Yang Ran

Jinan University · Institute of Photonics Technology

Efficient delivery of photons to visceral organs is critical for the treatment of deep‐seated tumors taking advantage of photo theranostics. Optical fiber can be regarded as a direct and facile photon pathway for targeting tumor lesion. However, current fiber theranostic strategies rely on the spatially separated optical fibers to realize diagnosis...

In this work, we proposed, for what we believe to be the first time, a wearable optical sensor based on the higher-order harmonic fiber Bragg grating (FBG), which has the advantages of easy fabrication, visible window operation and cross-talk removal. The fifth-order harmonic Bragg grating was inscribed by use of the conventional C-band phase masks...

Chemotherapy is one of the conventional treatments for cancer in clinical practice. However, poor delivery efficiency, systemic toxicity, and the lack of pharmacokinetic monitoring during treatment are the critical limitations of current chemotherapy. Herein, we reported a brand-new antitumor drug delivery strategy that harnesses an optical fiber e...

The movement of ions along the pressure-driven water flow in narrow channels, known as downstream ionic transport, has been observed since 1859 to induce a streaming potential and has enabled the creation of various hydrovoltaic devices. In contrast, here we demonstrate that proton movement opposing the water flow in two-dimensional nanochannels of...

This article presents the distinctive butyrylcholinesterase (BChE) fluorescent probe P5, designed via a targeting-site method. This method was proposed to enhance the affinity of the probe for BChE by targeting the peripheral anionic site (PAS) of BChE. By mimicking the natural substrate butyrylcholine, the structure of the probe was optimized by i...

Efficient delivery of photons to visceral organs is critical for the treatment of deep-seated tumors taking advantage of photo-theranostics. Optical fiber can be regarded as a direct and facile photon pathway for targeting tumor lesion with negligible body invasion. However, current fiber theranostic strategies rely on the spatially separated optic...

Cancer has been one of the most serious diseases, resulting in more than 10 million deaths every year. Fiber-optic sensors have great potential for diagnosing and treating cancer due to their flexibility, precise positioning, real-time monitoring, and minimally invasive characteristics. Compared to traditional central laboratory examination, fiber-...

The illegal water injection into meat not only breaks the market equity, but also deteriorates the meat quality and produces harmful substances. In this work, we proposed a fiber Bragg grating (FBG) sensor that enabled fast, quantitative, and in-situ detection of the moisture content of water-injected meat. The FBG was written in the erbium-ytterbi...

Optical fiber-based photothermal devices show great promise for applications in in vivo detection and therapy. The integration of sensors and actuators in one fiber is a feasible method to orchestrate both functionalities. However, the photoheating-induced temperature field is not always homogeneous in the practical application, which undermines th...

Flexibly wearable sensors are widely applied in health monitoring and personalized therapy. Multiple-node sensing is essential for mastering the health condition holistically. In this work, we report a multi-node wearable optical sensor (MNWOS) based on the cascade of microfiber Bragg gratings (µFBG), which features the reflective operation mode an...

Tapered microfiber grating (μFBG) has significant applications in biosensing and medical diagnostics, yet its complexed chirp spectrum still required manual demodulation. Herein, we present a spectral demodulation method for the tapered microfiber grating based on the MobileNet convolutional neural network. Compared to five classical convolutional...

Fiber-optic grating biosensor offers compelling advantages such as compact footprint and nature of signal reflection, and thus becomes a particularly apt candidate for cardiovascular biomarker determination. However, limit of detection (LOD), test speed, and maneuverability of such biosensor should be substantially improved before conferring those...

Detection of trace tumor markers in blood/serum is essential for the early screening and prognosis of cancer diseases, which requires high sensitivity and specificity of the assays and biosensors. A variety of label-free optical fiber-based biosensors has been developed and yielded great opportunities for Point-of-Care Testing (POCT) of cancer biom...

Fiber-optic devices working in the visible and near-infrared windows are attracting attention due to the rapid development of biomedicine that involves optics. In this work, we have successfully realized the fabrication of near-infrared microfiber Bragg grating (NIR-µFBG), which was operated at the wavelength of 785 nm, by harnessing the fourth har...

Wearable sensing devices, which can find tremendous applications in healthcare and automation, are attracting great attention in recent years. Herein, we report a flexible wearable optical sensor (FWOS) which consists of the microfiber Bragg grating (μFBG) as the core sensing node and a ductile PDMS film as the sensor encapsulation. Due to the stra...

Accurate and timely assessment of malignant tumor in the early stage and therapy process is critical for making clear guidance and prognosis for the treatment, which can significantly elevate the cure rate of cancer patients. Fluorescent sensing and imaging of tumor have attracted extensive attention because of their advantages of high sensitivity...

Photothermal actuation that leverages optical fiber and plasmonic materials would not only add a practical function but also spur many important applications for the fiber-optic sensors, for example, the self-temperature governing and fiber-optic photothermal medicine probe. In this paper, we propose and demonstrate a microfiber Bragg grating devic...

