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Analytica Chimica Acta (v.559, #1)

Outside front cover - Editorial Board (pp. co1).

Calendar of forthcoming meetings (pp. n1).

Contents (pp. v-vi).

Role of calcium binding in protein structural changes and phospholipid–protein interactions studied by capillary isoelectric focusing with whole column imaging detection by Tao Bo; Janusz Pawliszyn (pp. 1-8).

A variety of biochemical and physical properties of proteins are regulated by calcium ion (Ca²⁺) binding with varying specificity and affinity. Calcium ion binding can adjust the phospholipid–protein interactions through changing the properties of phospholipid membrane. As an attractive detection technique, whole column imaging detection (WCID) coupled to capillary isoelectric focusing (cIEF) displays several advantages in the study of protein–ligand and protein–protein interactions, including fast and high-efficient separation, high resolution, and simple operation. In this study, a cIEF–WCID method was evaluated for studying the effect of Ca²⁺ binding on protein structural changes and phospholipid–protein interactions. Four proteins with different isoelectirc point (p I), trypsin inhibitor (p I=4.5), β-lactoglobulin B (p I=5.2), phosphorylase b (p I=6.3), and trypsinogen (p I=9.3), were used for this purpose. The targeted proteins exhibited altered cIEF profiles due to protein conformation changes resulting from the Ca²⁺ binding. The study showed that Ca²⁺ can be buried in the phospholipid membrane, modify the membrane property, and change the phospholipid–protein interactions. The utility of the cIEF–WCID technique demonstrates that the calcium binding plays a crucial role in the protein structural changes and the phospholipid–protein interactions, and elucidates the possible mechanisms involved in calcium–protein binding and calcium bound phospholipid–protein interactions.

Keywords: Calcium binding; Phospholipids; Protein; Interaction; Capillary isoelectric focusing; Whole column imaging detection

Development and validation of a capillary zone electrophoresis method for the determination of propranolol and N-desisopropylpropranolol in human urine by Juan Jos� Berzas Nevado; Juana Rodr�guez Flores; Gregorio Casta�eda Pe�alvo; Francisco Javier Guzm�n Bernardo (pp. 9-14).

A simple, rapid and sensitive procedure using solid phase extraction and capillary zone electrophoresis for the determination of propranolol (a beta-blocker) and one of its metabolites, N-desisopropylpropranolol, has been developed and validated. The optimum separation of both analytes was obtained in a 37cm×75μm fused silica capillary using 20mmol/L phosphate buffer (pH 2.2) as electrolyte, at 25kV and 30°C, and hydrodynamic injection for 5s. Prior to the electrophoretic separation, the samples were cleaned up and concentrated using a C₁₈ cartridge and then, eluted with methanol, allowing a concentration factor of 30.Good results were obtained in terms of precision, accuracy and linearity. The limits of detection were 28 and 30μg/L for N-desisopropylpropranolol and propranolol, respectively. Additionally, a robustness test of the method was carried out using the Plackett–Burman fractional factorial model with a matrix of 15 experiments.The presented method has been applied to the determination of both compounds in human urine.

Keywords: Capillary zone electrophoresis; Propanolol; N; -desisopropylpropanolol; Ruggedness; Urine determination

Analytical solutions for velocity, temperature and concentration distribution in electroosmotic microchannel flows of a non-Newtonian bio-fluid by Siddhartha Das; Suman Chakraborty (pp. 15-24).

In this paper, analytical solutions are derived, describing the transport characteristics of a non-Newtonian fluid flow in a rectangular microchannel, under the sole influence of electrokinetic forces. Apart from estimating the fully-developed velocity and temperature distributions, an explicit expression is derived for solutal concentration distribution within the microchannel. Finally, as an illustrative case study, the flow behaviour of a blood sample is analyzed, in which the flow parameters are modeled as functions of the hematocrit fraction in the sample. It is revealed that a higher hematocrit fraction may result in significant reductions in species concentration levels, on account of stronger dispersions in the velocity profiles, characterized by more significant viscous effects. It is also demonstrated that cases in which characteristic length scale of RBC suspensions turns out to be consequential relative to the microchannel dimensions, a significant augmentation in the electroosmotic transport may occur. Such observations can be of particular significance in the design of electroosmotically actuated bio-microfluidic systems as efficient solutal carriers.

