Effect of acupuncture on tic disorder: a randomized controlled clinical trial based on energy metabolomics and infrared thermography.

BACKGROUND: Acupuncture is a method for treating tic disorder. However, there is a lack of sufficient clinical objective basis in regards of its treatment efficacy. Indeed, there are structural abnormalities present in energy metabolism and infrared thermography in children with tic disorder. Therefore, this study proposes a clinical trial scheme to explore the possible mechanism of acupuncture in treating tic disorder. METHODS: This randomized controlled trial will recruit a total of 90 children, in which they will be divided into non-intervention group and intervention group. The non-intervention group consists of 30 healthy children while the intervention group consists of 60 children with tic disorder. The intervention group will be randomly allocated into either the treatment group or the control group, with 30 children randomly assigned in each group. Children either received acupuncture treatment and behavioral therapy (treatment group) or sham acupuncture treatment and behavioral therapy (control group), 3 treatment sessions per week for a period of 12 weeks, with a total of 36 treatment sessions. Outcome measures include YGTSS, urinary and fecal metabolomics, infrared thermography of body surface including governor vessel. For the intervention group, these outcome measures will be collected at the baseline and 90th day prior to intervention. Whereas for the non-intervention group, outcome measures (excluding YGTSS) will be collected at the baseline. DISCUSSION: The main outcome will be to observe the changes of the severity of tic condition, the secondary outcome will be to observe the changes of structural characteristic of infrared thermography of body surface/acupoints along the governor vessel and to evaluate the changes of urinary and fecal metabolomics at the end of the treatment, so as to analyze the relationship between them and to provide further knowledge in understanding the possible mechanism of acupuncture in improving the clinical symptoms via regulating and restoring the body metabolomics network, which in future it can develop as a set of clinical guideline (diagnosis, treatment, assessment, prognosis) in treating tic disorder. ChiCTR2300075188(Chinese Clinical Trial Registry, http://www.chictr.org.cn , registered on 29 August 2023).

A review on chitosan/metal oxide nanocomposites for applications in environmental remediation.

A cleaner and safer environment is one of the most important requirements in the future. It has become increasingly urgent and important to fabricate novel environmentally-friendly materials to remove various hazardous pollutants. Compared with traditional materials, chitosan is a more environmentally friendly material due to its abundance, biocompatibility, biodegradability, film-forming ability and hydrophilicity. As an abundant of -NH2 and -OH groups on chitosan molecular chain could chelate with all kinds of metal ions efficiently, chitosan-based materials hold great potential as a versatile supporting matrix for metal oxide nanomaterials (MONMs) (TiO2, ZnO, SnO2, Fe3O4, etc.). Recently, many chitosan/metal oxide nanomaterials (CS/MONMs) have been reported as adsorbents, photocatalysts, heterogeneous Fenton-like agents, and sensors for potential and practical applications in environmental remediation and monitoring. This review analyzed and summarized the recent advances in CS/MONMs composites, which will provide plentiful and meaningful information on the preparation and application of CS/MONMs composites for wastewater treatment and help researchers to better understand the potential of CS/MONMs composites for environmental remediation and monitoring. In addition, the challenges of CS/MONM have been proposed.

Adsorptive removal of anionic azo dye by Al3+-modified magnetic biochar obtained from low pyrolysis temperatures of chitosan.

Magnetic γ-Fe2O3/Al3+@chitosan-derived biochar (m-Fe2O3/Al3+@CB) was prepared by introducing magnetic maghemite (γ-Fe2O3) nanoparticles and aluminum sulfate [Al2(SO4)3] into chitosan-derived biochar (CB) obtained at low pyrolysis temperatures. m-Fe2O3/Al3+@CB was used to remove typical anionic azo dye (Congo red, CR). Effects of initial CR concentration, contact time, initial pH value, background electrolytes, and temperature on CR adsorption by m-Fe2O3/Al3+@CB were studied. Compared with magnetic chitosan-derived biochar (m-Fe2O3@CB), m-Fe2O3/Al3+@CB exhibited excellent performance for a wider range of pH values (pH 1-7) and in the presence of background electrolyte. The introduction of Al3+ is an effective method for improving the properties of magnetic chitosan-derived biochar. High CR adsorption capacity (636.94 mg g-1) of m-Fe2O3/Al3+@CB could result from collaborative effect of flocculation/coagulation and electrostatic attraction. These results demonstrated that m-Fe2O3/Al3+@CB is a potential adsorbent for effective removal of organic dyes from aqueous solution due to its high adsorption capacity and convenient magnetic recovery and stronger anti-interference ability against coexisting anions in wastewater.

