Gamma-butyrolactone Research Articles

Measurement and correlation of solubility of succinic anhydride in pure solvents and binary solvent mixtures

The solubility of succinic anhydride in pure solvents and binary {gamma-butyrolactone (GBL)+tetrahydrofuran (THF)} mixtures was determined at a limited temperature range of (283.15–323.15)K by using a gas chromatography method. The experimental results revealed two aspects. On the one hand, the solubility of succinic anhydride increased monotonically with rising temperature in binary (gamma-butyrolactone+tetrahydrofuran) mixtures when solvent composition remains constant. On the other hand, the solubility of succinic anhydride decreased monotonically with the increasing tetrahydrofuran content when temperature remains constant. The modified Apelblat equation, λh equation, CNIBS/R-K equation and Jouyban-Acree equation were successfully used to correlate the experimental solubility in diverse solution systems. Furthermore, the mixing thermodynamic properties of succinic anhydride in binary solvent mixtures were calculated and discussed. The results indicate that the mixing process of succinic anhydride in the investigated solvents is spontaneous.

Volatile Organic Compound Gamma-Butyrolactone Released upon Herpes Simplex Virus Type -1 Acute Infection Modulated Membrane Potential and Repressed Viral Infection in Human Neuron-Like Cells.

Herpes Simplex Virus Type -1 (HSV-1) infections can cause serious complications such as keratitis and encephalitis. The goal of this study was to identify any changes in the concentrations of volatile organic compounds (VOCs) produced during HSV-1 infection of epithelial cells that could potentially be used as an indicator of a response to stress. An additional objective was to study if any VOCs released from acute epithelial infection may influence subsequent neuronal infection to facilitate latency. To investigate these hypotheses, Vero cells were infected with HSV-1 and the emission of VOCs was analyzed using two-dimensional gas chromatograph/mass spectrometry (2D GC/MS). It was observed that the concentrations of gamma-butyrolactone (GBL) in particular changed significantly after a 24-hour infection. Since HSV-1 may establish latency in neurons after the acute infection, GBL was tested to determine if it exerts neuronal regulation of infection. The results indicated that GBL altered the resting membrane potential of differentiated LNCaP cells and promoted a non-permissive state of HSV-1 infection by repressing viral replication. These observations may provide useful clues towards understanding the complex signaling pathways that occur during the HSV-1 primary infection and establishment of viral latency.

Lead free CH3NH3SnI3 perovskite thin-film with p-type semiconducting nature and metal-like conductivity

Lead free CH3NH3SnI3 perovskite thin film was prepared by low temperature solution processing and characterized using current sensing atomic force microscopy (CS-AFM). Analysis of electrical, optical, and optoelectrical properties reveals unique p-type semiconducting nature and metal like conductivity of this material. CH3NH3SnI3 film also showed a strong absorption in visible and near infrared spectrum with absorption onset of 1.3 eV. X-ray Diffraction analysis and scanning electron microscopy (SEM) confirmed a structure of this compound and uniform film formation. The morphology, film uniformity, light harvesting and electrical properties strongly depend on preparation method and precursor solution. CH3NH3SnI3 films prepared based on dimethylformamide (DMF) showed higher crystallinity and light harvesting capability compared to the film based on combination of dimethyl sulfoxide (DMSO) with gamma-butyrolactone (GBL). Local photocurrent mapping analysis showed that CH3NH3SnI3 can be used as an active layer and have a potential to fabricate lead free photovoltaic devices.

P001 In 2015, MSM accessing PEPSE is significantly more associated with club drug use than 2013/2014

Background/introduction Recreational drug (RD) use is increasing in men who have sex with men (MSM) and increases sexual risk taking behaviour and possibly increasing attendances for PEPSE. Aim(s)/objectives To identify Club drug use during PEPSE attendances in MSM in 2013/4 compared to 2015. Methods Review PEPSE (MSM) attendance during two 4-month periods: November 2013 to February 2014 and March 2015 to June 2015. Results 152 MSM attended for PEPSE: 51 in 2013/4 and 101 in 2015. The median age was 31 (18–79) years. Documentation of Club drug use during PEPSE episode increased significantly from 27/51 (53%) in 2013/14 to 100/101 (99%) during 2015 (p gamma -Butyrolactone(GBL), Mephedrone and Crystal Meth being the most frequent reported. Discussion/conclusion Episodes of unsafe sex leading to access of PEPSE appear to be more associated with club drug use in 2015 than in 2013/4 and our documentation of this has improved. Identification of club drug use in MSM is an important harm intervention.

