Unprocessed Specimens Research Articles

Lipophilic and friction properties of 20CrMnTi steel with laser-induced texturing

Laser surface texturing is an effective method to enhance gear lubrication by improving lipophilic properties, thereby increasing transmission performance and longevity. This study investigated the effects of laser parameters on lipophilicity using a grid texture and found that a scanning speed of 100 mm/s maximized diffusion and climbing. The textured specimens showed higher wetting hysteresis and adsorption, forming a thicker oil film for better lubrication. Wear tests indicated that the textured specimen had reduced friction, wear quality, and depth by 49.2% and 66.34% compared to unprocessed specimens. Gear efficiency is effectively increased, and gear oil temperature is significantly reduced. This research offers insights into lipophilic characterization and gear lubrication enhancement, potentially decreasing surface failures like pitting, adhesion, and wear.

Enhanced lipophilicity and wear resistance of 20CrMnTi induced by laser surface texturing

Gear transmission is crucial in mechanical engineering, extensively used in automobiles, ships, machine tools, and airplanes. However, as gear systems advance towards higher speeds, heavier loads, and smaller sizes, the tooth surface becomes more prone to pitting, wear, and other failures. The use of laser surface texturing technology has shown great promise in enhancing the hydrophobic and lipophilic properties of material surfaces. Thus, this paper presents a novel approach for machining equally spaced parallel and perpendicular microgrooves on the surface of gear steels (20CrMnTi) to facilitate lubricant storage and enhance the material’s surface lipophilicity. Laser power and scanning speed are optimized as parameters for laser processing to investigate the lipophilic properties, including the contact angle, diffusion velocity, and contact behavior of oil droplets. Comparative analysis of the processed and unprocessed specimens revealed that both static and dynamic contact behaviors are significantly changed. Compared with the unprocessed specimens, the static contact angle of the processed specimens decreases from 47° to 0° and is super lipophilic at different temperatures; the oil droplet diffusion distance increases by a maximum of 1.27 times; the vertical diffusion height increases by a maximum of 2.8 mm; and the wetting hysteresis coefficient increases by a maximum of 2.55 times. Additionally, the friction coefficient decreases during the stable wear phase, and the wear depth is reduced by 33.53 %. The research has demonstrated that the oil-attracting properties of 20CrMnTi can be greatly enhanced using laser micro-nano texture technology. This improves lubrication conditions and wear resistance, providing a novel approach to mitigating failure risks such as pitting and wear in various gear mechanisms. Furthermore, this method effectively extends the service life of gears, making it a valuable tool for gear engineering applications.

Ultraviolet metasurface-assisted photoacoustic microscopy with great enhancement in DOF for fast histology imaging

Pathology interpretations of tissue rely on the gold standard of histology imaging, potentially hampering timely access to critical information for diagnosis and management of neoplasms because of tedious sample preparations. Slide-free capture of cell nuclei in unprocessed specimens without staining is preferable; however, inevitable irregular surfaces in fresh tissues results in limitations. An ultraviolet metasurface with the ability to generate an ultraviolet optical focus maintaining < 1.1-µm in lateral resolution and ∼290 µm in depth of field (DOF) is proposed for fast, high resolution, label-free photoacoustic histological imaging of unprocessed tissues with uneven surfaces. Microanatomical characteristics of the cell nuclei can be observed, as demonstrated by the mouse brain samples that were cut by hand and a ∼3 × 3-mm2 field of view was imaged in ∼27 min. Therefore, ultraviolet metasurface-assisted photoacoustic microscopy is anticipated to benefit intraoperative pathological assessments and basic scientific research by alleviating laborious tissue preparations.

A Comment on: An Eocene army ant (2022) by Sosiak CE et al.

A Comment on: An Eocene army ant (2022) by Sosiak CE et al.

