In this work, we present the synthesis and application of fluorescent rhodamine B hydrazide for the derivatization of simple oligosaccharides and complex glycans using a hydrazone formation chemistry approach. The labeling conditions and the experimental setup of CE/LIF were optimized by analyzing oligosaccharide standards. The CE/LIF separations were performed in polybrene-coated capillaries eliminating the need for the purification step after derivatization. The addition of methanol to the background electrolyte significantly increased the LIF detection sensitivity reaching the limits of detection in the attomole range. The resolution of carbohydrate samples was improved by using long (98 cm) capillaries and polymer additives (polybrene). The developed method was applied for CE/LIF and CE-MS analysis of N-linked glycans released from bovine ribonuclease B and the therapeutic monoclonal antibody of trastuzumab.

• Keywords
• Capillary electrophoresis, Fluorescence, Glycan, Labeling, Mass spectrometry, Rhodamine B hydrazide,
• MeSH
• Electrophoresis, Capillary * methods   MeSH
• Fluorescent Dyes * chemistry   MeSH
• Spectrometry, Fluorescence methods   MeSH
• Mass Spectrometry methods   MeSH
• Lasers MeSH
• Oligosaccharides * chemistry   analysis   MeSH
• Polysaccharides * analysis   chemistry   MeSH
• Rhodamines * chemistry   MeSH
• Cattle MeSH
• Trastuzumab chemistry   analysis   MeSH
• Animals MeSH
• Check Tag
• Cattle MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Fluorescent Dyes * MeSH
• Oligosaccharides * MeSH
• Polysaccharides * MeSH
• rhodamine B MeSH Browser
• Rhodamines * MeSH
• Trastuzumab MeSH

AIMS: To investigate the concordance between the corneal power determined by various approaches with two tomographers (MS-39® and Galilei G6®) and the clinical history method (CHM) in patients undergoing photorefractive surgery with excimer laser for myopic errors. MATERIAL AND METHODS: Prospective cohort study. Patients undergoing keratorefractive surgery, and having pre- and postoperative keratometries, and tomographies, were included. RESULTS: In 90 eyes, the differences in the power estimated by the CHM and the one determined by four approaches with the corneal tomographers, which included measurements of the posterior cornea, did not show statistically significant differences in their averages. However, the 95% limits of agreement were very wide. After obtaining regression formulas to adjust the values of these four variables, the results of the agreement analysis were similar. CONCLUSION: Although certain values either directly determined or derived from measurements with the Galilei® and MS-39®corneal tomographers, approximated the estimated value of postoperative corneal power according to the CHM, due to the amplitude of their limits of agreement, these calculations must be taken with care, because they may not be accurate in a given eye.

• Keywords
• corneal power, corneal tomography, clinical history method, refractive surgery,
• MeSH
• Adult MeSH
• Photorefractive Keratectomy MeSH
• Lasers, Excimer therapeutic use   MeSH
• Humans MeSH
• Young Adult MeSH
• Myopia * surgery   physiopathology   diagnostic imaging   MeSH
• Prospective Studies MeSH
• Refraction, Ocular MeSH
• Cornea * diagnostic imaging   surgery   pathology   physiopathology   MeSH
• Corneal Topography MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

The high-sensitivity capabilities of laser-induced fluorescence (LIF) detection continuously promote the development of various labels with different fluorescence properties. However, this strategy also requires the adaptation of existing detection systems to suit the excitation and emission characteristics of novel fluorescent tags. In this study, we adapted the LIF detector of the commercial capillary electrophoresis instrument to the specific fluorescence spectra of 2-aminoacridone labeled human milk oligosaccharides. An external solid-state laser with a wavelength of 405 nm was connected to the commercial capillary electrophoresis instrument via a simple 3D-printed laser-to-light-guide adapter, and different optical filter setups were compared based on the signal-to-noise ratio. The optimized setup provided detection limits as low as 0.27 to 0.34 nM, corresponding to injection of 3.4 to 4.6 attomoles of 2-aminoacridone labeled oligosaccharides. These findings show that the optimized laser and filter configuration can enhance the sensitivity of electrophoretic separation by several orders of magnitude. In addition, the presented setup can be utilized as a guide for coupling different lasers to the commercial instrument.