The behavioural profile of gamma-hydroxybutyrate, gamma-butyrolactone and 1,4-butanediol in humans.

Gamma-hydroxybutyrate (GHB) is a putative neurotransmitter, a drug of abuse, and a medical treatment for narcolepsy and other neuropsychiatric disorders. Its precursors gamma-butyrolactone (GBL) and 1,4-butanediol (1,4-BD) are endogenously converted to GHB and thereby exert their psychobehavioural effects. In humans, GHB has a wide spectrum of properties ranging from stimulation and euphoria in lower doses, to sedation, deep sleep, and coma after ingestion of high doses. However, behavioural studies in healthy volunteers remain scarce and are usually limited to psychomotor performance testing. Most available data arise from either qualitative studies with illicit users or clinical trials examining therapeutic properties of GHB (then usually termed sodium oxybate). Here, we present an overview of the behavioural effects of GHB, GBL, and 1,4-BD in these three populations. GHB and its precursors strongly influence behaviours related to core human autonomic functions such as control of food intake, sexual behaviour, and sleep-wake regulation. These effects are instrumentalised by illicit users and clinically utilised in neuropsychiatric disorders such as narcolepsy, fibromyalgia, and binge-eating syndrome. Considering the industry withdrawal from psychopharmacology development, repurposing of drugs according to their behavioural and clinical profiles has gained increasing relevance. As such, GHB seems to be an attractive candidate as an experimental therapeutic in depression.

Electrical double layer in surface-inactive electrolyte solution and adsorption of halide ions from 0.1 M solutions on liquid Cd–Ga and In–Ga alloys in gamma-butyrolactone

The double-layer characteristics of liquid renewable Cd–Ga (0.3 at % Cd) and In–Ga (14.2 at % In) electrodes in the gamma-butyrolactone (GBL) solutions of various electrolytes are studied by measuring the differential capacitance and using the method of open-circuit jet electrode. For the (Cd–Ga)/GBL and (In–Ga)/GBL interfaces, the zero-charge potentials, which are not distorted by the specific adsorption of ions, and the chemisorption potential drops of solvent are determined. It is shown that, in spite of the fact that the work function decreases as we pass from (In–Ga) to (Cd–Ga), the chemisorption potential drops of solvent on both electrodes are close. This behavior is explained by a closer approach of GBL dipoles to the surface of (Cd-Ga) electrode providing more effective overlapping of donor–acceptor levels of metal and solvent. It is shown that, in GBL, the adsorption parameters of halide ions and their surface activity series depend on the metal nature. On the (Cd–Ga) and (In–Ga) electrodes, the reversed surface activity series of halide ions is observed: on the Hg electrode in various solvents, the surface activity increases in the series Cl– < Br– < I–, whereas on the (Cd–Ga) and (In–Ga) electrodes in GBL, it varies in the reverse series I– < Br– < Cl–.

