Strong Column Research Articles

Critical buckling load optimization of the axially graded layered uniform columns

This study presents critical buckling load optimization of the axially graded layered uniform columns. In the first place, characteristic equations for the critical buckling loads for all boundary conditions are obtained using the transfer matrix method. Then, for each case, square of this equation is taken as a fitness function together with constraints. Due to explicitly unavailable objective function for the critical buckling loads as a function of segment length and volume fraction of the materials, especially for the column structures with higher segment numbers, initially, prescribed value is assumed for it and then the design variables satisfying constraints are searched using Differential Evolution (DE) optimization method coupled with eigen-value routine. For constraint handling, Exterior Penalty Function formulation is adapted to the optimization cycle. Different boundary conditions are considered. The results reveal that maximum increments in the critical buckling loads are attained about 20% for cantilevered and pinned-pinned end conditions and 18% for clamped-clamped case. Finally, the strongest column structure configurations will be determined. The scientific and statistical results confirmed efficiency, reliability and robustness of the Differential Evolution optimization method and it can be used in the similar problems which especially include transcendental functions.

Optimum buckling design of axially layered graded uniform columns

Abstract This study presents optimum buckling design of axially layered graded uniform columns. Firstly, characteristic equations for determining critical buckling loads for all end conditions are obtained using the transfer matrix method and for each case, square of this equation is selected as a fitness function. Due to the explicitly unavailable objective function for the critical buckling loads as a function of volume fraction and length of the column, initially, prescribed value is assumed for it and then the design variables satisfying constraints are determined. Different boundary conditions are considered. Among them, maximum increment up to 19 % of the critical buckling load is attained for the simply supported case. Finally, the strongest column configurations are determined.

Nonlinear seismic responses and lateral force transfer mechanisms of RC frames with different infill configurations

Due to the architectural efficiency of masonry-infilled reinforced concrete frames, the frames are highly common structural forms for buildings. However, the infills can significantly modify the structural behaviour of these frames, which can be detrimental to the seismic performance of buildings. This study investigates the seismic response and failure mechanisms of infilled RC-frame structures with five different infill configurations: (1) full infills, (2) 2/3-storey-height infills, (3) a soft first storey, (4) infills with window openings and (5) infills with door openings. The nonlinear response history behaviour of the masonry-infilled RC frames under four realistic earthquakes, namely, the 1979 El Centro, 1987 Superstition Hills, 1995 Kobe and 1999 Chi-Chi earthquakes, were simulated using discrete-finite element analysis with damage-based constitutive relations. The analysis indicated that the degrees of continuity and regularity of the infill panels crucially affect the seismic performance of structures. As long as out-of-plane collapse of infills does not occur, full-height and continuous-infill panels can enhance the overall stability and energy dissipation of frame structures. By contrast, discontinuous infills can inflict serious damage localised at the points of discontinuity in the frame members. Furthermore, the analysis revealed that the design concept of “strong column–weak beam” may not be always applicable to infilled frames.

Seismic behavior of frames with innovative energy dissipation systems (FUSEIS1-2)

Modern seismic codes allow for inelastic deformations in dissipative zones during design earthquakes, accepting damage to a certain extent in the relevant structural parts. In the frame of a European Research Program “FUSEIS” two innovative seismic resistant systems were introduced and relevant design guides developed. The first system, named FUSEIS1, consists of a pair of closely spaced strong columns joined together by a number of fuses. This system is further subdivided in FUSEIS1-1 where the dissipative fuses are beams and in FUSEIS1-2 where the fuses are short pins. This paper reports on the seismic performance of buildings with FUSEIS1-2 systems. It discusses results of nonlinear static and dynamic analyses that were based on element properties as derived by the tests and provides design recommendations and appropriate behavior factors. The results confirm the good seismic performance of the system under seismic loading and its capacity to develop self-centering properties under certain conditions.

