Blood methanol

It is critical that the blood methanol level be determined as soon as possible if the diagnosis is suspected. Methanol concentrations higher than 50 mg/dL are thought to be an absolute indication for hemodialysis and treatment with fomepizole or ethanol, although formate blood levels are a better indication of clinical pathology. Additional laboratory evidence includes metabolic acidosis with an elevated anion gap and osmolar gap (see Chapter 59). A decrease in serum bicarbonate is a uniform feature of severe methanol poisoning. 

In a fatality due to the ingestion of about 125 ml of Formaldehyde Solution, the following postmortem concentrations were reported blood, methanol 0.4 pg/ml, formaldehyde, a trace stomach contents, methanol 0.9 g, formaldehyde 4.5 g (B. Finkle, Bull. int. Ass.forens. Toxicol., 1975, //(2), 26). 

Temazepam and morphine have been separated from a whole blood matrix using SC CO2. In the first instance, the extractants were CO2 and ethyl acetate at 65°C and 207 bar, and recoveries ranged from 80% to 100%. The extraction was monitored at 254 nm, with individual separation of the analytes carried out by high-performance liquid chromatography (HPLC). For morphine extraction from dried blood, methanol/triethylamine was added as a modifier to 90% CO2 at 100°C and 241 bar, and the extracts were analyzed by GC-MS. The SFE method proved to be faster and cleaner than solid-phase extraction (SPE). 

Blood Methanolic KOH hydrolysis extraction with hexane cleanup on silica gel and alumina column if necessary GC/ECD 2pg 100 4 at 1.09-109 ng/g Que Hee et al. 1983... 

Majchrowicz, E. Mendelson, J.H. (1971). Blood methanol concentrations during experimentally induced ethanol intoxication in alcoholics. The journal of pharmacology and experimental therapeutics. 179,2,293-300. 

Toxic Volatiles in Alcoholic Coma. Simultaneous Determination of Blood Methanol, Ethanol, Isopropanol, Acetaldehyde, and Acetone by Gas Chromatography... 

The analysis of mefloquine in blood, using packed-column sfc, a mobile phase consisting of / -pentane modified with 1% methanol and 0.15% -butylamine, and electron capture detection has been reported (92). The method compares favorably to a previously pubflshed hplc-based procedure having a detection limit of 7.5 ng/mLin 0.1 mL blood sample. 

Esmolol is iv adrninistered. Maximal P-adrenoceptor blockade occurs in 1 min. Its elimination half-life is about 9 min. EuU recovery from P-adrenoceptor blockade is within 30 min after stopping the infusion. The therapeutic plasma concentrations are 0.4—1.2 lg/mL. It is metabolized by hydrolysis in whole blood by red blood cell esterases resulting in the formation of a primary acid metabohte and free methanol. The metabohte is pharmacologically inactive. The resulting methanol levels are not toxic. Esmolol is 55% bound to plasma protein, the acid metabohte only 10%. Less than 2% of parent dmg and the acid metabohte are excreted by the kidneys. Plasma levels may be elevated and elimination half-hves prolonged in patients with renal disease (41). 

Compounds Causing Cardiovascular Toxicity Alcohols are the most important compounds causing vascular toxicity. Ethanol depresses cardiac muscle and attenuates its contractivity when the concentration of ethanol in the blood exceeds 0.75 mg/100 mL. Ethanol also causes arrhythmias, and a metabolite of ethanol, acetaldehyde, also depresses the heart. Furthermore, high concentrations of acetaldehyde cause cardiac arrhythmias. The cardiovascular toxicity of methanol is about the same as that of ethanol, whereas al cohols with longer chains are more toxic than ethanol. 

The column used for blood serum analysis was 100 cm long, 1 mm in diameter and packed with RP 18 reversed phase having a particle size of 10 pm. A concave gradient program was used to develop the separation over a period of 45 min. at a flow rate of 50 pl/min. The initial solvent was 75% methanol 25% water and the final solvent was pure methanol. 

Since anthocyaifins acylated with aliphatic acids are sensitive to acids, as verified, for example, in fruits of R suberosa when extracted with methanol containing 0.1% HCl," their occurrence in foods may be underestimated. Malonyl acylation in glucose at its position 6 was found in anthocyanins from blood... 

The new lipid occurred only in the plasma hpids of newborns and was not present in membrane hpids of red cell membranes or platelets. Total lipids were extracted from plasma and from red blood cell membranes and platelets. A total lipid profile was obtained by a three-directional PLC using silica gel plates and was developed consecutively in the following solvent mixtures (1) chloroform-methanol-concen-trated ammonium hydroxide (65 25 5, v/v), (2) chloroform-acetone-methanol-ace-tic acid-water (50 20 10 15 5, v/v), and (3) hexane-diethyl ether-acetic acid (80 20 1, v/v). Each spot was scraped off the plate a known amount of methyl heptadecanoate was added, followed by methylation and analysis by GC/MS. The accmate characterization of the new lipid was realized using NMR technique. 