The hippocampus participates in a pharmacological rat model of absence seizures

ObjectiveUsing the gamma-butyrolactone (GBL) model of absence seizures in Long–Evans rats, this study investigated if 2.5–6Hz paroxysmal discharges (PDs) induced by GBL were synchronized among the thalamocortical system and the hippocampus, and whether inactivation of the hippocampus affected PDs. MethodsLocal field potentials were recorded by chronically implanted depth electrodes in the neocortex (frontal, parietal, visual), ventrolateral thalamus and dorsal hippocampal CA1 area. In separate experiments, multiple unit recordings were made at the hippocampal CA1 pyramidal cell layer, or the mid-septotemporal hippocampus was inactivated by local infusion of GABAA receptor agonist muscimol. ResultsAs PDs developed following GBL injection, coherence of local field potentials at 2.5–6Hz increased between the hippocampus and thalamus, and between the hippocampus and the neocortex. Hippocampal theta rhythm was disrupted when GBL induced immobility in the rats. The probability of hippocampal multiple unit firing significantly increased at 40–80ms prior to the negative peak of thalamic PDs. Coherence between hippocampal multiple unit activity and thalamic field potentials at 2.5–6Hz was significantly increased after GBL injection. Muscimol infusion to inactivate the mid-septotemporal hippocampus, as compared to saline infusion, significantly decreased the peak frequency of the PDs induced by GBL, decreased 30–120Hz hippocampal gamma power, and hastened the transition of PDs to 1–2Hz slow waves. SignificanceDuring GBL induced 2.5–6Hz PDs, a hallmark of absence seizure, increased synchronization between the hippocampus and the thalamocortical network was indicated by frequency and temporal correlation analysis. These results suggest that the hippocampus was entrained by thalamocortical activity in the present model of absence seizures. Prolonged synchronization of the hippocampus may result in synaptic alterations that may explain the cognitive and memory deficits in some patients with absence seizures and absence status epilepticus.

Optogenetic activation of superior colliculus neurons suppresses seizures originating in diverse brain networks

Because sites of seizure origin may be unknown or multifocal, identifying targets from which activation can suppress seizures originating in diverse networks is essential. We evaluated the ability of optogenetic activation of the deep/intermediate layers of the superior colliculus (DLSC) to fill this role. Optogenetic activation of DLSC suppressed behavioral and electrographic seizures in the pentylenetetrazole (forebrain+brainstem seizures) and Area Tempestas (forebrain/complex partial seizures) models; this effect was specific to activation of DLSC, and not neighboring structures. DLSC activation likewise attenuated seizures evoked by gamma butyrolactone (thalamocortical/absence seizures), or acoustic stimulation of genetically epilepsy prone rates (brainstem seizures). Anticonvulsant effects were seen with stimulation frequencies as low as 5 Hz. Unlike previous applications of optogenetics for the control of seizures, activation of DLSC exerted broad-spectrum anticonvulsant actions, attenuating seizures originating in diverse and distal brain networks. These data indicate that DLSC is a promising target for optogenetic control of epilepsy.

Solubilities and thermodynamic properties of SO2 in five biobased solvents

Five biobased solvents (BBSs) with high boil point, namely ethyl levulinate (EL), butyl levulinate (BL), dibutyl succinate (DBS), gamma-butyrolactone (GBL) and gamma-valerolactone (GVL), were applied in absorption of SO2. The solubilities of SO2 in the BBSs were determined at temperatures (293.15 to 333.15)K and pressures (0 to 120)kPa. Henry’s constant and thermodynamic properties (standard dissolution Gibbs energy, dissolution enthalpy, dissolution entropy) were further calculated according to the solubility data. The gravimetric solubilities in BBSs changed with the sequence of GBL>GVL>EL>BL>DBS. The solubility of SO2 and absorption enthalpy in present BBSs and other molecular solvents as well as ionic liquids (ILs) were systemically compared. The results illustrated that GBL and GVL possessed the potentiality to capture SO2 among all absorbents due to their relatively large solubility and low absorption enthalpy for SO2, biodegradability, low toxicity, inexpensive cost and low viscosity.

The physical and electrochemical properties of poly(vinylidene chloride-co-acrylonitrile)-based polymer electrolytes prepared with different plasticizers