Field investigation on severely damaged aseismic buildings in 2014 Ludian earthquake

The 2014 magnitude 6.5 Ludian earthquake caused a death toll of 617, many landslides and tens of thousands of collapsed buildings. A field investigation to evaluate the damage to buildings was carried out immediately after the occurrence of the earthquake. Severely damaged aseismic buildings, which were basically observed in the downtown of Longtoushan Town, were carefully examined one by one with the aim to improve design codes. This paper summarizes the damage observed to the investigated aseismic buildings in both the structural and local levels. A common failure mode was observed that most of the aseismic buildings, such as RC frame structures and confined masonry structures, were similarly destroyed by severe damage or complete collapse of the first story. The related strong ground motion, which was recorded at the nearby station, had a short duration of less than 20 s but a very large PGA up to 1.0 g. The RC frames based on the new design codes still failed to achieve the design target for “strong column, weak beam”. Typical local failure details, which were related to the interaction between RC columns and infill walls and between constructional columns and masonry walls, are summarized with preliminary analyses.

Structural and Functional Study of d-Glucuronyl C5-epimerase

Heparan sulfate (HS) is a glycosaminoglycan present on the cell surface and in the extracellular matrix, which interacts with diverse signal molecules and is essential for many physiological processes including embryonic development, cell growth, inflammation, and blood coagulation. D-glucuronyl C5-epimerase (Glce) is a crucial enzyme in HS synthesis, converting D-glucuronic acid to L-iduronic acid to increase HS flexibility. This modification of HS is important for protein ligand recognition. We have determined the crystal structures of Glce in apo-form (unliganded) and in complex with heparin hexasaccharide (product of Glce following O-sulfation), both in a stable dimer conformation. A Glce dimer contains two catalytic sites, each at a positively charged cleft in C-terminal α-helical domains binding one negatively charged hexasaccharide. Based on the structural and mutagenesis studies, three tyrosine residues, Tyr(468), Tyr(528), and Tyr(546), in the active site were found to be crucial for the enzymatic activity. The complex structure also reveals the mechanism of product inhibition (i.e. 2-O- and 6-O-sulfation of HS keeps the C5 carbon of L-iduronic acid away from the active-site tyrosine residues). Our structural and functional data advance understanding of the key modification in HS biosynthesis.

