Use Of Chloroform Research Articles

A family of doctors over 250 years: innovation and controversy

A family of Watkins doctors originating in the Northamptonshire town of Towcester included 13 doctors in seven generations during 250 years. In each generation there were between one and four doctors. Three doctors involved themselves actively in innovative yet controversial practises, described in their own writings and publications. Timothy Watkins' (1755-1834) own handwritten lecture notes describe the problems affecting an 18th-century man-midwife, while his accounts book provides insights into his lifestyle. The concept of the waterborne spread of cholera during the 1854 epidemic in Towcester is described by Robert Webb Watkins (1822-1901) during the same year as the observations made by John Snow (1813-58). John Webb Watkins (1833-1903) in his MD thesis (1856) describes his use of chloroform in labour in Towcester during the early 1850s, followed by self-experimentation with chloroform administered to him between 40 and 50 times by Sir James Young Simpson (1811-70) in Edinburgh. Descriptions of the two 19th-century general practitioners offer insights into the exemplary extent of their civic involvement in all walks of local community life, and of their family ties.

Isolation and Purification of Triptolide from the Leaves of Tripterygium wilfordii Hook F

Triptolide is an important active component of Tripterygium wilfordii Hook F (TWHF) and possesses anti-inflammatory, immunosuppressive, male anti-fertility, and anticancer properties. A new method combining different techniques, including solid-liquid extraction, liquid-liquid partition, column chromatography and high-speed counter-current chromatography (HSCCC) but avoiding the use of chloroform, was developed for the isolation and purification of triptolide from the leaves of TWHF. 48 mg of triptolide at 96.5% purity was obtained from 1 kg of air-dried leaves of TWHF.

The palladium-catalyzed aerobic kinetic resolution of secondary alcohols: reaction development, scope, and applications.

The first palladium-catalyzed enantioselective oxidation of secondary alcohols has been developed, utilizing the readily available diamine (-)-sparteine as a chiral ligand and molecular oxygen as the stoichiometric oxidant. Mechanistic insights regarding the role of the base and hydrogen-bond donors have resulted in several improvements to the original system. Namely, addition of cesium carbonate and tert-butyl alcohol greatly enhances reaction rates, promoting rapid resolutions. The use of chloroform as solvent allows the use of ambient air as the terminal oxidant at 23 degrees C, resulting in enhanced catalyst selectivity. These improved reaction conditions have permitted the successful kinetic resolution of benzylic, allylic, and cyclopropyl secondary alcohols to high enantiomeric excess with good-to-excellent selectivity factors. This catalyst system has also been applied to the desymmetrization of meso-diols, providing high yields of enantioenriched hydroxyketones.

Joint GC–MS and LC–MS platforms for comprehensive plant metabolomics: Repeatability and sample pre-treatment

Metabolomics nowadays mostly comprises the application of both LC–MS and GC–MS based approaches. Here we investigate different extraction set-ups for these two established analytical platforms in the field of plant metabolomics. Six extraction approaches for Arabidopsis thaliana leaves, varying in extraction solvent composition, extraction temperature and order of solvent addition within the extraction sequence, were analyzed on the two platforms. Our aim was to establish the most suitable analysis protocol, practicable for both LC–MS and GC–MS analysis, in order to obtain as extensive as possible metabolome coverage. One single sample preparation procedure would save time and valuable sample while still offering the complementary datasets generated by GC–MS and LC–MS. All extraction approaches were evaluated based on the following criteria: number of detected m/ z-retention time pairs, heat maps of the detected peaks, and residual enzymatic activity of invertase and phosphatase in the plant leaf extracts. Unsupervised principal component analysis (PCA) was used to evaluate grouping trends between the different extraction approaches. Quality controls, a blend of aliquots of the different extracts, were used to establish a paired evaluation of the repeatability performance of the GC–MS and LC–MS analysis. We conclude that the use of chloroform in the extraction solvent is counterproductive in an untargeted LC–MS metabolomics approach as is heating. Below room temperature (instead of heated) extraction does not significantly degrade GC–MS performance but one should be more cautious with respect to residual enzymatic activity in the plant extract.