Keywords: Electro-osmosis; Microchannel; Non-Newtonian; Bio-fluid

Determining morphine in biologic fluids of rats by gas chromatography–mass spectrometry by Maw-Rong Lee; Sheng-Chien Yu; Bao-Huey Hwang; Chung-Yu Chen (pp. 25-29).

This study describes a sensitivity and selectivity approach based on gas chromatography–mass spectrometry to determinate morphine levels in rat biologic fluids. Optimized experimental conditions of solid-phase extraction (SPE), including pH of the sample, solvent composition, and various sorbents, are examined herein. The largest recovery is greater than 94.0% for morphine, is achieved with a mixed sorbent C₈/SCX and mixed elution CHCl₃/ iso-propanol (9:1) at pH 6.8. Acetylation accomplished with acetic anhydride is utilized to derivatize morphine to 3,6-diacetylmorphine for GC/MS analysis. The proposed method was precise and a wide linear range from 0.5 to 500ngmL⁻¹. A detection limit of 0.31ngmL⁻¹ in urine is achieved. The maximum ratio of morphine glucuronide to morphine in the blood of rat is 6 to 1. A terminal half-life of morphine in blood is calculated as around 120min.

Keywords: Morphine; Solid-phase extraction; Biologic fluids; Derivatization; Gas chromatography/mass spectrometry

Effect of the systemic versus inhalatory administration of synthetic glucocorticoids on the urinary steroid profile as studied by gas chromatography–mass spectrometry by Monica Mazzarino; Francesca Rossi; Laura Giacomelli; Francesco Botr� (pp. 30-36).

This paper presents a gas chromatography–mass spectrometry (GC–MS) study carried out on human urine to verify whether the administration of glucocorticoids can affect the urinary steroid profile, and especially the levels of endogenous glucocorticoids, androgens and their main metabolites.Betamethasone and beclomethasone, administered either systemically (per os or i.m.) or locally (by inhalation) have been studied. The determination of the urinary levels of endogenous glucocorticoids and androgens was carried out by GC–MS in electron impact ionization mode. Data were evaluated taking into account the baseline individual variability, and compared with values obtained on a control group.Detectable differences were recorded in the steroids metabolites excretion profiles between men and women. The circadian variability of the steroid profile was the same for both sexes, showing a maximum during the morning hours. After systemic treatment with synthetic glucocorticoids, the relative urinary concentrations of corticosteroids, androgens and of their metabolites were significantly altered, recording a transient decrease of the concentration of cortisol and tetrahydrocortisol and a parallel, although less pronounced, increase of the concentration of testosterone, epitestosterone and related androgenic steroids; while no effects were recorded if the administration was by inhalation.

Keywords: Glucocorticoids; Betamethasone; Beclomethasone; Androgenic anabolic steroids; GC–MS; Urine analysis; Antidoping analysis

High-throughput pharmacokinetic method: Cassette dosing in mice associated with minuscule serial bleedings and LC/MS/MS analysis by Takaho Watanabe; Daniela Schulz; Christophe Morisseau; Bruce D. Hammock (pp. 37-44).

A method for pharmacokinetic studies using cassette dosing associated with serial bleeding in mice is described. PK profiles of four soluble epoxide hydrolase inhibitors were determined following oral, subcutaneous or intraperitoneal administration individually or in cassette dosing. Parent analyses were performed on only 5μL of whole blood from serial bleeds (up to 10 per animal), by LC/MS/MS. An accuracy (88–100%) and precision (<10% RSD) were observed, leading to reliable datum points for PK calculation. PK profiles, T_max, C_max and half-life values after cassette dosing were similar to the individual PK results. This method dramatically increases speed of data collection while dramatically reducing cost and animal usage. The results presented here clearly indicate that this proposed method could be applicable to high-throughput PK studies.

Keywords: Pharmacokinetics; Serial bleeding; Cassette dosing; LC/MS/MS; High-throughput

Determination of 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP) in hemoglobin using on-line coupling of restricted access material to liquid chromatography–mass spectrometry by R. Busquets; L. Puignou; M.T. Galceran (pp. 45-53).

