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Background and Objective: Glycyrrhiza glabra L. (GG) and Strychnos nux-vomica L. (NV) are traditional Chinese medicines (TCMs). Changes in the chemical composition may occur before and after the GG-NV compatibility. Ultra-performance liquid chromatography Q-exactive Orbitrap mass spectrometry (UPLC-QE-Orbitrap-MS) was applied here to study the difference in the components of the GG and NV decoctions before and after they were combined. The changes in the chemical composition of GG and NV before and after the combination were determined., Methods: The precise molecular weight, retention time, and fragment ion peak of the different components of the decoctions before and after compatibility were obtained through UPLC-QE-Orbitrap-MS. Differential analysis methods, such as principal component analysis, were used for comparison., Results: In the positive ion mode, 200 new components were added, whereas six components were lost. In the negative ion mode, 144 new compounds were identified, whereas three components were missing., Conclusions: The compatibility difference between GG and NV was studied through UPLC-QE-Orbitrap-MS. The chemical composition of GG and NV changed before and after compatibility, and a class of compounds different from GG and NV was identified in the co-decoction. This study provides an experimental basis for subsequent research into detoxification mechanisms of the GG-NV combination and offers a new analytical method for investigating the compatibility of various other TCM pairs., (© 2024 John Wiley & Sons Ltd.)

Determination of the solution conformation of both small organic molecules and peptides in water remains a substantial hurdle in using NMR solution conformations to guide drug design due to the lack of easy to use alignment media. Herein we report the design of a flexible compressible chemically cross-linked poly-4-acrylomorpholine gel that can be used for the alignment of both small molecules and cyclic peptides in water. To test the new gel, residual dipolar couplings (RDCs) and J-coupling constants were used in the configurational analysis of strychnine hydrochloride, a molecule that has been studied extensively in organic solvents as well as a small cyclic peptide that is known to form an α-helix in water. The conformational ensembles for each molecule with the best fit to the data are reported. Identification of minor conformers in water that cannot easily be determined by conventional NOE measurements will facilitate the use of RDC experiments in structure-based drug design., (© 2021 Wiley-VCH GmbH.)

A simple, rapid, cost-effective and green analytical method is developed based on ultrasound-assisted dispersive liquid-liquid microextraction (US-DLLME) coupled to thin-layer chromatography (TLC)-image analysis for the simultaneous determination of two major alkaloids of Strychnos nux-vomica L i.e., strychnine and brucine. The method is composed of three steps, namely (i) US-DLLME by injecting a mixture of 100-μL chloroform (extraction solvent) and 1-mL methanol (disperser solvent) in 5 mL of aqueous sample, followed by ultrasonication and centrifugation, (ii) TLC of 20 μL of sedimented phase with methanol: ammonia (100:1.5, v/v) as the mobile phase and visualization under ultraviolet radiation (254 nm) and (iii) photography of TLC plate and quantification of spots by image analysis using freely available imageJ software (National Institute of Health, Bethesda, MD, USA). The limit of detection and limit of quantification for both alkaloids were found to be in the range of 0.12-0.15 and 0.36-0.48 μg/spot, respectively. The method was found to be linear in the range of 0.5-5 μg/spot with correlation coefficient (R2) of 0.995 and 0.997 for strychnine and brucine, respectively. The developed method was successfully applied for the determination of strychnine and brucine in Ayurvedic formulations and blood samples. The method does not require any sophisticated instrument and handling skills and can be adopted for rapid analysis of strychnine and brucine in forensic toxicological laboratories., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Small molecules with rotatable bonds can occupy different conformational states in solution as a consequence of their thermal fluctuations. The accurate determination of the structures of such states, as well as of their statistical weights, has been challenging because of the technical difficulties in extracting information from experimental measurements, which are normally averaged over the conformational space available. Here, to achieve this objective, we present an approach based on a recently proposed tensor-free method for incorporating NMR residual dipolar couplings as structural restraints in replica-averaged molecular dynamics simulations. This approach enables the information provided by the experimental data to be used in the spirit of the maximum entropy principle to determine the structural ensembles of small molecules. Furthermore, in order to enhance the sampling of the conformational space we incorporated the metadynamics method in the simulations. We illustrate the method in the case of strychnine, determining the three major conformational states of this small molecule and their associated occupation probabilities., (Copyright © 2018. Published by Elsevier Inc.)

Bi qi capsule (BQC) is a traditional Chinese medicine prescription that is clinically used for the treatment of rheumatoid arthritis. Strychnine and brucine, as two typical kinds of alkaloids, are the primary active and neurotoxic constituents of BQC. In this study, a sensitive and reliable rapid resolution liquid chromatography-tandem mass spectrometry (RRLC-MS/MS) quantitative method was used to determine the concentrations of brucine and strychnine in rat brain and blood dialysates. The blood-brain barrier (BBB) penetration of free brucine and strychnine and their pharmacokinetic characteristics were investigated by the validated RRLC-MS/MS method coupled with in vivo microdialysis for the first time. The dialysate brain-blood AUC ratios of brucine were 0.098, 0.44 and 0.40 respectively at 0.4, 0.8 and 1.6 g kg -1 doses of BQC, and the dialysate brain-blood AUC ratios of strychnine were 0.20, 1.25 and 2.06 respectively at 0.4, 0.8 and 1.6 g kg -1 doses of BQC. The high brain-blood AUC ratios of brucine and strychnine were observed in medium and high dose groups of BQC. In addition, the effects of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) on brucine and strychnine across BBB were also studied using the above method as well as molecular docking. The results prompted that brucine was the substrate of P-gp, and strychnine might be the inhibitor of P-gp. Brucine and strychnine showed high brain penetration, so it is very important to well control the clinic dosage of BQC and manufactory quality for avoiding the side effects and obtaining good therapeutic efficacy. Our study could be further used in investigating BBB penetration for other drugs caused neurotoxicity., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In this study, we have aimed to analyze the phytochemical composition of this plant and the concentration of strychnine and brucine. The identification of bioactive compounds was done by GC-MS with NIST Library. Strychnine and Brucine were quantified using HPLC. Twenty one medicinal bio active compounds were identified from the Strychnos nux-vomica leaf ethanolic extract. Strychnine is showing 28.43% purity and brucine was not detected in GCMS analysis. Quantified the concentration of strychnine (0.6 mg in 500mg of extract) and brucine (1.6 mg in 500mg of extract) was done by HPLC against Strychnine and Brucine standard. These compounds are having natural properties of Anti-inflammatory, Hypocholesterole, Cancer preventive, Hepatoprotective, Antimicrobial, Antioxidant, Cardio protective, Antiaging, Antialzheimeran, Antidermatitic, Immunostimulant, Anthepatotoxic, biosynthesis of steroid hormones, Nematicide, Antiandrogenic, 5-alpha reductase inhibitor, antipsychotic, analgesic, apoptotic effect, antidepressant, antidote for snake poisoning and diabetic activity.

