The authors gratefully acknowledge the equipment grant from the Natural Science and Engineering Research (NSERC) Council of Canada for HPLC, the operating grant from the Canadian Institute of Health Research (CIHR) and Canadian Breast Cancer Research (CBCR) Alliance to X.Y. Wu, and the University of Toronto Scholarship to R.X. Zhang and T. Zhang.

All animal experiments were approved by the Animal Care Committee of University Health Network at the Ontario Cancer Institute and conducted in accordance with the Canadian Council on Animal Care Guidelines.
1. Biological Sample Preparation
<ol>
	<li>Collect the whole blood, major organs, and breast tumor at predetermined time-points after intravenous (i.v.) administration of drug-containing formulations (e.g., DMPLN, liposomal DOX)
	<ol>
		<li>Inject a breast tumor...

The authors have no competing financial interests and conflicts of interest.

Compared to other chromatographic methods that enable the detection of a single drug species at a time, the present HPLC protocol is able to simultaneously quantitate three drug compounds (DOX, MMC, and DOXol) in the same biological matrix without the need to change the mobile phase. This preparation and analysis method has been successfully applied to determine the pharmacokinetics and bio-distribution of two nanoparticle-based drug delivery systems (i.e., liposomal DOX and DMPLN)22. Sin...

Chemotherapy is a primary treatment modality for many cancers yet it is often associated with severe adverse effects and limited efficacy due to drug resistance and other factors1,2,3. To improve the outcome of chemotherapy, drug combination regimens have been applied in the clinic based on considerations such as non-overlapping toxicities, different mechanisms of drug action, and non-cross drug resistance4,5,6. In clinical trials, a better tumor response rate was often observed using simultaneously administered drug combinations compared to a regimen of sequential drug delivery7,8. However, due to sub-optimal bio-distribution of free drug forms, simultaneous injection of multiple drugs can cause prominent normal tissue toxicity that outweighs the therapeutic effect9,10,11. Nanocarrier-based drug delivery has been shown to alter the pharmacokinetics and bio-distribution of encapsulated drugs, enhancing tumor-targeted accumulation12,13,14. As reviewed in our recent articles, nanoparticles co-loaded with synergistic drug combinations have demonstrated the capability to mitigate the problems encountered by free drug combinations, due to their controlled temporal and spatial co-delivery of multiple drugs to tumor tissue, enabling synergistic drug effects against cancer cells4,15,16. As a result, superior therapeutic efficacy and low toxicity have been demonstrated in both pre-clinical and clinical studies4,17,18.
Our previous in vitro studies found that the combination of two anticancer drugs, doxorubicin (DOX) and mitomycin C (MMC), produced a synergistic effect against several breast cancer cells lines and, furthermore, co-loading DOX and MMC within polymer-lipid hybrid nanoparticles (DMPLN) overcame various multi-drug resistant associated efflux pumps (e.g., P-glycoprotein and breast cancer resistant protein)19,20,21. In vivo, DMPLN enabled spatial-temporal co-delivery of DOX and MMC to tumor sites and increased bioavailability of drugs within cancer cells, as indicated by moderation of the formation of the DOX metabolite doxorubicinol (DOXol)22. As a result, the DMPLN enhanced tumor cell apoptosis, tumor growth inhibition, and prolonged host survival compared to free DOX and MMC combination or a liposomal DOX formulation22,23,24,25.
Analyzing the actual amount of drugs co-delivered by a nanocarrier is critical for designing effective nanoparticle formulations. Many methods have been developed to analyze the plasma level of single DOX or MMC doses using high performance liquid chromatography (HPLC) alone or in combination with mass spectrometry (MS)26,27,28,29,30,31,32,33,34. However, these methods are often time-consuming and impractical for combination therapy as a large number of biological samples need to be prepared separately for analysis of multiple drugs (sometimes including drug metabolites). In addition to the strong plasma protein binding of DOX and MMC, red blood cells also have a great capacity to bind and concentrate many anticancer drugs35,36. Thus, plasma analysis for DOX or MMC may obfuscate actual blood drug concentrations. The present work (Figure 1) describes a simple and robust multiple drug analysis method using reverse phase HPLC to simultaneously extract and quantitate DOX, MMC and the DOX metabolite doxorubicinol (DOXol) from whole blood and various tissues (e.g., tumors). It has been successfully applied to determine the pharmacokinetics and bio-distribution of DOX and MMC as well as the formation of DOXol after drug delivery via free solutions or nanoparticle forms (i.e., DMPLN and liposomal DOX) in an orthotopically implanted murine breast-tumor mouse model after intravenous (i.v.) injection22.

