OBJECTIVES: To establish a rapid and nondestructive identification method for human body fluid stains and non-biological stains using three-dimensional fluorescence spectroscopy. METHODS: The collected three-dimensional fluorescence spectrum data of human saliva, 3% blood, coffee and Fanta^® stains were processed with dimensionality reduction. After wavelet transform, spectral denoising and feature extraction, the classification formula was established. The Fisher discriminant was used for spectrum matching and recognition to establish the analysis method to distinguish stain types. RESULTS: According to the results of data training and comparison, all the recognition accuracies of Fanta^®, coffee, saliva and blood were more than 91.39%. Among them, saliva reached 100% recognition accuracy. CONCLUSIONS Three-dimensional fluorescence spectroscopy is a potential method for rapid and nondestructive identification of biological and non-biological stains.
Humans ; Forensic Medicine/methods* ; Coloring Agents/analysis* ; Coffee ; Spectrometry, Fluorescence ; Body Fluids/chemistry*

The current quantitative methods of bilirubin have disadvantages such as high cost and low sensitivity. Due to the negative correlation between the level of serum bilirubin and the risk of cardiovascular diseases, a fluorescent ratiometric film sensor was developed aiming at bilirubin detection at low level concentration. Blue-emitting and red-emitting gold nanoclusters were assembled into the same film using layer-by-layer self-assembly technology. Detection of bilirubin was achieved based on the intensity ratio of the two nanoclusters. Bilirubin exposure causes fluorescent quenching of the film. The fluorescence intensity ratio of the two cluster probes had quantitative relationship versus bilirubin concentration. Based on this film sensor, a portable fluorescence detection system was designed for the ratiometric sensing of bilirubin. The hardware of the system was mainly composed of main control chip STM32F407, TSL237 and TSL238T optical frequency sensor. A light-avoiding dark room and detection light path were designed through three-dimensional printing to reduce the interference from ambient light and improve detection accuracy. Experimental results showed that the proposed detection system had strong anti-interference, good stability and accuracy. The linear coefficient of bilirubin detected by this system was 0.987. The system presented good results in reproducible experiments and possessed a good linear relationship with the data obtained by standard spectrofluorometer. The portable system is expected to detect serum bilirubin at low levels.
Bilirubin ; Fluorescence ; Fluorescent Dyes ; Gold ; Metal Nanoparticles ; Spectrometry, Fluorescence/methods*

Microarc oxidation (MAO) has become a promising technique for the surface modification of implants. Therefore, the aims of this study were to further quantitatively and qualitatively evaluate the osteointegration abilities of MAO-treated and smooth surface (SF) implants in vivo and to investigate the areas in which the superiority of MAO-treated implants are displayed. In a rabbit model, a comprehensive histomorphological, osteogenic, mineralizational, and integrative assessment was performed using light microscopy, fluorescence microscopy, confocal laser scanning microscopy, and radiographic analyses. Compared with the SF groups, the MAO-treated groups exhibited more active contact osteogenesis, as well as distant osteogenesis, under fluorescence examination, the mineral apposition rate was found to be greater for all of the MAO-treated implants, and the osteointegration index (OI) value was greater in the MAO-treated groups at different times. In conclusion, the calcium-rich amorphous layer created by MAO provided a better environment for osteointegration, with more active contact osteogenesis, a more rapid mineral apposition rate and greater OI values.
Animals ; Bone-Implant Interface ; physiology ; Dental Implantation, Endosseous ; methods ; Dental Implants ; Femur ; surgery ; Implants, Experimental ; Materials Testing ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Microscopy, Fluorescence ; Models, Animal ; Osseointegration ; physiology ; Oxidation-Reduction ; Rabbits ; Spectrometry, X-Ray Emission ; Surface Properties ; Titanium

Antimony ; urine ; Flow Injection Analysis ; Spectrometry, Fluorescence ; methods ; Spectrophotometry, Atomic ; methods