An Efficient Organic Solvent Based Extraction Method for the Proteomic Analysis ofArabidopsisPlasma Membranes

Membrane proteins are involved in diverse cellular processes and are an integral component of many signaling cascades, but due to their highly hydrophobic nature and the complexities associated with studying these proteins in planta, alternative methods are being developed to better characterize these proteins on a proteome-wide scale. In our previous work ( Mitra , S. K. et al. J. Proteome Res. 2007 , 6 , ( 5 ), 1933 - 50 ), methanol-assisted solubilization was determined to facilitate the identification of both hydrophobic and hydrophilic membrane proteins compared to Brij-58 solubilization and was particularly effective for leucine-rich repeat receptor-like kinases (LRR RLKs). To improve peptide identification and to overcome sample losses after tryptic digestion, we have developed an effective chloroform extraction method to promote plasma membrane protein identification. The use of chloroform extraction over traditional solid-phase extraction (SPE) prior to off-line strong cation exchange liquid chromatography (SCXC) and reversed-phase liquid chromatography-tandem mass spectrometry (LC/MS/MS) analysis facilitated the removal of chlorophylls, major contaminants of plant tissue preparations that can affect downstream analysis, in addition to the effective removal of trypsin used in the digestion. On the basis of a statistically derived 5% false discovery rate, the chloroform extraction procedure increased the identification of unique peptides for plasma membrane proteins over SPE by 70% which produced nearly a 2-fold increase in detection of membrane transporters and LRR RLKs without increased identification of contaminating Rubisco and ribosomal peptides. Overall, the combined use of methanol and chloroform provides an effective method to study membrane proteins and can be readily applied to other tissues and cells types for proteomic analysis.

Blessed days of anaesthesia: how anaesthetics changed the world

Among all the great discoveries and inventions of the nineteenth century, few offer us a more fascinating insight into Victorian society than the discovery of anaesthesia. Now considered to be one of the greatest inventions for humanity since the printing press, anaesthesia offered pain-free operations, childbirth with reduced suffering, and instant access to the world beyond consciousness. And yet, upon its introduction, Victorian medics, moralists, clergymen, and scientists, were plunged into turmoil. This vivid and engaging account of the early days of anaesthesia unravels some key moments in medical history: from Humphry Davy's early experiments with nitrous oxide and the dramas that drove the discovery of ether anaesthesia in America, to the outrage provoked by Queen Victoria's use of chloroform during the birth of Prince Leopold. And there are grisly ones too: frequent deaths, and even notorious murders. Interweaved throughout the story, a fascinating social change is revealed. For anaesthesia caused the Victorians to rethink concepts of pain, sexuality, and the links between mind and body.From this turmoil, a profound change in attitudes began to be realised, as the view that physical suffering could, and should, be prevented permeated through society, most tellingly at first in prisons and schools where pain was used as a method of social control. In this way, the discovery of anaesthesia left not only a medical and scientific legacy that changed the world, but a compassionate one too.

Dichloromethane as a Solvent for Lipid Extraction and Assessment of Lipid Classes and Fatty Acids from Samples of Different Natures

The usefulness of the solvent mixture dichloromethane/methanol for lipid extraction and the determination of lipid classes and fatty acids in samples of different natures was conducted. Two different extraction methods were compared, one containing chloroform/methanol, another containing dichloromethane/methanol. Total lipid extraction showed some minor differences but no variation in the lipid classes. Regarding the fatty acid profile, in Echium virescens seeds, 17 major fatty acids could be identified and quantified, and all were equally extracted when either solvent system was employed. In Echium acanthocarpum hairy roots, 17 major fatty acids were quantified, showing some statistical differences for one cell line in favor of chloroform. The data obtained from the liquid nutrient medium were also comparable. The cod roe sample showed 31 major fatty acids, showing no statistical differences between the two solvent systems. Contrarily, the CH 2Cl 2 method was able to extract 31 main fatty acids found in European seabass dorsal muscle more efficiently than the CHCl 3 method. The results indicate that, for lipid extraction and fatty acid assessment, dichloromethane/methanol can readily replace the commonly employed chloroform/methanol, thus avoiding the major health, security, and regulatory problems associated with the use of chloroform.

The Antimicrobial Effect of Chloroform on Enterococcus faecalis After Gutta-Percha Removal

The purpose of this in vitro study was to evaluate the antimicrobial effectiveness of chloroform on Enterococcus faecalis when used as a gutta-percha solvent during endodontic retreatment. Bilaterally matched human teeth were instrumented, infected with E. faecalis, and obturated. The gutta-percha was then removed using either chloroform or saline. Bacterial samples were collected after gutta-percha removal and following additional apical enlargement. A significant difference was seen (p < 0.05) between the number of colony forming units (CFU) of E. faecalis for teeth retreated using chloroform (mean 21 + 56 CFU/ml) versus saline (mean 280 + 480 CFU/ml). Negative cultures were obtained in 11 of 17 chloroform samples and none of the saline samples. Samples taken after apical enlargement two sizes larger than the original master apical file showed a significant difference (p < 0.05) between teeth retreated using chloroform versus saline. Negative cultures were seen in 9 of 17 chloroform samples and 1 of 17 saline samples. This study demonstrated that the use of chloroform during endodontic retreatment significantly reduced intracanal levels of cultivatable E. faecalis.