<table style="border-collapse:collapse;width:635pt" width="846">
	<colgroup>
		<col style="width:188pt" width="250" />
		<col style="width:122pt" width="162" />
		<col style="width:89pt" width="119" />
		<col style="width:236pt" width="315" />
	</colgroup>
	<tbody>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Doxorubicin&#160;</td>
			<td class="xl20" style="width:122pt" width="162">Polymed Theraeutics</td>
			<td class="xl20" style="width:89pt" width="119">111023</td>
			<td class="xl20" style="width:236pt" width="315">Anticancer drug</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Mitomycin C</td>
			<td class="xl20" style="width:122pt" width="162">Polymed Theraeutics</td>
			<td class="xl20" style="width:89pt" width="119">060814</td>
			<td class="xl20" style="width:236pt" width="315">Anticancer drug</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl20" height="42" style="width:188pt;height:31.5pt" width="250">Doxorubicinol (DOXol)</td>
			<td class="xl20" style="width:122pt" width="162">Toronto Research Chemicals</td>
			<td class="xl20" style="width:89pt" width="119">D558020</td>
			<td class="xl21">Metabolite of DOX</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">4-Methylumbelliferone sodium salt&#160;</td>
			<td class="xl20" style="width:122pt" width="162">Sigma-Aldrich</td>
			<td class="xl20" style="width:89pt" width="119">M1508</td>
			<td class="xl21">Internal standard</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Myristic Acid</td>
			<td class="xl20" style="width:122pt" width="162">Sigma-Aldrich</td>
			<td class="xl20" style="width:89pt" width="119">544-63-8&#160;&#160;</td>
			<td class="xl21">Materials for poly-lipid hybrid nanoparticles</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Polyoxyethylene (100) Stearate</td>
			<td class="xl20" style="width:122pt" width="162">Spectrum</td>
			<td class="xl20" style="width:89pt" width="119">M1402</td>
			<td class="xl21">Materials for poly-lipid hybrid nanoparticles</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Polyoxyethylene (40) Stearate</td>
			<td class="xl20" style="width:122pt" width="162">Sigma-Aldrich</td>
			<td class="xl20" style="width:89pt" width="119">P3440</td>
			<td class="xl21">Materials for poly-lipid hybrid nanoparticles</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Pluronic F68 (PF68)</td>
			<td class="xl20" style="width:122pt" width="162">BASF Corp.</td>
			<td class="xl20" style="width:89pt" width="119">9003-11-6</td>
			<td class="xl21">Materials for poly-lipid hybrid nanoparticles</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl20" height="42" style="width:188pt;height:31.5pt" width="250">Ultrasonication (UP100H)</td>
			<td class="xl20" style="width:122pt" width="162">Hielscher, Ultrasound Technology</td>
			<td class="xl20" style="width:89pt" width="119">NA</td>
			<td class="xl21">Nanoparticle preparation</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Water Bath (ISOTEMP 3016HS)</td>
			<td class="xl20" style="width:122pt" width="162">Fisher Scientific</td>
			<td class="xl20" style="width:89pt" width="119">NA</td>
			<td class="xl21">Nanoparticle preparation</td>
		</tr>
		<tr height="105" style="height:78.75pt">
			<td class="xl20" height="105" style="width:188pt;height:78.75pt" width="250">Liposomal Doxorubicin&#160; (Caelyx)</td>
			<td class="xl20" style="width:122pt" width="162">Janssen</td>
			<td class="xl20" style="width:89pt" width="119">Purchased from the pharmacy Princess Margaret Hospital</td>
			<td class="xl21">Clinically-approved nanoparticle formulation&#160;</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">HPLC-graded Methanol</td>
			<td class="xl21">Caledon Chemicals</td>
			<td class="xl20" style="width:89pt" width="119">6701-7-40</td>
			<td class="xl21">HPLC mobile phase composition</td>
		</tr>
		<tr height="25" style="height:18.75pt">
			<td class="xl20" height="25" style="width:188pt;height:18.75pt" width="250">HPLC-graded H2O</td>
			<td class="xl21">Caledon Chemicals</td>
			<td class="xl20" style="width:89pt" width="119">8801-7-40</td>
			<td class="xl21">HPLC mobile phase composition</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">HPLC-graded Acetonitrile&#160;</td>
			<td class="xl20" style="width:122pt" width="162">Caledon Chemicals</td>
			<td class="xl20" style="width:89pt" width="119">1401-7-40</td>
			<td class="xl21">HPLC mobile phase composition</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Trifluoroacetic Acid</td>