Lithium ion-conducting membranes with poly(ethylene oxide) (PEO)/poly(vinylidene chloride-co-acrylonitrile) (PVdC-co-AN)/lithium perchlorate (LiClO4) were prepared by solution casting method. Different plasticizers ethylene carbonate (EC), propylene carbonate (PC), gamma butyrolactone (gBL), diethyl carbonate (DEC), dimethyl carbonate (DMC), and dibutyl phthalate (DBP) were complexed with the fixed ratio of PEO/PVdC-co-AN/LiClO4. The preparation and physical and electrochemical properties of the gel polymer electrolytes have been briefly elucidated in this paper. The maximum ionic conductivity value computed from the ac impedance spectroscopy is found to be 3 × 10−4 S cm−1 for the EC-based system. From DBP-based system down to EC-based system, a decrease of crystallinity and an increase of amorphousity are depicted by X-ray diffraction technique, the decrease of band gap energy is picturized through UV–visible analysis, the decrease of glass transition temperature is perceived from differential scanning calorimetry plots, and the reduction of photoluminescence intensity is described through photoluminescence spectroscopy study at an excitation wavelength of 280 nm. Atomic force microscopic images of EC-based polymer electrolyte film show the escalation of micropores. Fourier transform infrared spectroscopy study supports the complex formation and the interaction between the polymers, salt, and plasticizer. The maximum thermal stability is obtained from thermogravimetry/differential thermal analysis, which is found to be 222 °C for the sample complexed with EC. The cyclic voltagram of the sample having a maximum ionic conductivity shows a small redox current at the anode, and cathode and the chemical stability is confirmed by linear sweep voltammetry.

Erratum to “Acute combined poisoning with the new designer drug 4-methyl-N-ethyl-cathinone (4-MEC) and gammabutyrolactone (GBL): A case report with different analytical approaches for identification of some metabolites” [Toxicol. Anal. Clin. 26 (2014) 119–27

Erratum to “Acute combined poisoning with the new designer drug 4-methyl-N-ethyl-cathinone (4-MEC) and gammabutyrolactone (GBL): A case report with different analytical approaches for identification of some metabolites” [Toxicol. Anal. Clin. 26 (2014) 119–27

Hexafluorophosphate intercalation into graphite electrode from gamma-butyrolactone solutions in activated carbon/graphite capacitors

In our recent work, the solvent of ethylene carbonate (EC) has been found to retard the intercalation of anions into graphite electrodes. Here we demonstrate that gamma-butyrolactone (GBL) also exhibits suppressive effect on the intercalation of PF6− into the interlayer space between the graphene planes. The intercalation process of PF6− into graphite electrode from GBL has been investigated by in situ XRD, in situ Raman and EQCM. Furthermore, the effect of GBL has been compared with those of EC and propylene carbonate (PC).

Illicit drug use in sexual settings (‘chemsex’) and HIV/STI transmission risk behaviour among gay men in South London: findings from a qualitative study

Background‘Chemsex’ is a colloquial term used in the UK that describes sex under the influence of psychoactive substances (typically crystal methamphetamine, mephedrone and gamma-hydroxybutyric acid (GHB)/gamma-butyrolactone (GBL)). Recently, concern has...

Screening for Selected Club Drugs Utilizing LC/MS Direct Urine Analysis

A simple liquid chromatography mass spectrometric method with direct urine injection analysis was developed and validated for the identification and quantification of gammahydroxybutyric acid (GHB), gamma-butyrolactone (GBL), 1,4-butanediol (1,4-BD), methylenedioxyn- methylamphetamine (MDMA), 3,4-methylenedioxy-amphetamine (MDA), 3,4-methylenedioxy-Nethylamphetamine (MDEA), ketamine (KET) and norketamine (Nor-KET). GHB-d6, GBL-d6, MDMA-d5, and KET-d4 were used as internal standards (IS). The method has the advantage of one step sample preparation which includes an appropriate dilution and filtration before its injection into the LC/MS system. The protonated ions of the analytes were detected and quantified using an ESI probe operating in positive mode and selected ion monitoring (SIM). The linear range was between 8-20 μg/mL for GHB, GBL and 1,4-BD, 50- 1000 ng/mL for MDEA, KET and Nor-KET and 250-1000 ng/mL for MDMA and MDA, providing square correlation coefficient (r2) ≥ 0.98. Interday and intraday errors were found to be ≤ 13.53%. The applicability of the proposed direct injection LC/MS method was confirmed with the analysis of ten authentic samples initially tested for amphetamines through a preliminary immunoassay screening. In addition, eight samples were assayed for KET and Nor-KET and six samples for GHB, GBL and 1,4-BD. The method is simple, accurate and possesses better specificity comparing to the immunoassay techniques, which make it suitable for screening purposes. It also presents the same or lower cost comparing to the respective immunoassay kit, where available. Toxicological laboratories may use the proposed method, overcoming thus the appeared false positive results (amphetamines) or the absence of immunoassay kits (GHB, GBL, 1,4-BD, KET, Nor-KET), avoiding also the use of increased cost instrumentation such as a liquid chromatography tandem mass spectrometry. Keywords: Amphetamines, date-rape drugs, GHB, ketamine, mass spectrometry, urine.

