Selective laser nano-thermolysis of human leukemia cells with microbubbles generated around clusters of gold nanoparticles.

Background And Objective: Previously reported studies on laser nano-thermolysis of cancerous cells demonstrated insufficient efficacy and specificity of malignant cell damage. Safety, that is, absence of damage to normal cells in the course of the laser thermolysis was also low due to less than optimal protocol of cancer cell targeting with nanoparticles (NP). The objective of this study was two-fold: to optimize NP targeting to real tumor (human) cells and to better understand physical mechanisms of cell damage for improved control of the laser ablation.

Method of laser activated nano-thermolysis for elimination of tumor cells.

We describe novel ex vivo method for elimination of tumor cells from cell suspension, Laser Activated Nanothermolysis and propose this method for purging of bone marrow and blood transplants. K562 and human lympholeukemia cells were eliminated in experiments by laser-induced micro-bubbles that emerge inside individual target cells around selectively formed clusters of light-absorbing gold nanoparticles. Pretreatment of tumor cells with specific monoclonal antibodies and Ig-conjugated 30-nm gold particles allowed the formation of clusters of 10-20 on the surface of cell membrane.

Photothermal responses of individual cells.

Photothermal (PT) responses of individual intact cells are studied with a thermal lens dual-laser scheme. A multiparameter model for analysis of PT responses as a function of cell size, structure, and optical properties is suggested and verified experimentally for living cells, red blood cells, lymphocytes, tumor cells (K 562), hepatocytes, and miocytes, by applying pulsed laser radiation at 532 nm for 10-ns duration. PT responses for noninvasive and damaging modes of laser-cell interaction are investigated.

Influence of physiological conditions on laser damage thresholds for blood, heart, and liver cells.

Background And Objectives: Damage to blood and other tissues during laser interventions depends mainly upon absorption of laser radiation by cells. The objective of this work was to evaluate the influence tissue-specific physiological factors on photo-damage thresholds of individual cells: Red blood cells (blood), hepatocytes (liver), and miocytes (heart).

Study Design/materials And Methods: Laser-induced damage to individual cells was detected and studied with Laser Load Test (LLT).

Photothermal detection of laser-induced damage in single intact cells.

Background And Objective: Most of the studies of laser-induced damage do not analyze individual cells. Objective of this work was to evaluate local photo-induced thermal phenomena in single cells at theoretical and experimental levels for developing the method for real-time detection of laser damage in intact cells.

Study Design/materials And Methods: Theoretical model of cell-laser interaction assumes local nature of photo-induced thermal effects and describes photodamage through bubble formation.