A new method for the analysis of 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP) in hemoglobin has been developed. The method is based on a protein hydrolysis with hydrochloric acid to release the bound PhIP followed by purification and preconcentration steps. The sample clean-up consisted of an ultrafiltration of the hydrolyzed protein and preconcentration of PhIP by freeze-drying. An ultimate cleaning step of the sample using restricted access material (RAM) coupled to liquid chromatography performs extraction and enrichment of the analyte from the sample matrix. Three different RAM columns were tested, LiChrospher^�ADS C₄, C₈ and C₁₈. Two mass spectrometers (ion trap and triple quadrupole) operating in different modes were also evaluated for the determination of PhIP released from hemoglobin adducts. Quality parameters were established and good precision (relative standard deviation (R.S.D.)<15%), suitable accuracy (>95%) and low detection limits were reached, up to 0.03fmol PhIP/mg hemoglobin, when using the triple quadrupole.

Keywords: Heterocyclic amines; PhIP; Biomarker; Hemoglobin; RAM; mass spectrometry

Determination of cocaine contamination on banknotes using tandem mass spectrometry and pattern recognition by Sarah J. Dixon; Richard G. Brereton; James F. Carter; Richard Sleeman (pp. 54-63).

Tandem mass spectrometry is used to monitor the contamination of banknotes by cocaine. By introducing a series of banknotes into an instrument a distribution of contamination can be obtained. The distribution of samples arising from defendants where the banknotes have been in close proximity to cocaine should differ from the distribution from the general background population. Peak picking and integration is used to produce a series of intensity readings for a batch of banknotes. By visually inspecting these distribution, and applying a variety of chemometric methods (principal components analysis, cluster analysis and class modelling via Mahalanobis distance) it is possible to discriminate effectively between the two classes of distribution (7157 background notes and 4826 case notes alleged to be from drug dealers). By calculating the Mahalonobis distance over 100 bootstrap iterations, background samples were correctly classified 96.48% of the time, while case samples were correctly classified 89.37% of the time.

Keywords: Tandem mass spectrometry; Cocaine; Banknotes; Pattern recognition; Principal components analysis

Identification of archaeological ivories using FT-Raman spectroscopy by Howell G.M. Edwards; Rachel H. Brody; Nik F. Nik Hassan; Dennis W. Farwell; Sonia O’Connor (pp. 64-72).

FT-Raman spectroscopy has been used successfully for the non-destructive identification of modern ivories and is evaluated here for the identification of osseous materials from archaeological sites. Results on archaeological ivories are reported and the problems faced in matching FT-Raman spectra to standards for the validation of these materials are highlighted. Archaeological specimens of different dates, provenance and taphonomic history, including both conserved and unconserved items, have been analysed.

Keywords: Mammalian; Teeth; Artefacts; Raman; Spectroscopy; Diagnostic; Microscopy

Computational design and synthesis of molecularly imprinted polymers with high binding capacity for pharmaceutical applications-model case: Adsorbent for abacavir by Iva Chianella; Kal Karim; Elena V. Piletska; Christopher Preston; Sergey A. Piletsky (pp. 73-78).

This paper reports the development of selective polymers with high binding capacity suitable for large scale solid-phase extraction (SPE), e.g. for industrial applications. The technology of molecular imprinting was employed in the synthesis of selective molecularly imprinted polymers (MIPs). Abacavir, which is a HIV-1 reverse transcriptase inhibitor, was chosen as the target analyte. An already established computational protocol, developed in our group, was employed to select the best monomers leading to polymers with high binding capacity for the target compound. Three different monomer compositions were chosen for the synthesis. The synthesised materials were then tested for the rebinding of abacavir in solid-phase extraction using several different conditions (buffered/non-buffered solutions and in the presence/absence of organic solvents). The best MIP showed a surprisingly high binding capacity, up to 157mg of drug/g of adsorbent. The high binding capacity could make this polymer suitable for industrial applications to purify and/or concentrate the drug during its production.

Keywords: Molecularly imprinted polymers; Solid-phase extraction; Abacavir; Binding capacity

Preparation of pyrenebutyric acid-modified magnesia–zirconia stationary phases using phosphonate as spacers and their application to the separation of fullerenes by Qiong-Wei Yu; Jun Yang; Bo Lin; Yu-Qi Feng (pp. 79-88).

