Determination of salbutamol enantiomers in human plasma and urine by chiral high-performance liquid chromatography

Enantiomers of salbutamol were directly separated (R_s=1.16) and quantitated at therapeutic concentrations after solid-phase extraction from human plasma and urine by normal-phase high-performance liquid chromatography on a chiral column with fluorescence detection. The assay was linear for each enantiomer between 1.25 and 500 ng ml⁻¹ and had a minimum limit of detection of 250 pg ml⁻¹. A 3-ml plasma or 1-ml urine sample was required for quantitation at therapeutic doses. Inter-day variation was 50% for S-(+)- and 6.5% for R-(−)-salbutamol. The assay was used to compare enantioselective disposition after single doses of racemate by the intravenous, oral and rectal routes.     

Ultrasensitive detection of Shiga toxin 2 and its variants in Shiga toxin‐producing Escherichia coli strains by a time‐resolved fluorescence immunoassay

A rapid and sensitive two‐step time‐resolved fluorescence immunoassay (TRFIA) was developed for the detection of Shiga toxin 2 (Stx2) and its variants in Shiga toxin‐producing Escherichia coli (STEC) strains. In sandwich mode, a monoclonal antibody against Stx2 was coated on a microtiter plate as a capture antibody. A tracer antibody against Stx2 labeled with europium(III) (Eu³⁺) chelate was then used as a detector, followed by fluorescence measurements using time‐resolved fluorescence. The sensitivity of Stx2 detection was 0.038 ng/ml (dynamic range, 0.1–1000 ng/ml). The intra‐ and inter‐assay coefficients of variation of the assay were 3.2% and 3.6%, respectively. The performance of the established assay was evaluated using culture supernatants of STEC strains, and the results were compared to those of a common HRP (horseradish peroxidase) labeling immunosorbent assay. A polymerase chain reaction (PCR) for the detection of genes encoding Stx1 and Stx2 was used as the reference for comparison. Correlation between the Stx2‐specific TRFIA and PCR was calculated by the use of kappa statics, exhibiting a perfect level of agreement. The availability of the sensitive and reliable Stx2‐specific TRFIA method for quantifying Stx2 and its variants in STEC strains will complement bacteria isolation‐based platform and aid in the accurate and prompt diagnosis of STEC infections.     

Detection of Vascular Endothelial Growth Factor Based on Gold Nanoparticles and Immunoreaction Using Resonance Light Scattering

In the study, a new assay of vascular endothelial growth factor (VEGF) has been developed by the use of gold nanoparticles (GNPs)–anti-VEGF conjugates. The immunoreaction between GNPs–anti-VEGF conjugates and VEGF took place in pH?7.5 PBS buffer solution after the addition of VEGF. The formation of GNPs modified VEGF immunocomplex resulted in the enhanced resonance light scattering (RLS) intensity at 388.0 nm. Under the optimal conditions, the magnitude of enhanced RLS intensity (ΔI _RLS) was proportional to the VEGF concentration in the range from 100 to 1,500 pg?mL^?1, with a detection limit of 60 pg?mL^?1. The surface plasma resonance absorption spectrum, the characteristics of RLS, the VEGF immunocomplex, and the optimum conditions of the immunoreaction have all been investigated. The VEGF concentrations of 20 serum specimens detected by the developed assay showed consistent results in comparison with those obtained by commercially available enzyme-linked immunosorbent assay kit.     

High-performance liquid chromatographic assay for the measurement of melphalan and its hydrolysis products in perfusate and plasma and melphalan in tissues from human and rat isolated limb perfusions

A sensitive, specific and rapid reversed-phase high-performance liquid chromatographic (HPLC) assay was developed for the quantitation of melphalan and its hydrolysis products in samples from the isolated perfusion of human and rat limbs. Samples of perfusate, plasma and tissue were analysed, following methanol precipitation, using a phenyl column and fluorescence detection. Dansyl-arginine (38 μg ml⁻¹) was employed as the internal standard. Good resolution was observed allowing quantitation of melphalan, monohydroxymelphalan (MOH) and dihydroxymelphalan (DOH) in perfusate and plasma and melphalan in tissue. The mean recoveries of melphalan, MOH and DOH from perfusate and plasma were all 100 ± 10%. The recovery of melphalan in tissue was 93.5%. A linear response was demonstrated for melphalan in the concentration range 1.8–56.8 μg ml⁻¹, for DOH in the concentration range 0.5–30.0 μg ml⁻¹ and for MOH in the range 1.4–25.1 μg ml⁻¹, in perfusate and plasma. The lower limits of quantitation of melphalan, MOH and DOH in perfusate and plasma were 1.4, 2.4 and 1.2 ng on column, respectively, and 7.2 ng of melphalan on column in tissue. Intra-assay coefficients of variation (C.V.) for melphalan, MOH and DOH, at low and high concentrations were all less than 5% and the inter-assay C.V.s were less than 9%. An ultra-filtration study to determine the protein binding of melphalan and the hydrolysis products showed that the unbound fractions (f_u) of melphalan in buffer containing dextran and bovine serum albumin were 0.873 and 0.521, respectively. The assay was used to quantitate melphalan and its hydrolysis products in samples from isolated perfusions in the human limb and rat hindlimb.     