Optical spectroscopy devices are being developed and tested for the screening and diagnosis of oral precancer and cancer lesions. This study reports a device that uses white light for detection of suspicious lesions and green-amber light at 545 nm that detect tissue vascularity on patients with several suspicious oral lesions. The clinical grading of vascularity was compared to the histological grading of the biopsied lesions using specific biomarkers. Such a device, in the hands of dentists and other health professionals, could greatly increase the number of oral cancerous lesions detected in early phase. The purpose of this study is to correlate the clinical grading of tissue vascularity in several oral suspicious lesions using the Identafi(®) system with the histological grading of the biopsied lesions using specific vascular markers. Twenty-one patients with various oral lesions were enrolled in the study. The lesions were visualized using Identafi(®) device with white light illumination, followed by visualization of tissue autofluorescence and tissue reflectance. Tissue biopsied was obtained from the all lesions and both histopathological and immunohistochemical studies using a vascular endothelial biomarker (CD34) were performed on these tissue samples. The clinical vascular grading using the green-amber light at 545 nm and the expression pattern and intensity of staining for CD34 in the different biopsies varied depending on lesions, grading ranged from 1 to 3. The increase in vascularity was observed in abnormal tissues when compared to normal mucosa, but this increase was not limited to carcinoma only as hyperkeratosis and other oral diseases, such as lichen planus, also showed increase in vascularity. Optical spectroscopy is a promising technology for the detection of oral mucosal abnormalities; however, further investigations with a larger population group is required to evaluate the usefulness of these devices in differentiating benign lesions from potentially malignant lesions.
Adult ; Aged ; Aged, 80 and over ; Antigens, CD34 ; analysis ; Biomarkers, Tumor ; analysis ; Biopsy ; methods ; Carcinoma, Squamous Cell ; blood supply ; diagnosis ; pathology ; Erythroplasia ; diagnosis ; pathology ; Female ; Humans ; Immunohistochemistry ; Leukoplakia, Oral ; blood supply ; diagnosis ; pathology ; Lichen Planus, Oral ; diagnosis ; pathology ; Male ; Middle Aged ; Mouth Neoplasms ; blood supply ; diagnosis ; pathology ; Neoplasm Grading ; Optical Imaging ; methods ; Pilot Projects ; Precancerous Conditions ; blood supply ; diagnosis ; pathology ; Spectrometry, Fluorescence ; methods ; Young Adult

OBJECTIVETo establish a derivative fluorometry method for the determination of sulfur dioxide residues in traditional Chinese medicine.

METHODThe optimal derivation condition was established. The fluorescence intensity was detected at excitation wavelength of 321 nm, and emission wavelength of 384 nm.

RESULTA linear relationship was obtained between the fluorescence intensity and the addition of reference substance in the range of 0.999 7-17.99 nmol with a correlation coeffient of 0.999 9, and the average recovery was 102.3% with RSD 4.6%.

CONCLUSIONThis method is simple and sensitive with quick and correct result. It can provide a reference for the determination of sulfur dioxide residues in traditional Chinese medicine.

Drugs, Chinese Herbal ; analysis ; Fluorescence ; Medicine, Chinese Traditional ; Sensitivity and Specificity ; Species Specificity ; Spectrometry, Fluorescence ; methods ; Sulfur Dioxide ; analysis ; Temperature

Botryococcus braunii is a unique colonial green microalga and a great potential renewable resource of liquid fuel because of its ability to produce lipids. Due to the dense cell colonies and rigidly thick cell wall of B. braunii, the traditional Nile red method is usually of low sensitivity and bad repeatability and hard for the determination of lipid content in the cells. By dispersing the colony with ultrasonic, assisting permeation of Nile red across the cell wall with dimethyl sulfoxide and optimizing the staining conditions, we established an improved detection method. The details were as follows: after the colonial algal sample was treated by ultrasonic at 20 kHz for 20 s, 100 W transmitting power and with 1 s on/1 s off intermittent cycle, the equivoluminal 15% (V/V) dimethyl sulfoxide and 3 microg/mL Nile red were successively added and mixed evenly, then the staining system was incubated in dark at 40 degrees C for 10 min, and subsequently was measured by fluorescence spectroscopy detection with an excitation wavelength of 490 nm. Compared with the traditional method, the improved one not only had higher detection sensitivity which was increased by 196.6%, but also had obviously better detection repeatability whose characteristic parameter - relative standard deviation (RSD) was decreased from 10.91% to 1.84%. Therefore, the improved method could provide a rapid and sensitive detection of lipid content for B. braunii breeding and cultivation.
Chlorophyta ; chemistry ; Lipids ; analysis ; Microalgae ; chemistry ; Spectrometry, Fluorescence ; methods ; Ultrasonics