			<td class="xl20" style="width:122pt" width="162">Sigma-Aldrich</td>
			<td class="xl20" style="width:89pt" width="119">302031</td>
			<td class="xl21">HPLC mobile phase composition</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl20" height="42" style="width:188pt;height:31.5pt" width="250">0.45 &#956;m Nylon Membrane Filter Paper</td>
			<td class="xl20" style="width:122pt" width="162">Whatman</td>
			<td class="xl20" style="width:89pt" width="119">WHA7404004</td>
			<td class="xl21">HPLC mobile phase preparation</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl29" height="42" style="height:31.5pt">1cc Plastic Syringes</td>
			<td class="xl20" style="width:122pt" width="162">Becton, Dickinson and Company</td>
			<td class="xl20" style="width:89pt" width="119">2606-309659</td>
			<td class="xl21">Treatment injection</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl29" height="42" style="height:31.5pt">5cc Plastic Syringes</td>
			<td class="xl20" style="width:122pt" width="162">Becton, Dickinson and Company</td>
			<td class="xl20" style="width:89pt" width="119">2608-309646</td>
			<td class="xl21">Tissue collections</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl20" height="42" style="width:188pt;height:31.5pt" width="250">30G 1/2 Needles</td>
			<td class="xl20" style="width:122pt" width="162">Becton, Dickinson and Company</td>
			<td class="xl20" style="width:89pt" width="119">305106</td>
			<td class="xl21">Treatment injection</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl20" height="42" style="width:188pt;height:31.5pt" width="250">25G 5/8 Needles</td>
			<td class="xl20" style="width:122pt" width="162">Becton, Dickinson and Company</td>
			<td class="xl20" style="width:89pt" width="119">305122</td>
			<td class="xl21">Tissue collections</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl20" height="42" style="width:188pt;height:31.5pt" width="250">Sterile 0.9% Saline</td>
			<td class="xl20" style="width:122pt" width="162">Univeristy of Toronto House Brand</td>
			<td class="xl20" style="width:89pt" width="119">1011</td>
			<td class="xl21">Tissue perfusion</td>
		</tr>
		<tr height="22" style="height:16.5pt">
			<td class="xl20" height="22" style="width:188pt;height:16.5pt" width="250">13 ml Rounded-bottom conical tube&#160;</td>
			<td class="xl20" style="width:122pt" width="162">SARSTEDT</td>
			<td class="xl20" style="width:89pt" width="119">62.515.006</td>
			<td class="xl21">Prolyprolene, tissue homogenization</td>
		</tr>
		<tr height="23" style="height:17.25pt">
			<td class="xl30" height="23" style="height:17.25pt">Alpha Minimum Essential Medium (MEM)&#160;</td>
			<td class="xl27">Gibco</td>
			<td class="xl28" style="width:89pt" width="119">12571063</td>
			<td class="xl21">Cell medium</td>
		</tr>
		<tr height="22" style="height:16.5pt">
			<td class="xl20" height="22" style="width:188pt;height:16.5pt" width="250">1 x Phosphate Buffer Saline</td>
			<td class="xl20" style="width:122pt" width="162">Gibco</td>
			<td class="xl20" style="width:89pt" width="119">10010023</td>
			<td class="xl21">Tissue homogenization</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Triton X-100</td>
			<td class="xl20" style="width:122pt" width="162">Sigma-Aldrich</td>
			<td class="xl20" style="width:89pt" width="119">X100-100 ML</td>
			<td class="xl21">Tissue homogenization</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Formic acid</td>
			<td class="xl20" style="width:122pt" width="162">Caledon Chemicals</td>
			<td class="xl20" style="width:89pt" width="119">1/5/3840</td>
			<td class="xl21">Adjust pH for extraction solvent</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl20" height="42" style="width:188pt;height:31.5pt" width="250">Sodium heparin sprayed plastic tubes</td>
			<td class="xl20" style="width:122pt" width="162">Becton, Dickinson and Company</td>
			<td class="xl20" style="width:89pt" width="119">367878</td>
			<td class="xl21">Blood collection</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Analytical Weigh Balance&#160;</td>
			<td class="xl20" style="width:122pt" width="162">Sartorius&#160;</td>
			<td class="xl21">CPA225D</td>
			<td class="xl21">NA</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">pH meters&#160;</td>
			<td class="xl20" style="width:122pt" width="162">Fisher Scientific</td>
			<td class="xl26">13-637-671</td>
			<td class="xl21">accumet BASIC</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Vortex Mixter</td>
