自1970年Arthur Ashkin研究出利用雷射光為基礎的捕捉技術後，雷射光鉗（optical tweezers）便開始不斷創新發展進步。近年來，雷射光鉗為一種研究細胞體內與體外機械特性的技術工具，例如量測細胞質的黏彈性（viscoelasticity）及細胞裡外的複數形式的剪力模數（complex shear modulus）等。本研究先行架設雷射光鉗系統，以一道雷射光分光為一捕捉光和一偵測光來達到偵測微球於介質中布朗運動的目的。本研究欲改善之前量測黏度相關研究中利用捕捉推測大小及形狀的胞器而使黏度等物理特性為推算值的部份，利用抓取送入免疫細胞RAW 264.7內直徑約2 μm的聚苯乙烯微球（polystyrene bead）以直接量測免疫細胞RAW 264.7內的黏度並使用Selhuber-Unkel等人所使用的表示方法來呈現介質的黏度[1]，接著加入抗癌藥物–紫杉醇（Paclitaxel）觀測免疫細胞因藥物造成黏度的改變。
進行研究之前，需先行量測自組裝光鉗系統的參數，例如光鉗的彈性係數及光四象限二極體的電壓–位移轉換因子–β等。本研究利用固定微球方法（stuck bead method）以及兩種以能量頻譜為基礎來計算的方法求得β值，而光鉗鋼性係數的量測分別使用能量頻譜（power spectral density）、能量均分定理（equipartition）及波茲曼分佈（Boltzman distribution）來分析。了解此系統的物理參數後，隨後利用此系統針對已知液體的黏度做量測，結果發現相符合。隨後進行量測正常免疫細胞的黏度並與相關文獻比較，再加入紫杉醇與細胞共培養，量測細胞在藥物累積下的黏度變化。
本研究發現當藥物累積，免疫細胞的黏度會越來越小，一開始3小時間黏度會大幅度的改變到最後趨於平穩的狀態。除此之外，本研究藉由細胞的型態以及共軛焦掃描顯微鏡的判斷，推測透過本實驗亦可觀測到細胞走向細胞凋亡的過程。本研究推測在200 nM濃度下的紫杉醇，加藥後0.5-1小時的時間應為藥物作用於細胞的時間，而1-3小時開始有細胞內溶解酵素的參與分解細胞骨架，3-8.5小時後，免疫細胞走向細胞凋亡。本研究希冀提供未來藉由量測細胞的黏度來看藥物對於細胞是否走向細胞凋亡的方法。

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