Many studies have found that some dietary supplement product labels do not accurately reflect the actual ingredients. However, studies have not been performed to determine if ingredients in the same dietary supplement product vary over time. The objective of this study was to assess the consistency of stimulant ingredients in popular sports supplements sold in the United States over a 9-month period. Three samples of nine popular sports supplements were purchased over the 9-month period. The 27 samples were analyzed for caffeine and several other stimulants (including adulterants). The identity and quantity of stimulants were compared with stimulants listed on the label and stimulants found at earlier time points to determine the variability in individual products over the 9-month period. The primary outcome measure was the variability of stimulant amounts in the products examined. Many supplements did not contain the same number and quantity of stimulants at all time points over the 9-month period. Caffeine content varied widely in five of the six caffeinated supplements compared with the initial measurement (-7% to +266%). In addition, the stimulants-synephrine, octopamine, cathine, ephedrine, pseudoephedrine, strychnine, and methylephedrine-occurred in variable amounts in eight of the nine products. The significance of these findings is uncertain: the sample size was insufficient to support statistical analysis. In our sample of nine popular sports supplements, the presence and quantity of stimulants varied over a 9-month period. However, future studies are warranted to determine if the variability found is significant and generalizable to other supplements.

The influence of sample matrix on sample sweeping in MEKC was examined in the presented manuscript. Significant focusing effect was observed for relatively hydrophobic cationic compounds (emetine, strychnine and quinine) using high ionic strength sample matrix (900 mM H3 PO4 /720 mM Tris) which conductivity was about ninefold higher than utilized BGE. Moreover, the results were obtained using BGE composed of comparatively low surfactant concentration (10 mM SDS) and 40 mM H3 PO4 /32 mM Tris buffer solution. About 200 to 300-fold preconcentration of analytes was reached with the presented method. Basing on experimental results and computer simulation using Simul5 software, hypothetical mechanism of observed phenomenon was proposed., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Strychnine is a potent, naturally occurring neurotoxin that effectively protects plants from animal pests by deterring feeding behavior. In insects, such as the fruit fly, Drosophila melanogaster, bitter-tasting aversive compounds are detected primarily through a family of gustatory receptors (GRs), which are expressed in gustatory receptor neurons. We previously described multiple GRs that eliminate the behavioral avoidance to all bitter compounds tested, with the exception of strychnine. Here, we report the identity of a strychnine receptor, referred to as GR47a. We generated a mutation in Gr47a and found that it eliminated strychnine repulsion and strychnine-induced action potentials. GR47a was narrowly tuned, as the responses to other avoidance compounds were unaffected in the mutant animals. This analysis supports an emerging model that Drosophila GRs fall broadly into two specificity classes-one class is comprised of core receptors that are broadly required, whereas the other class, which includes GR47a, consists of narrowly tuned receptors that define chemical specificity., (© The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Strychnine-related death has been described since the 19th century. This alkaloid was discovered in 1818. Historically, strychnine was used by the South-East Asian autochthones on their arrows. However, its production was modified by legislation, which was used to protect people against accidental intoxications. Here, we present the case of a 69-year-old man who was found dead at home. During the autopsy, we found a blue substance in the stomach. Toxicological analysis measured strychnine at 0.29 μg/mL in the blood sample, which is a relatively low level in comparison with the results given in the literature. However, histologic examination and toxicological findings permitted the conclusion of strychnine poisoning., (© 2015 American Academy of Forensic Sciences.)

A novel brucine imprinted polymer was prepared on multi-walled carbon nanotubes by reversible addition-fragmentation chain transfer (RAFT) precipitation polymerization. The polymer was further grafted with hydrophilic poly(glycerol monomethacrylate) brushes to improve its water-compatibility. The obtained molecularly imprinted material showed enhanced accessibility to brucine and improved selective recognition property in water medium. When the material was supported on an ionic liquid functionalized graphene coated glassy carbon electrode for the electrochemical determination of brucine, the resulting electrochemical sensor presented good analytical performance. Under the optimized conditions, the peak current was linear to brucine concentration in the ranges of 0.006-0.6 μM and 0.6-5.0 μM with sensitivities of 15.3 μA/μMmm(2) and 5.4 μA/μM mm(2), respectively; the detection limit was 2 nM (S/N=3). The sensor was successfully applied to the determination of brucine in practical samples and the recovery for the standards added was 94-104%., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A gas chromatography-electron impact-tandem mass spectrometric method was established for the simultaneous determination of seven adulterants, including fenfluramine (FEN), norpseudoephedrine (NPE), pseudoephedrine (PSE), ephedrine (EPH), amfepramone (AMF), sibutramine (SIB) and strychnine (STR) in slimming functional foods. The target chemicals were extracted with 2% formic acid solution and then cleaned-up with solid-phase extraction using a strong cation exchange cartridge from tablet, liquid, mixed plant powder and capsule formulations. Chromatographic separation was accomplished on a VF-5MS column within 23 min. Leucomalachite green was employed as an internal standard. The recoveries of seven target chemicals in two formulations ranged from 80.1 to 106%. Limits of detection of the method were from 7.5 to 375 µg/kg with relative standard deviations of 1.6 to 13.9%. The linearity of the method ranged from 90 to 1500 ng/mL for NPE, 150 to 1500 ng/mL for STR, 10 to 500 ng/mL for AMF, 5.0 to 500 ng/mL for PSE and EPH and 3.0 to 500 ng/mL for FEN and SIB. This method was applied to the determination of six brands of slimming functional foods. SIB was detected in five of the samples with the contents in the range of 10.3 - 8.55 × 10(5) μg/kg.