An Unusual Case of Drug-Facilitated Sexual Assault Using Aromatic Solvents

This report documents a case of drug-facilitated sexual assault (DFSA) under the influence of solvents. The victim was a 13-year-old female. Upon contact with law enforcement, she was still confused and could hardly explain the facts. She told authorities that she had been kidnapped 4 h previously when two individuals with covered faces put a cloth soaked in a solvent over her mouth. She spent a few hours in a room, during which she lost consciousness. The girl awakened semi-nude in the street with memory loss. No alcohol was present in the subject's body; no odor of alcohol was detected on the subject's breath. No lesions were observed during a gynecological exam. A blood sample was taken with the intent to investigate the use of chloroform or similar anesthetics. Toxicological analysis of the victim's blood revealed the presence of 7.6 mg/L of benzene, 24.8 mg/L of toluene, and 0.6 mg/L of xylene (mixture of isomers). As for other analytical findings, diazepam (0.02 mg/L) was also found. The aromatic solvents involved in this case were detected using gas chromatography with flame-ionization detection (GC-FID) and confirmed using GC-mass spectrometry (MS) in full scan mode after liquid-liquid extraction of the whole blood sample. Quantitation of the aromatic solvents was carried out using GC-FID. Diazepam was detected using GC with nitrogen-phosphorus detection (NPD) and confirmed using GC-MS with full scan mode after solid-phase extraction of the whole blood sample using Bond-Elut Certify columns. Quantitation of diazepam was carried out using GC-NPD. No other drugs, including ethanol, were detected. Recoveries for benzene, toluene, and xylene (mixture of isomers) in whole blood at 5 mg/L were 89.2%, 90.8%, and 93.4%, respectively. Intraday precisions were 5.3%, 5.0%, and 4.9%, respectively, and interday precisions were 12.1%, 11.6%, and 11.5%, respectively. The limits of detection (LOD) and quantitation (LOQ) were 30 and 100 microg/L, respectively. The linearity of the blood calibration curves was excellent with r(2) values of > 0.999 (range 0.1-10 mg/L). Recovery for diazepam in whole blood at 0.5 mg/L was 88.2% with intraday and interday precisions of 2.0% and 10.8%, respectively. The LOD and LOQ were 6 and 20 microg/L, respectively. The linearity of the blood calibration curve was excellent with r(2) values of > 0.999 (range 0.1-2 mg/L). We want to alert other toxicologists about new or unexpected products that should be taken into account when the surreptitious use of substances in DFSA is suspected.

Use of HPTLC, HPLC, and densitometry for qualitative separation of indole alkaloids fromRauvolfia serpentinaroots

High-performance thin-layer chromatography (HPTLC) has been used for normal-phase separation of the components of hexane, chloroform, methanol, and water extracts of Rauvolfia serpentina roots. Computerized densitometry was used for two-dimensional spectrographic image analysis of the HPTLC plates. High performance liquid chromatography (HPLC) was also used for reversed-phase separation of these extracts. Different chromatograms of R. serpentina root extracts, obtained by use of these techniques, revealed the presence of three marker indole alkaloids, ajmaline, ajmalicine, and reserpine, in all four extracts. Use of chloroform resulted in most efficient extraction of these three alkaloids. The results also showed that defatting with hexane may result in loss of the alkaloids.

Copper‐Catalyzed Cross‐Coupling of Imines, Acid Chlorides, and Organostannanes: A Multicomponent Synthesis of α‐Substituted Amides.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Determination of phenols in waters using micro-pumped multicommutation and spectrophotometric detection: an automated alternative to the standard procedure

An automated and greener spectrophotometric procedure has been developed for the determination of phenol in water at 700 nm. The method uses the reaction between phenol, sodium nitroprusside, and hydroxylamine hydrochloride in a buffered medium at pH 12.3. The flow manifold comprises four solenoid micro-pumps employed for sample and reagent introduction into the reaction coil and to transport the colored product formed to the detector. The linear dynamic range was 50-3,500 ng mL(-1) (R = 0.99997; n = 6) and the method provided a limit of detection (3sigma) of 13 ng mL(-1). The sampling throughput was estimated to be 65 measurements per hour and the coefficient of variation was 0.5% (n = 10) for a 1.0 microg mL(-1) phenol concentration. Recoveries of 92-105% were obtained for phenol determination in spiked water samples at concentration levels from 50 to 5,000 ng mL(-1). The use of multicommutation reduced the reagent consumption 25-fold, the sample consumption 225-fold, and the waste generation 30-fold compared with the batch procedure. The proposed method is an environmentally friendly alternative to the official 4-aminoantipyrine method since it avoids the use of chloroform.

Queen Victoria and chloroform

This contribution discusses the production of chloroform, Queen Victoria’s use of chloroform during labour and the reactions of the medical press and the general public.

