Journal of Biophotonics focuses on the interdisciplinary field of biophotonics, publishing cutting-edge research on interactions between light and biological material. The journal covers photonics research in areas such as life sciences, medicine and biomedicine, environmental science, nutrition, biology, physics, and chemistry, ranging from fundamental research to the latest clinical applications.

We introduce a virtual-point-based deconvolution technique designed to enhance the spatial resolution of OR-PAM images. This approach utilizes a novel genetic algorithm, combined with a pixel-level loss function and smoothness regularization, to iteratively refine the positioning of virtual point sources. The aim is to closely approximate the actual distribution of photoacoustic point sources.

This study unveils the optimal spatial offsets for transcutaneous bone measurements using spatially offset Raman spectroscopy (SORS), employing a novel forward-adjoint Monte Carlo multi-layer (MCML) model to enhance noninvasive bone health diagnostics. Findings reveal that optimal offsets vary with tissue characteristics, promising significant advancements in medical applications.

Our study employed multiphoton microscopy to establish the optical pathological characteristics of endometrioid adenocarcinoma, demonstrating its label-free ability to differentiate between benign endometrial hyperplasia and cancerosis. Furthermore, it enabled quantitative assessment of tumor microenvironment alterations by analyzing collagen signatures in endometrial stromal tissue.

General flowchart of the article.

In thyroid surgery, there is a risk of inadvertently removing the parathyroid glands. At present, there is a lack of research on using Raman spectroscopy to discriminate parathyroid and thyroid tissues. The objective of this study is to discriminate thyroid and parathyroid tissues using Raman spectroscopy combined with an improved support vector machine (SVM) algorithm. The results show that the sensitivity of this algorithm is 94.67% and the accuracy is 94.44%.

The anisotropy factor (g) of tumor phantom embedded with 40 μg/mL gold nanorods (GNRs) decreased by ~43% compared to the phantom with 10 μg/mL GNRs, which leads to a decrease in forward scattering and penetration of light. For the phantom incorporated with 40 μg/mL GNRs on increasing the phantom thickness from 600 to 1800 μm, the g is reduced by 47%. The glycerol doses ranging from 10% to 40% can increase the g of a tumor phantom embedded with GNRs by 44% and enhance the penetration of light.

This paper proposes an enhanced multimode phase imaging method based on the TIE to perform multimode contrast-enhanced observation of unstained specimens. First, quantitative phase results of biological samples are obtained by solving the TIE, and then optimal ZPC and isotropic DIC images are obtained. Application of the algorithm to real and simulated objects shows significant feasibility and accuracy. Experiments on MCF-7 cells resulted in multimode images of cells with structures not visible in the raw intensity images. The algorithm is simple to implement and can be combined with traditional optical microscopy.

In this study, we utilized an optical-resolution photoacoustic microscopy imaging system to conduct photoacoustic imaging on an agar phantom with elastic differences and liver tissue after microwave ablation. By performing cross-correlation calculations, we obtained the distribution of elastic characteristics. The results highlight the potential of the photoacoustic system in investigating the elastic properties of microwave-ablated tissues, presenting a novel approach for disease diagnosis and pathological tissue analysis.

The challenges posed by using of two nonidentical microscope objective (MO) in two arms of a Linnik type interferometer are resolved by using a single MO based compact Linnik interferometer. Hyperspectral quantitative phase microscopy (QPM) is performed using the developed setup, which enables advanced classification of different cellular components.

Traditional imaging techniques exhibit certain limitations in the early diagnosis of diabetic retinopathy. This study confirms the potential of Raman spectroscopy for the early diagnosis of diabetic retinopathy at the animal level.

A total of 734 nm near-infrared (NIR) light induces senescence in cancer cells, accompanied by increased reactive oxygen species, mitochondrial membrane potential and intracellular calcium levels. Non-cancer cells show no senescence effect under similar conditions. This study highlights the potential of NIR light in selectively targeting cancer cells while sparing non-cancer ones.

C-OCE allowed to establish that with longitudinal stretching of the small-intestine wall, ruptures appear first in the longitudinal muscle layer and then in the circumferential muscle layer, while submucosa and mucosa are more tolerant to stretching. A threshold of ~15%, defined for the longitudinal muscle layer, has been proposed as a practical safety criterion.

The study compares healthy and tumor breast tissue in mice using spectroscopy, refractometry, and Raman spectroscopy. The findings show that tumor tissue has lower scattering and refractive indices and altered molecular composition. The difference in the optical parameters of the tissues makes it possible to reliably differentiate them.

A near-infrared spectroscopic device was developed for the real-time monitoring of hemodynamic changes during coronary artery occlusion in the rat heart. This was evidenced by a rapid decrease in ΔHbO and a marked increase in ΔHbR when rats' myocardial ischemia occurred, accompanied by a significant elevation of the electrocardiographic ST segments. It has also yielded new insights for monitoring ischemic heart disease.

This study explores the combined use of polydioxanone threads and red LED photobiomodulation therapy (PBM) for reducing glabellar static wrinkles. Conducted on 40 individuals, the trial examines the effects one session on the control of post procedure swelling and also the effect of nine sessions over 30 days on the increase in dermal thickening provided by the thread. The PBM effect on thread hydrolysis was also evaluated.

Collagen morphological features can be extracted from second-harmonic generation (SHG) images, but dependence to the experimental conditions represents a significant issue. This problem has been tackled by acquiring SHG images of the same collagenous sample in various laboratories, using different setups and conditions, and by comparing their extracted features. They strongly depend by specific experimental parameters; hence, a preprocessing method has been proposed and successfully tested for comparing results obtained in different labs.

The study investigated the protective function of skin surface lipids (SSLs) against solar radiation and evaluated the effectiveness of a solar filter on SSLs composition and hydration kinetics in the stratum corneum. Results indicated that SSLs absorb solar light and help maintain water balance, but their protective function can be limited due to variation in distribution. Using a solar filter helped preserve SSLs and water balance, demonstrating the importance of supplementary measures for comprehensive skin protection.

Photobiomodulation (PBM) using 460 nm blue light has been shown to have an inhibitory effect on skin cancer cells. We found that blue light inhibits these melanoma cells through oxidative stress and DNA damage, and this inhibition intensifies at higher irradiance levels. Although the cells initially attempt to resist the stress induced by the treatment, they eventually undergo apoptosis over time.

Supplementation with macular pigment carotenoids increased overall serum carotenoids content and this increase was highest in patients with initial high baseline carotenoid content. Clear distinction in structural profile of serum carotenoids pre and post supplementation was noted, indicating Raman spectroscopy can potentially differentiate and quantify carotenoids in blood.

Raman spectroscopy was used for noninvasive diagnosis of skin melanoma. With spectra data containing autofluorescence, machine learning obtained higher accuracy to classify different skin lesions compared to the pure Raman spectra data without autofluorescence. This demonstrates that the autofluorescence background in Raman spectra holds diagnostic value.