			<td class="xl20" style="width:122pt" width="162">Fisher Scientific</td>
			<td class="xl20" style="width:89pt" width="119">02-215-365</td>
			<td class="xl21">Vortexing samples at desired speed</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">1.5 ml&#160; Microcentrifuge Tube</td>
			<td class="xl20" style="width:122pt" width="162">Fisherbrand</td>
			<td class="xl20" style="width:89pt" width="119">2043-05408129</td>
			<td class="xl21">Prolyprolene</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Model 1000 homogenizer</td>
			<td class="xl22">Fisher Scientific</td>
			<td class="xl20" style="width:89pt" width="119">08-451-672</td>
			<td class="xl21">Tissue homogenization</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Centrifuge 5702R</td>
			<td class="xl20" style="width:122pt" width="162">Eppendorf</td>
			<td class="xl20" style="width:89pt" width="119">5702R</td>
			<td class="xl21">Extraction preparation</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Heated Evaporator System</td>
			<td class="xl20" style="width:122pt" width="162">Glas-Col</td>
			<td class="xl20" style="width:89pt" width="119">NA</td>
			<td class="xl21">Sample reconstitution</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">HPLC Screw Thread Vials</td>
			<td class="xl20" style="width:122pt" width="162">DIKMA</td>
			<td class="xl20" style="width:89pt" width="119">5320</td>
			<td class="xl21">HPLC sample injection</td>
		</tr>
		<tr height="42" style="height:31.5pt">
			<td class="xl20" height="42" style="width:188pt;height:31.5pt" width="250">HPLC Screw Caps with PTFE White Silicone Septa</td>
			<td class="xl20" style="width:122pt" width="162">DIKMA</td>
			<td class="xl20" style="width:89pt" width="119">5325</td>
			<td class="xl21">HPLC sample injection</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">HPLC Polypropylene Insert&#160;&#160;</td>
			<td class="xl20" style="width:122pt" width="162">Agilent Technologies</td>
			<td class="xl20" style="width:89pt" width="119">5182-0549</td>
			<td class="xl21">Maximum volume 250 &#956;l, HPLC sample injection</td>
		</tr>
		<tr height="25" style="height:18.75pt">
			<td class="xl20" height="25" style="width:188pt;height:18.75pt" width="250">Xbridge C18 Column</td>
			<td class="xl23">Waters Corporation</td>
			<td class="xl20" style="width:89pt" width="119">186003117</td>
			<td class="xl21">Drug analysis</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Gradient pump&#160;</td>
			<td class="xl23">Waters Corporation</td>
			<td class="xl20" style="width:89pt" width="119">W600</td>
			<td class="xl21">Drug analysis</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Auto-sampler</td>
			<td class="xl23">Waters Corporation</td>
			<td class="xl20" style="width:89pt" width="119">W2707</td>
			<td class="xl21">Drug analysis</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Photodiode array detector&#160;</td>
			<td class="xl23">Waters Corporation</td>
			<td class="xl20" style="width:89pt" width="119">W2998</td>
			<td class="xl21">Drug analysis</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Multi &#955; fluoresence detector&#160;</td>
			<td class="xl23">Waters Corporation</td>
			<td class="xl20" style="width:89pt" width="119">W2475</td>
			<td class="xl21">Drug analysis</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">EMPOWER 2</td>
			<td class="xl23">Waters Corporation</td>
			<td class="xl20" style="width:89pt" width="119">NA</td>
			<td class="xl21">Data analysis software</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Scientist</td>
			<td class="xl20" style="width:122pt" width="162">Micromath</td>
			<td class="xl20" style="width:89pt" width="119">NA</td>
			<td class="xl21">Pharmacokinetic analysis</td>
		</tr>
		<tr height="21" style="height:15.75pt">
			<td class="xl20" height="21" style="width:188pt;height:15.75pt" width="250">Female Balb/c Mice</td>
			<td class="xl20" style="width:122pt" width="162">Jackson Laboratory</td>
			<td class="xl20" style="width:89pt" width="119">001026</td>
			<td class="xl21">In vivo</td>
		</tr>
		<tr height="63" style="height:47.25pt">
			<td class="xl20" height="63" style="width:188pt;height:47.25pt" width="250">EMT6/WT Breast Cancer Cells</td>
			<td class="xl20" style="width:122pt" width="162">Provided by Dr. Ian Tannock; Ontario Cancer Institute</td>
			<td class="xl20" style="width:89pt" width="119">NA</td>
			<td class="xl21">In vivo</td>
		</tr>
	</tbody>
</table>