Influence of Al11Ce3 Size and Distribution on the Electrochemical Properties of Sonoprocessed Al-10 wt.% Ce Alloy

Solidification of Al–Ce alloys under ultrasonic vibrations (Sonoprocessing) has a significant effect on the refining of Al11Ce3 intermetallic, which plays a key role in controlling the properties of this group of high-performance characteristics. In the current research, a group of as-received Al-10 wt% Ce alloys that were sonoprocessed under different temperatures was characterized. The influence of Al11Ce3 intermetallic size and distribution on the electrochemical properties of these alloys was investigated. Polarization tests in 3.5% NaCl solution were carried out and the recorded Tafel and impedance curves were studied. The corrosion test results were related to the microstructure characteristics as affected by sonoprocessing. Investigation of the as-received samples showed that ultrasonic vibrations broke the long lath-shaped particles of Al11Ce3 and obviously decreased their size and increased their surface area fraction. Sonoprocessing at the optimum temperature, 655 °C, reduced the Al11Ce3 particles size by 90% and enhanced their distribution in the matrix. This in its turn resulted in significant effects on their electrochemical behavior. Polarization tests showed that the corrosion rate of the un-sonoprocessed specimen decreased from ~ 0.00068 to 0.00006 mm/year after processing at the optimum condition (655 °C), and the polarization resistance increased from ~ 71 to 343 kΩ. By increasing the temperature of ultrasonic treatment beyond 655 °C, and the corresponding coarsening of the intermetallic particles, the corrosion rate slowly increased again, and concurrently, the polarization resistance decreased. The size and distribution of the intermetallic particles also influenced the formation of the corrosion pits, where the optimum sample showed shallow pits compared to those observed in the unprocessed specimen. This emphasizes the role of sonoprocessing in controlling the microstructure features and hence the electrochemical properties of Al-10 wt% Ce alloys.

Proximate Composition of Thai and Cambodian Ready-to-Eat Insects

Samples of ready-to-eat snacks based on Lethocerus indicus, Gymnogryllus vietnamensis, Tarbinskiellus portentosus, Teleogryllus mitratus, Bombyx mori, Omphisa fuscidentalis, and Cybister limbatus were purchased in Cambodia and Thailand, and their proximate chemical composition (including Na and Cl) was analysed. Comparing the results with the few existing references from the literature (based on unprocessed specimens), marked differences occurred. This was expected as the insect chemical composition varies strongly intra- and interspecifically due to taxon, feeding, instar, and processing, among others. In general, the insects mainly consisted of fat (35 to 60%) and protein (25 to 38%), with 2 to 16% nitrogen-free extract, 2 to 15% fibre, 3 to 5% ashes, 0.4 to 1.6% Na, and 0.6 to 1.4% Cl (dry matter base). In this way, this contribution adds to the compositional knowledge about traditional insect-based foodstuffs. The combination of high fat and protein with low carbohydrates makes them suitable to combat nutrition disorders.

Three-dimensional virtual histology in unprocessed resected tissues with photoacoustic remote sensing (PARS) microscopy and optical coherence tomography (OCT)

Histological images are critical in the diagnosis and treatment of cancers. Unfortunately, current methods for capturing these microscopy images require resource intensive tissue preparation that may delay diagnosis for days or weeks. To streamline this process, clinicians are limited to assessing small macroscopically representative subsets of tissues. Here, a combined photoacoustic remote sensing (PARS) microscope and swept source optical coherence tomography system designed to circumvent these diagnostic limitations is presented. The proposed multimodal microscope provides label-free three-dimensional depth resolved virtual histology visualizations, capturing nuclear and extranuclear tissue morphology directly on thick unprocessed specimens. The capabilities of the proposed method are demonstrated directly in unprocessed formalin fixed resected tissues. The first images of nuclear contrast in resected human tissues, and the first three-dimensional visualization of subsurface nuclear morphology in resected Rattus tissues, captured with a non-contact photoacoustic system are presented here. Moreover, the proposed system captures the first co-registered OCT and PARS images enabling direct histological assessment of unprocessed tissues. This work represents a vital step towards the development of a rapid histological imaging modality to circumvent the limitations of current histopathology techniques.