Utility of the food colorant erythrosine B as an effective green probe for quantitation of the anticancer sunitinib. Application to pharmaceutical formulations and human plasma

Sunitinib is a tyrosine kinase inhibitor used for the treatment of renal cell carcinoma and gastrointestinal stromal tumors. In this study, two spectroscopic methods, spectrofluorometric and spectrophotometric, were utilized to quantify sunitinib in different matrices. In method I, the native fluorescence of erythrosine B was quenched by forming ion-pair complex with increasing quantities of sunitinib. This approach was utilized for measuring sunitinib in its dosage forms and spiked plasma. After excitation at 528 nm, the quenching of fluorescence is linearly related to the concentration across the range of 0.05–0.5 μg mL⁻¹ at 550 nm in Britton–Robinson buffer (pH 4.0), with a correlation value of 0.9999 and a high level of sensitivity with detection limit down to 10 ng mL⁻¹. Method II relies on spectrophotometric measurements of the produced complex at 550 nm across a range of 0.5–10.0 μg mL⁻¹, with good correlation value of 0.9999. This method has a detection limit down to 0.16 μg mL⁻¹. The proposed methodologies were validated according to International Conference on Harmonization (ICH) guidelines with satisfactory results. The stoichiometry of the reaction was determined through the application of Job's method, while the mechanism of quenching was investigated by employing the Stern–Volmer plot. The designated methods were used to estimate sunitinib in its capsules and in spiked human plasma. Additionally, the statistical analysis of the data revealed no substantial differences when compared to previous reported spectroscopic method. Green assessment tools provide further details about the eco-friendly nature of the methods.     

4-Azido-7-nitrobenzoxadiazole as innovative clickable fluorescence probe for trace and selective quantification of ethinylestradiol in human plasma

Quantification of ethinylestradiol (EE) in biological matrices is challenging as it is a very potent drug with a very low C_max (75 pg.ml⁻¹). Despite the high sensitivity of fluorometric methods, the detection of EE was confined because its structure exhibited very limited fluorescence. Therefore, it must be derivatized first using a fluorogenic agent to produce a more potent fluorescence derivative to achieve the desired ultrasensitive bioanalysis. Here, for the first time, we proposed a promising click fluorescent probe, 4-azido-7-nitrobenzoxadiazole (NBD-AZ) to react with the alkyne group of EE, with the help of copper sulphate and l -ascorbic acid to give a highly fluorescent and stable 1,2,3-triazole derivative. Density functional theory calculation revealed how the triazole formation affects the quantum yield and fluorescence of click reaction product when compared with NBD-AZ. The resulting triazole exhibited a strong signal at a wavelength of 540 nm after excitation at 470 nm. Reaction parameters impacting the intensity of fluorescence were cautiously studied and optimized. The suggested approach has shown outstanding performance, high linearity (25–300 pg.ml⁻¹) and a low detection limit of 7.5 pg.ml⁻¹_. The enhanced sensitivity and selectivity were exploited for analyzing EE in plasma using liquid–liquid extraction for samples cleaning up without interference from any biological components and with a mean % recovery of 100.13 ± 0.39. Accuracy, sensitivity, selectivity, simplicity, and cost–effectiveness make this approach a convincing, promising, and appealing alternative to the reported analytical methods for EE bioanalysis in different matrices.     