Carbonate Free Electrolyte for Lithium Ion Batteries Containing γ-Butyrolactone and Methyl Butyrate

A novel carbonate free electrolyte, 1 M lithium difluoro(oxalato) borate (LiDFOB) in 1:1 gamma-butyrolactone (GBL)/methyl butyrate (MB), has been compared to a standard electrolyte, 1 M LiPF6 in 1:1:1 EC/DMC/DEC, and a 1 M LiDFOB in 1:1:1 EC/DMC/DEC electrolyte. The conductivity of 1 M LiDFOB in GBL/MB is higher at low temperature, but slightly lower at higher temperature compared to the standard electrolyte. The 1 M LiDFOB in GBL/MB electrolyte has comparable cycling performance to the standard electrolyte, and better cycling performance than the 1 M LiDFOB in EC/DMC/DEC electrolyte. The reversible cycling performance suggests that the LiDFOB in GBL/MB electrolyte forms a stable anode solid electrolyte interface (SEI) in the presence of GBL. Ex-situ surface analysis of the extracted electrodes has been conducted via a combination of XPS, FTIR-ATR and SEM which suggests that the stable anode SEI results is primarily composed of reduction products of LiDFOB.

Acute combined poisoning with the new designer drug 4-methyl-N-ethyl-cathinone (4-MEC) and gammabutyrolactone (GBL): A case report with different analytical approaches for identification of some metabolites

Summary Objective 4-Methyl-N-ethylcathinone (4-MEC) is a novel designer drug of the β-keto amphetamine family. A case of a mixed poisoning by 4-MEC and gamma-butyrolactone (GBL) is described. Two and half hours after an injected 0.25–0.5 g 4-MEC dose and thirty minutes after GBL ingestion, a 39-year-old man became unconscious and presented after admission to the hospital, transient apnea needing oxygenation and stimulation. After 30 min, he woke up, but remained confused for 4 hours. He was discharged 13 hours later without particular symptoms. For confirmation of the poisoning, different analytical procedures such as HPLC-UV/DAD, GC-MS, UPLC-MS/MS, and LC-HR-MS/MS were applied. Blood and urine levels (8 h after injection) were respectively 353 μg/L and 100 mg/L for 4-MEC and 300 mg/L and 1000 mg/L for gamma-hydroxybutyric acid. In urine, three metabolites (dihydro-, nor-, and nor-dihydro-4-MEC) could be identified for the first time and were similar to those described for other molecules of this class.

P40: A case report of persistent near-fatal anion gap acidosis due to a massive gamma-butyrolactone (GBL)/ethanol intoxication

Case We report a case of an intentional massive gamma-butyrolactone (GBL) intoxication, the precursor of the recreational drug gamma-hydroxybutyric acid (GHB), resulting in life-threatening metabolic acidosis (pH 6.5) with a highly increased anion- and osmolal gap. Rapid analysis using gas chromatography revealed no methanol nor ethylene glycol but a GHB plasma concentration of 4398 mg/L, far above the upper limit concentration found in fatalities attributed to GBL. Full recovery was established following supportive treatment including hemodialysis. This is the first report of GBL intoxication as a cause of high serum anion- and osmolal gap metabolic acidosis. Conclusions GHB/GBL is not a substance classically associated with high anion gap metabolic acidosis (HAGMA), but the finding of the massive GHB concentration was a direct result of the method used in this lab, allowing the simultaneous detection of several substances potentially causing HAGMA (P. Van Hee et al. , Clin. Chem. Lab. Med. 2004; 42(11):1341-1345). Classical ethylene glycol methods would not measure GHB and suitable GC-MS techniques for rapid detection of this illicit drug are not widely available. Here, we propose that GBL/GHB intoxication should be considered in the differential diagnosis of this acid-base disorder. In view of the persistent acidosis, hemodialysis was life-saving.