Особливості тотальної артропластики при диспластичному коксартрозі

Диспластичний коксартроз належить до найбільш тяжких уражень опорно-рухової системи. На відміну від ідіопатичного та післятравматичного артрозо-артриту це зумовлене насамперед не проявами деструктивно-дистрофічного процесу в кульшовому суглобі, а різноманіттям і складністю прогресуючих анатомо-фізіологічних змін опорно-рухового апарату. Більшість пацієнтів — молоді люди працездатного віку, які через функціональні обмеження стають інвалідами. На цій стадії захворювання тотальна артропластика кульшового суглоба визнається безальтернативним хірургічним утручанням, що дозволяє відновити опорно-рухову функцію.У науковому й практичному аспектах головним завданням численних досліджень є максимальне відновлення опорно-рухової функції або компенсація біомеханічних порушень, а також забезпечення умов для тривалого збереження стабільності імплантату (компонентів ендопротеза) у тазовій кістці й проксимальному відділі стегнової кістки.Мета роботи — аналіз факторів, що визначають вибір хірургічної тактики й особливості первинної тотальної артропластики при диспластичному коксартрозі.До ретроспективного аналізу включено 157 пацієнтів, серед яких було 148 жінок і 9 чоловіків віком від 19 до 56 років (середній вік 37,4 ± 3,2 року). За даними рентгенографії, 93 (59,2 %) пацієнти мали ураження обох кульшових суглобів. Загальна кількість операцій первинної артропластики — 193 (100 %), у тому числі 36 (18,7 %) на обох кульшових суглобах. Планування лікувальної тактики проводили на підставі результатів рентгенографічного дослідження і спіральної комп’ютерної томографії. Отримані результати були систематизовані за ступенем проксимальної дислокації стегна (Crowe et al., 1979), а також за проявами патологічних змін вертлюжної западини відповідно до класифікації Hartofilakidis et al. (1996).Визначено головні моменти, які впливають на вибір хірургічної тактики, визначають особливості хірургічних утручань: недорозвиненість і навіть відсутність склепіння, недорозвиненість задньої і, особливо, передньої стінки, зменшення глибини западини з потоншенням медіальної стінки, порушене співвідношення диспластичної вертлюжної западини й головки стегнової кістки, деформація проксимального відділу стегна, наявність двобічного ураження кульшових суглобів, деформація тазового кільця, сколіотична деформація хребта, дисбаланс і слабкість м’язів тазового поясу, а також супутні деформації кінцівки диспластичного генезу.Розташування чашки ендопротеза відповідно до фізіологічних параметрів має забезпечити відновлення природного центру обертання кульшового суглоба, офсету й балансу м’язів. У випадках занадто малої й тонкої передньої стінки необхідно зберегти її субхондральну кортикальну пластинку. Кісткове ложе для чашки рекомендуємо формувати римерами, переважно за рахунок більш міцної й масивної задньої колони. При центральних дефектах медіальної стінки западини виконували кісткову пластику.При дефекті покриття ацетабулярного компонента більше ніж 30 % застосовували кісткову пластику склепіння кортикально-губчастим трансплантатом. Для мобілізації стегна ми застосовували реліз сідничних м’язів, висічення суглобової капсули, міотомію аддукторів, відтинання від малого вертлюга сухожилка m. iliopsoas, остеотомію великого вертлюга з м’язами, що до нього прикріплюються, із подальшим його зведенням і фіксацією, а також flapping trochanter osteotomy. У 10 пацієнтів виконано вкорочуючі та корегуючі остеотомії стегнової кістки.Віддалені результати за шкалою Harris Hip Score були досліджені в 124 (78,98 %) оперованих пацієнтів у терміни від 3 до 14 років після артропластики. 36 пацієнтів перенесли артропластику обох кульшових суглобів. Середній термін спостереження — 7,8 ± 1,1 року. Узагальнені результати визнано відмінними (середній бал 93,67 ± 0,35) у 47 (37,9 %), добрі (середній бал 85,69 ± 0,52) — у 48 (38,7 %), задовільні (середній бал 75,56 ± 0,58) — у 22 (17,7 %) осіб. Погані результати (середній бал 46,96 ± 3,05) у 7 (5,7 %) пацієнтів були зумовлені розвитком нестабільністі компонентів. Асептична нестабільність у 5 пацієнтів виникла через 3–5, 7 і 11 років після артропластики. Септична нестабільність у 2 пацієнтів виникла через 6 і 7 років. У 5 пацієнтів у подальшому виконано ревізійне ендопротезування.При ендопротезуванні кульшового суглоба з приводу диспластичного коксартрозу у складних ситуаціях необхідно передбачати різні прояви анатомічних і біомеханічних порушень опорно-рухової системи, різні варіанти фіксації вертлюжного та стегнового компонентів, можливості застосування кісткової пластики й реконструкцій, а також не відкидати інтраопераційне рішення про зміни ходу оперативного втручання.

Identification of ustiloxins in false smut balls of rice based on high performance liquid chromatography-high resolution mass spectrometry