Objective: To establish a method for determination of strychnine and brucine in formaldehyde fixed tissue by LC-MS/MS analysis., Methods: The samples were pretreated with solid phase extraction using SCX cartridges and separated on SB-C18 column with mobile phase 0.1% formic acid : 0.1% formic acid-acetonitrile (75:25). Electrospray ionization (ESI) source was utilized and operated in positive ion mode. Multiple reactions monitoring (MRM) mode was applied. External standard method was applied for quantitation., Results: The chromatographic separation of strychnine and brucine in formaldehyde fixed nephritic and hepatic tissues resulted successfully. The standard curve was linear in the range of 0.002-2.0 microg/g for strychnine and brucine in formaldehyde fixed tissues, and the correlation coefficient was more than 0.996. The limits of detection (LOD) of strychnine and brucine in nephritic tissues were 0.06ng/g and 0.03 ng/g, respectively. The LOD of both chemicals were 0.3 ng/g in hepatic tissues. The extraction recovery rate was more than 74.5%. The precision of intra-day and inter-day were both less than 8.2%., Conclusion: Strychnine and brucine can be sensitive to be determined in formaldehyde fixed tissue by LC-MS/MS analysis. It can be applied in the forensic toxicological analysis.

A liquid chromatography-electrospray ionization-ion trap mass spectrometry (LC-ESI-ITMS) method was developed for the simultaneous analysis of strychnine, brucine and their major metabolites. Strychnine and brucine were individually incubated with rat liver S9 fraction. The incubation samples were pooled together and analyzed with LC-ESI-ITMS in positive ion and full-scan detection mode. The calibration curves of strychnine and brucine in rat liver showed good linearity in ranges of 0.020 to 8.0 µg/mL for strychnine and 0.020 to 8.5 µg/mL for brucine. The limits of detections were both 0.008 µg/mL and the recoveries were 88.3 and 83.2% for strychnine and brucine, respectively. Two metabolites were identified as strychnine N-oxide and brucine N-oxide by comparing the molecular mass, retention time, full-scan mass spectra, tandem MS and MS(3) spectra with those of strychnine and brucine. The developed method provided high sensitivity and selectivity for the determination of poisonous alkaloids and their major metabolites and can be applied in the determination of samples in forensic and clinically toxicological cases.

Introduction: Strychnos nux-vomica L. (Loganiaceae), widely used in folk medicine, is grown extensively in southern Asian countries. Its major bioactive constituents are strychnine and brucine, which are frequently used in traditional herbal medicines for treatment of nervous diseases, vomiting and traumatic pain., Objective: A new method using a carbon-paste electrode modified with multi-walled carbon nanotubes (CNT/CPE) was developed and validated for single or simultaneous determination of strychnine and brucine in Strychnos nux-vomica seeds. Additionally, an environmentally friendly method was successfully applied to reduce the levels of strychnine and brucine in seeds., Materials and Methods: Cyclic voltammetry, chronocoulometry and differential pulse voltammetry were used with multi-walled carbon nanotube modified carbon-paste electrodes., Results: The peak currents increase linearly with the strychnine and brucine concentrations in the ranges of 50-1000 and 5-355 µ m, and the detection limits for strychnine and brucine were 0.43 and 0.28 µ m, respectively. Of the processing methods used, the greatest reduction in the strychnine and brucine levels was observed in samples processed using milk and saltwater., Conclusion: A new, sensitive and selective method was developed for the measurement of strychnine and brucine. This method was successfully applied to the determination of strychnine and brucine in unprocessed and processed Strychnos nux-vomica seed., (Copyright © 2011 John Wiley & Sons, Ltd.)

Objective: A sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method has been developed and validated for the determination of brucine and strychnine in rat plasma., Method: Samples were extracted by ethyl acetate-n-butanol (7: 3). Chromatographic separation was operated on ZORBAX XDB-C18 column with gradient elution of acetonitrile-methanol-water (0.05% acetic acid and 10 nmol x L(-1) ammonium formate contained), followed by LC-MS/MS in positive electrospray ionization. Quantification was carried out on multiple reaction monitoring (MRM) of the transition m/z 395.2/324.2, m/z 335.2/184.2 and m/z 199.1/171.1 for brucine, strychnine and tacrine (internal standard), respectively., Result: The method was linear in the range of 0.195-100 and 0.07840 microg x L(-1) for brucine and strychnine, with coefficient correlation 0.994 and 0.996 respectively. The recoveries of extraction were 78.9% - 102.4% for brucine and 95.2% - 106.1% for strychnine. Precision, accuracy, stability and matrix effect of the analytes met the requirement. The method was applied to a pharmacokinetic study of brucine and strychnine after cutaneous administration of Semen Strychni niosome gel. The C(max) were (26.20 +/- 5.81) and (12.50 +/- 3.00) microg x L(-1) while the AUC(0-infinity), were (193.75 +/- 39.43) and (98.25 +/- 28.54) microg x h x L(-1) of the two components., Conclusion: We conclude that the niosomes may reduce the systemic exposures and prolong the local release of brucine and strychnine.

