Fiber SPR biosensor sensitized by MOFs for MUC1 protein detection.

The concentration of tumor markers is low, which needs a highly sensitive, stable and fast detection method. In this paper, we proposed and demonstrated a U-shape fiber SPR biosensor sensitized by MOFs materials. The surface of the U-shape SPR sensor was modified with MOFs materials to enhance the sensitivity, and the nucleic acid aptamer was immobilized on the sensor surface because of the biocompatibility of MOFs materials. By the high specificity of the nucleic acid aptamer, the MUC1 protein was recognized and detected. The testing results indicate that the sensor has a logarithmic linear response in the MUC1 protein concentration detection range of 1 pg/ml-100 µg/ml, its sensitivity and detection limit are 5.33 nm/log(µg/ml) and 0.16 pg/ml respectively. After being sensitized by MOFs, the detection sensitivity of the sensor can be increased by 1.62 times，the LOD can be decreased by 0.75 times. The sensor has high sensitivity and specificity, which has broad application prospects in clinical detection of tumor markers.

Twisted Fiber Optic SPR Sensor for GDF11 Concentration Detection.

There are few methods and insufficient accuracy for growth differentiation factor 11 (GDF11) concentration detection. In this paper, we designed a twisted fiber cladding surface plasmon resonance (SPR) sensor, which can achieve a high precision detection of GDF11 concentration. The new structure of the fiber cladding SPR sensor was realized by coupling the light in the fiber core to the cladding through fiber thermal fusion twisting micromachining technology; a series of functionalized modifications were made to the sensor surface to obtain a fiber sensor capable of GDF11 specific recognition. The experimental results showed when GDF11 antigen concentration was 1 pg/mL-10 ng/mL, the sensor had a detection sensitivity of 2.518 nm/lgC, a detection limit of 0.34 pg/mL, and a good log-linear relationship. The sensor is expected to play a role in the rapid and accurate concentration detection of pathological study for growth differentiation factors.

High sensitivity fiber cladding SPR strain sensor based on V-groove structure.

How to couple the light in the fiber core to the cladding is an urgent issue that need to be done for the fabrication of the fiber-cladding SPR sensor, and there is no report about the fiber SPR strain sensor. Hereby, we propose and demonstrate a high sensitivity fiber cladding SPR strain sensor based on V-groove structure. By CO2 laser, the V-groove is fabricated on the single-mode fiber, and the light in the fiber core is effectively coupled to the cladding. The cladding 2cm behind the V-groove is coated with sensing gold film, and a multimode fiber is spliced with the sensing probe to construct the novel fiber cladding SPR sensor. On the basis of the investigation of the effects of different V-groove depth, number and period on the performance of fiber SPR refractive index sensor, a high sensitivity strain SPR sensor is designed and fabricated by employing the characteristic that the V-groove will deform with strain. The testing results indicate that the average refractive index sensitivity of the sensor is 2896.4nm/RIU, and the strain wavelength sensitivity is 25.92pm/µÎµ which is much higher than that of the fiber interference and grating strain sensors, and the strain light intensity sensitivity is -4.4×10-4 a.u./µÎµ. The proposed fiber cladding SPR strain sensor has the advantages of simple structure and convenient manufacture, and can be used for working in a narrow space.

Multi-channel curvature sensor based on fiber bending loss wavelength and SPR.

Fiber Bragg gratings and interferometric curvature sensors are easily disturbed by axial strain and temperature, and cascaded multi-channel curvature sensing is difficult. In this letter, a curvature sensor based on fiber bending loss wavelength and the surface plasmon resonance (SPR) mechanism is proposed, which is insensitive to axial strain and temperature. In addition, fiber bending loss valley wavelength demodulation curvature improves the accuracy of bending loss intensity sensing. Experiments show that the bending loss valley of single-mode fiber with different cut-off wavelengths has different working bands which is combined with a plastic-clad multi-mode fiber SPR curvature sensor to realize a wavelength division multiplexing multi-channel curvature sensor. The bending loss valley wavelength sensitivity of single-mode fiber is 0.8474 nm/m-1, and the intensity sensitivity is 0.0036 a.u./m-1. The resonance valley wavelength sensitivity of the multi-mode fiber SPR curvature sensor is 0.3348 nm/m-1, and the intensity sensitivity is 0.0026 a.u./m-1. The proposed sensor is insensitive to temperature and strain, and the working band is controllable, which provides a new, to the best of our knowledge, solution for wavelength division multiplexing multi-channel fiber curvature sensing.

All-fiber SPR microfluidic chip for GDF11 detection.