Application of a white and green spectrofluorimetric approach for facile quantification of amlodipine,a hypotensive drug,in batch materials,dosage forms,and biological fluids; content homogeneity testing

The suggested study adheres to a particular protocol to ensure that the process is environmentally friendly and sustainable. It is worth mentioning that several tools have been adopted as prospective measures of the method greenness. Fortunately, the established analytical method is identified as white by the white analytical chemistry (WAC) concept, which uses the red/ green/blue color scheme (RGB 12 tool) to combine ecological and functional factors for the first time in studying of the cited drug. Amlodipine (AMD), a cardiovascular treating agent, belongs to the dihydropyridine class of oral calcium channel-blocking agents. This article presents a novel, simple, green, one-pot-processed, fast, and ultrasensitive fluorimetric approach for monitoring and assessment of AMD using molecular-size-dependent fluorescence augmentation of the light scattering-driven signal of eosin, a biological stain at a wavelength of 415 nm. This enhancement was directly proportional to the size of the produced complex. The linearity range was from 30 to 900 ng mL⁻¹, with corresponding sensitivity limits (detection and quantitation levels) of 9.2 and 28 ng mL⁻¹, respectively. The planned approach was also successfully used to track AMD content in bulk, dosage forms, and bio-fluids (human plasma and urine). The developed method's eco-friendliness was established by different eco-rating metric tools.     

快速同时检测玉米赤霉烯酮和脱氧雪腐镰刀菌烯醇的研究

目的：利用稀土离子作为示踪剂,建立DON/ZEN双标记间接竞争时间分辨荧光免疫分析方法同时检测DON、ZEN。 方法：以DON BSA、ZEN-BSA共包被于固相微孔板,与DON/ZEN标准或样品中的DON、ZEN竞争结合抗DON多抗、抗ZEN单抗,然后分别用稀土离子Eu3+-羊抗兔IgG及Sm3+ 羊抗鼠IgG进行示踪检测,并对建立DON/ZEN-双标记TRFIA进行方法学的考核。结果：DON/ZEN-双标记TRFIA检测灵敏度,DON为0.2 ng/ml、ZEN为0.7 ng/ml,检测范围为：DON 0.2~100 ng/ml,ZEN 0.7~50 ng/ml,批内、批间变异率均小于10%。不同样品添加回收实验表明玉米、小麦样品中DON平均回收率分别为102.8%、98.8%,ZEN平均回收率分别为94.2%、95.7%。DON/ZEN-双标TRFIA检测时,DON与ZEN不相互干扰,该方法特异性好。玉米样品检测结果表明,DON/ZEN双标记TRFIA与单标记DON -TRFIA、ZEN-TRFIA试剂盒结果高度相关,具有较好的一致性,两者检测DON的结果相关系数为0.9760,检测ZEN结果的相关系数为0.9695,结论：DON/ZEN-双标记TRFIA灵敏度高,检测范围宽,重复性、稳定性好,一次检测可同时得到DON、ZEN两个结果,是一种简便、快速、经济、稳定、可进行大批量样品筛查的检测方法。     

Validation of a sensitive enzymeimmunoassay for 13,14-dihydro-15-keto-PGF2alpha in buffalo plasma and its application for reproductive health status monitoring

A simple, sensitive and direct enzymeimmunoassay (EIA) procedure on microtitre plates using the second antibody coating technique was standardized and validated for the determination of 13,14-dihydro-15-keto PGF2alpha (PGFM) in unextracted buffalo plasma. The assay was carried out directly in 20 microl of buffalo plasma. PGFM standards prepared in charcoal stripped hormone-free plasma were used. The sensitivity of the assay was 0.4 pg/well, which corresponded to 20 pg/ml plasma. Plasma volumes for the assay ranging from 10 to 50 microl did not influence the PGFM standard curve; however, a slight drop in the OD450 was observed with higher plasma volumes. Biological validation of the assay was carried out in buffalo plasma samples obtained during physiological states of cyclicity, peri-estrus, post-insemination, reproductive tract infection and persistent corpus luteum conditions. A pulsatile pattern of plasma PGFM release was observed prior to estrus when PGFM was determined in blood samples collected at hourly intervals of time. The PGFM pulsatility was not observed when blood sampling frequency of either 4 or 12 h was considered. The PGFM levels stayed high in peripheral circulation of buffaloes with reproductive tract infections and remained low throughout the sampling period in buffaloes having persistent corpus luteum. After an initial increase post-insemination, the plasma PGFM levels showed minor fluctuations. The assay was found to be sufficiently reliable and specific for estimation of PGFM levels in buffaloes. The standardization and validation of PGFM assay in buffalo opens the prospects of using PGFM levels as an indicator for reproductive health status monitoring in this species.     