Strychnos nux vomica Linn.(Loganaceae) commonly known as Nux vomica (Kupeelu), is a poisonous plant and its seeds are used widely in Ayurvedic system of medicine since time immemorial. Ayurveda advocates that nux vomica seeds are to be administered in therapeutics only after going through certain purificatory measures (Shodhana). There are more than six media: cow's urine (Go mutra), cow's milk (Go dugdha), cow's ghee (Go ghrita), Kanji (thin gruel), castor oil (Eranda taila) and fresh ginger juice (Ardraka swarasa) etc., which have been reported in different classical texts of Ayurveda for proper processing of nux vomica seeds. In this study, an attempt has been made to purify the seeds by using three different methods as described in ancient treatise by using cow's urine and cow's milk as media alone and together. This study revealed that all the methods studied reduced the toxicity of strychnine and brucine contents in comparison to the raw seeds as determined by HPTLC. Out of these three methods maximum reduction in strychnine and brucine contents was found when the seeds were purified by keeping them in cow's urine for seven days followed by boiling in cow's milk for three hrs.

Various experimental methods have been developed to unequivocally identify vicinal neighbor carbon atoms. Variants of the HMBC experiment intended for this purpose have included 2J3J-HMBC and H2BC. The 1,1-ADEQUATE experiment, in contrast, was developed to accomplish the same goal but relies on the (1) J(CC) coupling between a proton-carbon resonant pair and the adjacent neighbor carbon. Hence, 1,1-ADEQUATE can identify non-protonated adjacent neighbor carbons, whereas the 2J3J-HMBC and H2BC experiments require both neighbor carbons to be protonated to operate. Since 1,1-ADEQUATE data are normally interpreted with close reference to an HSQC spectrum of the molecule in question, we were interested in exploring the unsymmetrical indirect covariance processing of multiplicity-edited GHSQC and 1,1-ADEQUATE spectra to afford an HSQC-ADEQUATE correlation spectrum that facilitates the extraction of carbon-carbon connectivity information. The HSQC-ADEQUATE spectrum of strychnine is shown and the means by which the carbon skeleton can be conveniently traced is discussed., (Copyright © 2011 John Wiley & Sons, Ltd.)

The successful measurement of anisotropic NMR parameters like residual dipolar couplings (RDCs), residual quadrupolar couplings (RQCs), or residual chemical shift anisotropy (RCSA) involves the partial alignment of solute molecules in an alignment medium. To avoid any influence of the change of environment from the isotropic to the anisotropic sample, the measurement of both datasets with a single sample is highly desirable. Here, we introduce the scaling of alignment for mechanically stretched polymer gels by varying the angle of the director of alignment relative to the static magnetic field, which we call variable angle NMR spectroscopy (VA-NMR). The technique is closely related to variable angle sample spinning NMR spectroscopy (VASS-NMR) of liquid crystalline samples, but due to the mechanical fixation of the director of alignment no sample spinning is necessary. Also, in contrast to VASS-NMR, VA-NMR works for the full range of sample inclinations between 0° and 90°. Isotropic spectra are obtained at the magic angle. As a demonstration of the approach we measure ¹³C-RCSA values for strychnine in a stretched PDMS/CDCl₃ gel and show their usefulness for assignment purposes. In this context special care has been taken with respect to the exact calibration of chemical shift data, for which three approaches have been derived and tested., (Copyright © 2010 Elsevier Inc. All rights reserved.)

The accuracy inherent in the measurement of interproton distances in small molecules by nuclear Overhauser enhancement (NOE) and rotational Overhauser enhancement (ROE) methods is investigated with the rigid model compound strychnine. The results suggest that interproton distances can be established with a remarkable level of accuracy, within a few percent of their true values, using a straight-forward data analysis method if experiments are conducted under conditions that support the initial rate approximation. Dealing with deviations from these conditions and other practical issues regarding these measurements are discussed.

A simple and low-cost HPLC method with UV absorbance detection was developed and validated to simultaneously determine strychnine and brucine, the most abundant alkaloids in the processed Semen Strychni, in rat tissues (kidney, liver, spleen, lung, heart, stomach, small intestine, brain and plasma). The tissue samples were treated with a simple liquid-liquid extraction prior to HPLC. The LOQs were in the range of 0.039-0.050 µg/ml for different tissue or plasma samples. The extraction recoveries varied from 71.63 to 98.79%. The linear range was 0.05-2 µg/ml with correlation coefficient of over 0.991. The intra- and inter-day precision was less than 15%. Then the method was used to measure the tissue distribution of strychnine and brucine after intravenous administration of 1 mg/kg crude alkaloids fraction (CAF) extracted from the processed Semen Strychni. The results revealed that strychnine and brucine possessed similar tissue distribution characterization. The highest level was observed in kidney, while the lowest level was found in brain. It was indicated that kidney might be the primary excretion organ of prototype strychnine and brucine. It was also deduced that strychnine and brucine had difficulty in crossing the blood-brain barrier. Furthermore, no long-term accumulation of strychnine and brucine was found in rat tissues.

Background: Brucine, the major active alkaloid constituent extracted from traditional Chinese herbal medicine Nux vomica, had been found to possess remarkable antitumor, analgesic, and anti-inflammatory activities. In this study, we attempted to encapsulate brucine into liposomes to improve its therapeutic effects. The entrapment efficiency (EE) and the stability of liposomes are two key factors associated with the therapeutic effects of liposomal drugs. We developed a novel liposome-based brucine formulation that was composed of soybean phosphatidylcholine (SPC) and hydrogenated soybean phosphatidylcholine (HSPC)., Method: The liposomes with different phospholipid composition were characterized for their EE, vesicle size, drug release profile, and leakage in vitro., Results: The molar ratio of HSPC/SPC = 1:9 was determined as the optimum ratio. Compared with conventional liposomes composed of only SPC or HSPC, EE of the brucine-loaded novel liposomes was increased markedly, especially at high drug/lipid molar ratios. The results of drug release showed that the novel liposomes were more stable than the conventional SPC liposomes in the presence of fetal calf serum. In addition, the results of the leakage experiments revealed that the novel liposomes also had better stability in phosphate buffer solution (PBS) with respect to drug retention. Although the conventional HSPC liposomes is more stable than the novel liposomes, the novel liposomes composed of 10% HSPC and 90% SPC may still have promising application potential because HSPC is much more expensive than SPC., Conclusion: Taken together, efficient encapsulation of brucine into the novel liposomes, their improved stability, and the price of phospholipids indicate that the novel liposomes may act as promising carriers for active alkaloids such as brucine.