A micro-nanostructure-based surface-modified fiber-optic sensor has been developed herein to selectively detect hydrogen peroxide (H2O2). In our design, phenylboronic ester-modified polymers were used as a modified cladding medium that allows chemo-optic transduction. Sensing is mechanistically based on oxidation and subsequent hydrolysis of the ph...

Improving sensitivity is critical for the higher-order harmonic fiber Bragg grating sensors. To this aim, in this work, we have successfully introduced the phase-shift into the third harmonic fiber Bragg grating for tailoring a double-dip spectrum with a high finesse notch. The dual dips showed reversed responses for the intensity regarding the cha...

Photonics has spurred a myriad of diagnostic and therapeutic applications for defeating cancer owing to its superiority in spatiotemporal maneuverability and minimal harm. The limits of light penetration depth and elusiveness of photosensitizer utilization, however, impede the implementation of the photodiagnostic and ‐therapy for determining and a...

Detecting nitroreductase (NTR) activity in hypoxic cells and tissues in situ represents an important step toward accurate delineation of hypoxic disease loci. However, it remains challenging to develop fluorescent probes with the necessary attributes of selectivity, sensitivity, precise targeting and aqueous solubility. Herein, two kinds of fluores...

Immunosensor is a powerful tool in healthcare and clinic, food and drug industry, and environmental protection. Label-free fiber-optic immunosensors have shown a myriad of advantages, such as high sensitivity, anti-electromagnetic interference, and afield measurement via the fiber network. However, the fiber-optic based sensor may bear the temperat...

Near-visible fiber Bragg grating finds myriad of applications such as quantum sensing, biomedical detection, and portable fiber probe. However, handling the requirements of flexibility, efficiency, and repeatability simultaneously remains a challenge for the state-of-the-art near-visible grating inscription techniques. This work proposes a highly e...

We demonstrate a microfiber Bragg grating as the reflective refractometer with the function of self-photoheating. The rare earth-doped fiber provides not only the photosensitivity to the UV modulation but also the effective pump laser absorption and photoheating conversion. The rare earth-doped microfiber Bragg grating, which is cladding-removed by...

Fiber-optic biosensor has shown tremendous promise in probing cardiac biomarkers label-free and in-operando. However, temperature cross-sensitivity is ubiquitously found and impedes further advances of the fiber-optic biosensors, especially for the scenario of rapid test at-body. In this study, we exploit a new regime that harnesses the harmonic re...

We report on a short-cavity polarization beat-frequency distributed Bragg reflector (DBR) fiber laser that can operate in an unprecedentedly wide range of temperatures from ${-}{{200}}^\circ {\rm{C}}$ to 500°C. The beat-frequency signal inherited by the intrinsic fiber birefringence enables implementation of the laser as an eligible temperature or...

We propose a temperature-compensable cardiac biomarker immunosensor using a reflective microfiber Bragg grating. By elevating the reaction temperature to 37 O C (human body characteristics), the detection time could be greatly shortened, enabling the potential of the rapid and in-vivo diagnosis on acute myocardial infarction.

We propose a highly flexible and applicable configuration- “ v ertical-fluid-array i nduced o ptic microfiber l ong per i od grati n g” (VIOLIN) to further explore the characteristics of the liquids. The high RI sensitivity of VIOLIN enables it a conveniently reproducible chemical sensor towards thiol compounds. The proof-of-concept could be descri...

Operando and precisely probing aqueous pH is fundamentally demanded, both in chemical and biological areas. Conventional pH probes, subjected to the larger size, are probably unfit for application in some extreme scenarios, such as a trace amount of samples. In this paper, we have further developed the pH sensor that leverages the microfiber Bragg...

Optofluidic sensors, which tightly bridge photonics and micro/nanofluidics, are superior candidates in point-of-care testing. A fiber-based interferometric optofluidic (FIO) sensor can detect molecular biomarkers by fusing an optical microfiber and a microfluidic tube in parallel. Light from the microfiber side coupled to the microtube leads to lat...

Fiber optical refractometers have gained a substantial reputation in biological and chemical sensing domain regarding their label-free and remote-operation working mode. However, the practical breakthrough of the fiber optical bio/chemosensor is impeded by a lack of reconfigurability as well as the explicitness of the determination between bulk and...

Fiber-optic biosensors are of great interest to many bio/chemical sensing applications. In this study, we demonstrate a high-order-diffraction long period grating (HOD-LPG) for the detection of prostate specific antigen (PSA). A HOD-LPG with a period number of less than ten and an elongated grating pitch could realize a temperature-insensitive and...

We present here a detailed investigation into the sensitivity of the taper-based Mach-Zehnder interferometer as a function of external refractive index, with particular attention to the dispersion turning point (DTP) and possibilities for ultra-sensitive sensors. Our numerical simulation revealed that two DTPs exist with a decrease in the microfibe...

To overcome the temperature cross-sensitivity of the microfiber Bragg grating (m-FBG) refractometer, we propose a novel refractive-index-temperature dual-sensing paradigm involving the third harmonic Bragg resonance that presents distinctive sensing characteristics. Strong resonances are obtained in both 1060 nm and 1550 nm wavebands under the modu...