sample extraction and simultaneous chromatographic quantitation of doxorubicin and mitomycin c following drug combination delivery in nanoparticles to tumor-bearing mice

Combination chemotherapy is frequently used in the clinic for cancer treatment; however, associated adverse effects to normal tissue may limit its therapeutic benefit. Nanoparticle-based drug combination has been shown to mitigate the problems encountered by free drug combination therapy. Our previous studies have shown that the combination of two anticancer drugs, doxorubicin (DOX) and mitomycin C (MMC), produced a synergistic effect against both murine and human breast cancer cells in vitro. DOX and MMC co-loaded polymer-lipid hybrid nanoparticles (DMPLN) bypassed various efflux transporter pumps that confer multidrug resistance and demonstrated enhanced efficacy in breast tumor models. Compared to conventional solution forms, such superior efficacy of DMPLN was attributed to the synchronized pharmacokinetics of DOX and MMC and increased intracellular drug bioavailability within tumor cells enabled by the nanocarrier PLN. 
To evaluate the pharmacokinetics and bio-distribution of co-administered DOX and MMC in both free solution and nanoparticle forms, a simple and efficient multi-drug analysis method using reverse-phase high performance liquid chromatography (HPLC) was developed. In contrast to previously reported methods that analyzed DOX or MMC individually in the plasma, this new HPLC method is able to simultaneously quantitate DOX, MMC and a major cardio-toxic DOX metabolite, doxorubicinol (DOXol), in various biological matrices (e.g., whole blood, breast tumor, and heart). A dual fluorescent and ultraviolet absorbent probe 4-methylumbelliferone (4-MU) was used as an internal standard (I.S.) for one-step detection of multiple drug analysis with different detection wavelengths. This method was successfully applied to determine the concentrations of DOX and MMC delivered by both nanoparticle and solution approaches in whole blood and various tissues in an orthotopic breast tumor murine model. The analytical method presented is a useful tool for pre-clinical analysis of nanoparticle-based delivery of drug combinations.

