-I phylaxis is given in Table 51-2.9... 

Development of resistance to P -lactam antibiotics, including penicillins and cephalosporins, has significantly impacted the management of bacterial meningitis. Approximately 17% of United States pneumococcal CSF isolates are resistant to penicillin, and 3.5% of CSF isolates are resistant to cephalosporins.26 The Clinical and Laboratory Standards Institute (CLSI) has set a lower ceftriaxone susceptibility breakpoint for pneumococcal CSF isolates (1 mg/L) than for isolates from non-CNS sites (2 mg/L). Increasing pneumococcal resistance to penicillin G... 

An interesting example of MIP-LC analytics was presented in a paper, which focused on the separation of antibiotics of similar structures. Columns are (commercially) available to separate penicillins ( 3-lactams) from other antibiotics. However, if the quantification of each of the 3-lactam compounds is required, a more selective stationary phase has to be found. Molecular imprinting allows the fabrication of phases specifically for each 3-lactam. If for instance the concentration of the P-lactam oxacillin in a food sample has to be selectively determined, a polymer imprinted with oxacillin is the right choice. Compared to a standard stationary phase, which only allowed the separation of the entire group of (5-lactams from other non-(3-lactam analytes (e. g., bacitracin), the MIP enables the separation of the imprinted species from the pair of non-imprinted 3-lactams penicillin V and penicillin G see Fig. 6 [29,30]. 

Disc Assay - This is the simplist of the procedures and involves the placing of a standard 1/2 disc saturated with milk onto the surface of B. stearothermophilus seeded agar plate and co-incubating with suitable control discs at 55 or 64 C until well-defined zones of inhibition are obtained, usually 3-4 h. Confirmation using penicillinase-treated milk is required. Zones 14.0 mm are positive. The lower limit of detection is 0.008 units penicillin/mL. This type of assay is simple, reasonably rapid and reasonably sensitive. Quantitation is possible by using graded concentrations of penicillin in the control milk. The technique is limited, however, to 3-lactam antibiotics, primarily penicillin ( ). 

Microbial inhibition tests are extremely sensitive for -lactam antibiotics, primarily penicillin, but mostly are more than 100-fold less sensitive for other commonly used antibacterials such as macrolides, sulfonamides, tetracyclines, or chloramphenicol (4, 5). Therefore, inhibition tests usually classify residues as belonging to the -lactam group. Antibiotics other than -lactams and sulfonamides can be detected by use of the enzyme penicillinase and aminobenzoic acid, respectively (1, 6). 

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