• Keywords
• 2‐aminoacridone, capillary electrophoresis, human milk oligosaccharides, laser‐induced fluorescence,
• MeSH
• Aminoacridines * chemistry   MeSH
• Electrophoresis, Capillary * MeSH
• Fluorescence MeSH
• Fluorescent Dyes chemistry   MeSH
• Spectrometry, Fluorescence MeSH
• Lasers * MeSH
• Humans MeSH
• Milk, Human chemistry   MeSH
• Oligosaccharides * analysis   chemistry   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• 2-aminoacridone MeSH Browser
• Aminoacridines * MeSH
• Fluorescent Dyes MeSH
• Oligosaccharides * MeSH

Minimally invasive surgical techniques, including endoscopic and robotic procedures, continue to revolutionize patient care, for their ability to minimize surgical trauma, thus promoting faster recovery and reduced hospital stays. Yet, the suturing of soft tissues ensuring damage-free tissue bonding during these procedures remains challenging due to missing haptics and the fulcrum effect. Laser tissue soldering has potential in overcoming these issues, offering atraumatic seamless tissue fusion. To ensure the precision and safety of laser tissue soldering, the study introduces feedback-controlled fluorescent nanothermometry-guided laser tissue soldering using nanoparticle-protein solders within endoscopic and robotic contexts. Temperature-sensitive fluorescent nanoparticles embedded in the solder provide surgeons with immediate feedback on tissue temperatures during laser application, all while within the confines of minimally invasive (robotic) surgical setups. By integrating fluorescent nanothermometry-guided laser tissue surgery into endoscopic and robotic surgery, the study paves the way for a new approach for safe and atraumatic soft tissue joining, especially in regions where traditional suturing is unfeasible.

• Keywords
• feedback control, laparoscopy, minimally invasive surgery, nanomaterials, suturing,
• MeSH
• Lasers MeSH
• Humans MeSH
• Minimally Invasive Surgical Procedures * methods   MeSH
• Nanoparticles MeSH
• Robotic Surgical Procedures * methods   MeSH
• Thermometry * methods   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

BACKGROUND: Successful implementation of capillary isoelectric focusing (cIEF) in general requires the use of reference points - markers of isoelectric point. The low-molecular-mass fluorescent compounds based on the fluorescein structure, capable of marking distinct isoelectric points (pIs) with good focusing ability, stability, high extinction coefficient, and fluorescence are an alternative to the peptide and protein pI markers. RESULTS: Four synthetic pathways were used to produce the ampholytic compounds and the structures along with their basic physical and chemical properties are given. Previously published low-molecular-mass pI markers were used to calibrate the candidate fluorescent compounds using capillary IEF (cIEF) with laser-induced fluorescence (LIF) detection. Linear and point-to-point pI calibration approach were compared for the pI evaluation. The results show 21 fluorescent pI markers (FPIMs). This group of markers covers pH range from 3.10 to 10.21. The usability of the developed FPIMs was further demonstrated by analysis of fluorescein isothiocyanate (FITC) labeled immunoglobin (IgG) standard. SIGNIFICANCE AND NOVELTY: pI markers are crucial for tracking the pH gradient and pI determination of biological ampholytic compounds. This paper presents and characterizes a novel pI marker set capable of tracing isoelectric points and supporting highly sensitive LIF detection-based applications. A basis of a newly developed cIEF-based fractionation method is described as well.

• Keywords
• Capillary isoelectric focusing, Isoelectric point marker, Laser-induced fluorescence, Protein characterization,
• MeSH
• Electrophoresis, Capillary methods   MeSH
• Fluorescein * chemistry   MeSH
• Fluorescence MeSH
• Fluorescent Dyes chemistry   MeSH
• Spectrometry, Fluorescence MeSH
• Isoelectric Focusing * methods   MeSH
• Isoelectric Point MeSH
• Capillary Isoelectric Focusing MeSH
• Hydrogen-Ion Concentration MeSH
• Lasers * MeSH
• Molecular Weight MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Fluorescein * MeSH
• Fluorescent Dyes MeSH

Correlative imaging of cutaneous tumors provides additional information to the standard histopathologic examination. However, the joint progress in the establishment of analytical techniques, such as Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) in clinical practice is still limited. Their combination provides complementary information as it is also shown in our study in terms of major biotic (Ca, Mg, and P) and trace (Cu and Zn) elements. To elucidate changes in the elemental composition in tumors, we have compiled a set of malignant tumors (Squamous Cell Carcinoma, Basal Cell Carcinoma, Malignant Melanoma, and Epithelioid Angiosarcoma), one benign tumor (Pigmented Nevus) and one healthy-skin sample. The data processing was based on a methodological pipeline involving binary image registration and affine transformation. Thus, our paper brings a feasibility study of a practical methodological concept that enables us to compare LIBS and LA-ICP-MS results despite the mutual spatial distortion of original elemental images. Moreover, we also show that LIBS could be a sufficient pre-screening method even for a larger number of samples according to the speed and reproducibility of the analyses. Whereas LA-ICP-MS could serve as a ground truth and reference technique for preselected samples.