DIAGNOSTIC PERFORMANCE OF ZIEHL-NEELSEN &amp; CBNAAT TECHNIQUES IN PULMONARY TUBERCULOSIS, A RETROSPECTIVE ANALYSIS AT TERTIARY CARE HOSPITAL IN JHALAWAR, RAJASTHAN.

Introduction: Tuberculosis (TB) remains a leading cause of death among infectious diseases worldwide. The advent of the CBNAAT was a revolution in the diagnosis of tuberculosis, especially with high incidence and resource poor regions. It can be used close to the point of care by operators with minimal technical expertise, enabling diagnosis of TB and rifampicin&#x0D; Resistance (RIF) concurrently using unprocessed clinical specimens, in less than 2h.&#x0D; Aim: To evaluate the diagnostic performances of Ziehl-Neelsen &amp; CBNAAT techniques in detection of Pulmonary Tuberculosis.&#x0D; Materials and Methods: We retrospectively reviewed the 2414 sputum samples of suspected pulmonary TB. Sputum samples were subjected for ZN staining and CBNAAT.RIF resistance was detected by CBNAAT.&#x0D; Results: Out of 2414 samples, 751 sputum samples were positive by smear microscopy. 1127 Samples were confirmed positive by CBNAAT examination. Majority of cases, 43.57% were in 21-40 yrs age group.24.40% were females and 75.59% were males. Sensitivity of CBNAAT was 100% for sputum positive cases and sensitivity was 22.6% for sputum negative cases. Overall RIF resistance was detected in 49 (4.4%) cases in present study.&#x0D; Conclusion: CBNAAT provide sensitive detection of tuberculosis and rifampicin resistance directly from untreated sputum in less than 2 hours with minimal hands-on time.&#x0D; Keywords: Cartridge-based nucleic acid amplification tests (CBNAAT), Rifampicin(RIF)

Clinical Assessment and Validation of a Rapid and Sensitive SARS-CoV-2 Test Using Reverse Transcription Loop-Mediated Isothermal Amplification Without the Need for RNA Extraction.

BackgroundAmid the enduring pandemic, there is an urgent need for expanded access to rapid, sensitive, and inexpensive coronavirus disease 2019 (COVID-19) testing worldwide without specialized equipment. We developed a simple test that uses colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) to detect severe acute resrpiratory syndrome coronavirus 2 (SARS-CoV-2) in 40 minutes from sample collection to result.MethodsWe tested 135 nasopharyngeal specimens from patients evaluated for COVID-19 infection at Massachusetts General Hospital. Specimens were either added directly to RT-LAMP reactions, inactivated by a combined chemical and heat treatment step, or inactivated then purified with a silica particle–based concentration method. Amplification was performed with 2 SARS-CoV-2-specific primer sets and an internal specimen control; the resulting color change was visually interpreted.ResultsDirect RT-LAMP testing of unprocessed specimens could only reliably detect samples with abundant SARS-CoV-2 (>3 000 000 copies/mL), with sensitivities of 50% (95% CI, 28%–72%) and 59% (95% CI, 43%–73%) in samples collected in universal transport medium and saline, respectively, compared with quantitative polymerase chain reaction (qPCR). Adding an upfront RNase inactivation step markedly improved the limit of detection to at least 25 000 copies/mL, with 87.5% (95% CI, 72%–95%) sensitivity and 100% specificity (95% CI, 87%–100%). Using both inactivation and purification increased the assay sensitivity by 10-fold, achieving a limit of detection comparable to commercial real-time PCR-based diagnostics.ConclusionsBy incorporating a fast and inexpensive sample preparation step, RT-LAMP accurately detects SARS-CoV-2 with limited equipment for about US$6 per sample, making this a potentially ideal assay to increase testing capacity, especially in resource-limited settings.