Two anticancer drugs, DOX and MMC, as well as the DOX metabolite, DOXol, were simultaneously detected without any biological interference under the same applied gradient HPLC condition using 4-MU as the I.S. for both the fluorescence and UV detectors. DOX, MMC, DOXol and 4-MU were well-separated from each other with retention times of 5.7 min for MMC, 10.4 min for DOXol, 10.9 min for 4-MU, and 11.1 min for DOX (Figure 2). Each drug in whole blood and various ...

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Sample Extraction and Simultaneous Chromatographic Quantitation of Doxorubicin and Mitomycin C Following Drug Combination Delivery in Nanoparticles to Tumor-bearing Mice

This protocol describes an efficient and convenient analytical process of sample extraction and simultaneous determination of multiple drugs, doxorubicin (DOX), mitomycin C (MMC) and a cardio-toxic DOX metabolite, doxorubicinol (DOXol), in the biological samples from a preclinical breast tumor model treated with nanoparticle formulations of synergistic drug combination.

Combination chemotherapy is frequently used in the clinic for cancer treatment; however, associated adverse effects to normal tissue may limit its ...

The overall goal of this analytical protocol is to simultaneously extract and quantitate the two anti-cancer drugs Doxorubicin and Mitomycin C, co-delivered by polymer-lipid hybrid nanoparticles, and the Doxorubicin's metabolite, Doxorubicinol, in biological matrices using a simple and robust reverse phase high performance liquid chromatography method. This method can help answer key questions in the field in nanomedicine, such as how to design an effective nanocarry system based on the nanopharmacokinetics of drug combinations. The main advantage of this technique is that it allows for the simultaneous quantitation of three drug compounds in the same biological matrix, without the need to change the mobile phase of HPLC.So, this method can provide insight into the biological behaviors of Doxorubicin, Mitomycin C, and Doxorubicinol in primary breast tumors. It can also be applied to other cancer types treated with similar drugs. Visual demonstration of this method is critical, as efficient sample preparation steps are difficult to learn.To begin this procedure, collect and freeze the whole blood, major organs, and breast tumor as outlined in the text protocol. Quickly weigh the frozen tissues and record the weight on the lab note book. Then, transfer them into a 13 milliliter round bottom conical tube.Next, add between one and five milliliters of ice cold Cell Lysis buffer. Using an electric hand homogenizer, homogenize the tissue with an up and down stroke motion on ice at 18, 000 rpm. After this, wash the homogenizer's 10 millimeter saw tooth generator probe with distilled deionized water.Wash the probe with 70%ethanol, and then again with distilled deionized water. Transfer 50 microliters of either tissue homogenate or whole blood to a 1.5 milliliter polypropylene microcentrifuge tube. Then, spike with five microliters of a 2, 000 nanogram per milliliter internal standard 4-MethylUmbelliferone.Add an ice cold extraction solvent containing 150 microliters of acetonitrile and 100 microliters of five millimolar ammonium acetate. Vigorously vortex the mixture for two minutes. Centrifuge at 3, 000 g and four degrees celsius for 10 minutes.After this, transfer 200 microliters of the supernatant to a fresh, pre-chilled microcentrifuge tube. Use a slow stream of nitrogen gas to evaporate the supernatant at 60 degrees celsius with protection from light. Next, reconstitute the dried residue with 100 microliters of ice cold methanol.Vigorously vortex for 30 seconds. Centrifuge at 3, 000 g and four degrees celsius for five minutes. Then, transfer the supernatant into an HPLC vial insert.Place the sample vials into an autosampler tray for injection. To begin, prepare the HPLC mobile phase as outlined in the text protocol. Set the initial conditions of the mobile phase composition to 16.5%H2O, and 83.5%acetonitrile.Set the Isocratic Flow Rate to 1.0 milliliters per minute. Then, separate the drugs using gradient mobile phase condition as outlined in the text protocol. Next, set the UV detector on two channels:one at 310 nanometers for internal standard 4-MethylUmbelliferone and the other at 360 nanometers