• Keywords
• Digital histopathology, LA-ICP-MS, LIBS, Numerical correlations, Skin tumor,
• MeSH
• Carcinoma, Basal Cell diagnostic imaging   MeSH
• Mass Spectrometry methods   MeSH
• Laser Therapy MeSH
• Lasers MeSH
• Humans MeSH
• Melanoma diagnostic imaging   pathology   MeSH
• Skin Neoplasms * diagnostic imaging   pathology   MeSH
• Nevus, Pigmented diagnostic imaging   MeSH
• Spectrum Analysis methods   MeSH
• Carcinoma, Squamous Cell diagnostic imaging   pathology   MeSH
• Trace Elements analysis   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Trace Elements MeSH

Laser-induced breakdown spectroscopy (LIBS) is a promising technique for the readout of immunochemical assays utilizing indirect detection of labels (Tag-LIBS), typically based on nanoparticles. We have previously demonstrated that Tag-LIBS immunoassay employing yttrium-based photon-upconversion nanoparticles (UCNPs) can reach sensitivity similar to commonly used enzyme and fluorescence immunoassays. In this study, we report on further increasing the sensitivity of UCNP-based Tag-LIBS immunoassay by employing magnetic microbeads (MBs) as the solid phase in the determination of cancer biomarker prostate-specific antigen. Due to the possibility of analyte preconcentration, MBs enabled achieving a limit of detection (LOD) of 4.0 pg·mL-1, representing two orders of magnitude improvement compared with equivalent microtiter plate-based assay (LOD of 460 pg·mL-1). In addition, utilizing MBs opens up the possibility of an internal standardization of the LIBS readout by employing iron spectral lines, which improves the assay robustness by compensating for LIBS signal fluctuations and bead-bound immunocomplexes lost throughout the washing steps. Finally, the practical applicability of the technique was confirmed by the successful analysis of clinical samples, showing a strong correlation with the standard electrochemiluminescence immunoassay. Overall, MB-based Tag-LIBS was confirmed as a promising immunoassay approach, combining fast readout, multiplexing possibilities, and high sensitivity approaching upconversion luminescence scanning while avoiding the requirement of luminescence properties of labels.

• Keywords
• Double-pulse LIBS, Magnetic microparticle, Photon-upconversion nanoparticle, Prostate-specific antigen, Tag-LIBS,
• MeSH
• Immunoassay methods   MeSH
• Lasers * MeSH
• Humans MeSH
• Limit of Detection * MeSH
• Microspheres MeSH
• Prostate-Specific Antigen * analysis   immunology   blood   MeSH
• Spectrum Analysis methods   MeSH
• Yttrium chemistry   radiation effects   MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Prostate-Specific Antigen * MeSH
• Yttrium MeSH

Contamination of the environment with toxic metals such as cadmium or lead is a worldwide issue. The accumulator of metals Cannabis sativa L. has potential to be utilized in phytoremediation, which is an environmentally friendly way of soil decontamination. Novel non-thermal plasma-based technologies may be a helpful tool in this process. Plasma activated water (PAW), prepared by contact of gaseous plasma with water, contains reactive oxygen and nitrogen species, which enhance the growth of plants. In this study, C. sativa was grown in a short-term toxicity test in a medium which consisted of plasma activated water prepared by dielectric barrier discharge with liquid electrode and different concentrations of cadmium or lead. Application of PAW on heavy metal contaminated C. sativa resulted in increased growth under Pb contamination as was determined by ecotoxicology tests. Furthermore, the PAW influence on the bioaccumulation of these metals as well as the influence on the nutrient composition of plants was studied primarily by applying Laser-induced breakdown spectroscopy (LIBS). The LIBS elemental maps show that C. sativa accumulates heavy metals mainly in the roots. The results present a new proof-of-concept in which PAW could be used to improve the growth of plants in heavy metal contaminated environment, while LIBS can be implemented to study the phytoremediation efficiency.