Anti-bacterial Properties of Wear Resistant Thermal Diffusion Coatings

Bacterial sensitivity of thermally diffused stainless steel grade 316L has been studied in this paper. Thermal diffusion heat treatment processes like salt bath nitriding and slurry paste boronizing have been explored for their anti-bacterial properties. SS316L has been chosen as the substrate material due to its acceptance as a general bio-material in the medical industry. The results from the surface hardness and cross section analysis of the treated specimens revealed their characteristic nitride and boride layers confirming the success of the nitriding and boronizing processes. Surface roughness, prior- and post-heat treatment were studied through tactile profilometer. Bacterial sensitivity tests were conducted on the treated and unprocessed specimens with Bacillus subtilis bacteria in nutrient agar. Upon incubating for 24 h, the tests displayed a distinct zone of inhibition adjacent to the treated specimens. Both the nitrided and borided SS316L specimens exhibited anti-bacterial behaviour in response to B. subtilis bacteria. These anti-bacterial surfaces can potentially prevent the formation of infectious biofilm on medical implants and devices.

High-temperature corrosion behavior of high-temperature and high-pressure cavitation processed Cr–Mo steel surface

In this paper, long-term high-temperature corrosion at 500 °C and high-temperature corrosion at the melting temperature of a corrosive ash mixture were examined because the use of high-temperature equipment such as boilers and gas turbines increases year over year. To investigate the optimum cavitation processing conditions for the specimens used in high-temperature corrosion tests, the surface properties of each processed specimen were examined. In specimens processed using multifunction cavitation (MFC), the compressive residual stress was high when the processing time was 10 min and the Cr content on the surface was greater than on the surface of an unprocessed specimen. On the other hands, in specimens subjected to water-jet peening (WJP), the compressive residual stress was high when the processing time was 10 min. In the present study, the processing time was selected to be 10 min and all high-temperature corrosion tests were conducted by the coating method. In the case of long-term high-temperature corrosion at 500 °C, the corrosion loss of the MFC-processed and WJP-processed specimens was small, whereas the corrosion loss of the unprocessed specimen was large.

A Portable Smartphone-linked Device for Direct, Rapid and Chemical-Free Hemoglobin Assay

We describe the development and clinical evaluation of an automated smartphone-linked sensor capable of chemical-free, quantitative measurement of hemoglobin concentration ([Hb]) in whole blood samples. We have demonstrated that our sensor could analyze an unprocessed blood specimen with a mean processing time of <8 s and provided the [Hb] results with ~99% accuracy against a reference hematology analyzer with coefficient of variation (CV) of 1.21% measured at [Hb] = 11.2 g/dL. Its diagnostic capability for anemia was evaluated by measuring [Hb] of 142 clinical blood specimens and comparing the results with those from an automated hematology analyzer (ADVIA 2120i, Siemens AG, Germany) and a portable hemoglobinomteter (Hb201+, Hemocue, Sweden). The sensor yielded comparable sensitivities and specificities of 87.50% and 100.00% for males, and 94.44% and 100.00% for females, respectively, for anemic detection. The results suggested that our optical sensor based on the intrinsic photothermal response of Hb molecules and advances in consumer electronics, particularly smartphone capabilities, enables a direct, chemical-free [Hb] assay accessible to people in both developed and developing countries.

Reduction of Human DNA Contamination in Clinical Cerebrospinal Fluid Specimens Improves the Sensitivity of Metagenomic Next-Generation Sequencing.

