Background: The clinical efficiency of laser treatments is limited by the low penetration of visible light used in certain procedures like photodynamic therapy (PDT). Second Harmonic Generation (SHG) PDT is an innovative technique to overcome this limitation that enables the use of Near Infrared (NIR) light instead of visible light. NIR frequency bands present an optical window for deeper penetration into biological tissue. In this research, we compare the penetration depths of 405 and 808 nm continuous wave (CW) lasers and 808 nm pulsed wave (PW) laser in two different modes (high and low frequency). Methods: Increasing thicknesses of beef and chicken tissue samples were irradiated under CW and PW lasers to determine penetration depths. Results: The 808 nm CW laser penetrates 2.3 and 2.4 times deeper than the 405 nm CW laser in beef and chicken samples, respectively. 808 nm PW (pulse frequency—500 Hz) penetrates deeper than CW laser at the same wavelength. Further, increasing the pulse frequency achieves higher penetration depths. High frequency 808 nm PW (pulse frequency—71.4 MHz) penetrates 7.4- and 6.0-times deeper than 405 nm CW laser in chicken and beef, respectively. Conclusions: The results demonstrate the higher penetration depths of high frequency PW laser compared to low frequency PW laser, CW laser of the same wavelength and CW laser with half the wavelength. The results indicate that integrating SHG in the PDT process along with pulsed NIR light may allow the treatment of 6–7 times bigger tumours than conventional PDT using blue light.

The vast majority of cancer related deaths are caused by metastatic tumors. Therefore, identifying the metastatic potential of cancer cells is of great importance both for prognosis and for determining the correct treatment. Infrared (IR) spectroscopy of biological cells is an evolving research area, whose main aim is to find the spectral differences between diseased and healthy cells. In the present study, we demonstrate that Attenuated Total Reflection Fourier Transform IR (ATR-FTIR) spectroscopy may be used to determine the metastatic potential of cancer cells. Using the ATR-FTIR spectroscopy, we can identify spectral alterations that are a result of hydration or molecular changes. We examined two murine melanoma cells with a common genetic background but a different metastatic level, and similarly, two human melanoma cells. Our findings revealed that higher metastatic potential correlates with membrane hydration level. Measuring the spectral properties of the cells allows us to determine the membrane hydration levels. Thus, ATR-FTIR spectroscopy has the potential to help in cancer metastasis prognosis.

The acid‐base, spectroscopic, photophysical and liposome‐binding properties of the recently synthesized free base, 29H,31H,1,4,8,11,15,18,22,25‐octafluoro‐2,3,9,10,16,17,23, 24‐octakisperfluoro(isopropy1) phthalocyanine, F₆₄PcH₂, are reported. The perfluoroalkylation of the phthalocyanine core renders the hydrogen atoms acidic, with a pK_a= 6. The F₆₄Pc^‐2 dianion is detected already at pH 3, by singular‐value decomposition analysis of electronic spectra. F₆₄Pc^‐2 generates ¹O₂ with quantum yields Φ_Δ= 0.252 (in MeOH) and 0.019 in liposomes. Metallation of the Pc macrocycle to yield F₆₄PcZn increases Φ_Δ to 0.606 and 0.126 in MeOH and liposomes, respectively. Surprisingly, F₆₄Pc^‐2 (but not F₆₄PcH₂ or F₆₄PcZn) binds strongly to liposomes, with a binding constant K_b= 25 (mg/mL)^‐1. The fully protonated F₆₄PcH₂, but not the zwitterionic F₆₄Pc^‐2, might favor hydrogen bonding, thus reducing its lipophilicity. Similarly, the Lewis acidity of Zn in F₆₄PcZn, and thus its ability to bind water within a hydrophobic perfluoroalkyl pocket, is significantly enhanced by the fluorinated substituents.

Objective: Pandemic outbreaks necessitate effective responses to rapidly mitigate and control the spread of disease and eliminate the causative organism(s). While conventional chemical and biological solutions to these challenges are characteristically slow to develop and reach public availability; recent advances in device components operating at Super High Frequency (SHF) bands (3–30 GHz) of the electromagnetic spectrum enable novel approaches to such problems. Methods: Based on experimentally documented evidence, a clinically relevant in situ radiation procedure to reduce viral loads in patients is devised and presented. Adapted to the currently available medical device technology to cause viral membrane fracture, this procedure selectively inactivates virus particles by forced oscillations arising from Structure Resonant Energy Transfer (SRET) thereby reducing infectivity and disease progression. Results: Effective resonant frequencies for pleiomorphic Coronavirus SARS-CoV-2 is calculated to be in the 10–17 GHz range. Using the relation y = -3.308x + 42.9 with x and y representing log₁₀ number of virus particles and the clinical throat swab Ct value respectively; in situ patient–specific exposure duration of ~15x minutes can be utilized to inactivate up to 100% of virus particles in the throat-lung lining, using an irradiation dose of 14.5 ± 1 W/m²; which is within the 200 W/m² safety standard stipulated by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Conclusions: The treatment is designed to make patients less contagious enhancing faster recoveries and enabling timely control of a spreading pandemic. Advances in knowledge: The article provides practically applicable parameters for effective clinical adaptation of this technique to the current pandemic at different levels of healthcare infrastructure and disease prevention besides enabling rapid future viral pandemics response.