To meet the needs of detection of infectious bursal disease virus (IBDV) under high efficient culture, a SYBR Green I real-time RT-PCR (qRT-PCR) was developed using a pair of primers specific to the conserved region of VP4 gene of IBDV and compared with TCID50 method by monitoring the proliferation dynamics of IBDV in DF-1 cell line adherent to micro carrier in tubular reactor. The results showed that the RT-PCRassay was linear in the range of 4. 03 X 10(1)-10(9) copies/microL. The IBDV RNA detection limit was 40 copies/microL, which was 1 000 times more sensitive than conventional PCR. No cross-reactions with other viruses was observed. The intra-assay coefficient of variation was less than 0.05%. There was a parallel correlation of IBDV proliferation dynamics in DF-1 cell under Micro carrier suspension and static adherent culture by the qRT-PCR assay and TCID50 method. The detection results of the IBDV samples from tubular and flask culture showed the differences of the micro carrier and adherent culture by both methods. In conclusion, the qRT-PCR assay is more rapid and sensitive than the TCID50 method, which is more appropriate for the real time detection of IBDV.
Animals ; Calibration ; Cell Line ; Conserved Sequence ; DNA Primers ; genetics ; Infectious bursal disease virus ; genetics ; isolation & purification ; Organic Chemicals ; chemistry ; metabolism ; Real-Time Polymerase Chain Reaction ; methods ; Reproducibility of Results ; Spectrometry, Fluorescence ; Viral Proteins ; genetics ; Virus Replication

The real-time in vivo measurement method has been urgently needed in the research of pharmacokinetics. In the present paper a new in vivo detection method based on fluorescence spectroscopy has been proposed and the monitoring system has been built which is used for pharmacokinetics studies in rats. The relationship between fluorescence intensity and concentration was obtained. By detecting the fluorescent dye Cypate in real-time in rats, the properties of the system have been validated by comparing with the fluorescence imaging system in vitro. The results showed that the system could be feasible for: (1) The linear regression equation of Cypate concentration in the range of 0.098-25 microg/ml is y = 73.249x + 130.97 (R2 = 0.9991 and P < 0.001). RSD of high, medium and low concentration is 1.23%, 6.29% and 13.48%, respectively, and the detecting sensitivity is 0.0981 g/ml; (2) The fluorescent dye concentration from the system is consistent (r = 0.9925) with the fluorescence imaging system in vitro. The fluorescent dye metabolism in rats can be well detected. It can be concluded that a new real-time in vivo detecting method in the paper can be used in pharmacokinetics research.
Animals ; Fluorescent Dyes ; pharmacokinetics ; Rats ; Spectrometry, Fluorescence ; methods ; Spectroscopy, Near-Infrared ; methods

OBJECTIVETo characterize the relationship between the refolding process of recombinant bovine β-lactoglobulin and its immunoreactivity for clinical purposes. To establish a spectral method which examine the extent of recombinant allergen renaturation.

METHODSThe refolding process of recombinant bovine β-lactoglobulin was investigated by using circular dichroism, fluorescence and synchronous fluorescence spectra. IgE-binding capacity of recombinant protein was analyzed by ELISA. In addition, bioinformatic methods were used to explain the spectral characteristics and analyze the relationship between the conformational changes and the immunoreactivity of the protein during renaturation in vitro.

RESULTSRenaturation of recombinant bovine β-lactoglobulin resulted in a more compact structure resembling the natural counterpart with stronger IgE-binding capacity.

CONCLUSIONThe degree of protein renaturation correlated with the IgE-binding capacity of the protein. Results from this study may be of help for food allergy therapy and development of vaccination in the future.

Allergens ; Animals ; Cattle ; Circular Dichroism ; Enzyme-Linked Immunosorbent Assay ; Immunoglobulin E ; Lactoglobulins ; chemistry ; metabolism ; Models, Molecular ; Protein Binding ; Protein Conformation ; Protein Denaturation ; Protein Folding ; Spectrometry, Fluorescence ; methods