GHB, GBL and 1,4-BD Addiction

A growing body of evidence shows that gamma-hydroxybutyric acid (GHB) is an addictive substance. Its precursors gammabutyrolactone (GBL) and 1,4-butanediol (1,4-BD) show the same properties and may pose even more risks due to different pharmacokinetics. There are indications that problematic GHB use is increasing in the European Union. This review investigates the existing literature on the neurochemistry of GHB and its precursors, their acute toxicity, addiction potential and withdrawal, the proposed molecular mechanism underlying addiction and the treatment of withdrawal and addiction. Current evidence shows that GHB and its precursors are highly addictive, both in humans and animals, probably through a GABAB receptor related mechanism. Severity of withdrawal symptoms can be considered as a medical emergency. Recent studies suggest that benzodiazepines are not very effective, showing a high treatment resistance, whereas detoxification with pharmaceutical GHB proved to be successful. However, relapse in GHB use is frequent and more research is warranted on relapse prevention. This might aid medical practitioners in the field and improve general understanding of the severity of addiction to GHB, GBL and 1,4-BD.

Poly(ether sulfone) (PES) hollow-fiber membranes prepared from various spinning parameters

A steam/dry/wet phase inversion method was used to fabricate hollow-fiber membranes for ultrafiltration (UF) applications from polyethersulfone (PES) as a polymer material, gamma butyrolactone (GBL) as a solvent and polyethylene glycols (PEGs) as a pore-former additive. Pure water, 30wt.% ethanol and 30wt.% isopropanol were used as bore fluids. The effect of PEG concentration, type of bore fluid, and bore fluid flow rate (BFR) on the structure, permeability, separation performance and mechanical properties of PES hollow fiber was studied. The PES hollow-fiber membranes were characterized by scanning electron microscopy (SEM), capillary flow porometer and porosity measurement. From the results it was found that all PES hollow fibers have a sponge-like structure in the cross-sectional area. Using 30% ethanol as a bore fluid produced fiber with pore density higher than that produced using water or 30% isopropanol. With an increase of the bore fluid rate from 7.67 to 23.06g/min, the pore density and the PWP increased from 14,698.6 to 29,440.2 (pores/mm2×102) and from 45.2 to 107.4l/m2·h·bar respectively, with a minor change in protein rejection. The mechanical properties in terms of Young's modulus, tensile strength and elongation at break were dependent on PEG concentration, and bore fluid type and concentration.

Production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) by Burkholderia sacchari using wheat straw hydrolysates and gamma-butyrolactone

Burkholderia sacchari DSM 17165 is able to grow and produce poly(3-hydroxybutyrate) both on hexoses and pentoses. In a previous study, wheat straw lignocellulosic hydrolysates (WSH) containing high C6 and C5 sugar concentrations were shown to be excellent carbon sources for P(3HB) production.Using a similar feeding strategy developed for P(3HB) production based on WSH, fed-batch cultures were developed aiming at the production of the copolymer P(3HB-co-4HB) (poly(3-hydroxybutyrate-co-4-hydroxybutyrate)) by B. sacchari. The ability of this strain to synthesize P(3HB-co-4HB) was first shown in shake flasks using gamma-butyrolactone (GBL) as precursor of the 4HB units.Fed-batch cultures using glucose as carbon source (control) and GBL were developed to achieve high copolymer productivities and 4HB incorporations. The attained P(3HB-co-4HB) productivity and 4HB molar% were 0.7g/(Lh) and 4.7molar%, respectively. The 4HB incorporation was improved to 6.3 and 11.8molar% by addition of 2g/L propionic and acetic acid, respectively. When WSH were used as carbon source under the same feeding conditions, the values achieved were 0.5g/(Lh) and 5.0molar%, respectively.Burkholderia sacchari, a strain able to produce biopolymers based on xylose-rich lignocellulosic hydrolysates, is for the first time reported to produce P(3HB-co-4HB) using gamma butyrolactone as precursor.