In order to perform microfluidic detection of cytokines with low concentration, such as growth differentiation factor 11 (GDF11), the most common method is to construct microfluidic channels and integrate them with SPR sensing units. In this paper, we proposed a novel all-fiber SPR microfluidic chip for GDF11 detection. The method was to construct the SPR sensing area on a designed D-shaped multimode fiber, which was nested inside a quartz tube to form a semi-cylindrical microfluidic channel. The surface of the SPR sensing area experienced sensitization and specifically modification to achieve the specific detection of GDF11. When the sensitivity of detection was 1.38 nm/lg(g/mL) and the limit of detection was 0.52 pg/mL, the sample consumption was only 0.4 µL for a single detection. The novel all-fiber SPR microfluidic detection chip has the advantages of flexible design, compact structure and low sample consumption, which is expected to be used in wearable biosensing devices for real-time online monitoring of trace cytokines in vivo.

Dual-channel fiber surface plasmon resonance sensor based on a metallized core.

We propose a novel dual-channel fiber surface plasmon resonance (SPR) sensor based on a metalized core. Using a polymer, the cladding and coating layer of the sensor coated with a metal sensing film are restored. The parameters of the sensor are determined after studying the influence of different polymers and sensing films on the dynamic range and sensing sensitivity. A silver film coated with UV-curable adhesive and a gold film coated with polydimethylsiloxane (PDMS) with respective sensing sensitivities of up to 1.39 and 1.48 nm/°C are selected after optimization to construct the dual-channel sensor. A dual-channel fiber SPR temperature compensation refractive index sensor with improved accuracy is then constructed with a 20-nm gold film for the refractive index sensing unit and a 50-nm gold film coated with PDMS for the temperature sensing unit. Owing to its complete fiber structure, the SPR sensor has good mechanical properties and high practical value, and it can be easily applied to real-time temperature measurements and temperature compensation in various fields.

Microscope-assisted anterior cervical discectomy and fusion combined with posterior minimally invasive surgery through tubular retractors for multisegmental cervical spondylotic myelopathy: A retrospective study.

This study aimed to investigate the clinical efficacy and outcome of combined microscope-assisted anterior cervical discectomy and fusion (ACDF) with posterior minimally invasive surgery through tubular retractors for patients with multisegmental cervical spondylotic myelopathy (MCSM).This retrospective study included 28 patients (19 males and 9 females) with multisegmental cervical spondylotic myelopathy, who underwent combined microscope-assisted ACDF with posterior minimally invasive surgery through tubular retractors in our single center between January 2012 and December 2016. The evaluated postoperative clinical outcomes were operation time, length of hospitalization, blood loss, levels of creatine phosphokinase isoenzyme MM (CPK-MM), Japanese Orthopedic Association (JOA) scores, visual analogue scale (VAS) scores, Cobb angle of C2-C7, and radiological assessments (included X-rays, computed tomography scans, and magnetic resonanceimaging images).The mean surgery time was 198.42 ±â€Š17.53 minutes, the average hospitalization length of hospital was 7.59 ±â€Š1.38 days, and the mean follow-up time was 13 ±â€Š2.45 months. On average, about 36.42 ±â€Š10.15 mL of blood was lost and CPK-MM increased to 331.75 ±â€Š23.15 IU/mL postoperatively (P < .001). The mean modified JOA scores increased from 8.21 ±â€Š0.69 preoperatively to 13.96 ±â€Š1.57 postoperatively (P < .001), whereas the mean VAS scores decreased from 6.64 ±â€Š1.28 preoperatively to 0.39 ±â€Š0.50 postoperatively (P < .001). Cobb angle of C2-C7 increased from 13.86°â€Š±â€Š5.69° preoperatively to 14.10°â€Š±â€Š5.56° postoperatively (P = .16).In conclusion, combined microscope-assisted ACDF with posterior minimally invasive surgery through tubular retractors appears to be a safe and effective treatment for patients with MCSM.

Primary spinal glioblastoma multiforme: A case report and review of the literature.

RATIONALE: Primary spinal glioblastoma multiforme (GBM) is a rare clinical entity with an aggressive course and an invariably dismal prognosis. Its clinical characteristics, radiologic and pathologic findings, and treatment protocols have been discussed in a few cases. PATIENT CONCERNS: A 15-year-old female was admitted to the neurology department with a chief complaint of progressive numbness and weakness in her left upper extremity for 3 months and neck pain for 1 month. DIAGNOSES: Spinal magnetic resonance imaging showed an intramedullary expansile mass localized between C4 and C7. The diagnosis of GBM was determined on the basis of the histopathological findings after operation. INTERVENTIONS: Laminotomy and laminoplasty between C4 and C7 were performed, and the tumor was partially resected. The patient was administered focal adjuvant radiotherapy concomitantly with oral chemotherapy following the surgery. OUTCOMES: With severe neurologic deficits at 13 months after the diagnosis, the patient expired. LESSONS: Although therapeutic options have been improving, the prognosis of the primary spinal GBM remains poor. The treatment of primary spinal GBM entered into a central registry and multiple-center cooperation is important in establishing future therapeutic strategies.