Ultrasensitive green spectrofluorimetric approach for quantification of Hg(II) in environmental samples (water and fish samples) using cysteine@MnO2 dots

Mercury (Hg²⁺) is a natural element present in foods such as fish, water and soil. Exposure to mercury leads to severe toxic effects on the nervous, digestive, and immune systems. Here, a novel, green, and environmentally friendly fluorescent probe decorated with cysteine/MnO₂ quantum dots (Cys@MnO₂ QDs) was synthesized. This synthesis was carried out using a simple ultrasound technique with the aid of cysteine for fabricating Cys@MnO₂ QDs to estimate Hg levels in fish and water samples. In this morphological study, Cys@MnO₂ QDs were fully characterized using high-resolution transmission electron microscopy, zeta potential analysis, fluorescence, ultraviolet–visible and infrared spectroscopy. The fluorescence of the synthesized Cys@MnO₂ QDs was significantly quenched by gradually increasing the Hg(II) concentration. The quenching mechanism based on the Hg–S bonds strengthened the utility of the Cys@MnO₂ QDs as a novel luminescent nanoprobe. The estimation of Hg was linear in the concentration range 0.7–100.0 ng mL⁻¹ with a limit of quantitation equal to 0.30 ng mL⁻¹. The Cys@MnO₂ QDs are fluorescent probes with various benefits such as speed, ease of use, cost- effective, and being environmentally friendly; they are easily applied in food manufacturing and for public health improvement.     

NLISA versus enzyme-linked immunosorbent assay: Nanozyme-linked immunosorbent array based on platinum sub-nanocluster nanozyme for α-fetoprotein detection

Rapid and accurate identification of tumor metabolic markers is important for early tumor diagnosis and individualized treatment. Here, a stable monodisperse sub-nanometer platinum (Pt) material was developed as a highly efficient nanozyme with a specific activity of peroxidase as high as 20.86 U mg⁻¹ through the growth of in situ domain-limited Pt quantum dots via the polymer polyvinylpyrrolidone. Further, the synthesis of large quantities of Pt-loaded SiO₂ (Pt-SiO₂) was determined by silylation reaction and used for naked eye colorimetric testing of human alpha-fetoprotein (AFP). In particular, the immunization incubation process occurred in preprepared microplates. A nanozyme-based immunomodel was constructed in the presence of the target AFP, and a chromogenic reaction occurred with exogenous hydrogen peroxide and the chromogenic substrate tetramethylbenzidine. On optimization of experimental conditions, the dynamic working response range for AFP was found to be 0.05–20 ng mL⁻¹, with a limit of detection of 38.7 pg mL⁻¹. This work provides a new strategy to design efficient nanozyme-based enzyme-linked immunochromatographic platforms to meet the practical use of replacing natural enzymes.     

Determination of the retinobenzoic acid derivative Am580 in rat plasma by high-performance liquid chromatography

A specific liquid chromatographic method for the determination of 4-[[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carbonyl]amino]benzoic acid (Am580) in rat plasma is described. The procedure includes one-step isolation of the compound and the internal standard (naphtol AS) from protein precipitated with acetonitrile, resolution on a reversed-phase column (Supelcosil LC18-DB, 5 μm) with water-acetonitrile-methanol-n-butanol (45:40:14:1, v/v) containing 65 mM ammonium acetate as elution system and UV absorbance detection at 280 nm. The assay was linear over a wide range (25–5000 ng ml⁻¹) and the limit of quantitation was 25 ng ml⁻¹ using 0.2 ml of plasma. It was precise and reproducible enough for pharmacokinetic studies. Application to a preliminary disposition study in the rat indicated that Am580 was characterized by a relatively large apparent volume of distribution (1.1–1.5 l kg⁻¹) and small clearance (8.8–9.7 ml min⁻¹ kg⁻¹). Its pharmacokinetic behaviour was linear within the dose range considered (2 and 10 mg kg⁻¹, i.p.).     

A novel monoclonal antibody to Neisseria meningitidis serogroup X capsular polysaccharide and its potential use in quantitation of meningococcal vaccines

A novel murine hybridoma monoclonal antibody (MAb) was produced against the capsular polysaccharide (CP) of Neisseria meningitidis serogroup X (MenX) in order to develop a sandwich enzyme linked immunosorbent assay (ELISA) for the quantitation of the meningococcal polysaccharide. The MAb only reacted with the CP from MenX and did not react with CPs from N. meningitidis serogroups A, C, Y and W (MenA, MenC, MenY, MenW). The affinity constant (Ka) of the MAb measured by non-competitive ELISA was 7.25 × 10⁷ M⁻¹. The application of this MAb in a sandwich ELISA was demonstrated by its ability to properly quantitate three lots of an experimental meningococcal CP-based vaccine. The MAb obtained in this work could be a valuable reagent for the detection and quantitation of future meningococcal vaccines containing MenX CP.     