Fused-silica column (15 cm x 4.6 mm) of Spherisorb S5W 0.1 mL chloroform-methanol-aqueous 25% ammonia (868 125 7) [1.5 mL/min] 254 nm Normal phase HPLC analysis in whole blood and urine. [96]... 

Normal phase silica column Chloroform-methanol-ammonia solution (86.8 12.5 0.7) 254 nm Assay of primaquine and hepatic targeting neoglycoalbumin-primaquine in whole blood and liver of mouse by reversed-phase HPLC. [105]... 

Relative extraction efficiencies of polar polymeric neutral, cation, and anion exchange sorbents (HLB, MCX, and MAX) for 11 beta antagonists and 6 beta agonists in human whole blood were probed.109 Initial characterization of MCX and MAX for acidic and basic load conditions, respectively, showed that both the agonists and antagonists were well retained on MCX, while they were recovered from MAX in the wash with either methanol or 2% ammonia in methanol (see Table 1.6). Blood samples were treated with ethanol containing 10% zinc sulfate to precipitate proteins and the supernatants loaded in 2% aqueous ammonium hydroxide onto the sorbents. After a 30% methanol and 2% aqueous ammonia wash, the analytes were eluted with methanol (HLB), 2% ammonia in methanol (MCX), or 2% formic acid in methanol (MAX). The best recoveries were observed with MCX under aqueous conditions or blood supernatant (after protein precipitation) spiked sample load conditions (see Table 1.7). Ion suppression studies by post-column infusion showed no suppression for propranolol and terbutaline with MCX, while HLB and MAX exhibited suppression (see Figure 1.6). 

Cyclosporine D (200 fxg/L) in methanol and ZnS04 (50 g/L) aqueous solution (1 1 v/v) served as the IS. The IS (1.5 mL) was accurately transferred into disposable glass tubes (13 x 100 mm), mixed with 0.5 mL calibration standard, control, or patient sample by vortexing for 30 sec, and centrifuged at 500 g for 2 min. C8 cartridges (conditioned by 1 mL acetonitrile followed by 0.5 mL deionized water) were loaded with whole blood supernatants followed with 1 mL acetonitrile/water wash solution (2 3 v/v), then loaded into the AASP. 

A standard stock solution of sirolimus was prepared in methanol. Controls and standard working solutions were prepared by spiking blank whole blood with the stock solution. Standards, controls, and patient whole blood (10 fi. ) were transferred to 1.5 mL polypropylene tubes, mixed with 40 fiL of 0.1M zinc sulfate solution, precipitated with 100 fiL of methanol containing the IS (2 fig/L), vor-texed vigorously for 5 sec, and centrifuged at 10,500 g for 5 min. Supernatants were collected and assayed. The injection volume was 20 fiL. The retention times of sirolimus and ascomycin were 0.93 and 0.89 min, respectively. The total run time was 2.5 min. Representative MRM chromatograms of a patient sample are shown in Figure 11.6. 

Salm et al.44 developed a high-throughput analytical method to measure cyclosporine in whole blood. They used a simple SPE procedure, followed by HPLC-MS/MS. An Agilent 1100 liquid chromatograph was coupled with an Agilent Zorbax Bonus C18 reversed-phase column (50 x 2.1 mm, 5 jt/rn particle size). The column temperature was maintained at 70°C in a column oven. The mobile phase consisted of 80% methanol and 20% 40mM ammonium acetate buffer (pH 5.1) delivered isocratically at a flow of 0.4 mL/min. D12 cyclosporine was the IS. 

Blank, calibrator, control, and patient whole-blood samples (50 /iL) were transferred into 1.5 mL conical test tubes, mixed with 100 /xL of the IS, vortexed for 10 sec, and centrifuged at 13,000 g for 5 min. Twenty-five microliters of supernatant were injected onto a Cohesive Technologies Cyclone polymeric turbulent flow column (50 x 1 mm, 50 /flushed with a mixture of methanol and water (10 90 v/v) at a flow of 5 mL/min. Column switching from the TFC to HPLC systems was via a Cohesive Technologies system. The analytical column was a Phenomenex Phenyl-Hexyl-RP (50 x 2.1 mm, 5 /.mi). The mobile phase consisted of methanol and ammonium acetate buffer (97 3 v/v). The buffer was 10mM ammonium acetate containing 0.1% v/v acetic acid. The flow rate was 0.6 mL/min. 

Blood, brain, lungs Solvents (methanol, toluene, hydrocarbons) Color tests GC Head-space LEE GC GC-MS... 

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