A novel method was proposed for the preparation of pyrenebutyric acid-modified magnesia–zirconia stationary phases. Pyrenebutyric acid was grafted to magnesia–zirconia composites with different pore sizes via the sodium salt of cis-(3-methyloxiranyl)phosphonic acid (fosfomycin) as spacers. Aminated fosfomycin was first absorbed onto the surface of magnesia–zirconia composites during the preliminary step to provide amino and hydroxy reactive sites. And then the pyrenebutyric acid was covalently attached to the amine or hydroxyl groups via amide or ester bonds. The resulting stationary phases were characterized by elemental analysis, diffused reflectance FT-IR, nitrogen adsorption analysis and¹³C solid state NMR spectra. The HPLC separation of fullerenes on the new stationary phases with different pore sizes was also investigated. The chromatographic performance showed a dependence on the pore size of the magnesia–zirconia matrix. Little retention of fullerenes was observed on the stationary phase with pore sizes about 4.5nm. However, on the modified magnesia–zirconia with pore sizes about 10nm, selectivity factors ( α) for C₇₀/C₆₀ separation were determined to be 1.76, 2.29, 2.41, 3.10, with carbon disulfide, chlorobenzene, xylene and toluene as mobile phases, respectively. And the high solubility of fullerenes in these solvents dramatically increased the overall potential with regard to preparative fullerene purification. Among the reported stationary phases with pyrene ligands, the pyrenebutyric acid-modified magnesia–zirconia (PYB-F-(ZrO₂–MgO)) with larger pore sizes exhibited the best selectivity for fullerenes. The thermodynamic and kinetic behavior of fullerenes was also examined.

Keywords: Fullerenes; Separation; Pyrenebutyric acid; Magnesia–zirconia; Stationary phase; HPLC

Vinyl crown ether as a novel radical crosslinked sol–gel SPME fiber for determination of organophosphorus pesticides in food samples by Lingshuang Cai; Shuling Gong; Mao Chen; Caiying Wu (pp. 89-96).

A method based on solid-phase microextraction and gas chromatography flame photometric detector for the determination of organophosphorus pesticides (OPPs) in food samples was described. Three kinds of vinyl crown ether polar fibers were prepared with sol–gel process and used for the analytes. The new coatings showed higher extraction efficiency and sensitivity for organophosphorus pesticides compared with commercial fibers—85μm PA and 65μm PDMS-DVB. Specifically, the benzo-15-crown-5 coating was the most effective for the target analytes. Several factors affecting the performance of SPME such as extraction temperature and time, salt addition, and dilution ratios of samples were optimized. The apparent recoveries of spiked food samples (apple juice, apple and tomato) were determined to be over 55.3% and the limits of detection (LODs) were in the range of 0.003–0.09ng/g for the OPP studied. The method was applied to determine the concentrations of OPP in real food samples.

Keywords: Sol–gel technology; Solid-phase microextraction; Pesticides; Organophosphorus compounds; Vinyl crown ether

Use of solid phase microextraction in diffusive sampling of the atmosphere generated by different essential oils by P. L�pez; M.A. Huerga; R. Batlle; C. Nerin (pp. 97-104).

This work describes the development and optimisation of a complete headspace-solid phase microextraction (HS-SPME) procedure for qualitative and quantitative analysis of the equilibrium headspace generated by a number of essential oils (EOs) with potential applications in active packaging, including basil ( Ocinum basilicum), clove ( Sygyzium aromaticum), rosemary ( Rosmarinus officinalis), citronella ( Melissa officinalis), and cinnamon ( Cinnamonum zeylanicum). The method consists of a combination of fully exposed HS-SPME for qualitative analysis and diffusive HS-SPME for quantitative determination.First, complete optimisation of a fully exposed HS-SPME procedure was carried out by means of a combination of a Plackett–Burman screening experimental design and response surface modelling (RSM). The results were used to fully describe the atmosphere generated by the EOs and to select the most relevant compounds for further consideration.The fibres were then calibrated (i.e. the uptake rate was calculated) by exposing them to known concentrations of terpenes in closed extraction vials. With a sampling time of 30min at 20°C, uptake rates ranged from 2.2 to 3.3pg (minppb_v)⁻¹. Results were checked by sampling over extended periods of times, with the observed variation being less than 5%, despite a 10-fold increase in extraction time. The results were further validated by comparing the calculated diffusion coefficients with theoretical data. The ratios of experimental:theoretical values varied between 0.85 and 1.05. The sensitivity of the uptake rate to headspace concentration was also investigated; variation of less than 10% was observed despite changes in concentration of four orders of magnitude. The new diffusive sampling method proved to give robust determinations of all the test analytes (by contrast, HS-SPME failed for camphene, camphor and cinnamaldehyde), providing repetitivity and intermediate precision lower than 9% (the values for HS-SPME were 10 and 12%, respectively).