Metagenomics next-generation sequencing (mNGS) is increasingly available for the detection of obscure infectious diseases of the central nervous system. However, human DNA contamination from elevated white cells, one of the characteristic cerebrospinal fluid (CSF) features in meningitis patients, greatly reduces the sensitivity of mNGS in the pathogen detection. Currently, effective approaches to selectively reduce host DNA contamination from clinical CSF samples are still lacking. In this study, a total of 20 meningitis patients were enrolled, including 10 definitively diagnosed tuberculous meningitis (TBM) and 10 definite cryptococcal meningitis (CM) cases. To evaluate the effect of reduced human DNA in the sensitivity of mNGS detection, three specimen-processing protocols were performed: (i) To remove human DNA, saponin, a nonionic surfactant, was used to selectively lyse white cells in CSF followed by DNase treatment prior to the extraction of DNA; (ii) to reduce host DNA, CSF was centrifuged to remove human cells, and the supernatant was collected for DNA extraction; and (iii) DNA extraction from the unprocessed specimens was set as the control. We found that saponin processing significantly elevated the NGS unique reads for Cryptococcus (P < 0.01) compared with the control but had no effects for Mycobacterium tuberculosis (P > 0.05). However, detection of centrifuged supernatants improved the NGS unique reads for both TBM and CM compared with controls (P < 0.01). Our results demonstrate that the use of mNGS of centrifuged supernatants from clinical CSF samples in patients with TBM and CM is a simple and effective method to improve the sensitivity of pathogen detection.

Prospective Evaluation of HIV Testing Technologies in a Clinical Setting: Protocol for Project DETECT

BackgroundHIV testing guidelines provided by the Centers for Disease Control and Prevention (CDC) are continually changing to reflect advancements in new testing technology. Evaluation of existing and new point-of-care (POC) HIV tests is crucial to inform testing guidelines and provide information to clinicians and other HIV test providers. Characterizing the performance of POC HIV tests using unprocessed specimens can provide estimates for the window period of detection, or the time from HIV acquisition to test positivity, which allows clinicians and other HIV providers to select the appropriate POC HIV tests for persons who may be recently infected with HIV.ObjectiveThis paper describes the protocols and procedures used to evaluate the performance of the newest POC tests and determine their sensitivity during early HIV infection.MethodsProject DETECT is a CDC-funded study that is evaluating POC HIV test performance. Part 1 is a cross-sectional, retrospective study comparing behavioral characteristics and HIV prevalence of the overall population of the Public Health–Seattle & King County (PHSKC) Sexually Transmitted Disease (STD) Clinic to Project DETECT participants enrolled in part 2. Part 2 is a cross-sectional, prospective study evaluating POC HIV tests in real time using unprocessed whole blood and oral fluid specimens. A POC nucleic acid test (NAT) was added to the panel of HIV tests in June 2018. Part 3 is a longitudinal, prospective study evaluating seroconversion sensitivity of POC HIV tests through serial follow-up testing. For comparison, HIV-1 RNA and HIV-1/HIV-2 antigen/antibody tests are also performed for participants enrolled in part 2 or 3. A behavioral survey that collects information about demographics, history of HIV testing, STD history, symptoms of acute HIV infection, substance use, sexual behaviors in the aggregate and with recent partners, and use of pre-exposure prophylaxis and antiretroviral therapy is completed at each part 2 or 3 visit.ResultsBetween September 2015 and March 2019, there were 14,990 Project DETECT–eligible visits (part 1) to the PHSKC STD Clinic resulting in 1819 part 2 Project DETECT study visits. The longitudinal study within Project DETECT (part 3) enrolled 27 participants with discordant POC test results from their part 2 visit, and 10 (37%) were followed until they had fully seroconverted with concordant positive POC test results. Behavioral survey data and HIV test results, sensitivity, and specificity will be presented elsewhere.ConclusionsStudies such as Project DETECT are critical for evaluating POC HIV test devices as well as describing characteristics of persons at risk for HIV acquisition in the United States. HIV tests in development, including POC NATs, will provide new opportunities for HIV testing programs.International Registered Report Identifier (IRRID)RR1-10.2196/16332

Performance evaluation of four point-of-care HIV tests using unprocessed specimens