A sensitive method was developed for the simultaneous identification of five ustiloxins in the false smut balls of rice by high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry (HPLC-LTQ/Orbitrap MS). The samples were extracted with deionized water under ultrasonic condition for 10 min, then purified by a strong cation exchange column (PCX). The ustiloxins were separated on an Xselect HSS T3 column (150 mm x 2.1 mm, 3.5 μm) by using 0.1% (v/v) formic acid water solution and methanol as mobile phases with gradient elution at a flow rate of 0.3 mL/min. The full scan range was m/z 200-1 000. The confirmatory analysis of the target compounds was carried out by the accurate mass of quasi-molecular ion, isotope abundance ratio and qualitative fragments. The results showed that the five ustiloxins (A, B, C, D and F) were identified from the false smut balls with mass accuracy less than 1 x 10(-6) (1 ppm) and the absolute values of the deviation of isotope abundance ratio were not more than 3.3%. The product ions were consistent with the theoretical fragment mode. The recoveries were 90% to 105%. This method is accurate and sensitive for the simultaneous identification of the five ustiloxins, which can provide technical means for the research of the ability in toxin producing by Ustilaginodea virens.

Low Reversed Cyclic Loading Test for New Precast Concrete Beam to Column Connection

On the basis of the domestic and overseas scholars’ research, it is innovative to put forward a new precast frame beam-to-column connection. One full-scale beam-to-column connection in a precast concrete（PC）frame and a beam-to-column connection in a cast-in-place concrete structures were tested under uni-directional cyclic loading that simulated earthquake-type motions. The new-type beam-to-column joint in a precast concrete frame consisted of cast-in-place columns and precast beams. Test results showed that（a）The property and action of precast connections are similar to the cast-in-place connection, it showed that both precast connections and cast-in-place connection have similar seismic performance; (b) The cracking load of precast connection are similar to the cast-in-place connection; (c) All the columns of all specimens did not destroy, it illustrate that it conform to the strong column weak beam. (d) In this experiment test, because the control factor use the bending capacity of beam, it also play the same plastic hinge mechanism as the traditional component. All the longitudinal reinforcement destruction ahead of stirrup in beams, which should be confirmed the guiding ideology of strong shear weak bending. On the basis of the test results, design considerations for the beam-to column connection were recommended.

Analytical prediction of load deflection curves of external steel fibers R/C beam–column joints under monotonic loading

In this paper a simplified analytical model able to reproduce the flexural behavior of external beam–column joints under monotonic loading is presented, to be used for pushover analysis. The subassemblage (beam, column and joint) is subjected to a constant vertical load acting on the column and to a monotonically increasing lateral force applied at the tip of the beam. The model is specific for hooked steel fiber-reinforced concrete (FRC) and is designed to calculate the flexural response in the form of a load–deflection curve, of beam–column subassemblages. No bond failure and shear deformations are considered in the present paper. The model includes shear-to-moment interaction for beams and columns and is based on the determination of elastic–plastic behavior of the beam and of the columns, the latter being obtained from knowledge of the ultimate moment associated with the design axial force and deduced through a simplified moment axial force domain. The experimental results available in the literature are compared with the results obtained using the proposed model, showing good agreement. Finally, the model can be usefully utilized for the design of external joints with weak beams and strong columns.

Method development for the separation of monoclonal antibody charge variants in cation exchange chromatography, Part II: pH gradient approach

The cation exhange pH gradient approach was evaluated for the characterization of 10 model monoclonal antibodies including panitumumab, natalizumab, cetuximab, bevacizumab, trastuzumab, rituximab, palivizumab, adalimumab, denosumab and ofatumumab.This work shows that retention and resolution can be modelled in cation exchange pH gradient mode, based on only four initial runs (i.e. two gradient times and two mobile phase temperature). Only 6h were required for a complete method optimization when using a 100mm×4.6mm strong cation exchange column. The accuracy of the predictions was excellent, with an average difference between predicted and experimental retention times of about 1%.The 10 model antibodies were successfully eluted in both pH and salt gradient modes, proving that both modes of elution can be considered as multi-product charge sensitive separation methods. For most of the compounds, the variants were better resolved in the salt gradient mode and the peak capacities were also higher in the salt gradient approach. These observations confirm that pH gradient approach may be of lower interest than salt gradient cation exchange chromatography for antibody characterization.