Keywords: Essential oils; Terpenes; Diffusive (passive) sampling; Headspace-solid phase microextraction; Active packaging

Major and trace metal extraction from soil by EDTA: Equilibrium and kinetic studies by Nastaran Manouchehri; St�phane Besancon; Alain Bermond (pp. 105-112).

EDTA, a powerful chelating agent, is used extensively in soil sciences to determine the bioavailability of trace metals and their possible decontamination from polluted soils. Because of its non-selective nature, the co-dissolution of major elements also occurs, in addition to the extraction of trace metal ions.In this work, the reactivity of trace and major elements (Pb, Cu, Cd, Al, Fe, Ca and Mg) with different concentrations of EDTA was studied in eight soil samples (Burgundy, France). The limit between lack and excess of EDTA with respect to total metal extracted, determined after 24h of reaction for different types of soil varied from 0.002 to 0.05M, respectively.For calcareous samples the amount of Pb, Cu and Cd extracted by EDTA was reduced to 50% of that extracted in non-calcareous soils.From the kinetic point of view, the extraction behavior of major elements seemed to depend heavily on excess or lack of EDTA and the soil Ca content. For a lack of EDTA, different competitive behaviors were revealed for the major elements (Al, Ca, Fe and Mg) towards the reagent, depending on the soil matrix.According to these experimental results, the mass balance between the reagent and cations in any EDTA–soil media is strongly controlled by major metal extraction. When choosing the reagent concentration needed to extract the trace metals efficiently, all the extractable metal present in the concerned sample must be taken into account.

Keywords: Soil; Major cations; Trace metal; EDTA; Kinetics

Speciation of dissolved Fe(II) and Fe(III) in environmental water samples by micro-column packed with N-benzoyl- N-phenylhydroxylamine loaded on microcrystalline naphthalene and determination by electrothermal vaporization inductively coupled plasma-optical emission spectrometry by Chaomei Xiong; Zucheng Jiang; Bin Hu (pp. 113-119).

A novel solid phase extraction technique for the speciation of trace dissolved Fe(II) and Fe(III) in environmental water samples was developed by coupling micro-column packed with N-benzoyl- N-phenylhydroxylamine (BPHA) loaded on microcrystalline naphthalene to electrothermal vaporization inductively coupled plasma-optical emission spectrometry (ETV-ICP-OES). Various influencing factors on the separation and preconcentration of Fe(II) and Fe(III), such as the acidity of the aqueous solution, sample flow rate and volume, have been investigated systematically, and the optimized operation conditions were established. At pH 3.0 Fe(III) could be selectively retained by micro-column (20mm×1.4mm, i.d.) packed with BPHA immobilized on microcrystalline naphthalene, and Fe(II) passed through the micro-column. Both Fe(II) and Fe(III) could be adsorbed by the micro-column at pH 6.5. Thus, the total Fe could be determined without the need for preoxidation of Fe(II) to Fe(III). The retained Fe(III) or the Fe(II) and Fe(III) was subsequently eluted by 0.1ml of 1moll⁻¹ HCl. The adsorption capacity of the solid phase adsorption material was found to be 45.0mgg⁻¹ for Fe(III) at pH 3.0 and 65.3mgg⁻¹ for Fe(II) at pH 6.5, respectively. The detection limit (3 σ) of 0.053μgl⁻¹ was obtained with a practical enrichment factor of 156 at a sample volume of 17ml. The relative standard deviations of 4.2% and 4.6% ( C_Fe(III)= C_Fe(II)=10μgl⁻¹, n=7) for Fe(III) and total iron were found, respectively. The method was successfully applied to the determination of trace Fe(II) and Fe(III) in environmental water samples (East Lake water, local tap water and mineral water). In order to validate the method, the developed method was applied to the determination of total iron in certified materials of NIES NO.10-b rice flour and GBW07605 tea leaves, and the results obtained were in good agreement with the certified values.