Nicotine, a lipid-soluble alkaloid obtained from the dried leaves of Nicotiana, is most frequently encountered in tobacco products for smoking, chewing or sniffing as well as in a limited number of pesticides. Though nicotine is one of the most toxic drugs of abuse, it has rarely led to fatalities. Sudden death can be caused by cardiovascular arrest, respiratory muscle paralysis and/or central respiratory failure. A 42-year-old man was found dead by his wife. He was lying on the floor, next to a box containing many empty bottles of beer and vodka. Some labeled chemical bottles found at the scene contained various substances, including nicotine and brucine. Gross examination of the organs at autopsy revealed no specific findings. The toxicological examination failed to disclose any lethal toxic agents other than a high concentration of nicotine and its primary metabolite cotinine in femoral venous blood (2.2 microg/mL). Blood alcohol was determined to be 2.1 g/L in femoral venous blood. Only a paucity of fatal cases of nicotine poisoning has been reported in the literature so far., (2009 Elsevier Ireland Ltd. All rights reserved.)

Objective: To establish the fingerprint of Semen Strychni and the processed by HPLC., Methods: The HPLC Method was used, the chromatgraphic conditions were as follows: Chromatographic column: Lichrospher C18 (250 mm x 4.6 mm, 5 microm), mobile phase: solvent A consisted of water-ethanoic acid-triethylamine (100: 0.2: 0.2), solvent B contained acetonitril (gradient elution), column temperature: 30 degrees C, flow rate: 1.0 mL/min, detection wavelength: 254 nm., Results: The similar degree of 10 batch samples buiding sharing mode of crude drug and processed product was above 0.9. 18 common peaks in chromatograms were separated from 10 batches of Semen Strychni samples and 21 common peaks in chromatograms were separated from 10 batches of the processed., Conclusion: This study establishes the HPLC fingerprint commonmode, and researches the difference between Semen Strychni and the processed in HPLC fingerprint.

J-resolved NMR spectroscopy is a well-established method for measuring coupling constants or enhancing the resolution in homonuclear experiments. Classical J-spectra typically suffer from inevitable dispersive signal contributions and the occurrence of "ghost peaks" due to strong coupling effects. In this article, a J-resolved-type experiment with an adiabatic z-filter element for the selection of inphase magnetization and quadrature detection in the indirect dimension is presented. The phase-sensitive recording scheme allows the distinction of strong coupling artefacts from symmetry relations and the full multiplet obtained by the experiment can be reduced by a simple pattern recognition algorithm. In addition to the J-resolved experiment, a second experiment is introduced that correlates strongly coupled spins. The possibility of homonuclear decoupling using the J-resolved experiment with the pattern recognition algorithm is demonstrated on a number of samples with a detailed description of potential strong coupling artefacts.

Multiple myeloma (MM) is an incurable hematological malignancy with high incidence in the elderly. The currently used chemotherapeutic drugs show severe side effects, dose-limiting toxicity and development of resistance. In search of novel plant derived anti-cancer agents, Strychnos nux-vomica L. (SN) root extract was screened using the human MM-cell line, RPMI 8226. SN-extract exhibited anti-proliferative activity in a dose and time dependent manner. The morphological assessment of SN-extract treated cells showed significant features associated with apoptosis. Cell cycle analysis using flow cytometry of cells stained with propidium iodide revealed accumulation of cells at sub-G(0)/G(1) phase. In addition, disruption of mitochondrial membrane potential and subsequent leakage of mitochondrial cytochrome c was observed in SN-extract treated myeloma cells. The anti-proliferative and cytotoxic activity could be due to the alkaloids strychnine and brucine, which have been identified by LC-mass spectral analysis of the SN-extract in comparison to the reference standards analyzed under identical conditions.

Implementation of an uncomplicated SPE process for the rapid extraction and preconcentration of the alkaloids, colchicine, strychnine, aconitine, and nicotine, from water, apple juice, and nonfat milk samples is presented. When coupled to analysis via micellar EKC (MEKC), the total analysis time per sample was less than 15 min for the water and juice samples and less than 20 min for the milk. The SPE process allowed for anywhere from a three to a fourteen-fold improvement in the LOD for each alkaloid when compared to detecting the alkaloids in a nontreated water sample matrix. Following SPE, the LODs for colchicine, strychnine, and nicotine were sufficient to meet levels from 150 to 5000 times more dilute than the LD(50) for a 50 kg individual drinking 12 oz of a contaminated beverage. Aconitine, on the other hand, was detected at approximately the LD(50) level. The percent recoveries for the SPE ranged from 37% to as high as 99%. Nicotine attained the highest recovery efficiencies, followed by colchicine, and finally, aconitine and strychnine, which were nearly identical. The greatest recovery efficiencies were achieved from apple juice and water, whereas nonfat milk yielded the lowest.

