Aqueous solutions for injection

The initial formulation for most drugs is to allow basic in vivo toxicology, pharmacology and biopharmaceutical assessments to be conducted. Aqueous solutions for injection are optimum for this application since the entire dose is administered at a single time point and the problem of bioavailability does not arise. It is important that these formulations are considered carefully, particularly for drugs that are poorly water soluble, because potentially useful compounds may be rejected inadvertently. These early formulations are also crucial because they set an in vivo benchmark for the drug s future performance. 

Liquid Dosage Forms Sodium nitropruside in aqueous solution for injection will remain stable for up to one year if protected from light however, its shelf life is about 4h when exposed to normal room light [35]. It has been reported that uric acid increases the photostability of sulfathiazole sodium in solutions [36]. Further dZ-methionine increased the photostability of ascorbic acid in solution [37]. The... 

Jeong B, Lee KM, Gutowska A, An YH. Thermogelling biodegradable copolymer aqueous solutions for injectable protein delivery and tissue engineering. Biomacromolecules 2002 3(4) 865-868. 

It is necessary to study stability in solution in the solvent used to prepare sample solutions for injection in order to establish that the sample solution composition, especially the analyte concentration, does not change in the time elapsed between the preparation of the solution and its analysis by HPLC. This is a problem for only a few types of compound (e.g. penicillins in aqueous solution) when the sample solution is analysed immediately after the preparation of the sample solution to be injected. The determination of stability in solution is more of an issue when sample solutions are prepared and then analysed during the course of a long autosampler run. While the acceptance criteria for stabUity in solution may be expressed in rather bland terms by making a statement such as, e.g. the analyte was sufficiently stable in solution in the solvent used for preparing sample solutions for reliable analysis to be carried out , in practice it has to be shown that within the limits of experimental error, the result of the sample solution analysis by the HPLC method is the same for injections at the time for which stability is being validated as for injections immediately subsequent to the sample solution preparation. While this may be done by a subjective assessment of results with confidence limits, strictly speaking a statistical method known as the Student s t-test should be used. 

Ascorbic acid is used as an antioxidant in aqueous pharmaceutical formulations at a concentration of 0.01-0.1% w/v. Ascorbic acid has been used to adjust the pH of solutions for injection, and as an adjunct for oral liquids. It is also widely used in foods as an antioxidant. Ascorbic acid has also proven useful as a stabilizing agent in mixed micelles containing... 

Because it is bitter, this antibiotic is administered orally cither in capsules or as the palmitatc e.ster. Chloramphenicol palmitate is insoluble in water and may be suspended in aqueous vehicles for liquid dosage forms. The ester forms by reaction with the hydroxyl group on C-3. In the alimentary tract, it is hydrolyzed slowly to the active antibiotic. Chloramphenicol is administered parenterally as an aqueous suspensiuti of very fine cry.stals or as a solution of the sodium salt of the succinate ester of chloramphenicol. Sterile chloramphenicol sodium succinate has been used to prepare aqueous. solutions for intravenous injection. 

Containers for blood, aqueous solutions, infusions, injections, irrigation solutions. 

Locai anesthetic agents generaiiy are prepared in various dosage forms aqueous solutions for parenterai injection, and creams and ointments for topicai appiications. Thus, chemical stability and aqueous soiubiiity become primary factors in the preparations of suitable pharmaceutical dosage forms. 

Palytoxins are stable in neutral aqueous solutions for prolonged periods [104,105]. However, rapid decomposition occurs, with loss of toxicity, under acid or alkaline conditions [2,7,96,105,106]. Palytoxin is also detoxified by bleach [96]. Catalytic hydrogenation greatly decreases toxicity, and no effects were seen in mice after injection of perhydropalytoxin at 9.2 mg/kg [106]. Toxicity is also decreased following acetylation of the terminal amino group [106]. 

Dilute solutions of the sample dissolved in a weak solvent (e.g., aqueous sample solutions for injection onto a reversed-phase column). 

Fig. 78. Kinocilia with a vesicular component in the outer zone alongside the axonema. Bronchiolar epithelial cell of a female rat (breeder Winkehnann, Borchen-Kirchborchen) treated with 150 mg DL-a-tocopherol acetate per kg body weight X day, 5 days per week. The colloidal aqueous solution was injected intamuscularly from April 12 to June 20, 1967 for a total of 45 days. Fixed under mefhitural anaesthesia by intratracheal instillation of 2.5 % glutaraldehyde in phosphate buffer (pH 7.4) before opening the thorax. After washing in phosphate buffer the tissue was postfixed with 1 % osmium tetroxide in phosphate buffer for 2 h. Contrasted en bloc for 12 h with 0.5 % uranyl acetate in 70 % ethanol. Embedded in a 2 8 mixture of methyl and butyl methacrylate. Sectioned at 50 nm. Lead citrate after Reynolds (1963). Plate 31/10...

The results of field tests on 250 units over an 18-month period have been summarized by Fbwler (1964). Calcium chloride has also been proposed for hydrate prevention in natural-gas gathering lines. In this application an aqueous solution is injected near the well head and collected at the downstream point after gas cooling has occurred. In tests reported in Russian literature (Andiyudichenko and Vasilchenko, 1963), the process was found to be very effective. However, purging of the solutions with natural gas prior to injection was found necessary to reduce their corrosive action. 

SPME has been utilized for deterrnination of pollutants in aqueous solution by the adsorption of analyte onto stationary-phase coated fused-siUca fibers, followed by thermal desorption in the injection system of a capillary gas chromatograph (34). EuU automation can be achieved using an autosampler. Eiber coated with 7- and 100-p.m film thickness and a nitrogen—phosphoms flame thermionic detector were used to evaluate the adsorption and desorption of four j -triazines. The gc peaks resulting from desorption of fibers were shown to be comparable to those obtained using manual injection. 

A flow-injection system with electrochemical hydride generation and atomic absorption detection for the determination of arsenic is described. This technique has been developed in order to avoid the use sodium tetrahydroborate, which is capable of introducing contamination. The sodium tetrahydroborate (NaBH ) - acid reduction technique has been widely used for hydride generation (HG) in atomic spectrometric analyses. However, this technique has certain disadvantages. The NaBH is capable of introducing contamination, is expensive and the aqueous solution is unstable and has to be prepared freshly each working day. In addition, the process is sensitive to interferences from coexisting ions. 

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