Keywords: Iron; Speciation; Microcrystalline naphthalene; N; -Benzoyl-; N; -phenylhydroxylamine; Electrothermal vaporization inductively coupled plasma-optical emission spectrometry

Temperature-dependent photoluminescence of water-soluble quantum dots for a bioprobe by Tian-Cai Liu; Zhen-Li Huang; Hai-Qiao Wang; Jian-Hao Wang; Xiu-Qing Li; Yuan-Di Zhao; Qing-Ming Luo (pp. 120-123).

The photoluminescence of water-soluble CdSe/ZnS core/shell quantum dots is found to be temperature-dependent: as temperature arising from 280K to 351K, the photoluminescence declines with emission peak shifting towards the red at a rate of ∼0.11nmK⁻¹. And the studies show that the photoluminescence of water-soluble CdSe/ZnS quantum dots with core capped by a thinner ZnS shell is more sensitive to temperature than that of ones with core capped by a thicker one. That is, with 50% decrement of the quantum yield the temperature of the former need to arise from 280K to 295K, while the latter requires much higher temperature (315.6K), which means that the integrality of shell coverage is a very important factor on temperature-sensitivity to for the photoluminescence of water-soluble CdSe/ZnS quantum dots. Moreover, it is found that the water-soluble CdSe quantum dots with different core sizes, whose cores are capped by thicker ZnS shells, possess almost the same sensitivity to the temperature. All of the studies about photoluminescence temperature-dependence of water-soluble CdSe/ZnS core/shell quantum dots show an indispensable proof for their applications in life science.

Keywords: Quantum dot; Temperature; Fluorescence; Photoluminescence; Bioprobe

Capability of detection and three-way data by M.C. Ortiz; L.A. Sarabia; I. Garc�a; D. Gim�nez; E. Mel�ndez (pp. 124-136).

Due to the possibility of making analytical determinations in the presence of non-modelled interferents and to identify the analyte of interest, calibrations based on scores of PARAFAC decomposition of three-way data are becoming increasingly important in routine analysis.Furthermore, the IUPAC and EU (European Decision 2002/657/EC) have accepted the definition given by the ISO 11843 for the capability of detection as the minimum net quantity detectable with a pre-set probability of false positive and false negative. What is more, recently our research group has generalised this definition of capability of detection, CCβ, to multivariate calibrations. In practice, CCβ is a good measure of the quality of the calibration because in its definition it brings together analytical sensitivity with precision in analytical determinations.This paper studies the effect of the pre-treatment of the sample, the signal/noise ratio and the second-order advantage on CCβ when using second-order signals modelled by PARAFAC. All of them are experimental factors which influence the quality of the calibration. Analytical pre-treatment is habitual in the analysis of real samples. Specifically, we analyse the effect of the extraction phase and the clean-up of milk samples on the determination of chlortetracycline by HPLC-DAD. It is shown that it is more efficient to do the joint PARAFAC decomposition of the pure standards with the milk samples.Secondly, the effect of asymmetry on CCβ, according to the path of the noise of the signals, is studied. Specifically, in the determination of naphthalene by excitation-emission spectroscopy, EEM, it is the emission spectrum which limits the capability of detection. It is shown that by eliminating the spectra with the poorest signal/noise ratio in this path, the capability of detection can be substantially improved.Thirdly, the impact on CCβ when the second-order advantage is used, that is when PARAFAC calibration is used over samples with an unknown interference not modelled in the calibration step. This is important to apply a PARAFAC calibration to routine analysis in the IUPAC and European Decision framework. Specifically, in the determination of enrofloxacine in poultry feeding water through excitation-emission fluorescence CCβ is evaluated when the PARAFAC is built only with calibration samples or with the calibration samples plus the test samples with uncalibrated and unknown interferent.

Keywords: ISO 11843; European Decision 2002/657/EC; Capability of detection; Minimum detectable net concentration; Detection limit; Maximum limit permitted; Fluorescence spectroscopy; HPLC-DAD; Chlortetracycline; Milk; Naphthalene; PARAFAC; Bilinear PLS; Trilinear PLS; Second-order advantage

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Analytica Chimica Acta (v.559, #1)