Cyclic test for solid steel reinforced concrete frames with special-shaped columns

An experimental study was performed to investigate the seismic performance of solid steel reinforced concrete (SRC) frames with special-shaped columns that are composed of SRC special-shaped columns and reinforced concrete beams. For this purpose, two models of two-bay and three-story frame, including an edge frame and a middle frame, were designed and tested. The failure process and patterns were observed. The mechanical behaviors such as load-displacement hysteretic loops and skeleton curves, load bearing capacity, drift ratio, ductility, energy dissipation and stiffness degradation of test specimens were analyzed. Test results show that the failure mechanism of solid SRC frame with special-shaped columns is the beam-hinged mechanism, satisfying the seismic design principle of "strong column and weak beam". The hysteretic loops are plump, the ductility is good and the capacity of energy dissipation is strong, indicating that the solid SRC frame with special-shaped columns has excellent seismic performance, which is better than that of the lattice SRC frame with special-shaped columns. The ultimate elastic-plastic drift ratio is larger than the limit value specified by seismic code, showing the high capacity of collapse resistance. Compared with the edge frame, the middle frame has higher carrying capacity and stronger energy dissipation, but the ductility and speed of stiffness degradation are similar. All these can be helpful to the designation of solid SRC frame with special-shaped columns.

Fumonisin B1 contamination in breast milk and its exposure in infants under 6 months of age in Rombo, Northern Tanzania

The carry-over of fumonisin B1 from contaminated feed into dairy milk also suggests its carry-over from contaminated food into breast milk. This study assessed fumonisin B1 contamination in breast milk and associated exposures of infants under 6 months of age. Breast milk samples were collected from 131 lactating mothers and the weight of their infants was measured during the first month of lactation. Fumonisin B1 was extracted using methanol:acetone, cleaned up with Strong Anion Exchange columns and quantified by HPLC. Fumonisin B1 exposure in each child was estimated using deterministic approach. Out of the 131 samples, 58 (44.3%) contained fumonisin B1 at levels ranging from 6.57 to 471.05 ng/ml. Of the contaminated samples, 10.3% had fumonisin B1 levels above the EU limit of 200 ppb for fumonisins in infants' food. Exposure in the infants ranged from 0.78 to 64.93 µg/kg body weight (bw) per day (median, 3 µg/kg bw/day) and exceeded the provisional maximum tolerable limit of 2 µg/kg bw/day in 29% of the infants. In conclusion, breast milk from mothers in Northern Tanzania is contaminated with fumonisins at levels that lead to unacceptable exposures in infants. Strategies to prevent lactating mothers from fumonisin exposure are urgently needed to minimise fumonisin exposure in infants.

Ascidian (Chordata-Tunicata) glycosaminoglycans: extraction, purification, biochemical, and spectroscopic analysis.

Sulfated polysaccharides with unique structures of the chondroitin/dermatan and heparin/heparan families of sulfated glycosaminoglycans have been described in several species of ascidians (Chordata-Tunicata). These unique sulfated glycans have been isolated from-ascidians and characterized by biochemical and spectroscopic methods. The ascidian glycans can be extracted by different tissues or cells by proteolytic digestion followed by cetylpyridinium chloride/ethanol precipitation. The total glycans are then fractionated by ion-exchange chromatography on DEAE-cellulose and/or Mono Q (HR 5/5) columns. Alternatively, precipitation with different ethanol concentrations can be employed. An initial analysis of the purified ascidian glycans is carried out by agarose gel electrophoresis on diaminopropane/acetate buffer, before or after digestion with specific glycosaminoglycan lyases or deaminative cleavage with nitrous acid. The disaccharides formed by exhaustive degradation of the glycans is purified by gel-filtration chromatography on a Superdex-peptide column and analyzed by HPLC on a strong ion exchange Sax-Spherisorb column. 1H or 13C nuclear magnetic resonance spectroscopy in one or two dimensions is used to confirm the structure of the intact glycans.