Magnetic Fe3O4 embedded chitosan-crosslinked-polyacrylamide composites with enhanced removal of food dye: Characterization, adsorption and mechanism.

The water solubility in acid solution, relative low adsorption capacities and unsatisfactory separation performance limit application of traditional chitosan-based adsorbents in wastewater treatment. To break the limitation, a hydrophilic magnetic Fe3O4 embedded chitosan-crosslinked-polyacrylamide composites (abbreviated as m-CS-c-PAM) were prepared by a two-step method. The m-CS-c-PAM composites were systematically characterized using SEM, XRD, FTIR, VSM, TGA and BET. Sunset yellow (SY) was selected as model food dye to investigate adsorption kinetics and thermodynamic parameters of food dye adsorption onto m-CS-c-PAM. Compared with magnetic Fe3O4/chitosan, m-CS-c-PAM can adapt to a wider range of pH (2-10) and resist the presence of inorganic salts. m-CS-c-PAM was proved to have high adsorption capacity (359.71 mg g-1) for SY dye at 298 K, much higher than magnetic Fe3O4/chitosan and many reported adsorbents. Moreover, m-CS-c-PAM could be rapidly and efficiently separated from treated solution within 15 s by an external magnet and regenerated by NaOH solution. With its excellent adsorption capacity, pH-independent adsorption capability for food dye, easy and convenient separation ability, satisfactory reusability, m-CS-c-PAM can be a promising material for food wastewater treatment.

[Professor SHENG Can-ruo's experience of acupuncture for chronic pelvic pain of sequelae of pelvic inflammatory diseases].

Professor SHENG Can-ruo proposes that the pathogenesis of chronic pelvic pain of sequelae of pelvic inflammatory diseases is "kidney deficiency and cold coagulation, obstruction of the governor vessel and the belt vessel". For the treatment, attention is paid to warming yang and tonifying kidney, dredging and regulating the governor vessel and the belt vessel; the acupoints of Sanyinjiao (SP 6), Fuliu (KI 7), Taixi (KI 3) etc. are selected. With the method of treating yang for yin disorder and mao-acupuncture, professor SHENG emphasizes the importance of syndrome differentiation-based treatment. The main point of treatment is to balance yin-yang and to maintain both sides of the symptoms and root causes.

[Effect of acupuncture combined with rehabilitation training on cognitive function and amino acid metabolism in children with cerebral palsy].

OBJECTIVE: To observe the effect of acupuncture combined with rehabilitation training on cognitive function and amino acid metabolism in children with cerebral palsy. METHODS: Twenty children with cerebral palsy (cerebral palsy group) were randomly divided into an acupuncture and rehabilitation group (11 cases) and a rehabilitation group (9 cases), and 10 healthy children were included as the normal group. The rehabilitation group was treated with rehabilitation training, 30 min each time; on the basis of rehabilitation training, the acupuncture and rehabilitation group was treated with acupuncture at Sishenzhen, Zhisanzhen, Naosanzhen, Niesanzhen, Dazhui (GV 14), Shenzhu (GV 12), Mingmen (GV 4), etc. The Sishenzhen (left and right points) and the ipsilateral Niesanzhen were respectively connected with a group of electrodes, intermittent wave, frequency of 2 Hz for 30 min. Both groups were treated once every other day, three times a week, totaling for 3 months. The Gesell developmental diagnostic scale (GESELL) was used to evaluate the developmental quotient (DQ) scores before and after treatment, and the blood samples of children with cerebral palsy before and after treatment and normal children were collected for amino acid metabolomics. RESULTS: Compared before treatment, the DQ scores of adaptation, fine motor and social in the acupuncture and rehabilitation group was increased after treatment (P<0.05), and the DQ score of fine motor in the rehabilitation group was increased after treatment (P<0.05). Compared with the normal group, the serum L-glutamate, L-ornithine, L-tyrosine, L-methionine and L-arginine in the cerebral palsy group were down-regulated, and L-histidine, L-citrulline, 5-hydroxylysine and L-glutamine were up-regulated before treatment. The functional pathways mapped by different metabolites between the cerebral palsy group and the normal group included arginine biosynthesis, arginine and proline metabolism, etc. Compared with the cerebral palsy group, the serum L-histidine was decreased, and L-citrulline showed decreasing trend in the acupuncture and rehabilitation group after treatment. CONCLUSION: Acupuncture combined with rehabilitation training could improve cognitive function in children with cerebral palsy, and the effect may be related to the down-regulation of L-histidine and L-citrulline metabolism.