A microchip device is demonstrated for the electrophoretic separation and UV-absorbance spectral detection of four toxic alkaloids: colchicine, aconitine, strychnine, and nicotine. A fused-silica (quartz) microchip containing a simple cross geometry is utilized to perform the separations, and a miniature, fiber-optic CCD spectrometer is coupled to the microchip for detection. Sensitive UV-absorbance detection is achieved via the application of online preconcentration techniques in combination with the quartz microchip substrate which contains an etched bubble-cell for increased pathlength. The miniature CCD spectrometer is configured to detect light between 190 and 645 nm and LabView programming written in-house enables absorbance spectra as well as separations to be monitored from 210 to 400 nm. Consequently, the configuration of this microchip device facilitates qualitative and quantitative separations via simultaneous spatial and spectral resolution of solutes. UV-absorbance limits of quantification for colchicine, 20 microM (8 mg/L); strychnine, 50 microM (17 mg/L); aconitine, 50 microM (32 mg/L); and nicotine, 100 microM (16 mg/L) are demonstrated on the microchip. With the exception of aconitine, these concentrations are > or =20-times more sensitive than lethal dose monitoring requirements. Finally, this device is demonstrated to successfully detect each toxin in water, skim milk, and apple juice samples spiked at sublethal dose concentrations after a simple, SPE procedure.

A simple, sensitive, and specific thin-layer chromatography densitometric method has been developed for the simultaneous quantitation of strychnine and brucine. These two marker compounds are quantitated in the seeds of Strychnos nux-vomica, Strychnos ignatii, and its formulations. The method involves densitometric evaluation of strychnine and brucine after resolving it by high-performance TLC on silica gel plate with toluene-ethyl acetate-diethyl amine-methanol (7:2:1:0.3 v/v) as the mobile phase. The method is validated for precision (interday and intraday), repeatability, and accuracy. The relationship between the concentration of standard solutions and the peak response is linear within the concentration range of 160 to 480 ng/spot for strychnine and 80 to 480 ng/spot for brucine. Instrumental precision is found to be 0.54 and 0.78 (% CV), and repeatability of the method is 1.01 and 1.06 (% CV) for strychnine and brucine, respectively. Accuracy of the method is checked by recovery study conducted at three different levels and the average percentage recovery is found to be 99.13% for strychnine and 100.16% for brucine. The proposed HPTLC method for the simultaneous quantitation of strychnine and brucine is found to be simple, precise, specific, sensitive, and accurate, and it can be used for routine quality control of raw material of Strychnos spp. It also can be applied in quantitating any of these marker compounds in other formulations.

The toxic nitrogen alkaloids nicotine, strychnine, and aconitine were quantitated in whole milk, skim milk, and cream using solid-phase extraction cleanup and HPLC-UV with dual wavelength detection. Samples were extracted in McIlvaine's buffer with EDTA and then partitioned with aqueous acetonitrile and hexane. The aqueous phase was concentrated and passed through an OASIS HLB column. The column was eluted with methylene chloride/ammonium hydroxide, 1 mL/1 microL, v/v. The eluent was acidified with hydrochloric acid and evaporated. The sample was diluted for HPLC with acetonitrile/phosphate buffer pH 7.4. Chromatography was performed on an Xterra RP-18 column using a gradient of acetonitrile and ammonium bicarbonate buffer at pH 9.8. Nicotine and strychnine were monitored at 260 nm; aconitine was monitored at 232 nm. Calibration curves were generated from external standards in the range 0.2-10 microg/mL using 1/x weighting. Mean recoveries in whole milk spiked between 0.1 and 10 ppm were the following: nicotine 89.2%, strychnine 75.7%, and aconitine 85.1%. Mean recoveries in skim milk spiked between 0.1 and 10 ppm were the following: nicotine 72.1%, strychnine 78.2%, and aconitine 82.9%. Mean recoveries in cream spiked between 0.2 and 20 ppm were the following: nicotine 87.9%, strychnine 76.9%, and aconitine 82.0%. Relative standard deviations of recovery were less than 20% in each case.

An easy, rapid method for simultaneous determination of strychnine and brucine in Strychnos nux-vomica L. and its preparation was developed by nonaqueous capillary electrophoresis (NACE) without pretreatment for the first time. Optimum separation was achieved with a fused-silica capillary column (50 cmx75 microm i.d.) and a running buffer containing 30 mM ammonium acetate, 1.0% acetic acid and 15% acetonitrile (ACN) in methanol medium. The applied voltage was 30.0 kV. The analytes were detected by UV at 214 nm. The effects of concentration of ammonium acetate, acetic acid and organic modifier on electrophoretic behavior of the analytes were studied. The established method with sophoridine as internal standard was linear in the range of 5-1000 mg/mL for both strychnine and brucine. The extracts of Strychnos nux-vomica and its preparation could be directly injected for determination with recoveries ranging from 94.5 to 104%.

Two quality control methods of nuxvomica were established for mutual. By selecting the appropriate measuring wavelength or wavelength range, the contents of strychnine and brucine in nuxvomica were determined without any preliminary separation by a new rapid spectrophotometry and a multi-wavelength linear regression spectrophotometry and with a computer program. The linear range of strychnine measured was 8.0-30.0 microg x mL(-1) (r = 0.999 9); The linear range of brucine measured was 7.0-31.2 microg x mL(-1) (r = 0.999 4). The average recoveries and relative standard deviations of strychnine and brucine were 98.18%-99.82%, 0.56%-1.54% and 100.5%-100.6%, 0.57%-0.62%, respectively. The methods are simple, rapid and reproducible, the interference of two components with each other may be eliminated and the methods are appropriate for quality control of nuxvomica.

The fragmentations of four strychnos alkaloids have been investigated by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) in the positive ion mode. Experiments using multi-stage tandem mass spectrometry (ESI-FT-ICR-MSn) allowed us to obtain precise elemental compositions of product ions at high mass resolution. The experimental data demonstrated that the nitrogen bridge and the coordinated oxygen atom on the nitrogen bridge in the alkaloid compounds were the active sites in the MS2 fragmentations. The loss of CH3 or the OCH3 group in those alkaloids, which have an OCH3 substituent, was the dominant fragmentation mode in the MS3 fragmentations. Logical fragmentation schemes for strychnos alkaloids have been proposed and these should be useful for the identification of these compounds., (Copyright 2006 John Wiley & Sons, Ltd.)