Method development for the separation of monoclonal antibody charge variants in cation exchange chromatography, Part I: Salt gradient approach

Ion exchange chromatography (IEX) is a historical technique widely used for the detailed characterization of therapeutic proteins and can be considered as a reference and powerful technique for the qualitative and quantitative evaluation of charge variants. When applying salt gradient IEX approach for monoclonal antibodies (mAbs) characterization, this approach is described as time-consuming to develop and product-specific. The goal of this study was to tackle these two bottle-necks.By modeling the retention of several commercial mAbs and their variants in IEX, we proved that the mobile phase temperature was not relevant for tuning selectivity, while optimal salt gradient program can be easily found based on only two initial gradients of different slopes. Last but not least, the dependence of retention vs. pH being polynomial, three initial runs at different pH were required to optimize mobile phase pH. Finally, only 9h of initial experiments were necessary to simultaneously optimize salt gradient profile and pH in IEX. The data can then be treated with commercial modeling software to find out the optimal conditions to be used, and accuracy of retention times prediction was excellent (less than 1% variation between predicted and experimental values).Second, we also proved that generic IEX conditions can be applied for the characterization of mAbs possessing a wide range of pI, from 6.7 to 9.1. For this purpose, a strong cation exchange column has to be employed at a pH below 6 and using a proportion of NaCl up to 0.2M. Under these conditions, all the mAbs were properly eluted from the column. Therefore, salt gradient CEX can be considered as a generic multi-product approach.

Solve Cast-in-Place Floor Slab in Frame Structure Buildings in the Study of \" Strong Beam Weak Column\" Issue

With the development of construction technology and construction equipment, now almost all industrial and civil buildings are changing to frame structure. As a result of the differences in floor height, span and the thickness of the cast-in-place floor slab, so the frame column and beam stress is different. When the stress exceeds a certain limit, then it will result in the problem of “strong beam weak column”, and this affects the quality of the buildings, thus how to solve the strong beam weak column caused by the cast-in-place floor slab becomes very meaningful.

Behaviour of fibre-reinforced high-performance concrete in exterior beam-column joint

This paper presents the effect of reinforced high performance concrete (HPC) in exterior beam-column joint with and without fibre under monotonic loading. In this experimental investigation, cross-diagonal bars have been provided at the joint for reducing the congestion of reinforcement in joints, and also M75 grade of concrete with optimum mix proportion of 10 % silica fume and 0.3 % glass fibre was used. Four exterior beam-column joint sub-assemblages were tested. The specimens were divided into two types based on the reinforcement detailing. Type A comprises two joint sub-assemblages with joint detailing as per construction code of practice in India (IS 456-2000), and Type B comprises two joint sub-assemblages with joint detailing as per ductile detailing code of practice in India (IS 13920-1993). In each group there was one specimen of control mix and the remaining one specimen of fibre-reinforced mix. All the test specimens were designed to satisfy the strong column–weak beam concept. The performances of specimens were compared with the control mix and the fibre-reinforced mix. The results show that exterior beam-column joint specimens with silica fume and glass fibre in the HPC mix showed better performance.

Discovery of N-methyltetrahydroprotoberberines with κ-opioid receptor agonists-opioid receptor agonist activities from corydalis yanhusuo W. T. Wang by using two-dimensional liquid chromatography

Ethnopharmacological relevanceThe need for an efficacious analgesic without unwanted side effects is urgent. κ-opioid receptor agonists are known to exhibit potent analgesic effects and elicited fewer side effects than other opioid agonists. Thus in this study we chose the κ-opioid receptor as the target to identify the active components from traditional Chinese medicines (TCMs). Materials and methodsThe κ-opioid receptor was expressed in human embryonic kidney-293 T cells (HEK293T). Fluorometric Imaging Plate Reader (FLIPR) assay was used for the determination of Ca2+ response when κ-opioid receptor was activated. A novel 2D separation system employing C18HCE as the first dimension and a strong cation exchange column (SCX) as the second dimension was conducted for the purification of the active principles. ResultsWith the aid of HPLC-based activity profiling, activities could be linked to two peaks from Corydalis yanhusuo W. T. Wang (C. yanhusuo) extract. Two N-methyltetrahydroprotoberberines with κ-opioid receptor agonist activities were isolated for the first time from C. yanhusuo by using 2D-LC. ConclusionsOur study suggests that N-methyltetrahydroprotoberberines may serve as a new scaffold for κ-opioid receptor ligands. The strategy that we adopted can be applied to other naturally-occurring active alkaloids acting at different receptors.