[Professor WU Xu's experience in treatment of tic disorders in children with acupuncture from "meridian tendons"].

Professor WU Xu believes that the pathogenesis of tic disorders in children is "agitation of liver wind, lending to excessive wind and spasm of tendons" "deficiency of yin fluid, the tendons failing to be nourished" "spirit failing to govern, leading to tendons not be restrained" and advocates to treat this disease from the theory of "meridian tendons". He suggests the acupoints that related to "meridian tendons", and emphasizes the depth of needling and the procedure of acupuncture, and believes that the core of treating is to balance the yin and yang of "meridian tendons" and regulate spirit.

[Professor WU Xu's clinical experience of acupuncture for alternating hemiplegia of childhood].

Professor WU Xu's clinical experience of acupuncture for alternating hemiplegia of childhood is summarized. Based on the syndrome differentiation of meridians and the theory of zangfu, professor WU proposes that the etiology and pathogenesis is "three yin as the root causes, deficiency wind as the symptoms", and the treatment is to tonify deficiency and reinforce the vital essence, soothe the liver and relieve wind. The acupoints used is mainly in the foot three yin meridians, paying attention to tonifying the kidney; the combinations of Hegu (LI 4) and Taichong (LR 3), Fengmen (BL 12) and Fengshi (GB 31) are adopted; combined with the back-shu points and the governor vessel acupoints, professor WU emphasizes "harmonizing yin and yang" and "treating and nourishing the spirit".

Vitreoretinal surgeons' experience and time interval from pars-plana vitrectomy to cataract extraction.

AIM: To identify the association of the vitreoretinal surgeons' experience with the time interval between pars-plana vitrectomy (PPV) and cataract extraction (CE). METHODS: Eyes with prior PPV and following CE were included in this retrospective cohort study. The years of practice and the annual case volume were used to describe the surgeons' experience. Multivariable linear regression analysis was used to investigate the relationship between surgeons' experience and the time interval adjusted for the patients age, gender, intraocular tamponade, and case complexity. RESULTS: Of 132 430 eyes, 1445 eyes were included in this study. In multivariable linear regression analysis, cases performed by surgeons with >20 practice years had longer time intervals compared with surgeons with <10 practice years after adjusted for other variables (ß=0.329, 95%CI: 0.113 to 0.549, P=0.003). No difference in time interval was detected for comparing the lowest with the highest volume groups (ß=0.089, 95%CI: -0.164 to 0.343, P=0.343). The surgeons' practice years were not directly with the volume. For complicated surgery, the higher-practice-year surgeons had longer time interval than lower-practice-year surgeons. CONCLUSION: The time intervals from PPV to CE is longer in higher-practice-year surgeons. The surgeons' practice years may have a greater effect on the time interval than annual case volume in high-complexity cases. Matching the complexity of vitreoretinal diseases with the surgeons' practice year should be considered.

Magnetic NiFe2O4/MWCNTs functionalized cellulose bioadsorbent with enhanced adsorption property and rapid separation.

Magnetic NiFe2O4 nanoparticles and multi-walled carbon nanotubes functionalized cellulose composite (m-NiFe2O4/MWCNTs@cellulose) as a magnetic bioadsorbent was prepared and used for effectively removing Congo Red (CR) from aqueous solution. The chemical and physical properties of the prepared m-NiFe2O4/MWCNTs@cellulose were characterized by XRD, TGA, FT-IR, VSM, SEM and TEM. Batch experiments were carried out to investigate the adsorption capacity and mechanisms. Effects of different adsorption parameters such as initial CR concentration, adsorbent dosage and temperature were studied. Results demonstrated that m-NiFe2O4/MWCNTs@cellulose had high adsorption capacity for CR from aqueous solution. The obtained experimental data fitted well with the pseudo-second-order equation and followed the Langmuir isotherm model with a maximum adsorption capacity of 95.70 mg g-1 for CR. The m-NiFe2O4/MWCNTs@cellulose with rapid magnetic separation and high adsorption capacity can be a promising and recyclable engineering biomaterials for purification and treatment of practical wastewater.

