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The accurate determination of protein structure is integral to the medical and pharmaceutical communities’ ability to understand disease, and develop drugs. Current techniques (CD, IR, Raman) for protein structure prediction provide results that can be poorly resolved, while high resolution techniques (NMR, X-ray crystallography) can be both costly and time-consuming. This work proposes the use of drop coat deposition confocal Raman spectroscopy (DCDCR), coupled with peak fitting of the Amide I spectral region (1620–1720 cm-1) for the accurate determination of protein secondary structure. Studies conducted on BSA and ovalbumin show that the predictions of secondary structure content within 1% of representative crystal structure data is possible for model proteins. The results clearly demonstrate that DCDCR has the potential to be effectively used to obtain accurate secondary structure distributions for proteins.

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The accurate determination of protein structure is integral to the medical and pharmaceutical communities’ ability to understand disease, and develop drugs. Current techniques (CD, IR, Raman) for protein structure prediction provide results that can be poorly resolved, while high resolution techniques (NMR, X-ray crystallography) can be both costly and time-consuming. This work proposes the use of drop coat deposition confocal Raman spectroscopy (DCDCR), coupled with peak fitting of the Amide I spectral region (1620–1720 cm-1) for the accurate determination of protein secondary structure. Studies conducted on BSA and ovalbumin show that the predictions of secondary structure content within 1% of representative crystal structure data is possible for model proteins. The results clearly demonstrate that DCDCR has the potential to be effectively used to obtain accurate secondary structure distributions for proteins.

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The accurate determination of protein structure is integral to the medical and pharmaceutical communities’ ability to understand disease, and develop drugs. Current techniques (CD, IR, Raman) for protein structure prediction provide results that can be poorly resolved, while high resolution techniques (NMR, X-ray crystallography) can be both costly and time-consuming. This work proposes the use of drop coat deposition confocal Raman spectroscopy (DCDCR), coupled with peak fitting of the Amide I spectral region (1620–1720 cm-1) for the accurate determination of protein secondary structure. Studies conducted on BSA and ovalbumin show that the predictions of secondary structure content within 1% of representative crystal structure data is possible for model proteins. The results clearly demonstrate that DCDCR has the potential to be effectively used to obtain accurate secondary structure distributions for proteins.

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Surface plasmon resonance, charge-transfer resonance, and their combination determine the enhancement of surface-enhanced Raman scattering signals, and the varying intensities of the signal at different pH levels may result from the change in contributions of the combined system.

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UVISEL ellipsometers have been used for the characterization of several systems of nanoparticles. This ellipsometric characterization involves the development of specific modeling tools available within DeltaPsi2 software.

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Milestone’s UltraWAVE SRC benchtop microwave digestion enables cosmetic chemists to digest up to 15 different sample types simultaneously at temperatures as high as 300°C, greatly simplifying product development workflow with an easy efficient digestion sequence.

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Strict and steady food control protects consumers against undesired contaminations and guarantees a high level of quality. This can be achieved by enforcing maximum allowable concentrations of hazardous substances. For simultaneous quantitative determination of the inorganic elements in wine, the ICP-MS technique is the preferred quality control tool. ICP-MS offers high sensitivity (trace detection), a wide dynamic range and a high sample throughput. In this study, commercially available red and white wines were investigated; 14 different elements were quantified simultaneously: arsenic, cadmium, caesium, copper, chromium, vanadium, iron, manganese, nickel, lead, selenium, tin, thallium and zinc. The developed ICP-MS method has a high accuracy, regardless of element concentration.

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Teledyne Leeman Labs QuickTrace® M7600 was used to analyze and determine total elemental mercury (Hg0) concentration in Tuna (CRM 463) following the guidance in USDA Method CLG-MERC1.01 and the operating conditions.

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Photoluminescence and electroluminescence spectroscopy is a useful technique in the investigation of organic optoelectronic devices. The instrumentation for steady-state and time-resolved photoluminescence, as well as electroluminescence, is specified in this application note on organic solar cells.

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A summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS

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October’s AP column highlights a team of geochemists at the University of Houston who have been developing methods to streamline multi-element analysis for a more complete fingerprinting of oils by using one sample preparation method utilizing a single reaction chamber microwave digestion system and then analyzing these solutions for major, and minor elements by ICP-OES and low abundance trace elements by triple quadrupole (QQQ) ICP-MS. Results to date using this approach have shown that complete elemental recovery and removal of organic matrices can be achieved safely and that up to 57 elements can be determined in oils with good accuracy and precision. Removal of organic matrices during digestion not only helps to limit the formation of polyatomic spectral interferences, but improves instrument stability and reduces carbon build in the sample introduction and interface regions, which have traditionally plagued “dilute and shoot” methods.

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A breakthrough using a microfluidic interface to conduct sensitive time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis and study liquid surfaces in situ under vacuum conditions is described here.

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A critical review focused on the Raman spectroscopy of carbonaceous materials and of polymer-based nanocomposites that contain carbonaceous (nano) materials as fillers

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A fluoride-regeneration approach enables biomonitoring of chemical warfare nerve agents.

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When characterizing microscale objects using a Raman microscope, certain basic practical aspects of analytical instrument performance and experimental design should be taken into consideration.

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Raman spectroscopy is a rapidly expanding field, with modern Raman spectrometers offering labs higher ease of use and sensitivity. Furthermore, combining Raman spectroscopy with scanning electron microscopy (SEM) and fluorescence-lifetime imaging microscopy (FLIM) can enhance the technique for various applications.