BackgroundThe performance of recently approved point-of-care (POC) HIV tests should be assessed using unprocessed specimens. ObjectiveTo evaluate the sensitivity and specificity of four POC HIV tests using whole blood (WB) and two using oral fluid (OF) among persons recruited from health clinics in Seattle, Washington, during September 2015-September 2017. Study designParticipants were tested with the POC tests, additional plasma and serum were collected for laboratory testing, and participant- reported use of antiretroviral therapy (ART) or pre-exposure prophylaxis (PrEP) was recorded. Participants testing negative on all tests could reenroll every 90 days. Specimens from persons previously diagnosed with HIV infection as well as from those who were newly diagnosed during the study were included in the sensitivity estimate. Sensitivity and specificity were calculated based on HIV status determined by laboratory testing. ResultsOf 1,256 visits, 179 were from persons with HIV infection; 120 of these were taking ART. Among 1,077 visits from participants not diagnosed with HIV, PrEP use was reported at 155 (14.4%) visits. Sensitivity was similar among POC WB tests (95.53%-97.21%; p>0.05). Among participants on ART, sensitivity was lower for the same test performed on OF compared to WB (p<0.003). Specificity was high for all tests (99.44%- 100.00%); we did not detect specificity differences with PrEP use. ConclusionsThese POC tests displayed relatively high sensitivity and specificity using unprocessed specimens, suggesting their effectiveness in identifying HIV infections whenever laboratory-based testing is not feasible. Nonetheless, clients with recent risk should retest to rule out the possibility of a false-negative result.

Effect of Post Treatment on the Microstructure, Surface Roughness and Residual Stress Regarding the Fatigue Strength of Selectively Laser Melted AlSi10Mg Structures

This paper focusses on the effect of hot isostatic pressing (HIP) and a solution annealing post treatment on the fatigue strength of selectively laser melted (SLM) AlSi10Mg structures. The aim of this work is to assess the effect of the unprocessed (as-built) surface and residual stresses, regarding the fatigue behaviour for each condition. The surface roughness of unprocessed specimens is evaluated based on digital light optical microscopy and subsequent three-dimensional image post processing. To holistically characterize contributing factors to the fatigue strength, the axial surface residual stress of all specimens with unprocessed surfaces is measured using X-ray diffraction. Furthermore, the in-depth residual stress distribution of selected samples is analyzed. The fatigue strength is evaluated by tension-compression high-cycle fatigue tests under a load stress ratio of R = −1. For the machined specimens, intrinsic defects like pores or intermetallic phases are identified as the failure origin. Regarding the unprocessed test series, surface features cause the failures that correspond to significantly reduced cyclic material properties of approximately −60% referring to machined ones. There are beneficial effects on the surface roughness and residual stresses evoked due to the post treatments. Considering the aforementioned influencing factors, this study provides a fatigue assessment of the mentioned conditions of the investigated Al-material.

An Experimental Study of Fracture Toughness for Nano/Ultrafine Grained Al5052/Cu Multilayered Composite Processed by Accumulative Roll Bonding

In this study, ultrafine grained Al5052/Cu multilayered composite has been produced by accumulative roll bonding (ARB) and fracture properties have been studied using plane stress fracture toughness. The fracture toughness has been investigated for the unprocessed specimens, primary sandwich and first, second, and third cycles of ARB process by ASTM E561 and compact tension (CT) specimens. Also, the microstructure and mechanical properties have been investigated using optical microscopy, scanning electron microscopy, uniaxial tensile tests, and microhardness measurements. The value of plane stress fracture toughness for the ultrafine grained Al5052/Cu composite increased by increasing the number of ARB cycles, continuously from the primary sandwich to end of the third cycle. The maximum value of 59.1 MPa m1/2 has been obtained that it is about 2.77 and 4.05 more than Al5052 and pure Cu (unprocessed specimens). This phenomenon indicated that ARB process and the addition of copper to aluminum alloy could increase the value of fracture toughness to more than three times. The results showed that by increasing the ARB cycles, the thickness of copper layers reduced and after the fifth cycle, the excellent uniformity of Cu layers achieved. By increasing the number of ARB cycles, the microhardness of both aluminum and copper layers have been significantly increased. The tensile strength of the sandwich has been enhanced continually, and the maximum value of 566.5 MPa has been achieved.