A high-speed refractive index sensing system based on the Fourier domain mode locked laser (FDML) and a microfiber Bragg grating (mFBG) is theoretically studied and experimentally demonstrated. Unlike traditional physical parameter sensing systems, which directly use the FDML as the wavelength scanning source and the optical sensor as the spectra s...

Phase-shifted Bragg gratings have been extensively implemented in superior in-fiber bandpass filters or wavelength selectors, although high-temperature operation remains a challenge. We propose a phase-shifted type-IIa fiber Bragg grating (PSBG-IIa), which can conduct a notch signal as narrow as 4.8 pm within the stopband. The notch’s spectrum and...

Surface-enhanced Raman scattering (SERS)-based molecular sensing has emerged as a powerful tool in a wide variety of fields ranging from environmental monitoring, biomedical diagnostics to security applications. As versatile SERS probes, fiber-optrodes (i.e., a SERS substrate integrated on optical fibers) can simultaneously guide excitation laser a...

In this study, a high-resolution optical fiber Fabry–Pérot (FP) interferometer displacement sensor with chirped spectral characteristics based on a tapered microfiber is theoretically discussed and experimentally implemented. Instead of inscribing two fiber Bragg gratings (FBGs) on the symmetric position of the microfiber, we continuously inscribed...

A dual-wavelength fiber laser is proposed by the use of Er/Yb co-doped active fiber and a pair of novel Bragg-grating reflectors. The Bragg grating presents strong reflections of both third and second harmonics in accordance with the gain of ytterbium and erbium ion, respectively, enabling the laser emitted at 1.06 μm and 1.55 μm wavebands simultan...

A compact Fabry-Perot (F-P) interferometer with chirped spectral characteristics based on microfiber Bragg grating is theoretically discussed and experimentally implemented. The interferometer has flat reflective and its bandwidth is 20 nm.

Multiwavelength fiber lasers have progressed rapidly in recent decades. In this paper, a DBR fiber laser for simultaneously lasing at 1060 and 1550 nm wavebands is proposed by use of a novel fiber Bragg grating and a short piece of Er/Yb co-doped active fiber. Following the principle of formation on secondary fiber Bragg grating, a type of passive...

Cardiovascular diseases are leading culprits of the mortality worldwide. A fiber Bragg grating based label-free immunosensor is demonstrated for diagnosing acute heart disease which can be featured by the level of cardiac biomarkers in patients’ blood. The detection limit of 6 pg/mL to the cardiac troponin I, a type of cardiac biomarker, is obtaine...

A compact and label-free optical fiber sensor based on a taper interferometer cascaded with a fiber Bragg grating (FBG) is proposed and experimentally demonstrated for detection of a breast cancer biomarker (HER2). The tapered fiber-optic interferometer is extremely sensitive to the ambient refractive index (RI). In addition, being insensitive to t...

Nucleic acid detection with label-free biosensors circumvents the need for costly fluorophore functionalization steps associated with conventional assays by utilizing optical fiber transducers. In spite of their technological prowess, however, these biosensors’ sensitivity is limited by the design/configuration of their transducers. Therefore, it i...

In recent years, polarization-maintaining (PM) microfibers have attracted much research attention mostly due to their ultra-high birefringence and large evanescent field effect. This article starts from introduction of the structures, fabrication methods, and mode characteristics of PM microfibers. Different previously-implemented PM microfiber sen...

Being one of the most proven fiber optic devices, the fiber Bragg grating has developed continually to extend its applications, particularly in extreme environments. Accompanying the growth of Type-IIa Bragg gratings in some active fibers, a new resonance appears at the shorter wavelength. This new type of grating was named “secondary Bragg grating...

The human epidermal growth factor receptor 2 (HER2) is a clinically significant molecular marker of breast cancer. Interrogation of a high-resolution and temperature- compensational HER2 antigen biosensor based on a microwave photonics filter (MPF) is proposed and experimentally demonstrated. A microfiber Bragg grating (mFBG) and a regular fiber Br...

Chirped fiber Bragg gratings can straightforwardly and efficiently be fabricated onto microfibers with a uniform phase mask. Due to the variation of the propagating constant, which depends on the fiber diameter, the broadband spectrum of the grating can be formed. Depending on the different responses to the ambient refractive index in different par...

In this Letter, a 1-μm-wavelength fiber laser is proposed through the use of the ytterbium-doped active fiber and the third harmonic Bragg reflectors. Benefiting from the ratio below 0.5 between the core diameter of the fiber and the Talbot length of the UV fringes, enabling the formation of the secondary-type-In grating, the reflector with reflect...

The phase-shift Bragg gratings inscribed into microfibers are proposed. Depending on the narrow notch in the reflection spectrum, the grating can detect outer refractive index change with higher accuracy.

We demonstrate biomolecular detection based on the interference of optical modes in a microfiber-capillary optofluidic sensor. The optofluidic sensor is fabricated by aligning a microfiber in lateral contact with the capillary to form a modal interferometer. A biomolecular binding event at the capillary interior induces spectral shift of the interf...