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Strict and steady food control protects consumers against undesired contaminations and guarantees a high level of quality. This can be achieved by enforcing maximum allowable concentrations of hazardous substances. For simultaneous quantitative determination of the inorganic elements in wine, the ICP-MS technique is the preferred quality control tool. ICP-MS offers high sensitivity (trace detection), a wide dynamic range and a high sample throughput. In this study, commercially available red and white wines were investigated; 14 different elements were quantified simultaneously: arsenic, cadmium, caesium, copper, chromium, vanadium, iron, manganese, nickel, lead, selenium, tin, thallium and zinc. The developed ICP-MS method has a high accuracy, regardless of element concentration.

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In this study, recovery rates between 92% and 105%, combined with very low variations (RSD

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Strict and steady food control protects consumers against undesired contaminations and guarantees a high level of quality. This can be achieved by enforcing maximum allowable concentrations of hazardous substances. For simultaneous quantitative determination of the inorganic elements in wine, the ICP-MS technique is the preferred quality control tool. ICP-MS offers high sensitivity (trace detection), a wide dynamic range and a high sample throughput. In this study, commercially available red and white wines were investigated; 14 different elements were quantified simultaneously: arsenic, cadmium, caesium, copper, chromium, vanadium, iron, manganese, nickel, lead, selenium, tin, thallium and zinc. The developed ICP-MS method has a high accuracy, regardless of element concentration.

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Despite all of the recent advances in analytical technologies dedicated to biotherapeutics, accurate protein quantification remains a challenge for the biopharmaceutical industry. UV spectrophotometry is commonly used for batch testing, but it requires the knowledge of the extinction coefficient of the protein, whose experimental determination requires the accurate concentration of a reference standard obtained by an absolute quantification method. To address the need for a fast analytical method capable of accurately quantifying a protein without any specific reference substance, an isotope dilution ICP-MS method was developed and validated, based on sulfur determination, allowing very accurate determination of a single protein in solution after microwave digestion.

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Despite all of the recent advances in analytical technologies dedicated to biotherapeutics, accurate protein quantification remains a challenge for the biopharmaceutical industry. UV spectrophotometry is commonly used for batch testing, but it requires the knowledge of the extinction coefficient of the protein, whose experimental determination requires the accurate concentration of a reference standard obtained by an absolute quantification method. To address the need for a fast analytical method capable of accurately quantifying a protein without any specific reference substance, an isotope dilution ICP-MS method was developed and validated, based on sulfur determination, allowing very accurate determination of a single protein in solution after microwave digestion.

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Chronic kidney disease or kidney complication resulting from another systematic disorder can impact the organ’s blood filtering capability resulting in the passage of blood-born proteins through the kidneys and into urine.  Clinical analyses for blood proteins in urine are performed to assess proper kidney function or to monitor a diagnosed disorder.  Serum albumin is a common target in these clinical assays and detection of elevated SA levels in urine is termed Albuminuria. Because of normal variability in urine content and volume multiple measurements are often made in comparison to creatitine levels within the same urine sample and reported as a ratio (ACR).  Demonstrated here is a novel means for quantifying albumin and creatinine directly from the same urine sample using MALDI-TOF mass spectrometry.  Standard addition of albumin and deuterated creatinine (d3) into control urine produced a linear and quantitative response (R2 = 0.99 and 0.98) and is used to quantify both analytes across their clinically relevant ranges. This MS-based method represents a simple, fast, attractive alternative to currently clinical methods.

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Chronic kidney disease or kidney complication resulting from another systematic disorder can impact the organ’s blood filtering capability resulting in the passage of blood-born proteins through the kidneys and into urine.  Clinical analyses for blood proteins in urine are performed to assess proper kidney function or to monitor a diagnosed disorder.  Serum albumin is a common target in these clinical assays and detection of elevated SA levels in urine is termed Albuminuria. Because of normal variability in urine content and volume multiple measurements are often made in comparison to creatitine levels within the same urine sample and reported as a ratio (ACR).  Demonstrated here is a novel means for quantifying albumin and creatinine directly from the same urine sample using MALDI-TOF mass spectrometry.  Standard addition of albumin and deuterated creatinine (d3) into control urine produced a linear and quantitative response (R2 = 0.99 and 0.98) and is used to quantify both analytes across their clinically relevant ranges. This MS-based method represents a simple, fast, attractive alternative to currently clinical methods.

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Chronic kidney disease or kidney complication resulting from another systematic disorder can impact the organ’s blood filtering capability resulting in the passage of blood-born proteins through the kidneys and into urine.  Clinical analyses for blood proteins in urine are performed to assess proper kidney function or to monitor a diagnosed disorder.  Serum albumin is a common target in these clinical assays and detection of elevated SA levels in urine is termed Albuminuria. Because of normal variability in urine content and volume multiple measurements are often made in comparison to creatitine levels within the same urine sample and reported as a ratio (ACR).  Demonstrated here is a novel means for quantifying albumin and creatinine directly from the same urine sample using MALDI-TOF mass spectrometry.  Standard addition of albumin and deuterated creatinine (d3) into control urine produced a linear and quantitative response (R2 = 0.99 and 0.98) and is used to quantify both analytes across their clinically relevant ranges. This MS-based method represents a simple, fast, attractive alternative to currently clinical methods.