Accuracy of eight intraocular lens power calculation formulas for segmented multifocal intraocular lens.

AIM: To evaluate the accuracy of eight different intraocular lens (IOL) power calculation formulas for a segmented multifocal IOL. METHODS: A total of 53 eyes of 41 adult cataract patients who underwent phacoemulsification and implantation with the SBL-3 segmented multifocal IOL between January 1, 2017 and January 31, 2019 were included in this retrospective study. Preoperative biometry measurements were obtained using an IOL Master. Manifest refraction was performed at least 4wk postoperatively. Accuracy of the eight formulas [Barrett Universal II, Emmetropia Verifying Optical (EVO), Haigis, Hill-RBF 2.0, Hoffer Q, Holladay 1, Kane, and SRK/T] was analyzed. RESULTS: Using current lens constants, all formulas exhibited errors of slight myopic shift in refractive prediction. The Barrett Universal II formula had a significantly lower median absolute error (MedAE) than did Holladay 1 (P=0.02), Kane (P=0.001) and Hill-RBF 2.0 (P<0.001) formulas. The Haigis formula had a lower MedAE value than did the Hill-RBF 2.0 formula (P=0.005). Differences in MedAE values among SRK/T, EVO and Hoffer Q formulas were not significant. After optimizing lens constants, the MedAE values of all formulas were reduced; significant changes were noted for EVO (P=0.022), Haigis (P=0.048), Hill-RBF 2.0 (P=0.014), Holladay 1 (P=0.045) and Kane (P=0.022) formulas. All formulas performed equally well after optimization of lens constants (P=0.203). CONCLUSION: All eight formulas tend to result in a myopic shift when using current lens constants. Optimized lens constants improve the accuracy of these formulas among adult Chinese patients.

Scaphoid metastasis as the first sign of occult gastroesophageal junction cancer: A case report.

BACKGROUND: Metastatic tumors of the hand are very rare. They are usually late manifestations of massive advanced malignancies. However, a small portion of acrometastases are indications of occult primary cancer. Here, we report an extremely rare case in which a scaphoid bone lesion was the initial manifestation and was found to be a metastasis from gastroesophageal junction (GEJ) cancer. CASE SUMMARY: A 57-year-old male patient presented with ongoing left wrist pain and swelling after trauma. He was initially misdiagnosed with infection of the scaphoid bone and treated with antibiotics and anti-inflammatory drugs. Further radiographic investigations showed a scaphoid pathological fracture, indicating a metastatic tumor derived from the GEJ and/or right lung malignancies. Gastroscopy failed to identify the pathology of the mass at the GEJ, which grew in an exophytic pattern. A lung puncture biopsy was not performed because the patient refused the procedure. To relieve his wrist pain and obtain a definite pathology, we resected the scaphoid lesion. Based on the clinical and pathological results, the patient was finally diagnosed with multiple metastases of advanced GEJ adenocarcinoma. He underwent chemotherapy and died 6 mo after his initial presentation. CONCLUSION: Despite the rareness of the disease, orthopedic surgeons should consider the possibility of metastasis to the bones of the hand when patients complain of persistent and progressive pain in the hand.

Abnormal alterations of miR-1 and miR-214 are associated with clinicopathological features and prognosis of patients with PDAC.

Pancreatic ductal adenocarcinoma (PDAC) is a devastating malignant disease with a poor prognosis. PDAC is known to be difficult to diagnose at an early stage and to exhibit poor recurrence-free prognosis, but there is also a lack of effective treatment and limited knowledge of its biological characteristics. Therefore, there is an urgent requirement for an improved understanding of the cellular or molecular properties associated with PDAC, and to explore novel avenues for the diagnosis and treatment of this disease. In the present study, the microRNA (miRNA/miR) profiles of sera and tumor samples from patients with PDAC and healthy controls were investigated by miRNA microarray, and the potential role of miR-1 expression in PDAC was determined. A total of 43 patients attending the clinic diagnosed with PDAC at Changzhi City People's Hospital were invited to participate. Blood and surgical tumor samples were obtained for analysis by miRNA microarray and the reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The surgical tumor tissue was additionally used to determine miRNAs status by in situ hybridization (ISH). The results of microarray revealed that: i) 27 miRNAs in the sera and 23 miRNAs in the tumor tissues obtained from patients with PDAC were different compared with their matched controls; ii) miR-1, miR-10b and miR-214 were significantly altered in the PDAC group, either in the sera or tumor tissue samples. Results from the RT-qPCR, which detected the levels of miRNAs in patients with PDAC, confirmed those obtained from the miRNA microarray. In particular, the results of the present study revealed that decreased miR-1 and increased miR-214 in the PDAC tissues were associated with the clinicopathological features and survival rates of patients with PDAC. The results of the present study indicated that miRNAs serve an important role in PDAC carcinogenic progression and supplied useful markers, including miR-1, miR-214 and miR-10b, for determining PDAC prognosis using noninvasive methods.