for Mitomycin C.After this, set the first channel of the florescence detector to an excitation wavelength of 365 nanometers, and an emission wavelength of 445 nanometers for 4-MethylUmbelliferone.Set the second channel to an excitation wavelength of 480 nanometers, and an emission wavelength of 560 nanometers for Doxorubicin and Doxorubicinol. To begin, use the autosampler to inject 15 microliters of the sample. The programmed gradient mobile phase composition changes automatically by increasing the composition of acetonitrile over zero to 18 minutes.After 18 minutes, the mobile phase condition is reestablished to the initial condition and re-equilibrated for the next injection. After each sample is run, note the peaks of the drug compounds and their retention times. Then, use the HPLC software to integrate the peak area under the curve for the drug compounds.Calculate the drug recovery percentage and the area under the curve ratio between each drug compound and the internal standard, as outlined in the text protocol. In this procedure, two anticancer drugs, Doxorubicin and Mitomycin C, along with the Doxorubicin metabolite, Doxorubicinol, are detected without biological interference. HPLC analysis shows that each drug is well separated from the others.The HPLC method developed displays less than 15%variation in intra-and inter-day precision and accuracy for each of the drugs studied, in both whole blood and various biological matrices, indicating excellent reproducibility. The pharmacokinetic and bio distribution of long circulating or pegylated nanoparticle based co-delivery of Doxorubicin and Mitomycin C are then determined. In the blood, drug concentrations delivered by polymer-lipid hybrid nanoparticles over time are seen to be at least six fold higher than in the equivalent free drug solutions.In an orthotopic breast tumor, polymer-lipid hybrid nanoparticles can co-deliver Doxorubicin and Mitomycin C at their synergistic drug ratio. Compared to free drug solution, nanoparticles are seen to have increased tumor accumulation. This is due to the prolonged systematic circulation, which allows the nanoparticles to exploit the enhanced permeability and retention effects of the tumor.Further quantitatively determined formation of Doxorubicinol in the breast tumor over 24 hours, along with Enhanced Tumor Apoptosis, indicates that drug bioavailability is critical in designing an effective nanoparticle formulation. Using this HPLC method, it was successfully demonstrated that polymer-lipid hybrid nanoparticles can precisely deliver synergistic drug combination into cancer cells in vivo, leading to improved chemotherapy. This technique can be done in about two hours if it is performed properly.To minimize potential drug depredation, it is important to remember to avoid direct sunlight and to keep sample on ice while attempting this procedure. After its development, this technique paved the way for the researcher in the field of nanomedicine to explore nanopharmacokinetics of the drug combination, and to better design the effective nanoparticle formulation for cancer therapy. After watching this video, you should understand how to simultaneous extract and to detect Doxorubicin, Mitomycin C, and Doxorubicin's metabolite, Doxorubicinol, over a wide ranges of the biological samples containing nanoparticle loaded the drug combination.Don't forget that working with anticancer drugs and acid can be extremely hazardous, and safety precautions such as wearing gloves, goggles, and lab coats should always be applied while performing this protocol.

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10.8K Görüntüleme.  University of Toronto. The overall goal of this analytical protocol is to simultaneously extract and quantitate the two anti-cancer drugs Doxorubicin and Mitomycin C, co-delivered by polymer-lipid hybrid nanoparticles, and the Doxorubicin's metabolite, Doxorubicinol, in biological matrices using a simple and robust reverse phase high performance liquid chromatography method. This method can help answer key questions in the field in nanomedicine, such as how to design an effective nanocarry system based on the nanop...

Video: Sample Extraction and Simultaneous Chromatographic Quantitation of Doxorubicin and Mitomycin C Following Drug Combination Delivery in Nanoparticles to Tumor-bearing Mice