Simultaneous single isotope radioenzymatic assay of plasma norepinephrine,epinephrine and dopamine

Modification of the original single isotope radioenzymatic assay of Passon and Peuler (1) permits the direct and simultaneous analysis of norepinephrine, epinephrine and dopamine in plasma samples of 50 μl or less. Plasma or cerebrospinal fluid without prior extraction of catecholamines or deproteinization is added directly into a mixture of 100 μl. This catechol-O-methyl-transferase-catalyzed assay is sensitive to 1 pg (20 pg/ml of plasma) for norepinephrine and epinephrine and 6 pg (120 pg/ml) for dopamine. A rapid thin layer chromatographic separation of the three ³H-methylcatecholamines contributes to the excellent specificity of the differential assay of the three catecholamines. The differential analysis of 15–20 plasma samples can be completed easily within one day. A total assay which omits the chromatographic step and, thus, measures norepinephrine plus epinephrine at the same sensitivity can be completed in 20 samples in one-half a working day.     

Development of a time‐resolved fluorescence immunoassay for herpes simplex virus type 1 and type 2 IgG antibodies

Enzyme‐linked immunosorbent assays (ELISA) specific for anti‐HSV glycoprotein G (gG) are most commonly used in the clinical diagnosis of HSV infection. But most of them are qualitative and with narrow detection ranges. A novel time‐resolved fluoroimmunoassay (TRFIA) methodology was developed for the quantitative determination of HSV IgG in human serum. The assay was based on an indirect immunoassay format, and performed in 96‐well microtiter plates. HSV‐1 and HSV‐2 were used as the coating antigens. Eu³⁺‐labeled goat anti‐(human IgG) polyclonal antibodies were used as tracers. The fluorescence intensity of each well was measured and serum HSV IgG levels quantified against a calibration curve. The detection range of the novel TRFIA was between 5 and 500 AU/mL. Assay sensitivity was 0.568 AU/mL. The intra‐ and inter‐assay coefficients of variation were 0.59–3.63% and 3.65–6.81%, respectively. Analytical recovery, dilution tests and serum panel tests were performed using TRFIA and the results proved satisfactory. There were no statistically significant differences in sensitivity and specificity between the TRFIA and commercial ELISAs. An effective, sensitive and accurate quantitative HSV type 1 and type 2 IgG TRFIA was successfully developed and provided diagnostic value in clinical use. Copyright © 2014 John Wiley & Sons, Ltd.     

High synergistic antibacterial,antibiofilm, antidiabetic and antimetabolic activity of Withania somnifera leaf extract-assisted zinc oxide nanoparticle

Nanotechnology is currently gaining immense attention to combat food borne bacteria, and biofilm. Diabetes is a common metabolic disease affecting majority of people. A better therapy relies on phytomediated nanoparticle synthesis. In this study, W. somnifera leaf extract-assisted ZnO NPs (Ws-ZnO NPs) was synthesized and characterized. From HR-TEM analysis, it has been found that the hexagonal wurtzite particle is 15.6 nm in size and − 12.14 mV of zeta potential. A greater antibacterial effect of Ws-ZnO NPs was noticed against E. faecalis and S. aureus at 100 µg mL⁻¹. Also, the biofilm of E. faecalis and S. aureus was greatly inhibited at 100 µg mL⁻¹ compared to E. coli and P. aeruginosa. The activity of α-amylase and α-glucosidase enzyme was inhibited at 100 µg mL⁻¹ demonstrating its antidiabetic potential. The larval and pupal development was delayed at 25 µg mL⁻¹ of Ws-ZnO NPs. A complete mortality (100%) was recorded at 25 µg mL⁻¹. Ws-ZnO NPs showed least LC₅₀ value (9.65 µg mL⁻¹) compared to the uncoated ZnO NPs (38.8 µg mL⁻¹) and leaf extract (13.06 µg mL⁻¹). Therefore, it is concluded that Ws-ZnO NPs are promising to be used as effective antimicrobials, antidiabetic and insecticides to combat storage pests.