Delivered at the Royal College of Pysicians, London. By Robert Bentley Todd, M.D., F.R.S. ON THE PATHOLOGY AND TREATMENT OF CONVULSIVE DISEASES

Delivered at the Royal College of Pysicians, London. By Robert Bentley Todd, M.D., F.R.S. ON THE PATHOLOGY AND TREATMENT OF CONVULSIVE DISEASES

Copper-Catalyzed Cross-Coupling of Imines, Acid Chlorides, and Organostannanes: A Multicomponent Synthesis of α-Substituted Amides

A copper-catalyzed cross-coupling of organotin reagents with imines and acid chlorides is reported. The reaction proceeds efficiently with a range of vinyl-, alkyl-, aryl- and heteroaryl-substituted organostannanes as well as a diverse set of imines of non-enolizable aldehydes. Use of chloroformates also allows for the formation of N-protected alpha-substituted amines. This chemistry has been applied to the synthesis of isoquinoline alkaloid derivatives through the activation of cyclic imines.

Janos Balassa and resuscitation by chest compression

Early efforts at resuscitation in the 18th century involved restoration of the airway followed by artificial respiration [1]. With the development of anaesthesia, cardiac arrest was recognized as a specific entity, particularly following the use of chloroform. This provided the impetus for attempts to maintain artificial circulation by cardiac massage [2]. In 1874, Moritz Schiff, a professor of physiology in Florence, Italy, c c S a a i c l t s c h a F t c

The early steps of chloroform anaesthesia in Turkey during the Ottoman Empire in the 19th century

Objective. – The aim of this study was to research the pioneering steps for the employment of chloroform in Turkey in comparison with the developments in the West i.e. in the United States and in Europe. The development of anaesthesiology in the West started in the first half of the 19th century. As an anaesthetic substance, ether was first employed in a medical operation by R. Liston in December 1846. But taking into consideration of its bronchially irritant effect, British gynaecologist Dr. J.Y. Simpson preferred to utilize chloroform in obstetrical operations in 1847. The paper aims at shedding light on the earlier steps for modern anaesthesiology in Turkey in that sense. Methods. – The survey used evaluation of archival documents, first hand-original sources such as the annual medical reports of the Medical School, books, official journals, and newspapers of the time, and also secondary sources concerned with the subject. Results. – In view of the findings of the survey, chloroform, as an anaesthetic material, began to be administered surgically in Turkey much earlier than it was already known. It was experienced and used in operations at the surgical clinic of the Imperial School of Medicine at the Capital city, Istanbul in 1848. The Crimean War (1853–1855) induced to the prevalent surgical use of chloroform in Istanbul on the soldiers back from the front. In other words, it was evidenced that surgeons started to make use of this anaesthetic substance in the Ottoman Empire, shortly after it was put into medical practice in Europe. Conclusion. – This study deals with that phenomenal progress of chloroform anaesthesia in the medical history in Turkey during the second half of the 19th century.

Copper‐Catalyzed Coupling of Imines, Acid Chlorides, and Alkynes: A Multicomponent Route to Propargylamides.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Copper-catalyzed coupling of imines, acid chlorides, and alkynes: a multicomponent route to propargylamides.

The use of imines in a metal-catalyzed coupling with alkynes and acid chlorides is described. This process proceeds rapidly with CuI as the catalyst and provides an efficient and general three-component coupling method to prepare propargylamides. The coupling can also be diversified to allow the formation of N-carbamate-protected propargylamines with the use of chloroformates.

TLC Profiling of Impurities of 1‐(3,4‐Methylenedioxyphenyl)‐2‐nitropropene an Intermediate in MDMA Synthesis. Influence of Sample Preparation Methods and Conditions

Thin‐layer chromatography (TLC) was employed for screening profiling of impurities of 1‐(3,4‐methylenedioxyphenyl)‐2‐nitropropene, an intermediate product of (3,4‐methylenedioxy)methamphetamine (MDMA) synthesis (from piperonal). Liquid–liquid extraction (LLE) and solid phase extraction (SPE) were applied to isolate impurities from the drug matrix. The SPE extraction process was performed on C8 columns and LLE was carried out using n‐heptane. The influence of buffer solutions (pH 1, 4, 5, 6, 7, 8, 10, 11, 13, and 14) on the extraction efficiency was investigated. The chromatograms were developed with the use of chloroform:ethyl acetate (98:2) mixture. The spots of separated impurities were observed under UV light at λexc = 254 and 366 nm. The proposed semiquantitative criterion of profile (chromatogram) quality has been based on a matrix presentation of TLC patterns. It takes into account the number of spots revealed, differences between R f values, and intensity of fluorescence, simultaneously.