[Professor WU Xu's clinical experiences on acupuncture for acute upper abdominal pain].

The clinical experiences and proven cases of distinguished doctor of TCM, professor WU Xu, on acupuncture for acute upper abdominal pain is introduced. Professor WU's manipulation characteristics of acupuncture for acute upper abdominal pain, including acute cholecystitis, kidney stone, acute stomach pain, are one-hand shape but both hands in nature, moving like Tai Chi, force on the tip of needle, movement of qi mainly. The main technique posture is one-hand holding needle with middle finger for pressing, the needle is hold by thumb and index finger, and is assisted by middle finger. The special acupuncture experience of emergency is treatment according to syndrome differentiation, combination of acupuncture and moxibustion, selecting acupoint based on experience, blood-letting acupuncture therapy and so on.

Effect of dirhamnolipid on the removal of phenol catalyzed by laccase in aqueous solution.

In this study, the effects of three surfactants, i.e. the anionic biosurfactant dirhamnolipid (diRL), the cationic surfactant hexadecyltrimethyl ammonium bromide (CTAB), and the anionic surfactant sodium dodecyl sulfate (SDS), on the removal of phenol catalyzed by laccase were studied first. CTAB and SDS were detrimental, while diRL improved phenol removal and was selected for detailed research. The biosurfactant increased the activity of laccase and the removal of phenol with the increase of diRL concentrations from 10.6 to 318 µM. DiRL at 318 µM improved the removal when the initial concentrations of phenol were from 50 to 400 mg/l. In particular, the removal of phenol with 318 µM diRL was 4.3-6.4 folds that of the controls within 24 h when the initial concentration of phenol was 400 mg/l. The presence of diRL at 318 µM also caused the complete removal (above 98%) of phenol at concentrations from 50 to 400 mg/l after 24 h. The enhancement of phenol removal was over a wide range of pH and temperatures, and the highest removal efficiency was obtained at pH 6.0 and 50°C. The results suggest that diRL had potential application in the enhancement of phenols removal catalyzed by laccase in water treatment or remediation.

Comparison of percutaneous compression plating and short reconstruction nail for treatment of intertrochanteric fracture.

OBJECTIVE: To compare percutaneous compression plating (PCCP) with Trigen short reconstruction nail (Trigen SRN) for the treatment of intertrochanteric hip fracture. METHODS: Eighty-four patients with intertrochanteric hip fracture admitted to our hospital from January 2007 to June 2008 were included in this retrospective study. Thirty-six patients were treated with PCCP and 48 with Trigen SRN. Information regarding age, surgical time, blood loss, length of follow-up, mortality, fracture impaction, time to union, complications, Harris score and visual analog scale (VAS) were all recorded. RESULTS: The mean follow-up time was 16.3 ± 3.2 months (13-19 months). The mean time to achieve radiological fracture healing was 3.6 ± 0.8 and 4.1 ± 1.0 months for the PCCP and Trigen SRN groups, respectively (P= 0.020); the mean Harris hip scores were 78.1 ± 4.8 and 74.1 ± 5.2 (P= 0.001); and the mean fracture impaction was 3.6 ± 2.3 and 3.3 ± 2.6 mm (P= 0.023). There were no statistical differences between the two groups in duration of surgery (P= 0.131) and blood loss (P= 0.268). The amount of nail in the inferior-central quadrants was greater in the PCCP group than in the Trigen SRN group. CONCLUSION: PCCP achieves earlier pain release and better fracture reduction than Trigen SRN.

[Observation on effective characteristics of acupuncture combined with medicine on depression of different syndrome types].