A method has been developed for rapidly separating and detecting strychnine and brucine using a poly(dimethysiloxane) (PDMS) microchip and electrochemical (EC) detection. PDMS microchannels dynamically modified by Brij35 are shown to be more efficient than native ones. The two analytes are well separated within 90 s in 70 mmol/L acetate buffer (pH 5.5) containing 0.01% (v/v) Brij35. Detection limits were found to be 1.0 micromol/L for strychnine and 0.2 micromol/L for brucine at S/N = 3. The method was used to determine trace strychnine and brucine in rat serum, and the results obtained correlate well with those obtained via high-performance liquid chromatography (HPLC).

Objective: To establish a new method for determination of strychnine alkaloid in biological fluids based on molecularly imprinted polymers., Methods: A strychnine molecularly imprinted monolithic column was prepared by in-situ molecularly imprinted technique. The polymer was filled to a 1cm column, and a method was developed to concentrate and determine strychnine alkaloids in biological fluids., Results: the limit of detection of the method was 4.9 ng, and the recoveries were more than 92%. The relative standard deviations were smaller than 6.59%. The linear correlation coefficients of standard curves were 0.999 1 and 0.9966 respectively. This method was applied to concentrate and determine strychnine in plasma and urine of poisoned rabbit., Conclusion: The new method could concentrate and simultaneously determine strychnine alkaloids in biological fluids, and it was applied to forensic toxicological analysis.

4-Amino-2-mercaptopyrimidine self-assembled monolayer (AMP SAMs/Au) was prepared on a gold electrode. The AMP SAMs/Au was characterized by using attenuated total reflection-fourier transform infrared (ATR-FTIR) and A.C. Impedance. The electrochemical behavior of brucine on AMP SAMs/Au was studied by cyclic voltammetry (CV) and square wave adsorptive stripping voltammetry (SWASV). The modified electrode showed an excellent electrocatalytic activity for the redox of brucine. The catalytic current increased linearly with the concentration of brucine in the range of 4.0 x 10(-7) to 2.0 x 10(-4) mol l(-1) by square wave voltammetry response. The detection limit was 6.0 x 10(-8) mol l(-1).

A high performance liquid chromatography/mass spectrometry (HPLC/MS) method was developed in support of a study to assess potential tertiary risks posed to insectivores by strychnine baited pocket gophers (Thomomys sp.). Necropholous insects are primary consumers of pocket gopher carcasses. A field study was conducted to collect insects from strychnine-baited and control pocket gopher carcasses. The majority of the insects collected were from the orders Diptera (flies, assayed separately as adults and larvae), Coleoptera (beetles), and Hymenoptera (ants and wasps, assayed separately). Samples (0.5 g) were extracted in acetic acid (2%) and analyzed with the mass spectrometer configured for tandem mass spectrometry. For most of the samples the strychnine concentrations were less than the method limit of detection. However, strychnine concentrations as high as 0.338, 0.341, 0.698, and 0.034 microg/g were detected in ants, fly adults, fly larvae, and beetles, respectively. This information collected with the HPLC/MS method is critical for assessing potential non-target hazards for insectivores.

It is widely acknowledged that there is a critical need for broad-spectrum environmental threat detection. While cells/tissue-based biosensors have been discussed for many years as a means of meeting this critical need, these kinds of systems have met with logistic concerns, in particular with regard to stability. Our group has been working with cultured neuronal networks, which have the capacity to respond to a wide range of neuroactive compounds and are sufficiently robust to be shipped to end users. The basis of operation involves extracellular recording using thin-film microelectrode arrays where spontaneous bioelectrical activity, that is, spike firing, can be monitored in a noninvasive manner conducive for potentially long-term measurements. This work describes the current status of our efforts for the fabrication of a portable biosensor that incorporates cultured neuronal networks grown over standardized microelectrode arrays. Based on our protocol for aqueous phase sample introduction under constant flow conditions, minimal variation in mean spike rate is observed, consistent with temporal stability, such that changes of > 10% are readily distinguished. To demonstrate the capability of this system, changes are reported in mean spike rate and network synchronization resulting from exposure to different model environmental threats, cadmium and strychnine. The sensitivity of this assay approach and implications of the experimental findings for environmental threat detection are discussed.

A sensitive method for the identification and quantitation of the toxic alkaloids strychnine and brucine from postmortem specimens has been established. After solid-phase extraction using Oasis MCX cartridges the extracts were analyzed by high-performance liquid chromatography with diode-array detection. The limit of detection was 0.5 ng/mL blood for strychnine and brucine, and the limit of quantitation was 5 ng/mL blood for strychnine and brucine. The method was applied for the analysis of blood and gastric contents of a 34-year-old female who died after ingestion of a packet of herbal medicine powder containing the seeds of Strychnos nux-vomica L. Strychnine and brucine were detected in all the samples. The concentration in our case is consistent with that in previous reports.

A new capillary electrophoresis procedure with field-enhanced stacking concentration for the analysis of strychnine and brucine is established. After optimization of the separation and concentration conditions, the two alkaloids can be separated within 5 min and quantified with high sensitivity (The detection limits were 1.0 ng mL(-1) for strychnine and 1.4 ng mL(-1) for brucine). The method was useful for qualitative and quantitative analysis of strychnine and brucine in Strychnos nux-vomica L with recovery of 105.1% for strychnine and 98.4% for brucine.

Objective: This paper reports a HPLC method for determinition of strychnine and brucine in Semen Strychni and its processed products of Jiangxi method and innovated methed., Method: SiO2 was used as the stationary phase, n-hexane-dichloromethane-methanol-ammonia(47.5:47.5:5:0.35) as the mobile phase, with detection wavelength of 254 nm., Result: The contents of strychnine and brucine in the processed products of Jiangxi are lower., Conclusion: This method is accurate, simple and reliable.