Unmounted Doesn’t Mean Unprocessed: A Case Study of Exporting Australian Herbarium Specimens

In 2017, two incoming international herbarium loans were confiscated and destroyed by the Commonwealth Department of Agriculture and Water Resources (DAWR). Following these regrettable incidents, communication has improved between Managers of Australasian Herbarium Collections (MAHC) and Plant Import Operations Branch of DAWR. The outcome is that new protocols now exist for shipment of plant material between herbaria based on the recognition by DAWR that all herbarium specimens are in fact processed (pressed, dried and frozen) even if they are not fully mounted (Brown et al, this conference). Simultaneously, the United States Department of Agriculture (USDA) had been reported to be destroying incoming unmounted specimens, thus making it difficult to send unmounted exchange material overseas, and particularly to the USA. Using the documentation developed for incoming overseas loans by MAHC and, encouraging the receiving institution in the USA to acquire a USDA 588 Importing Permit for unprocessed plant specimens (non-loan, unmounted herbarium specimens), it was possible to export unmounted herbarium specimens and dried DNA samples into the USA. Excluding the USA specific requirements, we were also able to export exchange material and dried DNA samples to Singapore and Sweden.

Dynamic Strength of a Titanium Alloy with an Electron-Beam-Modified Surface

Data are presented of plane-wave experiments aimed at determining the dynamic strength of 3M titanium alloy with a surface processed by a microsecond electron beam. It has been found that the dynamic strength of processed specimens is higher than that of unprocessed specimens. Metallographic examination of test specimens has revealed spallation macrofracture inside the unprocessed specimens and spallation microfracture at the interface between the hardened layer and the substrate in the beam-processed specimens.

Virtual brain tumor histopathology and immunohistochemistry with stimulated raman scattering microscopy.

e13511 Background: Stimulated Raman scattering (SRS) microscopy is a label-free optical technique which uses the chemical composition of fresh tissue to generate image contrast. Prior work has demonstrated exceptional correlation between SRS images and H&amp;E microscopy for detecting brain tumor infiltration ex vivo. However, SRS has not previously been suitable for a clinical environment. Further, SRS has utilized structural, rather than chemical, diagnostic features. We present the first clinical validation of SRS, as well as our work towards mutation-targeted SRS imaging. Methods: Implementation of SRS with a fiber laser source allowed sufficient stability for clinical deployment. Unprocessed specimens from 200 neurosurgical cases were imaged at the CH2 and CH3 vibrational modes, then processed to mimic the appearance of H&amp;E staining. 30 cases were trialed in a simulated intraoperative consultation to assess concordance between SRS and cryosection microscopy. A multi-layer perceptron (MLP) model was then used to predict brain tumor diagnosis based on quantified image attributes. To explore the potential for chemically specific SRS, isogenic lines of normal human astrocyte were prepared, differing by the presence or absence of the R132H mutation in the isocitrate dehydrogenase 1 (IDH1) gene. IDH1 R132H cells accumulate high concentrations of the oncometabolite 2-hydroxyglutarate and display predictably altered metabolism. 200 Raman spectra were collected from 50 wild type (WT) and 50 R132H cells with the aim of detecting these changes. Each cell line was then submitted for targeted metabolomic analysis. Results: Excellent concordance was observed between SRS and frozen section histology ( κ &gt;0.89). The MLP diagnosed brain tumor subtype with 90% accuracy. A robust spectral difference was observed between wild type and R132H cells, which showed concordance with metabolomic data. Conclusions: The diagnostic capability, ease of use and speed of SRS make it well-suited for integration into the operative workflow. Further, because SRS amplifies the Raman signal with no resonant background, the spectral differences observed may allow rapid differentiation of IDH1 WT and R132H cells with SRS.