1-Dodecyl-3-methylimidazolium chloride-assisted sample preparation method for efficient integral membrane proteome analysis.

Due to their extremely hydrophobic nature, the analysis of integral membrane proteins (IMPs) is of great challenge. Although various additives have been applied to improve the solubility of IMPs, they still suffer from low solubilization efficiency, incompatibility with trypsin digestion, or interference with MS detection. Herein, the systematic study on the effect of ionic liquid structure on membrane protein solubilization and trypsin biocompatibility was performed, based on which 1-dodecyl-3-methylimidazolium chloride (C12Im-Cl) was selected for the sample preparation of IMPs. Compared with other commonly used additives, such as sodium dodecyl sulfate (SDS), Rapigest, and methanol, C12Im-Cl showed the best performance. In addition, with a strong cation exchange trap column, it could be easily removed after trypsin digestion, which not only was beneficial to avoid protein precipitation during digestion but also had no adverse effect on LC-MS-based separation and detection. Such a C12Im-Cl-assisted sample preparation method was further applied to the membrane proteome analysis of rat brain. Compared with the SDS-assisted method, 1.4 and 3.5 times improvement on the identified IMP and hydrophobic peptide number were achieved (251 vs 178, and 982 vs 279). All these results demonstrated that the C12Im-Cl-assisted sample preparation method is of great promise to promote the large-scale membrane proteome profiling.

Rapid quantitative chiral amphetamines liquid chromatography–tandem mass spectrometry: Method in plasma and oral fluid with a cost-effective chiral derivatizing reagent

Methamphetamine is a widely abused psychostimulant containing a chiral center. Consumption of over-the-counter and prescription medications may yield positive amphetamines results, but chiral separation of l- and d-methamphetamine and its metabolite amphetamine can help determine whether the source was licit or illicit. We present the first LC–MS/MS method with precolumn derivatization for methamphetamine and amphetamine chiral resolution in plasma and oral fluid collected with the Oral-Eze® and Quantisal™ devices. To 0.5mL plasma, 0.75mL Oral-Eze, or 1mL Quantisal specimen racemic d11-methamphetamine and amphetamine internal standards were added, followed by protein precipitation. Samples were centrifuged and supernatants loaded onto pre-conditioned Phenomenex® Strata™-XC Polymeric Strong Cation solid phase extraction columns. After washing, analytes were eluted with 5% ammonium hydroxide in methanol. The eluate was evaporated to dryness and reconstituted in water. Derivatization was performed with 1-fluoro-2,4-dinitrophenyl-5-l-alanineamide (Marfey's reagent) and heating at 45°C for 1h. Derivatized enantiomer separations were performed under isocratic conditions (methanol:water, 60:40) with a Phenomenex® Kinetex® 2.6μm C18 column. Analytes were identified and quantified by two MRM transitions and their ratio on a 3200 QTrap (AB Sciex) mass spectrometer in ESI negative mode. In all three matrices, the method was linear for all enantiomers from 1 to 500μg/L, with imprecision and accuracy of ≤11.3% and 85.3–108%, respectively. Extraction efficiencies ranged from 67.4 to 117% and matrix effects from −17.0 to 468%, with variation always ≤19.1%. Authentic plasma and OF specimens were collected from an IRB-approved study that included controlled Vicks® VapoInhaler™ administration. The present method is sensitive, selective, economic and rapid (separations accomplished in <10min), and improves methamphetamine result interpretation.