     

Detection of endogenous salsolinol in neonatal rat tissue by a radioenzymatic—thin-layer chromatographic assay

A sensitive radioenzymatic—thin-layer chromatographic assay for the quantitative analysis of the tetrahydroisoquinoline alkaloid, salsolinol, in plasma and neonatal rat tissue is described. The assay involves the enzymatic O-methylation of salsolinol by catechol-O-methyltransferase in presence of [³H] S-adenosylmethionine, and subsequent separation by thin-layer chromatography of the resultant [³H] O-methyl-salsolinol from the O-methylated derivatives of dopamine, epinephrine and norepinephrine. The method allows the detection of as little as 100 pg salsolinol per g tissue, and the accurate quantitation of as little as 100 pg/ml plasma and 500 pg/g tissue. This assay permitted the detection of trace amounts of endogenous salsolinol in neonatal rat tissue (< 500 pg/g tissue).     

Radioimmunoassays for free and conjugated trienbolone and for trienbolone acetate in bovine tissue and plasma samples.

A specific, sensitive, precise and accurate radioimmunoassay has been developed for the quantitation of the synthetic anabolic steroid trienbolone acetate (TBA) and its major metabolites, free and conjugated trienbolone (TBOH) in bovine tissues and plasma. With the extraction procedure described unspecific interference with the antigen-antibody reaction could be ruled out. The assay can significantly detect amounts of more than 40 pg TBOH and 70 pg TBA. 0.1 - 2.0 g tissue and 0.1 - 1 ml plasma are sufficient for 1 determination. Residues (range 0.1 -2.0 ng/g) were still present in calves 69 days after implantation of "Revalor" (20 mg estradiol-17beta and 140 mg TBA) with the highest concentrations found in liver and TBA could only be quantitated in fat.     

Isoquinoline-based intrinsic fluorescence assessment of erythropoiesis-stimulating agent,Roxadustat (FG-4592), in tablets: applications to content uniformity and human plasma evaluation

In the present study, a first validated and green spectrofluorimetric approach for its assessment and evaluation in different matrices was investigated. After using an excitation wavelength of 345 nm, Roxadustat (ROX) demonstrates a highly native fluorescence at an emission of 410 nm. The influences of experimental factors such as pH, diluting solvents, and different organized media were tested, and the most appropriate solvent choice was ethanol. It was confirmed that there was a linear relationship between the concentration of ROX and the relative fluorescence intensity in the range 60.0–1000.0 ng ml^−1, with the limit of detection and limit of quantitation, respectively, being 17.0 and 53.0 ng ml⁻¹. The mean recoveries % [±standard deviation (SD), n = 5] for pharmaceutical preparations were 100.11% ± 2.24%, whereas for plasma samples, they were 100.08 ± 1.08% (±SD, n = 5). The results obtained after the application of four greenness criteria, Analytical Eco-Scale metric, NEMI, GAPI, and AGREE metric, confirmed its eco-friendliness. In addition, the whiteness meter (RGB12) confirmed its level of sustainability. The International Council for Harmonisation (ICH) criteria were used to verify the developed method through the study in both spiked plasma samples and content uniformity evaluation. An appropriate standard for various applications in industry and quality control laboratories was developed.     

Antibiofilm Activity of Invasive Plants against Candida albicans: Focus on Baccharis halimifolia Essential Oil and Its Compounds

The extracts of five invasive plants were investigated for antifungal and antibiofilm activities against Candida albicans, C. glabrata, C. krusei, and C. parapsilosis. The antifungal activity was evaluated using the microdilution assay and the antibiofilm effect by measurement of the metabolic activity. Ethanol and ethanol-water extracts of Reynoutria japonica leaves inhibited 50 % of planktonic cells at 250 μg mL⁻¹ and 15.6 μg mL⁻¹, respectively. Ethanol and ethanol-water extracts of Baccharis halimifolia inhibited >75 % of the mature biofilm of C. albicans at 500 μg mL⁻¹. The essential oil (EO) of B. halimifolia leaves was the most active (50 % inhibition (IC₅₀) at 4 and 74 μg mL⁻¹against the maturation phase and 24 h old-biofilms of C. albicans, respectively). Oxygenated sesquiterpenes were the primary contents in this EO (62.02 %), with β-caryophyllene oxide as the major component (37 %). Aromadendrene oxide-(2), β-caryophyllene oxide, and (±)-β-pinene displayed significant activities against the maturation phase (IC₅₀=9–310 μ mol l⁻¹) and preformed 24 h-biofilm (IC₅₀=38–630 μ mol l⁻¹) of C. albicans with very low cytotoxicity for the first two compounds. C. albicans remained the most susceptible species to this EO and its components. This study highlighted for the first time the antibiofilm potential of B. halimifolia, its EO and some of its components.