OBJECTIVE: To evaluate and analyze the clinical therapeutic effect and characteristics of acupuncture combined with medicine on depression of different syndrome types. METHODS: Eighty cases of depression were dividede into liver qi stagnation and spleen deficiency group (group A, 35 cases), deficiency of both heart and spleen group (group B, 21 cases) and yang deficiency of both spleen and kidney group (group C, 24 cases) according to the syndrome differentiation. They were all treated with acupuncture at Baihui (GV 20), Yintang (EX-HN 3), Sishen-cong (EX-HN 1), Neiguan (PC 6) etc. and oral administration of 5-HT selective serotonin reuptake inhibitors (SSRI) tablets. The Hamilton depression scale (HAMD) and self-made syndrome differentiation symptoms evaluation scale were adopted to evaluate the therapeutic effect. RESULTS: After treatment of 4 weeks, the total effective rate of 91.4% in group A and of 90.5% in group B, both were superior to that of 87.5% in group C (P < 0.01,P<0. 05). There was a significant difference in comparison of HAMD scores between the group A and group C after treatment of 4 weeks (P < 0.05). The symptom scores of syndrome differentiation in all three groups were obviously decreased after 1 week, 2 weeks and 4 weeks treatment compared with those before treatment (all P < 0.001), the symptom scores of group C had significant differences compared with the group A and group B after treatment of 2 weeks (P < 0.01, P < 0.05). The reducing scores rate of the group A had singificant differences compared with the group B and the group C after treatment of 4 weeks (both P < 0.05). CONCLUSION: Acupuncture combined with SSRI has better therapeutic effect on depression of liver qi stagnation and spleen deficiency type. The syndrome differentiation symptoms evaluation scale is more exact and sensitive to evaluate the clinical therapeutic effect of TCM treatment.

[Treatment of acute and chronic osteomyelitis with negative pressure wound therapy].

OBJECTIVE: To investigate the treatment of acute and chronic osteomyelitis with negative pressure wound therapy. METHOD: Thirty cases of acute and chronic osteomyelitis were treated with negative pressure wound therapy, assisted with debridement, autodermoplasty and myo-cutaneous flap surgery. RESULTS: No evidence of relapse was found in all cases treated with negative pressure wound therapy. All the patients were followed up, range from 6 to 23 months, the average was 13.6 months. CONCLUSION: The negative pressure wound therapy maybe a simple, effective and inexpensive method, and could be one of the favorable therapy in the treatment of acute and chronic osteomyelitis.

The accumulation of nonylphenol in a wastewater recycling process.

A mathematical model was developed in this paper to describe the nonylphenol (NP) accumulation in the effluent of a wastewater recycling system. The model quantitatively presented the relationships among the NP concentrations in the raw wastewater and the system effluent, the number of wastewater recycling cycles, the water recycling ratio, the system NP removal efficiency, and the NP accumulation factor. The mathematical model was then verified through experimental modeling of a wastewater recycling process, and it was indicated that the Pearson correlation coefficient between mathematical simulation and experimental modeling results was 0.652. The study results indicated that the NP accumulation factor of a wastewater recycling system would approach a constant for large number of wastewater recycling cycles given the wastewater recycling ratio and system NP removal efficiency. The results also revealed that the NP concentration in the effluent increased with the wastewater recycling ratio given the system NP removal efficiency, and the increase of NP removal efficiency would decrease the NP accumulation in the system effluent under a given wastewater recycling ratio condition. The model was then applied to compute the maximum wastewater recycling ratio, predict reclaimed water quality and direct the design and management of sewage recycling systems in China.

[Catechol biosensor based on immobilizing laccase to modified core-shell magnetic nanoparticles supported on carbon paste electrode].

A catechol biosensor was developed and used to analyze compost extracts based on the immobilization of laccase on the surface of modified magnetic core-shall (Fe3O4-SiO2) nanoparticles. Laccase was convalently immobilized on the magnetic nanoparticles by glutaraldehyde, which were modified with amino groups on its surface. The resulting magnetic bio-nanoparticles were attached to the surface of carbon paste electrode with the help of a permanent magnet to determine catechol. The immobilization matrix provided a good microenvironment for retaining the bioactivity of laccase. The linear range for catechol determination was 7.5 x 10(-7)-2.75 x 10(-4) mol/L, with a detection limit of 7.5 x 10(-7) mol/L. The detection current reached 95% of the steady-state current within about 70 s. Catechol concentration in compost extracts were determined by laccase biosensor and HPLC, with approximately the same result.