• Keywords
• Cadmium, Contamination, Lead, Non-thermal plasma, Phytoremediation, Toxic metals,
• MeSH
• Bioaccumulation * MeSH
• Biodegradation, Environmental * MeSH
• Cannabis * metabolism   MeSH
• Cadmium * toxicity   metabolism   MeSH
• Plant Roots metabolism   MeSH
• Lasers * MeSH
• Soil Pollutants * toxicity   metabolism   MeSH
• Lead * metabolism   toxicity   MeSH
• Plasma Gases MeSH
• Spectrum Analysis methods   MeSH
• Metals, Heavy * MeSH
• Water chemistry   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Cadmium * MeSH
• Soil Pollutants * MeSH
• Lead * MeSH
• Plasma Gases MeSH
• Metals, Heavy * MeSH
• Water MeSH

The diagnosis of malignant melanoma, often an inconspicuous but highly aggressive tumor, is most commonly done by histological examination, while additional diagnostic methods on the level of elements and molecules are constantly being developed. Several studies confirmed differences in the chemical composition of healthy and tumor tissue. Our study presents the potential of the LIBS (Laser-Induced-Breakdown Spectroscopy) technique as a diagnostic tool in malignant melanoma (MM) based on the quantitative changes in elemental composition in cancerous tissue. Our patient group included 17 samples of various types of malignant melanoma and one sample of healthy skin tissue as a control. To achieve a clear perception of results, we have selected two biogenic elements (calcium and magnesium), which showed a dissimilar distribution in cancerous tissue from its healthy surroundings. Moreover, we observed indications of different concentrations of these elements in different subtypes of malignant melanoma, a hypothesis that requires confirmation in a more extensive sample set. The information provided by the LIBS Imaging method could potentially be helpful not only in the diagnostics of tumor tissue but also be beneficial in broadening the knowledge about the tumor itself.

• Keywords
• Chemical analysis, Cutaneous cancer, Diagnostics, Digital histopathology, Optical emission spectroscopy, Skin tumor,
• MeSH
• Magnesium * analysis   MeSH
• Lasers * MeSH
• Humans MeSH
• Melanoma * pathology   diagnostic imaging   diagnosis   chemistry   MeSH
• Skin Neoplasms * pathology   diagnostic imaging   MeSH
• Spectrum Analysis * methods   MeSH
• Calcium analysis   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Magnesium * MeSH
• Calcium MeSH

BACKGROUND: Laser-induced breakdown spectroscopy (LIBS) is a well-recognized analytical technique used for elemental analysis. This method is gaining considerable attention also in biological applications thanks to its ability for spatial mapping and elemental imaging. The implementation of LIBS in the biomedical field is based on the detection of metals or other elements that either naturally occur in the samples or are present artificially. The artificial implementation of nanoparticle labels (Tag-LIBS) enables the use of LIBS as a readout technique for immunochemical assays. However, one of the biggest challenges for LIBS to meet immunoassay readout standards is its sensitivity. RESULTS: This paper focuses on the improvement of LIBS sensitivity for the readout of nanoparticle-based immunoassays. First, the LIBS setup was optimized on photon-upconversion nanoparticle (UCNP) droplets deposited on the microtiter plate wells. Two collection optics systems were compared, with single pulse (SP) and collinear double pulse (DP) LIBS arrangements. By deploying the second laser pulse, the sensitivity was improved up to 30 times. The optimized SP and DP setups were then employed for the indirect detection of human serum albumin based on immunoassay with UCNP-based labels. Compared to our previous LIBS study, the detection limit was enhanced by two orders of magnitude, from 10 ng mL-1 to 0.29 ng mL-1. In addition, two other immunochemical methods were used for reference, based on the readout of upconversion luminescence of UCNPs and absorbance measurement with enzyme labels. Finally, the selectivity of the assay was tested and the practical potential of Tag-LIBS was demonstrated by the successful analysis of urine samples. SIGNIFICANCE AND NOVELTY: In this work, we improved the sensitivity of the Tag-LIBS method by combining new labels based on UCNPs with the improved collection optics and collinear DP configuration. In the instrumental setup optimization, the DP LIBS showed better sensitivity and signal-to-noise ratio than SP. The optimizations allowed the LIBS readout to surpass the sensitivity of enzyme immunoassay, approaching the qualities of upconversion luminescence readout, which is nowadays a state-of-the-art readout technique.

• Keywords
• Double pulse, Human serum albumin, Immunoassay, Laser-induced breakdown spectroscopy, Photon-upconversion nanoparticle, Tag-LIBS,
• MeSH
• Immunoassay methods   MeSH
• Metals MeSH
• Lasers MeSH
• Humans MeSH
• Nanoparticles * chemistry   MeSH
• Spectrum Analysis methods   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Metals MeSH