A simple and rapid method for the determination of berberine and strychnine in medicinal plants and herbal preparations for regulatory purposes using a home-made pressurized liquid extraction (PLE) system with capillary zone electrophoresis (CZE) using ultraviolet detection at 254 nm was developed. The effects of pH, concentration of buffer, and organic modifiers in the electrophoretic separation were investigated. The buffer used for CZE contained 50 mM ammonium acetate, pH 3.1. The effect of temperature on the extraction efficiency of strychnine in medicinal plants by PLE was demonstrated. Comparable or higher extraction efficiency was achieved with PLE for strychnine in medicinal plants and berberine in herbal preparations compared to soxhlet extraction. The effect of matrix interference in medicinal plants and herbal preparations containing a number of medicinal plants samples using CZE was investigated by standard additional experiments. The reproducibility of the method using PLE with CZE was found to vary between 2.4 and 10.7% (n = 5/6) for different types of samples on different days.

A non-fatal case of strychnine poisoning through dermal exposure is described. About 24 h after cleaning up a strychnine spill, a 50-year-old woman presented to the emergency department with classical signs of strychnine poisoning, consisting of marked pain in the muscles of her lower limbs, dermal sensitivity, and stiffness in her jaw. Her treatment was intravenous fluid replacement and alkalinization in anticipation of potential renal failure due to rhabdomyolysis. Her plasma creatine kinase was elevated to 677 U/L with no rise in the heart specific MB fraction. Serum myoglobin level obtained retrospectively was 195 microg/L. Biological samples were taken approximately 28 h after her exposure. Strychnine was measured in plasma (196 ng/mL) and urine (6,850 ng/mL) by gas chromatography-mass spectrometry. The small amount of pheniramine in the plasma (35 ng/mL) and urine (1,255 ng/mL) is considered an inconsequential finding.

A capillary zone electrophoresis method was developed for the separation and determination of strychnine and brucine in Strychnos nux-vomica L. and its preparation. The factors that could affect the separation were studied, such as the types and concentrations of electrolytes, pH, ionic strength and organic modifier. The optimum running buffer was 20 mmol/L of ammonium acetate containing 0.2 mol/L of glacial acetic acid (pH 3.64). The applied voltage was 25 kV and the wavelength of the UV detector was set at 214 nm. The established method with dopamine hydrochloride as internal standard was linear in the range of 5-100 microg/mL for both strychnine and brucine. The recovery was 102.96% for strychnine and 98.56% for brucine. The extracts of Strychnos nux-vomica and its preparation could be directly injected for analysis., (Copyright 2000 John Wiley & Sons, Ltd.)

An HPLC method for the determination of brucine in seed dressing agents was investigated. The sample solution was separated on a Spherisorb C18 column(4.6 mm i.d. x 200 mm, 5 microns) with CH3OH-H2O-CTAB (88:12:0.04, m/m) as the mobile phase and detected at 254 nm. Calibration curve of brucine was obtained for the concentration range of 0.01 g/L-0.25 g/L. The linear regression equation was A = 11,485,814 rho + 21,229, r = 0.9997. The RSD was 1.2%(n = 11). The results show that this method is simple, specific and accurate.

This paper describes an analytical method for strychnine determination in biological samples by gas chromatography/mass spectrometry and their application in the investigation of two cases involving strychnine ingestion: A fatal case and a clinical one. The strychnine is isolated from biological samples using a liquid-liquid extraction procedure. The clean-up procedure is performed using an acid solution. Papaverine is used as internal standard in the quantification of strychnine. In the analysed specimens, the limits of quantification were 0.1 microg/ml or 0.1 microg/g. The recovery rate ranged from 75.0% to 98.7% and the coefficients of variation ranged from 4.8% to 10.5%.

The identification and quantitation of atropine, in whole blood and gastric contents in the presence of strychnine and tetracaine is described. This method uses liquid-liquid extraction and micellar electrokinetic chromatography (MECC). Separations are made using a 50 cm long capillary and a borate/phosphate buffer at pH 9.2 with 50 mM sodium dodecyl sulfate (SDS). Linearity was established for the three compounds between 1.0 and 100 microg/mL, using scopolamine as internal standard. The limit of detection for atropine was estimated at 0.06 microg/mL and the limit of quantitation at 0.2 microg/mL. The run time is less than 30 min. Alternate parameters are proposed to reduce the run time to under 10 min. The method was applied to a forensic post-mortem case.

Determination has been made on the contents of strychnine, brucine and ephedrin in different processed products of Strychnos nux-vomica. The acute toxicity, analgesic and antiphlogistic actions of these products have also been detected. The result shows that the product processed with Ephedra sinica can reduce toxicity and promote curative effect. Among the different processing methods the preparation with Ephedra and Liqorice root and the preparation with Ephedra and alcohol appear better and thus useful in practical application.

This paper describes the determination of strychnine and brucine in the seeds, root, stem and leaves of Strychnos species by HPLC. The analytical column used was ZY110 YNG-C18. The mobile phase was KH2PO4(0.01 mol.L-1)--MeOH(73:27), pH2.5, regulated by 10% H3PO4. Flow rate was 1.0 ml.min-1. The detection wavelength was 264 nm. The linear ranges of strychmine and brucine were 0.18-7.26 micrograms and 0.11-4.32 micrograms, respectively. The recoveries of strychnine and brucine were 98.27% and 98.04%, respectively. The analytical results showed that the contents of strychnine and brucine in samples showed great difference between different species. The contents of strychnine in the seeds of Strychnos wallichiana and S. ignatii were 5.6% and 3.9%, respectively. These results show that the two Strychnos species may be developed as the resources of strychnine.

Homicide by strychnine has become very rare during the last decades. Its bitter taste and the violent mode of death commonly aroused suspicion of poisoning and this, together with its ease of chemical detection, deterred criminals from using it. We present the case of an elderly woman who arrived at the hospital casualty department in extremis and with severe convulsions. Her death was certified nevertheless as due to natural causes and she was buried without the death being reported to the Director of Public Prosecutions. It was not until a month later that investigation led to the exhumation of the body. Biological samples were found to contain strychnine sulphate. The perpetrator was charged and later confessed.